Unitod Sortss
Environmamal Protnction
Agancy
Office of Waur Regulations
and Standards (WH-552)
Industrial Technology Drvtsior
Washington, DC 20460
EPA 440TI-89-0192
May 1989
Office of Water
Development "FINAL
Document for
Effluent Limitations
Guidelines and
Standards for the
Nonferrous Metals
Manufacturing
Point Source
Category
Volume II
Bauxite Refining
Primary Aluminum Smelting
Secondary Aluminum Smelting
-------
DEVELOPMENT DOCUMENT
for
EFFLUENT LIMITATIONS GUIDELINES AND STANDARDS
for the
NONFERROUS METALS MANUFACTURING POINT SOURCE CATEGORY
VOLUME II
Bauxite Refining
Primary Aluminum Smelting
Secondary Aluminum Smelting
William K. Reilly
Administrator
Rebecca Hanmer, Acting
Assistant Administrator for Water
Martha Prothro, Director
Office of Water Regulations and Standards
KWJ
Thomas P. O'Farrell, Director
Industrial Technology Division
Ernst P. Hall, P.E., Chief
Metals Industry Branch
and
Technical Project Officer
May 1989
U.S. Environmental Protection Agency
Office of Water
Office of Water Regulations and Standards
Industrial Technology Division
Washington, D. C. 20460
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TABLE OF CONTENTS
Supplement Page
Bauxite Refining 505
Primary Aluminum Smelting 591
Secondary Aluminum Smelting 859
For detailed contents see detailed contents list in
individual supplement.
i i i
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NONFERROUS METALS MANUFACTURING POINT SOURCE CATEGORY
DEVELOPMENT DOCUMENT SUPPLEMENT
for the
Bauxite Refining Subcategory
William K. Reilly
Administrator
Rebecca Hanmer
Acting Assistant Administrator for Water
Martha Prothro, Director
Office of Water Regulations and Standards
*
*
KS&J
Thomas P. O'Farrell, Director
Industrial Technology Division
Ernst P. Hall, P.E., Chief
Metals Industry Branch
and
Technical Project Officer
May 1989
U.S. Environmental Protection Agency
Office of Water
Office of Water Regulations and Standards
Industrial Technology Division
Washington, D. C. 20460
505
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BAUXITE REFINING SUBCATEGORY
TABLE OF CONTENTS
Section Page
I SUMMARY AND CONCLUSIONS 513
II RECOMMENDATIONS 517
III INDUSTRY PROFILE 519
Description of Bauxite Refining Processes 519
Raw Materials 520
Bauxite Grinding and Digestion 520
Red Mud Removal and Liquor Purification 521
Precipitation and Classification 522
Calcination 523
Process Wastewater Sources 524
Other Wastewater Sources 524
Age, Production, and Process 524
Profile
IV SUBCATEGORIZATION 531
Factors Considered in 531
Subcategorization
Factors Considered in Subdividing 531
The Bauxite Refining Subcategory
Other Factors 532
Type of Plant 532
Raw Materials 532
Plant Location 533
V WATER USE AND WASTEWATER 535
CHARACTERISTICS
Wastewater Characteristics Data 536
Data Collection Portfolios 536
Field Sampling Data 536
Wastewater Characteristics and 538
Flows by Building Block
Digestor Condensate 538
Barometric Condenser Effluent 538
Carbonation Plant Effluent 538
Mud Impoundment Effluent 539
507
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555
555
555
556
556
558
559
559
559
569
569
569
570
570
571
571
571
571
572
572
572
572
575
BAUXITE REFINING SUBCATEGORY
TABLE OF CONTENTS (Continued)
Page
SELECTION OF POLLUTANT PARAMETERS
Conventional and Nonconventional Pollutant
Parameters
Conventional and Nonconventional Pollutant
Parameters Selected
Toxic Priority Pollutants
Toxic Pollutants Never Detected
Toxic Pollutants Never Found Above Their
Analytical Quantification Level
Toxic Pollutants Present Below Concentrations
Achievable by Treatment
Toxic Pollutants Detected in a Small Number of
Sources
Toxic Pollutants Selected for Further
Consideration for Limitation
CONTROL AND TREATMENT TECHNOLOGIES
Current Control and Treatment Practices
Mud Impoundment Effluent
Control and Treatment Options
Option E
COSTS OF WASTEWATER TREATMENT AND CONTROL
Treatment Options Costs for Existing Sources
Option E
Cost Methodology
Nonwater Quality Aspects
Energy Requirements
Solid Waste
Air Pollution
BEST PRACTICABLE TECHNOLOGY CURRENTLY AVAILABLE
508
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577
577
577
579
579
579
579
580
581
581
581
585
585
585
586
586
586
586
587
589
BAUXITE REFINING SUBCATEGORY
TABLE OF CONTENTS (Continued)
Page
BEST AVAILABLE TECHNOLOGY
ECONOMICALLY ACHIEVABLE
Technical Approach to BAT
Option E
Industry Cost and Pollutant Removal Estimates
Pollutant Removal Estimates
Compliance Costs
BAT Option Selection
Regulated Pollutant Parameters
Effluent Limitations
Recommended Guidance for BAT
Effluent Limitations for the Bauxite Refining
Subcategory
NEW SOURCE PERFORMANCE STANDARDS
Technical Approach to NSPS
Option E
NSPS Option Selection
Regulated Pollutant Parameters
New Source Performance Standards
Recommended Guidance for NSPS for
the Bauxite Refining Subcategory
PRETREATMENT STANDARDS
BEST CONVENTIONAL POLLUTANT CONTROL TECHNOLOGY
509
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BAUXITE REFINING SUBCATEGORY
Tables
III-l
III-2
III-3
V-l
V-2
V-3
V-4
V-5
VI-1
LIST OF TABLES
Title
Page
Initial Operating Year (Range) 527
Summary of Plant9 in the
Bauxite Refining Subcategory
by Discharge Type
Production Ranges for the Bauxite 528
Refining Subcategory
Summary of Bauxite Refining 526
Subcategory Processes and
Associated Waste Streams
Water Use and Discharge Rates for 540
Mud Impoundment Effluent
(liters/yr)
Bauxite Refining Subcategory 541
Digester Condensate Sampling
Data
Bauxite Refining Subcategory 544
Barometric Condenser (Hot
Well) Discharge Raw
Wastewater Sampling Data
Bauxite Refining Subcategory 547
Carbonation Plant Effluent
Raw Wastewater Sampling
Data
Bauxite Refining Subcategory 549
Mud Lake Discharge Raw
Wastewater Sampling Data
Frequency of Occurrence of 561
Priority Pollutants Bauxite
Refining Raw Wastewater
510
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BAUXITE REFINING SUBCATEGORY
LIST OF TABLES (Continued)
Tables Title Page
VI-2 Toxic Pollutants Never Detected 568
VI-3 Toxic Pollutants Never Found 567
Above Their Quantification Level
VIII-1 Cost of Compliance for the 573
Bauxite Refining Subcategory
Direct Dischargers
X-l Pollutant Removal Estimates 582
Bauxite Refining Subcategory
X-2 Cost of Compliance for the 583
Bauxite Refining Subcategory
511
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BAUXITE REFINING SUBCATEGORY
LIST OF FIGURES
Figures Title Page
III-l Bauxite Refining Process 527
III-2 Geographic Locations of the 529
Bauxite Refining Subcategory
Plants
V-l Sampling Sites at Bauxite 552
Refining Plant A
V-2 Sampling Sites at Bauxite 553
Refining Plant B
X-l Option E Treatment Scheme for 584
the Bauxite Refining
Subcategory
512
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BAUXITE REFINING SUBCATEGORY SECT - I
SECTION I
SUMMARY AND CONCLUSIONS
On April 8, 1974, EPA promulgated effluent limitations based on
best practicable technology currently available (BPT) and
best available technology economically achievable (BAT),
standards of performance for new sources (NSPS) and pretreatment
standards for new sources (PSNS). In each case, the
limitations and standards required no discharge of process
wastewater pollutants with an allowance for discharge of
monthly net precipitation (i.e., the difference in water volume
between precipitation and evaporation in a one month
period) that accumulates in the impoundments used by bauxite
refineries to store the undigested solids produced in the
refining process. This document and the administrative record
provides the technical basis for review of the promulgated
effluent limitations and standards.
The bauxite refining subcategory consists of 8 plants. Of the
8 plants, three discharge directly to rivers, lakes, or streams
and five achieve zero discharge of process wastewater.
EPA first studied the bauxite refining subcategory to determine
whether differences in raw materials, final products,
manufacturing processes, equipment, age and size of plants, or
water usage, required the development of separate effluent
limitations and standards for different segments of the
subcategory. This involved a detailed analysis of wastewater
discharge and treated effluent characteristics, including (1) the
sources and volume of water used, the processes used, and the
sources of pollutants and wastewaters in the plant; and (2) the
constituents of wastewaters, including priority pollutants. As
a result, four subdivisions have been identified for
this subcategory'that warrant separate effluent limitations.
These include:
o Digester Condensate
o Barometric Condenser Effluent
o Carbonation Plant Effluent
o Mud Impoundment Effluent
EPA al90 identified several distinct control and treatment
technologies (both in-plant and end-of-pipe) applicable to the
bauxite refining subcategory. The Agency analyzed both
historical and newly generated data on the performance of these
technologies, including the non-water quality environmental
impacts and air quality, solid waste generation,
and energy requirements. EPA also studied flow reduction
513
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BAUXITE REFINING SUBCATEGORY SECT - I
reported in the data collection portfolios (dcp) and plant
visits.
Engineering costs were prepared for each discharging plant (and
one zero discharger) for the control and treatment option
considered for the subcategory. These costs were then used by
the Agency to estimate the impact of implementing the option in
the subcategory. For this control and treatment option, the
number of potential closures, number of employees affected, and
impact on price were estimated. These results are reported in a
separate document entitled "The Economic Impact Analysis of
Proposed Effluent Limitations Guidelines and Standards for the
Nonferrous Smelting and Refining Industry."
After examining the various treatment technologies being operated
in the subcategory, the Agency has identified BPT to be
equivalent to the existing promulgated BPT effluent limitations
published on April 8, 1974 (40 CFR Part 421 Subpart A). This
requires no discharge of process wastewater pollutants to
navigable waters, while permitting the discharge of net
precipitation from red mud lake impoundments. Minor amendments
to the regulatory language are promulgated to clarify
references to fundamentally different factors (FDF)
considerations under 40 CFR Part 125 and
references to pretreatment standards under 40 CFR Part 128. As
a result, the bauxite refining subcategory will not incur
any incremental capital or annual costs to comply with the BPT
limitations.
For BAT, the Agency considered revising the promulgated BAT to
include treatment of the allowable discharge of net
precipitation from mud impoundments by pH adjustment and
activated carbon adsorption technology for removal of organic
pollutants. This potential . revision was based on new
data collected by the Agency since the previous promulgation
that indicated the presence of phenolic compounds at
treatable concentrations in the mud impoundment effluent.
Since proposal the Agency has received newly collected
data for the red mud lakes showing levels below the limit of
detection for all phenolic compounds except phenol. As a result,
the Agency has decided not to establish additional national
effluent limitations guidelines and standards for this
subcategory but rather to recommend guidance to permitting
authorities to deal with any site-specific high levels of
phenolics.
The technical basis of NSPS is equivalent to the existing
promulgated BAT. In selecting NSPS, EPA recognizes that new
plants have the opportunity to implement the best and most
efficient manufacturing processes and treatment technology.
However, no such processes or treatment technology were
considered to meet the NSPS criteria. Therefore, the technology
basis of BAT has been determined as the best demonstrated
technology, the technology basis of NSPS. The Agency was also
considering the application of pH adjustment and activated
514
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BAUXITE REFINING SUBCATEGORY SECT - I
carbon adsorption technology to the mud impoundment effluent for
new sources. The Agency is not revising the promulgated
NSPSr but is recommending guidance to permitting authorities to
deal with any site-specific high levels of phenolics.
The limitations and standards for BPT, BAT, NSPS, and PSNS are
presented in Section II.
515
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BAUXITE REFINING SUBCATEGORY SECT-II
SECTION II
RECOMMENDATIONS
EPA is not changing the existing promulgated BPT for the
bauxite refining subcategory. The regulation establishes no
discharge of process wastewater pollutants with an allowance for
discharge of net precipitation from the mud impoundment. The
technology basis for BPT is impoundment and recycle for all
process wastewater.
EPA is not substantially modifying the existing promulgated BAT
limitations. However, the Agency is providing guidance in Section
X for the control of phenolics.
Similar to BAT, EPA is not substantially modifying the
existing promulgated NSPS, but is recommending guidance in
section XI for the control of phenolics.
EPA is not promulgating PSES limitations for the bauxite
refining subcategory because there are no existing indirect
dischargers.
EPA is not modifying the existing promulgated PSNS since it is
unlikely that any new bauxite sources could be constructed as
indirect dischargers.
EPA is not promulgating best conventional pollutant control
technology (BCT) limitations at this time.
517
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BAUXITE REFINING SUBCATEGORY SECT-III
SECTION III
INDUSTRY PROFILE
This section of the bauxite refining supplement describes the raw
materials and processes used in refining bauxite to produce
alumina and presents a profile of the alumina plants identified
in this study. For a discussion of the purpose, authority, and
methodology for this study and a general description of the non-
ferrous metals manufacturing category, refer to Section III of
the General Development Document.
EPA promulgated effluent limitations for BPT and BAT, new source
performance standards, and pretreatment standards for new sources
for the bauxite refining subcategory on April 8, 1974 as Subpart
A of 40 CFR Part 421. The pollutants considered in the
development of those regulations included alkalinity, pH, total
dissolved solids, total suspended solids, and sulfate.
The Clean Water Act of 1977 mandates the achievement of effluent
limitations requiring the application of BAT for
toxic pollutants. In keeping with this emphasis on toxic
pollutants, EPA is re-examining the discharge of toxic
pollutants from process wastewater impoundments in the
bauxite refining subcategory.
Most of the alumina produced by bauxite refiners is sold to the
primary aluminum industry. Aluminum metal is widely used for
building and construction materials, transportation equipment,
and containers and packaging products. The remainder of the
alumina is sold to the chemical, abrasive, ceramic, and
refractory industries for the manufacture of products such as
chemical alums, activated alumina, polishes, electrical
insulators, and heat exchange media.
DESCRIPTION OF BAUXITE REFINING PROCESSES
Bauxite is the only ore of aluminum used commercially in the
United States. Aluminum production is unique among metal
manufacturing techniques in that nearly all purification is
accomplished in the bauxite refining process. No significant
removal of impurities occurs during the subsequent reduction to
metal.
In the United States, bauxite is refined using the Bayer process.
The classic Bayer process may be broadly divided into four major
operations:
1. Bauxite grinding and digestion,
2. Red mud removal and liquor purification,
3. Precipitation and classification, and
519
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BAUXITE REFINING SUBCATEGORY SECT-III
4. Calcination.
A variation of the process, known as the combination process,
allows additional alumina recovery from solid residues when high-
silica bauxites are used as the raw material.
Bauxite refining is characteristically conducted in very large
scale installations. The process is conducted in an essentially
closed circuit with extensive reuse and recycle of process water.
Economic considerations make the maximum recovery of heat and
reagents a necessity. Production processes for the bauxite
refining subcategory are presented schematically in Figure III-l
(page 527) and described in detail below.
RAW MATERIALS
Bauxite consists of hydrated aluminum oxide and various
impurities, including iron oxide, titanium dioxide, silicon
dioxide, and compounds of phosphorus and vanadium. A basic
distinction is made between monohydrate bauxite, which contains
alumina in the form of boehmite or diaspore (AI2O3 H2O),
and trihydrate bauxite, in the form of gibbsite (Al203'3H20
or Al(0H)3), because they require different digestion
conditions. Further distinctions of ore type include high or
low silica content, high or low iron content, and fast- or
slow-settling red mud after digestion.
BAUXITE GRINDING AND DIGESTION
Bauxite ore is crushed and wet-ground with a caustic-rich
solution in preparation for the digestion process. The bauxite
must be ground finely enough to ensure effective digestion but
not so finely that the red mud residue presents problems during
settling and filtration. One plant reports the use of scrubbers
for dust control in the bauxite handling operations. Because the
water from these scrubbers is returned to the process to recover
the bauxite value, it is considered to be a process water stream
rather than a wastewater stream.
The ground bauxite slurry is fed to digesters where the hydrated
alumina in the bauxite is converted to a soluble salt, sodium
aluminate. The reaction is accomplished using either sodium
hydroxide or a combination of lime and sodium carbonate.
Wastewater from wet air pollution control on lime kilns at two
plants is sent to the digesters. Because the scrubber effluent
is returned to the process and not discharged, it is considered
to be a process water stream rather than a wastewater stream.
Digestion conditions (temperature, pressure, and caustic
concentration) depend on the type of bauxite processed.
Monohydrate bauxites require temperatures between 200 and
250°C at up to 35 atm pressure. Trihydrate bauxites can be
digested under the more moderate conditions of 120 to 170°C and
3 to 5 atm pressure.
520
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BAUXITE REFINING SUBCATEGORY SECT-III
The product of the digestion process is a slurry containing
sodium aluminate in aqueous solution and undissolved solids.
This slurry enters a system of expansion vessels or "flash tanks"
for cooling, pressure reduction, and heat recovery. The stream
recovered from the expansion process is returned to the digesters
to provide some of the heat needed to maintain proper digestion
temperatures. Condensate from the vapor is frequently used for
boiler water. At one plant condensate is used for hydrate
washing. Excess condensate or condensate which is unsuitable for
use in boilers may be disposed of.
RED MUD REMOVAL AND LIQUOR PURIFICATION
The digested bauxite suspension contains solid, insoluble bauxite
particles of various sizes and compositions in a sodium aluminate
solution. Particles above a certain size, e.g., 100 microns, are
called "sand" and may include undigested bauxite, quartz
particles, or common sand. Sand is usually removed from the
suspension before red mud thickening.
The insoluble residue remaining in suspension after desanding is
commonly known as red mud. Red mud contains iron oxides,
titanium dioxide, aluminum present with silica, and other
secondary impurities. A flocculating agent is added to the
process suspension to enhance settling of the fine red mud
par tides.
The overflow from the mud settling and thickening steps is
further clarified by filtration. This step removes red mud
particles from the supersaturated aluminate liquor.
The red mud settled from the process liquor is thickened, washed,
and sometimes filtered to recover caustic and alumina values.
The mud is then moved as a waterborne slurry to a waste area
known as a red mud lake or impoundment for disposal.
When high-silica bauxites such as those from Arkansas are used as
the raw material for alumina production, the "combination
process" can be applied to recover alumina and sodium values
which would otherwise be lost in the red mud. As much as one-
third of the total alumina value produced by a plant using
Arkansas bauxite may be trapped in insoluble sodium
aluminosilicates which are removed from the process with the red
mud.
In the combination process, the red mud is treated first by
filtration to reduce the evaporative load and then by sintering
and leaching to recover alumina. After filtering and washing,
the remaining solid residue or "brown mud" is sent to a mud lake
for disposal. The very pure filtrate, known as white liquor, is
either combined with the process stream or precipitated and
calcined separately to produce chemical-grade alumina.
Red muds from various bauxites have different characteristics
521
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BAUXITE REFINING SUBCATEGORY SECT-III
which produce differing disposal considerations. For example,
the yield of red mud residue from Surinam bauxite is low
(approximately 1/3 kkg per kkg of alumina product), and the mud
is amenable to filtration and effective washing on a filter.
Thus, the final residue is relatively easy to handle and disposal
area requirements are moderate. On the other hand, red muds from
Arkansas and Jamaican bauxites are produced in much greater
yield, (approximately 2 kkg and 1 kkg per kkg of alumina,
respectively), because of their larger content of contaminants.
The physical characteristics of Jamaican bauxite red mud are such
that filtration is difficult and countercurrent decantation may
be required. It also settles poorly, reaching a solids
concentration of only about 30 percent after normal settling as
compared to more than 50 percent solids for the muds from other
ores. As a result, area requirements for these red mud lakes are
large.
One company which refines Jamaican bauxite has developed a sand
bed filtration technique. In this technique, red mud is pumped
to a drying bed where the solids concentration of the mud is
increased from 15 or 20 percent to more than 50 percent. The
surface of the mud drying bed is kept dry by drawing water off
the top and, at one of the two plants using sand bed filtration,
pumping it to a "clear lake." Underflow is also drawn out through
the sandy bottom of the bed and sent to the clear lake. Clear
lake water is then recycled to the bauxite refining operations
for use as process water, forming a nearly-closed water system.
The second plant that practices sand bed filtration of red mud
wastes does not have a clear lake, practices no recycle of mud
lake water to the process, and discharges neutralized effluent
directly to surface waters.
Of the alumina plants which do not practice sand bed filtration
of red mud, all report the use of red mud lakes. In addition, a
refinery may have a process water lake for recycle of higher
quality water than is found in the mud lake and a storm water
lake to collect large volumes of rainwater runoff from the plant
site. Minor remaining storage capacity in abandoned red mud
lakes may be utilized to dispose of small quantities of aqueous
wastes which are intolerable in the recycle circuit. Examples of
such wastes are spent acids from equipment cleaning and the
effluent from salting-out evaporators.
PRECIPITATION AND CLASSIFICATION
The purified sodium aluminate solution obtained by removing solid
impurities from the digested liquor passes through heat
exchangers and is cooled before being discharged into large
precipitation vessels. Vapor produced in the flash cooling area
is condensed and reused in other parts of the plant.
During precipitation, aluminum hydroxide crystallizes from the
super-saturated sodium aluminate in the presence of seed
crystals. The precipitation conditions are carefully controlled
so that the solids formed will be amenable to easy separation and
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BAUXITE REFINING SUBCATEGORY SECT-III
washing. The precipitated hydrate crystals are classified by
size; small crystals are washed and fed to calcining furnaces.
Aluminum trihydrate scale can also be recovered from the
precipitators and processed to make an activated alumina by-
product .
The spent liquor separated from the hydrate crystals during
classification is returned to the grinding and digestion
processes to recover the caustic value of the stream. The spent
caustic is first heated in heat exchangers by the steam recovered
from the flash cooling of the process liquor before
precipitation. The liquor then passes through evaporators which
remove excess water. The caustic is thus reconcentrated before
being mixed with the bauxite ore in the digesters.
The vapor generated in the spent caustic evaporators is condensed
in barometric condensers using once-through cooling water.
Although occasional upsets may cause entrainment of caustic, the
barometric condensate, also referred to as hotwell discharge,
from properly operated evaporators is generally a high quality
water which is either impounded with the red mud or discharged
directly to surface waters.
Some provision must be made to bleed off a part of the recycled
caustic to prevent the accumulation of soluble salts in the
system. In some plants, one of the evaporators is a "salting-
out" evaporator which concentrates a portion of the recycled
caustic stream. The concentrated stream is then disposed of in
an old mud lake or a landfill.
An alternate method of removing salts is to mix some of the spent
liquor with the slurry from the digesters. The soluble
contaminants are removed by the red mud which is then filtered
out and discarded. This technique of salt removal has been
demonstrated in only one plant and may not be possible with red
mud from all bauxite ore types.
One plant removes soluble salts from the process by carbonating a
small amount of pregnant liquor from the precipitation process
and some of the hydrate seed. An alumina precipitate is settled
from the carbonated mixture and calcined. The recovered sodium
aluminate is then returned to the process at the mixing and
digestion operation. The solution from which the alumina was
precipitated contains neutralized soluble impurities and is
directly discharged without further treatment.
CALCINATION
The moist filter cake of aluminum oxide from the precipitation
and classification operations is conveyed to calciners where it
is converted to anhydrous alumina, the form most suitable for
later use in electrolytic reduction to aluminum metal. Dust
control for the calciners is provided by electrostatic
precipitators or baghouse filters.
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BAUXITE REFINING SUBCATEGORY SECT-III
One plant dries part of the hydrate filter cake rather than
exposing it to the more severe conditions of calcination. The
product of this operation is sold as a dried hydrate. Condensate
from the dryers is collected and reused in the precipitation
process.
PROCESS WASTEWATER SOURCES
A variety of processes are involved in bauxite refining. The
significant wastewater sources that are associated with this
subcategory can be subdivided as follows:
1. Digester condensate,
2. Barometric condenser effluent,
3. Carbonation plant effluent, and
4. Mud impoundment effluent.
OTHER WASTEWATER SOURCES
There are other waste streams associated with the bauxite
refining subcategory. These waste streams include, but are not
limited to:
1. Stormwater other than that which falls within the
process water impoundment area, and
2. Maintenance and cleanup water.
These waste streams are not considered as a part of this
rulemaking. EPA believes that the flows and pollutant loadings
associated with these waste streams are insignificant relative to
the waste streams selected, or are best handled by the
appropriate permit authority on a case-by-case basis under
authority of Section 403 of the Clean Water Act.
AGE, PRODUCTION, AND PROCESS PROFILE
Figure III-2 (page 529) shows the location of the eight
alumina plants operating in the United States. This figure
shows that the plants are located in the southern states and
in the U.S. Virgin Islands.
Table III-l (page 524) summarizes the relative age and discharge
status of the eight alumina plants. Most of the plants are
between 20 and 40 years old. None of the alumina plants are more
than 50 years old.
Table III-2 (page 525) lists the 1982 production ranges for
the alumina plants. Four of the eight plants produce 200,000
to 300,000 kkg/yr as aluminum contained. Two plants
produce less than 200,000 kkg/yr, and the remaining two produce
more than 400,000 kkg/yr as aluminum contained.
Table III-3 (page 526) lists the major production processes
associated with the refining of bauxite. Also shown is the
number of plants generating wastewater from these processes.
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BAUXITE REFINING SUBCATEGORY SECT-III
Table III-l
INITIAL OPERATING YEAR (RANGE) SUMMARY OF PLANTS
IN THE BAUXITE REFINING SUBCATEGORY BY DISCHARGE TYPE
Initial Operating Year - Range (Plant Age - years)
1982-
Type of 1963
Discharge (0-20)
No. of Plants
1962- 1952- 1942- Before
1953 1943 1933 1932
(20-30) (30-40) (40-50) (<50)
Total
Di rect
0
2
1
0
0
3
Indirect
0
0
0
0
0
0
Zero
1
1
2
1
0
5
TOTAL
1
3
3
1
0
8
Table II1-2
PRODUCTION FOR THE BAUXITE REFINING SUBCATEGORY
Type of
Discharge
Di rect
Indirect
Zero
Total
1
0-200
0
0
2
2
Alumina Production1 (1982)
200-300 300-400 400-600
3
0
1
4
0
0
0
0
0
0
2
2
Total
3
0
5
8
In thousands kkg/yr of contained aluminum
525
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BAUXITE REFINING SUBCATEGORY SECT-III
Table III-3
SUMMARY OF BAUXITE REFINING PROCESSES AND
ASSOCIATED WASTE STREAMS
Process No. Plants No. Plants
with Process with Wastewater
Bauxite grinding and digestion 8
-Digester condensate 4 4
Red mud removal and liquor 8
purification
-Mud impoundment effluent 3 3
Precipitation and classification 8
-Barometric condenser effluent 5 5
- Carbonation plant effluent 1 1
Calcination 8
NOTE: Through reuse or evaporation practices, a plant may
generate a wastewater from a process but not have a discharge of
that wastewater.
526
-------
BAUXITE REFINING SUBCATEGORY
SECT
- Ill
527
-------
K)
00
0-»
Ileal
Uclydge
H_0
r
p
Pr*f Ipltat Ion
O
Spent Caustic
ClassicIcatIon
Hydrate
Washing or
Flit rat l«m
LSolId Seed
LSolId Seed
Scale'By-Croduct I
lor Activated Alu- |
•Ina Production |
CO,
Barometric Condenser
Ef f I uenc
[
CalcInlng
Soluble 9alts to Disposal
Kcroveiod Sodlun Aluatnatr
Returned to l)l|teyt Ion
Hydrate
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CalcInlng
(; j It I ned AI un Ina
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Figure 111 -1 (Continued)
BAUXITE REFINING PROCESS
-------
m n*n
S 04*
L'
Oil*
l-z
Virgin Islands
Direct Process Wastewater Discharge Plants
Indirect Process Wastewater Discharge Plants
Zero Process Wastewater Discharge Plants
03
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Figure III-2
GEOGRAPHIC LOCATIONS OF THE BAUXITE REFINING SUBCATEGORY PLANTS
-------
BAUXITE REFINING SUBCATEGORY SECT-IV
SECTION IV
SUBCATEGORY ATION
This section summarizes the factors considered during the
designation of the bauxite refining subcategory and its related
subdivisions.
FACTORS CONSIDERED IN SUBCATEGORIZATION
In establishing subcategories in the nonferrous metals
manufacturing category, the following factors were
evaluated for use in determining appropriate
subcategories. These factore are discused more fully in Section
IV of Vol. 1.
1. Metal products, co-products, and by-products;
2. Raw materials;
3. Manufacturing processes;
4. Product form;
5. Plant location;
6. Plant age;
7. Plant size;
8. Air pollution control methods;
9. Meteorological conditions;
10. Treatment costs;
11. Nonwater quality aspects;
12. Njrr.ber of employees;
13. Total energy requirements; and
14. Unique plant characteristics.
Evaluation of all factors that could warrant subcategorization
resulted in the designation of the bauxite refining subcategory.
Three factors were particularly important in establishing these
classifications: the type of metal produced, the nature of the
raw materials used, and the manufacturing processes involved.
Bauxite refining was considered as a single subcategory during
the previous (1974) rulemaking (40 CFR Part 421, Subpart A).
FACTORS CONSIDERED IN SUBDIVIDING THE BAUXITE REFINING
SUBCATEGORY
The rationale for considering further subdivision of the bauxite
refining subcategory into building blocks is based primarily on
the production process used. Within this subcategory, a number
of different operations are performed, which may or may not
have a water use or discharge, and which may require the
establishment of separate effluent limitations and standards.
While bajxite refining is still considered a single
subcategory, a more thorough examination of the production
processes has illustrated the need for limitations and
531
Preceding page blank
-------
BAUXITE REFINING SUBCATEGORY SECT-IV
standards based on a specific set of waste streams. Limitations
and standards will be based on specific flow allowances for
the following subdivisions:
1. Digester condensate,
2. Barometric condenser effluent,
3. Carbonation plant effluent, and
4. Mud impoundment effluent.
OTHER FACTORS
Factors other than manufacturing processes which were considered
in this evaluation either support the establishment of the four
subdivisions or were determined to be inappropriate bases for
subdivision. Air pollution control methods, treatment costs, and
total energy requirements are functions of the selected
subcategorization factors, namely metal product, raw materials,
and production processes. Factors such as plant age, plant size,
and number of employees were also evaluated and determined to be
inappropriate bases for subdivision of this nonferrous
metals subcategory.
TYPE OF PLANT
There is fundamentally only one process for refining bauxite: the
Bayer process. The combination process, a variation of the Bayer
process, further treats the red mud waste from the Bayer process
to recover additional aluminum and alkali values. The
differences in the manufacturing processes and wastes produced at
Bayer-process plants and combination process plants are not
significant enough to warrant further subdivision based on plant
type.
RAW MATERIALS
The major process waste associated with the refining of bauxite
is the red mud residue. While the monohydrate content of
different ores requires different digestion conditions at
different plants, the quality of the red mud waste is not
significantly affected. Similarly, the differences in quality
between the red mud from the Bayer process and the brown mud
waste generated when residues from high-silica bauxites are
treated by the combination process do not warrant further
subdivis ion.
There are differences in the amount of mud generated per ton of
alumina produced which depend on the source of the bauxite. Only
one-third ton of mud is produced per ton of alumina when Surinam
bauxite is processed; two or more tons of mud are produced per
ton of bauxite when Arkansas bauxite is refined. Nevertheless,
these differences affect the size, not the nature of the disposal
532
-------
BAUXITE REFINING SUBCATEGORY SECT-IV
problem. Therefore, the specific type of bauxite raw material
refined is not chosen as a basis for further subdivision.
PLANT LOCATION
The relationship between annual rainfall and annual evaporation
is significant at bauxite refining plants because the process
facilities and red mud lakes typically cover large land areas.
In regions where precipitation exceeds evaporation, collected
rainfall runoff can accumulate and present disposal problems.
However, if provisions are made to segregate process wastewaters
and runoff from plant sites, the runoff can be discharged to its
normal water course. By allowing the discharge of net rainfall
from the impoundment areas, accumulation of water and disruption
of the plant's water balance can be avoided. Therefore, further
subdivision based on plant location is not necessary.
533
-------
BAUXITE REFINING SUBCATEGORY SECT-V
SECTION V
WATER USE AND WASTEWATER CHARACTERISTICS
This section describes the characteristics of wastewater
associated with the bauxite refining subcategory. Data used to
quantify wastewater flow and pollutant concentrations are
presented, summarized, and discussed. The contribution of
specific production processes to the overall wastewater discharge
from bauxite refining plants is identified whenever possible.
The two principal data sources were data collection portfolios
(dcp) and field sampling results. Data collection portfolios,
completed for each of the bauxite refining plants, contain
information regarding wastewater flows and production levels.
In order to quantify the pollutant discharge from bauxite
refining plants, a field sampling program was conducted.
Wastewater samples were analyzed for 124 of the 126
toxic pollutants and other pollutants deemed appropriate.
(Because the analytical standard for TCDD was judged to be too
hazardous to be made generally available, samples were never
analyzed for this pollutant. Also, samples were never
analyzed for asbestos. There is no reason to expect that TCDD
or asbestos would be present in bauxite refining
wastewater.) Two plants were selected for sampling in the
bauxite refining subcategory. A complete list of the
pollutants considered and a summary of the techniques used in
sampling and laboratory analyses are included in Section V of
the General Development Document. In general, the samples were
analyzed for three classes of pollutants: priority organic
pollutants, priority metal pollutants, and criteria
pollutants (which includes both conventional and nonconventional
pollutants).
No additional sampling was performed by EPA following
proposal. Therefore, the pollutant selection process discussed
in Section IV and the compliance cost and pollutant removal
estimates presented in Section X are based on the same data
used for proposal. EPA received several comments from
industry which provided additional wastewater characterization
data. These data were used to help EPA formulate its
recorrunendations for this subcategory.
As described in Section IV of this supplement, the bauxite
refining subcategory has been further divided into four
building blocks. Differences in the characteristics of
the wastewater streams corresponding to each subdivision are to
be expected and are addressed separately in the discussions
that follow. These wastewater sources are:
1. Digester condensate,
535
Preceding page blank
-------
BAUXITE REFINING SUBCATEGORY SECT-V
2. Barometric condenser effluent,
3. Carbonation plant effluent, and
4. Mud impoundment effluent.
WASTEWATER CHARACTERISTICS DATA
Data used to characterize the various wastewaters associated with
bauxite refining come from two sources: data collection
portfolios (dcp) and analytical data from field sampling trips.
DATA COLLECTION PORTFOLIOS
In the data collection portfolios, plants were asked to indicate
which of the priority pollutants were known or were believed to
be present in their effluent. Two plants indicated that
priority organics were known to be present. Three plants
stated that priority metals were known or believed to be
present in their effluent. The responses from the three plants
which provided information are summarized below.
Pollutant Known Present Believed Present
23.
chloroform
1
0
44.
methylene chloride
1
0
48.
dichlorobromomethane
1
0
65.
phenol
2
2
68.
di-n-butyl phthalate
1
0
70.
diethyl phthalate
1
0
86.
toluene
1
0
114.
antimony
2
2
115.
arsenic
2
3
117.
beryllium
1
1
118.
cadmium
1
2
119.
chromium (Total)
2
3
120.
copper
2
3
121.
cyanide (Total)
1
0
122.
lead
2
3
123.
mercury
2
3
124.
nickel
1
2
125.
selenium
2
3
126.
silver
2
3
127.
thallium
1
2
128.
z inc
2
3
FIELD SAMPLING DATA
In order to quantify the concentrations of pollutants present in
wastewater from bauxite refining plants, wastewater samples were
collected at two of the eight plants. Diagrams indicating the
sampling sites and contributing production processes are shown in
Figures V-l and V-2 (pages 552 to 553).
536
-------
BAUXITE REFINING SUBCATEGORY SECT-V
The sampling data for the bauxite refining subcategory are
presented in tables at the end of this section. The stream codes
listed may be used to identify the location of each of the
samples on the process flow diagrams in Figures V-l and V-2.
Where no data are listed for a specific day of sampling, the
wastewater samples for the stream were not collected.
Several points regarding these tables should be noted. First,
the data tables include some samples measured at concentrations
considered not quantifiable. The base-neutral extractable, acid
extractable, and volatile organics are generally considered not
quantifiable at concentrations equal to or less than 0.010 mg/1.
Below this concentration, organic analytical results are not
quantitatively accurate; however, the analyses are useful to
indicate the presence of a particular pollutant. The pesticide
fraction is considered not quantifiable at concentrations equal
to or less than 0.005 mg/1. Nonquantifiable results are
designated in the tables with an asterisk (double asterisk for
pesticides).
Second, the detection limits shown on the data tables are not the
same in all cases as the published detection limits for these
pollutants by the same analytical methods. The detection limits
used were reported with the analytical data and hence are the
appropriate limits to apply to the data. Detection limit
variation can occur as a result of a number of laboratory-
specific, equipment-specific, and daily operator-specific
factors. These factors can include day-to-day differences in
machine calibration, variation in stock solutions, and variation
in operators.
Third, the statistical analysis of data includes some samples
measured at concentrations considered not quantifiable.
Priority organics data reported as an asterisk or with a "less
than" sign are considered as detected but below quantifiable
concentrations, and a value of zero is used for averaging. A
value of zero is also used for averaging if a pollutant
is reported as not detected. Finally, priority metal values
reported as less than a certain value were considered as below
quantification and a value of zero is used in the calculation of
the average.
Finally, appropriate source water concentrations are presented
with the sampling data. The method by which each sample was
collected is indicated by number as follows:
1. One-time grab
2. Manual composite during intermittent process operation
3. 8-hour manual composite
4. 8-hour automatic composite
5. 24-hour manual composite
6. 24-hour automatic composite
WASTEWATER CHARACTERISTICS AND FLOWS BY BUILDING BLOCK
537
-------
BAUXITE REFINING SUBCATEGORY SECT-V
Bauxite refining involves four principal sources of wastewater,
each of which has potentially different characteristics. The
wastewater characteristics corresponding to each will be
described separately in the discussions that follow. A discharge
is allowed from the overflow of a process wastewater impoundment
in a volume equal to the difference between the precipitation
that falls within the impoundment in a given month and the
evaporation from that impoundment (this is termed net
precipitation). EPA is not promulgating any
modifications to the no discharge limitation for process
wastewater pollutants (which was originally promulgated April 8,
1974). For this reason, water use and discharge flow will
be addressed only with regard to the net precipitation
discharge from mud impoundments in the discussions that follow.
DIGESTER CONDENSATE
Bauxite ore is digested with caustic to produce a slurry of
sodium aluminate in aqueous solution with undissolved solids.
This slurry enters a system of expansion vessels or "flash tanks"
for cooling, pressure reduction, and heat recovery. Vapor
released in the flash tanks is condensed as a high quality water
suitable for reuse as boiler water or product wash water. The
digester condensate is characterized by treatable concentrations
of phenols, low concentrations of suspended solids, and high pH.
Sampling data for the digester condensate are presented in Table
V-2 (page 541).
BAROMETRIC CONDENSER EFFLUENT
The spent liquor separated from the hydrate crystals during
classification is returned to the grinding and digestion
processes to recover the caustic value of the stream. The liquor
passes through evaporators which remove excess water and re-
concentrate the caustic stream for reuse.
The vapor generated in the spent caustic evaporators is condensed
in barometric condensers. Although occasional upsets may cause
entrainment of caustic, the condensate, also referred to as
hotwell discharge, is a good quality, somewhat alkaline water.
This stream is characterized by treatable concentrations of
ph enols and suspended solids. Sampling data for barometric
condenser effluent are presented in Table V-3 (page 544).
CARBONATION PLANT EFFLUENT
Some provision must be made to remove soluble salts from the
recycled caustic to prevent the accumulation of impurities in the
process. One plant removes and carbonates a small portion of the
process liquor and the hydrate seed. The resulting alumina
precipitate is returned to the digesters. The overflow from the
carbonation process contains the soluble impurities in a
neutralized solution which is characterized by treatable
concentrations of phenols and suspended solids. Sampling data
538
-------
BAUXITE REFINING SUBCATEGORY SECT-V
for carbonation plant effluent are presented in Table V-4 (page
547).
MUD IMPOUNDMENT EFFLUENT
Red mud is the major waste stream from the bauxite refinery. It
contains all of the impurities from the bauxite, such as iron
oxide, silicon dioxide, and titanium dioxide, as well as by-
products formed during the process, such as sodium aluminum
silicates and calcium silicates. Red mud is discharged to ponds,
along with other process streams, where insoluble solids,
including the oxides of metallic elements, settle out of
suspension. The clarified liquid, characterized by treatable
concentrations of phenols and high pH, can be recycled and
reused directly from the mud lake or decanted to a "clear
lake" before discharge in accordance with the net precipitation
limitations.
The water use and discharge rates of this wastewater are listed
in Table V-l (page 540) in liters per year of mud impoundment
effluent. Sampling data for the effluent from mud
impoundments at two plants are presented in Table V-5 (page 549).
At plant A, the impoundment effluent is discharged directly
from the mud lake without recycle to the process. At plant B,
overflow and underflow from the red mud drying beds are sent to a
clear lake from which water is recycled or discharged.
539
-------
BAUXITE REFINING SUBCATEGORY
SECT-V
Table V-l
WATER USE AND DISCHARGE RATES FOR
MUD IMPOUNDMENT EFFLUENT (1/yr)
Plant Code Discharge Flow
1171 1.45 x 109
1141 5.95 x 109
1076 2.983 x 108
1136 0
1073 0
1135 0
1032 0
1015 0
540
-------
BAUXITE REFINING SUBCATEGORY SECT-V
TABLE V-2
BAUXITE REFINING SUBCATEGORY
DIGESTER CONDENSATE SAMPLING DATA
Pollutant
Stream
Sample
Concentration (mg/1)
Toxic Pollutants
Code
Type
Source
Day 1
Day 2
Da
1. acenaphthene
101
5
0. 018
0.026
0.
201
5
0.093
0.
4. benzene
201
1
*
0.140
0.
6. carbon tetrachloride
101
1
0.140
11. 1,1,1-trichloroethane
201
1
21. 2,4,6-trichlorophenol
201
5
ND
0.032
22. parachlorometacresol
201
5
ND
ND
23. chloroform
101
1
*
*
A
*
201
1
*
0.054
0.093
0.
24. 2-chlorophenol
201
5
ND
ND
31. 2,4-dichlorophenol
201
5
ND
0.011
34. 2,4-dimethylphenol
101
5
0.930
0.
201
5
*
ND
0 .420
39. fluoranthene
101
5
*
0.015
*
0.
201
5
*
*
*
44. methylene chloride
101
1
*
*
0 .018
0.
201
1
0.073
0. 020
0.
55. napthalene
101
5
0.039
0 .018
0.
201
5
0.130
*
57. 2-nitrophenol
101
5
*
201
5
ND
ND
a
0.
58. 4- nitrophenol
201
5
ND
ND
59. 2,4-dinitrophenol
201
5
ND
ND
60. 4,6-dinitro-o-cresol
101
5
0.
201
5
*
0.016
64. pentachlorophenol
101
5
*
201
5
ND
ND
65. phenol
101
5
A
1.800
2.300
1.
201
5
ND
2.100
1.30
0 .
66. bis(2-ethylhexyl)phthalate
101
5
0.790
0.066
0.055
0.
201
5
0 .020
0.053
0.
67. butyl benzyl phthalate
101
5
*
*
A
A
68. di-n-butyl phthalate
101
5
*
0.034
*
*
201
5
0.047
0 .
70. diethyl phthalate
101
5
0.015
0.016
A
201
5
0.080
0.280
0 .
71. dimethyl phthalate
101
5
0.022
0.038
541
-------
BAUXITE REFINING SUBCATEGORY SECT-V
TABLE V-2 (Continued)
BAUXITE REFINING SUBCATEGORY
DIGESTER CONDENSATE SAMPLING DATA
Pollutant Stream Sample Concentration (mg/1)
Toxic Pollutants
Code
Type
Source
Day 1
Day
73.
benzo (a)pyrene
101
5
201
5
76.
chrysene
101
5
201
5
A
77.
acenapthylene
101
5
0.030
201
5
0.05
80.
fluorene
101
5
*
0.03
B4.
pyrene
101
5
*
A
201
5
*
A
65.
tet rachlorethylene
101
1
A
201
1
0.012
A
B6.
toluene
101
1
0.02
201
1
0.053
0.34
•
r-
00
trichloroethylene
101
1
*
A
201
1
A
69.
aldrin
201
5
a *
* *
92.
4,4'-DDT
101
5
* *
* *
A A
201
5
* *
* *
A A
93.
4,4'-DDE(p,p1DDX)
101
5
* *
* *
201
5
**
* *
A A
94.
4,4'-DDD(p,p'TDE)*
101
5
97.
endosulfan sulfate
101
5
A A
201
5
* *
A A
96.
endrin
201
5
* *
A A
99.
endrin aldehyde
101
5
* *
A A
201
5
* *
* *
A A
101.
heptachlor epoxide
101
5
**
a*
201
5
* *
* *
A A
102.
alpha-BHC
101
5
104.
gamina-BHC
101
5
* *
* *
201
5
* *
A A
A A
105.
delta-BHC
201
5
A A
106.
PCB-1242 (Arochlor
1242)
101
5
A *
A A
201
5
A A
A A
A A
107.
PCB-1254 (Arochlor
1254 )
101
5
* *
A A
201
5
A A
A A
A A
108.
PCB-1221 (Arochlor
1221)
101
5
A *
A A
A A
201
5
* *
A A
A A
109.
PCB-1232 (Arochlor
1232)
101
5
* *
A A
201
5
* *
A A
A A
0
0
542
-------
BAUXITE REFINING SUBCATEGORY SECT-V
TABLE V-2 (Continued)
BAUXITE REFINING SUBCATEGORY
DIGESTER CONDENSATE SAMPLING DATA
Pollutant Stream Sample Concentration (mg/1)
Toxic
Pollutants
Code
Type
Source
Day 1
Day 2
Da
110.
PCB-1248 (Arochlor 1248)
101
5
**
**
*
201
5
**
* *
* *
*
111.
PCB-1260 (Arochlor 1260)
101
5
* *
**
*
201
5
* *
* *
* *
*
112.
PCB-1016 (Arochlor 1016)
101
5
* *
**
*
201
5
* *
* *
* *
*
114.
antimony
101
5
<0.1
<0.1
<0.1
<0 .
201
5
<0.1
<0.1
<0.1
115.
arsenic
101
5
<0.01
<0.01
<0.01
<0.
201
5
<0.01
<0.01
0.03
121.
cyanide (Total)
101
1
0.002
<0.001
0 .
201
1
0.002
<0 . 001
0 .
125.
selenium
101
5
<0.01
<0.01
<0.01
<0 .
201
5
<0.01
<0.01
<0.01
126.
silver
101
5
<0.2
<0.2
<0.2
<0 .
201
5
<0.2
<0.2
<0 . 2
127 .
thallium
101
5
<0.1
<0.1
<0.1
<0 .
201
5
<0.1
<0.1
<0.1
Nonconventional Pollutants
Chemical oxygen demand (COD)
101
5
39
131
158
139
201
5
24
229
214
167
chlor ide
101
5
8.
fluoride
101
5
0 .
phenols (4-AAP)
101
5
7.19
7 .
201
5
6.05
6 .
Conventional Pollutants
oil a
nd grease
101
1
31
11
1
201
1
7
5
5
total
suspended solids (TSS)
101
5
768
6
5
6
101
5
277
11
2
14
pH (s
td. units)
101
5
9.10
9.71
9.
201
5
9.85
9 . 55
9.
NOTES:
Sample type code
1 - One time Grab
2 - 24-hour manua"
composite
* Less than 0.01 mg/1
** Less than 0.005 mg/1
(a), (b) - Reported together
543
-------
BAUXITE REFINING SUBCATEGORY
SECT-V
TABLE V-3
BAUXITE REFINING SUBCATEGORY
BAROMETRIC CONDENSER (HOT WELL) DISCHARGE
RAW WASTEWATER SAMPLING DATA
Pollutant Stream Sample Concentration (mg/1)
Toxic Pollutants
Code
Type
Source
Day 1
Day 2
Da
1. acenaphthene
102
5
A
A
202
6
A
A
4. benzene
202
1
*
*
A
10. 1,2,dichloroethane
102
1
*
A
20. 2-chloronaphthalene
202
6
A
21. 2, 4,6-trichlorophenol
202
6
ND
0.032
22. parachlorometacresol
102
5
0.013
202
6
ND
ND
23. chloroform
102
1
*
*
0.
202
1
*
*
A
A
24. 2-chlorophenol
202
6
ND
*
31. 2,4-dichlorophenol
202
6
A
0.010
34. 2,4-dimethylphenol
102
5
0.038
202
6
*
39. fluoranthene
102
5
*
A
f
A
202
6
A
44. methylene chloride
102
1
*
0.063
0.
202
1
0.110
A
55. napthalene
202
6
A
57. 2-nitrophenol
102
5
0.110
A
202
6
A
A
58. 4- nitrophenol
201
5
ND
ND
A
59. 2,4-dinitrophenol
202
6
ND
ND
60. 4,6-dinitro-o-cresol
202
6
A
0.019
64. pentachlorophenol
202
6
ND
ND
65. phenol
102
5
*
0.075
202
6
ND
2.0
A
A
66. bis(2-ethylhexyl)phthalate
102
5
0.790
0. 170
0.016
0.
202
6
0.020
*
1.3
0.
67. butyl benzyl phthalate
102
5
*
A
A
202
6
A
68. di-n-butyl phthalate
102
5
*
A
A
202
6
*
0. 016
A
70. diethyl phthalate
101
5
A
A
201
6
*
A
71. dimethyl phthalate
102
5
A
202
6
0.011
A
544
-------
BAUXITE REFINING SUBCATEGORY SECT-V
TABLE V-3
BAUXITE REFINING SUBCATEGORY
BAROMETRIC CONDENSER (HOT WELL) DISCHARGE
RAW WASTEWATER SAMPLING DATA
Pollutant Stream Sample Concentration (mg/1)
Toxic Pollutants
Code
Type
Source
Day 1
Day 2
Da
73.
benzo (a)pyrene
102
5
*
76.
chrysene
202
6
*
77.
acenapthylene
102
5
*
*
201
6
*
*
•
o
00
fluorene
102
5
*
*
202
6
*
*
00
pyrene
202
6
*
*
202
5
85.
tetrachlorethylene
102
1
*
202
1
*
86.
toluene
102
1
*
*
202
1
*
89.
aldrin
202
6
* *
* *
* *
*
90.
dieldrin
102
5
* *
* *
*
202
6
* *
*
91.
chlorodane
102
5
* *
* *
*
202
6
* *
* *
~ *
~
92.
4,4'-DDT
102
5
* *
~ *
*
202
6
* *
* *
~ *
*
93.
4,4'-DDE(p,p'DDX)
101
5
* *
* *
*
202
5
*
94.
4,4'-DDD(p,p'TDE)*
102
5
* *
202
6
**
* *
97 .
endosulfan sulfate
102
5
* *
202
6
* *
* *
*
98.
endrin
102
5
* *
*
202
6
* *
* *
~
99.
endrin aldehyde
202
6
* *
* *
100.
heptachlor
102
5
* A
*
202
6
* *
* *
*
101.
heptachlor epoxide
101
5
* *
* *
*
201
5
* *
* *
* *
*
102.
alpha-BHC
102
5
*
202
6
* *
* *
*
103 .
beta-BHC
102
5
* *
~ *
*
202
6
~ *
* *
~ *
*
104 .
garrjTia—BHC
102
5
~ *
~ *
*
202
6
~ *
~ *
* *
*
105 .
delta-BHC
202
6
* *
* *
* *
*
545
-------
BAUXITE REFINING SUBCATEGORY SECT-V
TABLE V-3 {Continued)
BAUXITE REFINING SUBCATEGORY
{ BAROMETRIC CONDENSER (HOT WELL) DISCHARGE
• RAW WASTEWATER SAMPLING DATA
i
i Pollutant Stream Sample Concentration (mg/1)
Toxic Pollutants
Code
Type
Source
Day 1 Day 2 D
* *
106
. PCB-1242 (Arochlor 1242)
102
5
* *
202
6
* *
* * * *
107
. PCB-1254 (Arochlor 1254)
102
5
**
* *
202
6
* *
* * A A
108
. PCB-1221 (Arochlor 1221)
102
5
* *
* A
202
6
a a
A A A A
109
. PCB-1232 (Arochlor 1232)
102
5
**
A A
202
6
* *
A A A A
110
. PCB-1248 (Arochlor 1248)
102
5
* *
A A
202
6
* *
A A A A
111
. PCB-1260 (Arochlor 1260)
102
5
**
A A
202
6
* *
A A A A
112
. PCB-1016 (Arochlor 1016)
102
5
* *
A A
202
6
* *
A A A A
121
. cyanide (Total)
101
1
201
1
Nonconventional Pollutants
Chemical oxygen demand (COD)
102
5
39
36 36 50
202
6
24
31 28 30
chloride
102
5
20
fluor ide
101
5
0
phenols (4-AAP)
101
1
ND
0.374 0.190 0
201
1
ND
0.020 0.023
Conventional Pollutants
oil
and grease
101
1
ND
10 9 2
201
1
ND
5 4 4
total suspended solids (TSS)
101
5
768
373 275 270
101
5
277
296 462 291
pH
(std. units)
101
5
8.70 9.12 9
201
5
8.0 8.2
NOTES:
Sample type code
1 - One time Grab
*
Less than 0.01 mg/1
5 - 24-hour manual composite
**Less than
0.005 mg/1
6 - 24-hour automatic composite
(a)
, (b) -
Reported together
546
-------
BAUXITE REFININ.G SUBCATEGORY SECT-V
TABLE V-4
BAUXITE REFINING SUBCATEGORY
CARBONATION PLANT EFFLUENT
RAW WASTEWATER SAMPLING DATA
Pollutant Stream Sample Concentration (mg/1)
Toxic Pollutants Code Type Source Day 1 Day 2 Da
21. 2,4,6-trichlorophenol
201
5
ND
ND
22. parachlorometacresol
201
5
ND
ND
23. chloroform
203
1
*
*
0.054
24. 2-chlorophenol
203
5
ND
1.600
31. 2,4-dichlorophenol
203
5
ND
ND
34. 2,4-dimethylphenol
203
5
*
ND
0.140
39. fluoranthene
203
5
*
44. methylene chloride
203
1
*
57. 2-nitrophenol
203
5
ND
ND
58. 4- nitrophenol
203
5
ND
ND
59. 2,4-dinitrophenol
203
5
ND
ND
60. 4,6-dinitro-o-cresol
203
5
*
ND
64. pentachlorophenol
203
5
ND
ND
1.300
65. phenol
203
5
ND
2.100
0.016
66. bis(2-ethylhexylJphthalate
203
5
0.020
67. butyl benzyl phthalate
203
5
*
68. di-n-butyl phthalate
203
5
*
70. diethyl phthalate
203
5
0.017
71. dimethyl phthalate
203
5
0.011
0.130
77. acenapthylene
203
5
*
84. pyrene
203
5
*
85. tetrachlorethylene
203
1
0.021
87. trichloroethylene
203
1
*
89. aldrin
203
5
**
* *
90. dieldrin
203
5
**
91. chlorodane
203
5
* *
* *
93. 4,4'-DDE(p,p'DDX)
203
5
* *
A *
96. beta-endosulfan
203
5
* *
97. endosulfan sulfate
203
5
* *
100. heptachlor
203
5
* *
* *
101. heptachlor epoxide
203
5
* *
* *
103. beta-BHC
203
5
* *
* *
104. gamma-BHC
203
5
* *
* *
547
-------
BAUXITE REFINING SUBCATEGORY
SECT-V
TABLE V-4
BAUXITE REFINING DIGESTER CONDENSATE
SAMPLING DATA
Pollutant
Stream Sample
Toxic Pollutants
Code
Type
Source
Day
105.
delta-BHC
203
5
* *
106.
PCB-1242
(Arochlor
1242 )
a
203
5
* *
107.
PCB-1254
(Arochlor
1254)
a
203
5
**
108.
PCB-1221
(Arochlor
1221)
a
203
5
* *
109.
PCB-1232
(Arochlor
1232)
b
203
5
* A
110.
PCB-1248
(Arochlor
1248)
b
203
5
* A
111.
PCB-1260
(Arochlor
1260)
b
203
5
* *
112.
PCB-1016
(Arochlor
1016)
b
203
5
* *
114.
antimony
203
5
<0.1
<0.1
115.
arsenic
203
5
<0.01
0.44
121.
cyanide
(Total)
203
1
<0. 00
125.
selenium
203
5
<0.01
<0.01
126.
silver
203
5
<0.02
0.02
127.
thallium
203
5
<0.1
0.3
Concentration (mg/1)
Day 2_ Da
Nonconventional Pollutants
Chemical oxygen demand (COD)
phenols (4-AAP)
Conventional Pollutants
203 5 24 8,270 3,985
203 5 24.6 11.2
oil and grease 203 1
total suspended solids (TSS) 203 5
pH (std. units) 203 5
43 9
277 325 887
7.9 8.6
NOTES:
Sample type code
1 - One time Grab
2 - 24-hour manual composite
* Less than 0.01 mg/1
** Less than 0.005 mg/1
(a), (b) - Reported together
548
-------
BAUXITE REFINING SUBCATEGORY SECT-V
TABLE V-5
BAUXITE REFINING SUBCATEGORY
MUD LAKE DISCHARGE
RAW WASTEWATER SAMPLING DATA
Pollutant Stream Sample Concentration (mg/1)
Toxic Pollutants
Code
Type
Source
Day 1
Day 2
Da
1. acenaphthene
101
5
*
6. carbon tetrachloride
201
1
*
10. 1p2-dichlorethane
104
1
*
21. 2,4,6-trichlorophenol
104
5
0.048
0.
204
6
ND
*
0.054
22. parachlorometacresol
204
1
ND
ND
23. chloroform
104
1
*
0.026
*
N
204
1
*
0.015
0.
24. 2-chlorophenol
204
6
ND
0.065
0.
31. 2,4-dichlorophenol
104
5
0.050
0.047
0.
204
6
*
0.060
34. 2,4-dimethylphenol
104
5
*
• *
204
6
*
*
39. fluoranthene
104
5
*
*
204
6
*
*
*
44. methylene chloride
104
1
*
0.051
*
204
1
0.020
0.
48. dichlorobromomethane
204
1
*
55. napthalene
204
6
*
0.
57. 2-nitrophenol
104
5
*
204
6
ND
ND
0.067
58. 4- nitrophenol
104
5
0.040
0.
204
6
ND
ND
0.310
59. 2,4-dinitrophenol
204
4
ND
ND
60. 4,6-dinitro-o-cresol
204
4
*
0.011
64. pentachlorophenol
104
5
*
204
6
ND
ND
65. phenol
104
5
*
0.034
0.035
0.
204
6
ND
0.320
0.230
0.
66. bis(2-ethylhexylJphthalate
104
5
0.790
0.150
0.330
*
204
6
0 . 020
0.720
0.650
*
67. butyl benzyl phthalate
104
5
*
*
*
*
204
6
*
*
68. di-n-butyl phthalate
104
5
*
*
*
*
204
6
*
*
*
*
70. diethyl phthalate
204
5
0.011
0 . 010
0.
71. dimethyl phthalate
104
5
*
204
6
1.
549
-------
BAUXITE REFINING SUBCATEGORY SECT-V
TABLE V-5
BAUXITE REFINING SUBCATEGORY
MUD LAKE DISCHARGE
RAW WASTEWATER SAMPLING DATA
Pollutant
Toxic Pollutants
Code
Type
77.
acenapthylene
104
5
204
6
80.
fluorene
104
5
84.
pyrene
104
5
204
6
85.
tetrachlorethylene
104
1
86.
toluene
204
1
91.
Cholordane
201
5
204
6
92.
4,4'-DDT
104
5
204
6
93.
4,4'-DDE(p,p'DDX)
204
6
95.
alpha-endosulfan
104
5
96.
beta-endosulfan
104
5
97.
endosulfan sulfate
104
5
204
6
98.
endrin
104
5
204
6
99.
endrin aldehyde
204
6
100.
heptachlor
104
5
204
6
101.
heptachlor epoxide
104
5
204
6
102
alpha-BHC
104
5
204
6
103.
beta-BHC
104
5
204
6
104.
gamma-BHC
101
5
204
6
106.
PCB-1242 (Arochlor
1242)
a
101
5
204
6
107 .
PCB-1254 (Arochlor
1254 )
a
101
5
204
6
108.
PCB-12 21 (Arochlor
1221)
a
104
5
204
6
109.
PCB-1232 (Arochlor
1232 )
b
104
5
204
6
110.
PCB-1248 (Arochlor
1248)
b
104
5
204
6
Stream Sample Concentration (mg/1)
Source Day 1 Day 2 Da
* 0.
0.
0.012
* *
* *
* *
* *
* *
* *
* A
* *
**
550
-------
BAUXITE REFINING SUBCATEGORY SECT-V
TABLE V-5 (Continued)
BAUXITE REFINING SUBCATEGORY
MUD LAKE DISCHARGE
RAW WASTEWATER SAMPLING DATA
Pollutant Stream Sample Concentration (mg/1)
Toxic Pollutants Code Type Source Day 1_ Day 2_ Da
111. PCB-1260 (Arochlor 1260)
b
104
5
**
**
* *
204
6
A*
**
* *
*
112. PCB-1016 (Arochlor 1016)
b
104
5
**
**
* *
204
6
**
**
* *
*
114. antimony
104
5
<0.1
<0.1
<0.1
<0 .
204
6
<0.1
<0.1
<0.1
115. arsenic
104
5
<0.01
0.2
0.14
0.
204
6
<0.01
0.32
0.08
121. cyanide (Total)
104
1
0.01
0.003
0.
204
1
<0.001
<0.001
<0.
125. selenium
104
5
<0.01
<0 .01
<0.01
A
o
»
204
6
<0.01
<0.01
<0.01
126. silver
104
5
<0.02
<0.02
<0.02
<0.
204
6
<0.02
<0.02
<0. 02
127. thallium
104
5
<0.1
<0.1
<0.1
<0.
204
6
<0.1
<0.1
<0.1
<0.
Nonconventional Pollutants
Chemical oxygen demand (COD)
101
5
39
364
374
451
201
5
24
977
943
495
chlor ide
101
5
33
fluoride
101
5
4
201
5
2
phenols (4-AAP)
101
5
0.197
0.116
0.
201
5
0.981
1.15
1.
Conventional Pollutants
oil and grease
101
1
23
5
201
1
15
6
22
total suspended solids (TSS)
101
5
768
18
16
9
101
5
277
11
2
4
pH (std. units)
101
5
11.70
11.76
11 .
201
5
11. 55
11 . 5
NOTES:
Sample type code * Less than 0.01 mg/1
1 - One time Grab ** Less than 0.005 mg/1
2 - 24-hour manual composite (a) or (b) - Reported together
551
-------
BAUXITE REFINING SUBCATEGORY SECT
b y
u u
* a
a e
-------
~
Ln
Ln
u>
Klvei WJlei
(C]
h2h
Ka In
Red Hud
Mu.1 Drying
Clear l.ake
Wastes
Beds
Excels
(Mgeuter
Ondensat e
BaruiueirIt
Condenser
Ef f lueiit
a
—0—
CO,
Fli AJ justinent
Disc liar
h®-
Discharge
Recycle lo Process
-*¦ Dl scliarge
w
>
c
>>:
M
t-3
n
s
55
O
in
C
W
O
>
t-3
m
o
o
ro
~<
I' I ant
l.lquor
CO
C'jrbonar Ion
Plant
Ik 1 sc lid r g*.-
cn
m
0
h
1
<
Sol Ills lo Process
Figure V-2
SAMPLING SITES AT BAUXITE REFINING PLANT B
-------
BAUXITE REFINING SUBCATEGORY SECT-VI
SECTION VI
SELECTION OF POLLUTANT PARAMETERS
Section V of this supplement presented data from bauxite refining
plant sampling visits and subsequent chemical analyses. This
section examines that data and discusses the selection or
exclusion of pollutants for potential limitation.
This section discusses the selection of conventional and
nonconventional pollutants for consideration for regulation. The
discussion that follows also describes the analysis that was
performed to select or exclude priority pollutants for
further consideration for limitations and standards. Generally,
pollutants will be selected for further consideration if
they are present in concentrations treatable by the
technologies considered in this analysis. The treatable
concentrations used for the toxic metals are the long-term
treatment performance concentrations achievable by lime
precipitation, sedimentation, and filtration (L,S&F).
The concentrations for the toxic organics are the
long-term performance values achievable by activated carbon
adsorpt ion.
CONVENTIONAL AND NONCONVENTIONAL POLLUTANT PARAMETERS
This study considered samples from the bauxite refining
subcategory for three conventional pollutant parameters (oil and
grease, total suspended solids, and pH) and two nonconventional
pollutant parameters (chemical oxygen demand and total
phenolics). Because existing BPT regulations (40 CFR Part 421,
Subpart A) specify zero discharge of process wastewater
pollutants, only sampling data from allowable net
precipitation discharges from mud impoundments were considered
in the selection of conventional and nonconventional pollutant
parameters for regulation.
CONVENTIONAL AND NONCONVENTIONAL POLLUTANT PARAMETERS SELECTED
The conventional and nonconventional pollutants or pollutant
parameters selected for consideration for limitation in this
subcategory are pH and phenols.
The pH values observed in five samples ranged from 11.5 to 11.76.
Effective and consistent removal of priority organics by
activated carbon or chemical oxidation requires careful
control of pH. Therefore, pH is selected for consideration for
limitation in this subcategory.
Phenols concentrations in six samples ranged from 0.116 to 1.23
555
Preceding page blank
-------
BAUXITE REFINING SUBCATEGORY SECT-VI
mg/1. The observed concentrations are above those considered
treatable by identified treatment technology. Sampling data from
process wastewater streams, presented in Section V, indicate the
presence of phenolic compounds throughout the bauxite refining
process. Therefore, phenols are considered for limitation in
this subcategory.
The major source of oil and grease in the bauxite refining
subcategory is from the lubrication of process machinery.
Because oil and grease in process wastewater is not present in
significant concentrations, oil and grease is not selected for
limitation.
Total suspended solids (TSS) concentrations in six samples range
from 2 to 18 mg/1. Although treatable, these concentrations are
not considered to be significant and are not expected to
interfere with end-of-pipe treatment technologies such as
activated carbon adsorption or chemical oxidation. Therefore,
total suspended solids are not selected for limitation in the
bauxite refining subcategory.
TOXIC PRIORITY POLLUTANTS
The frequency of occurrence of the toxic pollutants in
the wastewater samples taken is presented in Table VI-1 (page
561). These data provide the basis for the categorization
of specific pollutants, as discussed below. Table VI-1 is based
on the raw wastewater data from mud impoundment effluents at
plant A and plant B (see Section V). All other wastewaters
have existing zero discharge regulations and were therefore
not considered here. Treatment plant and source water
samples were not considered in this frequency count.
TOXIC POLLUTANTS NEVER DETECTED
The toxic pollutants listed in Table VI-2 (page 565) were either
not analyzed or not detected in any wastewater samples from
this subcategory; therefore, they are not selected for
consideration in establishing regulations:
We did not analyze for selected pollutants in samples of
raw wastewater from this subcategory. These pollutants are
not believed to be present based on the Agency's best
engineering judgment which includes consideration of raw
materials and process operations.
TOXIC POLLUTANTS NEVER FOUND ABOVE THEIR ANALYTICAL
QUANTIFICATION LEVEL
The toxic pollutants listed in Table VI-3 (page 567) were never
found above their analytical quantification concentration in
any wastewater samples from this subcategory; therefore,
they are not selected for consideration in establishing
556
-------
BAUXITE REFINING SUBCATEGORY SECT-VI
regulations.
TOXIC POLLUTANTS PRESENT BELOW CONCENTRATIONS ACHIEVABLE BY
TREATMENT
The pollutants listed below are not selected for consideration in
establishing limitations because they were not found in any
wastewater samples from this subcategory above concentrations
considered achievable by existing or available treatment
technologies.
115. arsenic
127. thallium
Arsenic was detected above its analytical quantification limit in
five of five samples from two plants. These samples were below
the 0.34 mg/1 concentration considered achievable by treatment.
Therefore, arsenic is not selected for limitation.
Thallium was detected above its analytical quantification limit
in one of five samples from two plants. This sample was below
the 0.34 mg/1 concentration considered achievable by identified
treatment technology. Therefore, thallium is not selected for
limitation.
TOXIC POLLUTANTS DETECTED IN A SMALL NUMBER OF SOURCES
The following pollutants were not selected for limitation because
they were detected in only a small number of sources:
23. chloroform
44. methylene chloride
55. naphthalene
60. 4,6-dinitro-o-cresol
66. bis(2-ethylhexyl) phthalate
68. di-n-butyl phthalate
70. diethyl phthalate
71. dimethyl phthalate
77. acenaphthylene
85. tetrachloroethylene
Although these pollutants were not selected for
establishing nationwide limitations, it may be
case-by-case basis, for the local permitter to
limitations.
consideration in
appropriate, on a
specify effluent
Chloroform was detected above its treatable limit in three of six
samples from two plants at concentrations of 0.015, 0.026, and
0.063 mg/1. This pollutant is not attributable to any source
within the refinery. It also appears in the source water and it
is commonly used in the analytical laboratories as a solvent.
For these reasons chloroform is not considered for limitation.
Methylene chloride was found above its treatable concentration in
557
-------
BAUXITE REFINING SUBCATEGORY SECT-VI
three of four samples from two plants at concentrations of 0.020,
0.051, and 0.170 mg/1. This pollutant is not attributable to
specific materials or processes associated with bauxite refining.
It is, however, a common solvent used in analytical laboratories.
Since the possibility of sample contamination is likely,
methylene chloride is not selected for limitation.
Naphthalene was detected above its treatable concentration in one
of two samples from one plant, at a concentration of 0.02 mg/1.
This pollutant is not attributable to bauxite refining operations
or raw materials; it is also present only slightly above the
treatability concentration. For these reasons, naphthalene is
not considered for limitation.
4,6-Dinitro-o-cresol was found above its treatability
concentration in one sample from one plant, at a concentration of
0.011 mg/1. Because this pollutant is not attributable to any
specific materials or processes in the bauxite refining
operation, and it is present only slightly above the treatability
concentration of 0.01 mg/1, this pollutant is not selected for
limitation.
Bis(2-ethylhexyl) phthalate was found above its treatable
concentration of 0.01 mg/1 in five of six samples from two
plants. This compound is a plasticizer commonly used in
laboratory and field sampling equipment and is not used as a raw
material or formed as a by-product in this subcategory.
Therefore, bis|2-ethylhexyl) phthalate is not selected for
limitation.
Di-n-butyl phthalate was found above its treatable concentration
of 0.01 mg/1 in one of six samples from two plants. This
compound is a plasticizer commonly used in laboratory and field
sampling equipment and is not used as a raw material or formed as
a by-product in this subcategory. Therefore, di-n-butyl
phthalate is not selected for limitation.
Diethyl phthalate was found above its treatable concentration of
0.01 mg/1 in one of two samples from one plant. This compound is
a plasticizer commonly used in laboratory and field sampling
equipment and is not used as a raw material or formed as a by-
product in this subcategory. Therefore, diethyl phthalate is not
selected for limitation.
Dimethyl phthalate was found above its treatable concentration in
one of two samples from two plants at a concentration of 1.5
mg/1. This pollutant is not attributable to specific materials
or processes associated with bauxite refining. The high
concentration is probably due to contamination from laboratory
equipment. Therefore, dimethyl phthalate is not selected for
limitation.
Acenaphthylene was found above its analytical quantification
limit in two of three samples from two plants at concentrations
of 0.018 and 0.086 mg/1. This pollutant has been shown to be
558
-------
BAUXITE REFINING SUBCATEGORY SECT-VI
present in the wastewater from briquette quenching operations in
the primary aluminum subcategory. The two sampled plants are
integrated facilities which manufacture a number of aluminum-
based products. Therefore, because it is likely to be generated
by processes outside the bauxite refining subcategory and because
it is not specifically attributable to the bauxite refining
process, acenaphthylene is not selected for limitation.
Tetrachloroethylene was found above its treatability limit in one
sample from one plant, at a concentration of 0.012 mg/1. This
pollutant is not attributable to any process or material in the
refining process; it is present only slightly above its
treatability concentration of 0.01 mg/1 and it is frequently used
in the laboratory, where contamination could occur. For these
reasons, tetrachloroethylene is not selected for limitation.
TOXIC POLLUTANTS SELECTED FOR FURTHER CONSIDERATION FOR
LIMITATION
The toxic pollutants listed below are selected for
further consideration in establishing limitations for this
subcategory. The selected pollutants are discussed individually
following the list.
21. 2,4,6-trichlorophenol
24. 2-chlorophenol
31. 2,4-dichlorophenol
57. 2-nitrophenol
58. 4-nitrophenol
65. phenol
2,4,6-Trichlorophenol was found above its analytical
quantification limit in three of four samples from two plants
with concentrations ranging from 0.048 to 0.072 mg/1. All three
of those samples were above the 0.01 mg/1 concentration
considered achievable by identified treatment technology.
Therefore, 2,4,6-trichlorophenol is selected for further
consideration for limitation.
2-Chlorophenol was found above its analytical quantification
limit in two of two samples from one plant with concentrations of
0.065 and 0.720 mg/1. Both of those samples were above the 0.01
mg/1 treatability concentration. Therefore, 2-chlorophenol
is selected for further consideration for limitation.
2,4-Dichlorophenol was found above its analytical quantification
limit in four of five samples from two plants with concentrations
ranging from 0.047 to 0.060 mg/1. All four of those samples were
above the 0.01 mg/1 treatability concentration. Therefore, 2,4-
dichlorophenol is selected for further consideration for
limitation.
2-Nitrophenol was found above its analytical quantification limit
in one of three samples from two plants at a concentration of
0.067 mg/1. That sample was above the 0.01 mg/1 treatability
559
-------
BAUXITE REFINING SUBCATEGORY SECT-VI
concentration. Therefore, 2-nitrophenol is selected for further
consideration for limitation.
4-Nitrophenol was found above its analytical quantification limit
in three of four samples from two plants with concentrations
ranging from 0.017 to 0.310 mg/1. Those three samples were above
the 0.01 mg/1 treatability concentration. Therefore, 4-
nitrophenol is selected for further consideration for limitation.
Phenol was found above its analytical quantification limit in six
of six samples from two plants with concentrations ranging from
0.034 to 0.750 mg/1. All six of those samples were above the
0.01 mg/1 treatability concentration. Also, phenols have been
identified as constituents of bauxite ore. Therefore, phenol is
selected for further consideration for limitation.
560
-------
Table VI-1
FREQUENCY OF OCCURRENCE OF PRIORITY POLLUTANTS
BAUXITE REFINING
RAW WASTEWATER
(_n
cr>
Po11 iifant^
I. acenaphthone
7. acrolein
5. ar.ry lonl fr I le
4. ben/ene
¦>. hnn/ldlne
6. carbon tetrachloride
I. chloroben/nne
0. I,7,4-trIchlorobenzene
•i. hexschlorobcniene
10. I,7-dlchloroethane
11. I,I,l-trIchloroethene
I?, hexachloroethane
15. 1, l-dlchloroothaim
14. I,I,7-trIchloroethane
1^. I,I,2,2-tetrachloroethane
16. chloroethane
W. bl s(chlortmefliy I) ether
IB. bl sl?-cliloroothy I) ether
19. 7-chloroelhyI vinyl ethor
70. 7-chloronaphthalone
71. 7,4,6-trIchlorophenol
77. parachlorotnnta ciesol
7). chloroform
74. ?-chlorophenol
7^. I,7-dlchlorobeniene
76. I, J-d I ch I orobenf ene
?'. I,4-dlchloroben/ene
79. 5,5,-dlchlorohen/ldlne
?<>. I,l-
G
X
M
•-3
M
»
M
25
O
to
C
OT
O
>
•-3
M
O
O
»
K
to
a
o
1-3
-------
Table V1—1 (Continued)
FREQUENCY OF OCCURRENCE OF PRIORITY POLLUTANTS
BAUXITE REFINING
RAW WASTEWATER
LTl
CTl
fsj
55.
56.
W.
58.
59.
40.
11.
« £ .
15.
44 .
n.
46.
4/.
4ft.
4<).
•>o.
>l .
'.5.
•>4.
•>6.
V.
>8.
">9.
f.O.
l>l.
(>?.
(.5.
t>4.
1.6.
Acialyl leal
Iroat able
Detected
Detected
Quant 11IcatIon
Concentra-
Number of
Number ol
Detected Relou
He low treat-
Above Treat-
Concentrat Ion
~ Ion
Streams
Samples
Quant 11IcatIon
able Concen-
able Concen-
Pol I lit an t
(mq/11(a)
Analyzed
Analyzed
NO
Concentrat Ion
trat Ion
tration
i ,4 — (11 n 1 trntolllrtlie
0.010
0.01
? ,6-dl n| fro toluene
0.010
0.01
1,?-d1pheny1 hydra;1ne
0.010
0.01
ethylhen/ene
0.010
0.01
1luor anthene
0.010
0.01
2
4
4
4-chloi ophenyl phenyl ether
0.010
0.01
4-brcmopheny1 phenyl ether
0.010
0.01
hi •, 1 ?-chloroi sopr opy 1 ) uthor
0.010
0.01
blr,(? chloroethn»y1 melhane
0.010
0.01
mnthylene chloride
0.010
0.01
2
4
1
*
•nnlliyl chloride
O.OiO
0.01
methyl bromide
0.010
0.01
bromolorm
0.010
0.01
d 1 c h 1 or ohr omome t hane
0.010
0.01
1
1
1
tr Ichlor of luorumHthane
0.010
0.01
d 1 c h 1 or nd 11 1 uoi nme t h Ann
0.010
0.01
rh lorodl bromnmot hane
0.010
0.01
hntfrichloi obutadlene
0.010
0.01
tiexach lorocyc 1 open tail 1 ene
0.010
0.01
1 sophni one
0.010
0.01
naph t ha 1ene
0.010
0.01
1
2
1
1
nltroben/ene
0.010
0.01
/-n1trophonol
0.010
0.01
7
5
1
1
1
4-nllr ophenol
0.010
0.01
2
4
1
5
? , 4-d 1 n 11 r (tptiftnol
0.010
0.01
1
1
1
4 ,6-dlnl tro-o-cresol
0.010
0.01
1
1
N-n 1 ti osod Imnt hy 1 ami no
0.010
0.01
N-n 1 lro',od 1 pheny 1 ami nn
0.010
0.01
N-n 1 tryvxl 1 - n-« pi op / 1 ami ne
0.010
0.01
pont acti 1 or ophAno 1
0.010
0.01
2
2
1
1
phono1
0.010
0.01
2
6
6
his(X-ethy 1hnvy1> phthalate
0.010
0.01
2
6
1
•)
CO
>
G
X
M
H
M
W
55
O
yi
G
CO
o
>
H
W
O
O
K
11
M
(
K
-------
Table Vl-1 (Continued)
FREQUENCY OF OCCURRENCE OF PRIORITY POLLUTANTS
BAUXITE REFINING
RAW WASTEWATER
Ln
CT\
u>
AnalytIral
Treatable
Detected
Detected
Quant 11IcatIon
Concentra-
Nunber of
Number of
Detectod Below
Below Treat-
Above Treat-
ConcenlratIon
t Ion
Streams
Soxp1es
Quanl1tIcatIon
able Coiicen-
able Concen-
Pollutant
(mq/lH a)
0.010
(atq/ 1Mb)
Analyzed
Analyzed
NO
Concentrat Ion
tratIon
tratIon
67. butyl benzyl phthalate
0.01
2
5
5
68. <1t-n-b«tyl phthalate
0.010
0.01
2
5
4
1
69. dl-n-octyl phthalate
0.010
0.01
1
/(). diethyl phthalate
0.010
0.01
1
2
71. dlmothyl phthalate
0.010
0.01
2
2
1
1
72. henztil alanthr scene
0.010
0.01
H. benzolalpyreno
0.010
0.01
74. S,4-benio. tntr achloroethylene
0.010
0.01
1
1
86. lolueno
0.010
0.01
1
1
1
87. trIchloroethylene
0.010
0.01
88. vinyl chloride
0.010
0.01
89. aldi In
0.005
0.01
90. dloldrln
0.005
0.01
91. chlordane
0.005
0.01
2
5
5
9?. 4,4'-l»>I
0.005
0.01
2
6
6
9S. 4 ,4 1 -not
0.005
0.01
1
1
1
94. 4,4,-linO
0.005
0.01
95. alpha-endotul 1»"
96. bnta-riMo^til l«h
0.005
0.01
1
2
2
0.005
0.01
1
2
2
97. endosullan sulfate
0.005
0.01
2
5
5
98. endrln
0.005
0.01
2
4
4
99. endrIn aldehyde
0.005
0.01
1
1
1
100. hnptachlfH"
0.005
0.01
2
6
6
101. heptachlor epoxide
0.005
0.01
2
6
6
CO
>
G
X
M
t-3
M
»
w
55
Q
1/5
G
CO
o
>
w
Q
O
»
K
1/5
n
o
-------
Table Vl-1 (Continued)
FREQUENCY OF OCCURRENCE OF PRIORITY POLLUTANTS
BAUXITE REFINING
RAW WASTEWATER
LP
(T>
Analytleal
Treatable
Detected
Quant 1fleaf Ion
CorHen t ra-
Nu»b«r ot
Number of Detected He low
Be loo treat-
ConcentratIon
t Ion
Streams
Samples Quantification
able Concen-
Pol
lutant
(nq/IHal
(mq/IHbl
Analysed
Analyzed NO Concentration
tration
102.
alpha-BHC
0.005
0.01
2
) )
10).
bofa-HHC
0.005
0.01
7
6 6
104.
gamnwi-HHC
0.005
0.01
7
4 4
105.
delta-BHC
0.005
0.01
106.
PC8-I742
(dl
0.005
0.01
2
5 5
107.
PCB-1754
(dl
0.005
0.01
2
5 5
108.
PCH-I77I
(d)
0.005
0.01
2
5 5
109.
PCO-I2J7
le)
0.005
0.01
2
5 5
110.
PCO-1248
(el
0.005
0.01
2
5 5
III.
PUI-1760
(el
0.005
0.01
2
5 5
117.
PCU-I0I6
(el
0.005
0.01
2
5 5
II).
toxaphene
0.005
0.01
114.
antImony
0.100
0.47
2
5 5
115.
arsenic
0.010
0.)4
2
5
5
116.
asbestos
117.
ber y 1 111*»
0.010
0.70
118.
cadmium
0.002
0.049
119.
Chroml in
0.005
0.07
170.
copper
0.009
0. }9
171.
cyanide
(fl
0.02
0.047
2
6 6
172.
lead
0.020
0.08
I? J.
mercury
0.0001
0.0)6
174.
nickel
0.005
0.27
175.
selenlm
0.01
0.70
2
5 5
126.
s11ver
0.07
0.07
2
5 5
177.
tlial 11 if*
0.100
0.)4
2
5 4
1
178.
/Inc
0.050
0.2)
179.
2,),7,8-tetrachlorodlben*o-
p-dloxliy tICUOI-
(a)
Analytleal
quantification concentration was reported with the data (see Section VI.
(b)
Truafable
concentrations are
based on performance ol line preelp
tat Ion, sed 1m
intatlon, and filtration.
Detected
Above treat-
able Coocen-
tralIon
td
>
c
X
M
t-3
PI
»
M
*1
s:
o
t/>
c
Cd
n
>
i-3
PI
O
O
JO
K
W
PI
n
(c>, (d), («> Reported together.
(•) Analytical quantification concentration lor H'A HBthod 51^.2, total Cyanide Methods for Chemical Analysis of Water and Wastes, IPA 600/4-/9-070,
M.irrh n;q.
-------
BAUXITE REFINING SUBCATEGORY SECT-VI
TABLE VI-2
TOXIC POLLUTANTS NEVER DETECTED
2. acrolein*
3. acrylonitrile*
4. benzene*
5. benzidene*
7. chlorobenzene*
8. 1,2,4-trichlorobenzene*
9. hexachlorobenzene*
10. 1,2-dichloroethane*
11. 1,1,1-trichloroethane*
12. hexachloroethane*
13. 1,1-dichloroethane*
14. 1,1,2-trichloroethane*
15. 1,1,2,2-tetrachloroethane*
16. chloroethane*
17. bis (chloromethyl) ether (deleted)*
18. bis (2-chloroethy1) ether*
19. 2-chloroethyl vinyl ether (mixed)*
20. 2-chloronaphthalene*
22. parachlorometa cresol
25. 1,2-dichlorobenzene*
26. 1,3-dichlorobenzene*
27. 1,4-dichlorobenzene*
28. 3,3'-dichlorobenzidine*
29. 1,1-dichloroethylene*
30. 1,2-trans-dichloroethylene*
32. 1,2-dichloropropane*
33. 1,2-dichloropropylene (1,3-dichloropropene)*
35. 2,4-dinitrotoluene*
36. 2,6-dinitrotoluene*
37. 1,2-diphenylhydrazine*
30. ethylbenzene*
40. 4-chlorophenyl phenyl ether*
41. 4-bromophenyl phenyl ether*
42. bis(2-chloroisopropyl) ether*
43. bis(2-choroethoxy ) methane*
45. methyl chloride (chloromethane)*
46. methyl bromide {bromomethane)*
47. bromoform (tribromomethane)*
49. trichlorofluoromethane (deleted)*
50. dichlorodifluoromethane (deleted)*
51. chlorodibromomethane*
52- hexachlorobutadiene*
53. hexachlorocyclopentadiene*
54. isophorone*
56. nitrobenzene*
59. 2,4-dinitrophenol
61. N-nitrosodimethylamine*
62. N-nitrosodiphenylamine*
63. N-nitrosodi-n-propylamine*
69. di-n-octyl phthalate*
565
-------
BAUXITE REPINING SUBCATEGORY SECT-VI
TABLE VI-3
PRIORITY POLLUTANTS NEVER FOUND ABOVE THEIR
ANALYTICAL QUANTIFICATION LEVEL
1. acenaphthene
6. carbon tetrachloride (tetrachloromethane)
34. 2,4-dimethylphenol
39. fluoranthene
48. dichlorobromomethane
64. pentachlorophenol
67. butyl benzyl phthalate
80. fluorene
84. pyrene
86. toluene
91. chlordane (technical mixture and metabolites)
92. 4,4'-DDT
93. 4,4'-DDE(p,p1DDX)
95. a-endosulfan-Alpha
96. b-endosulfan-Beta
97. endosulfan sulfate
98. endrin
99. endrin aldehyde
100. heptachlor
101. heptachlor epoxide
102. alpha-BHC
103. beta-BHC
104. r-BHC (lindane)-Gamma
106. PCB-1242 (Arochlor 1242)
107. PCB-1254 (Arochlor 1254)
108. PCB-1221 (Arochlor 1221)
109. PCB-1232 (Arochlor 1232)
110. PCB-12 48 (Arochlor 1248)
111. PCB-1260 (Arochlor 1260)
112. PCB-1016 (Arochlor 1016)
114. antimony
121. cyanide (Total)
125. selenium
126. silver
567
-------
BAUXITE REFINING SUBCATEGORY SECT-VII
SECTION VII
CONTROL AND TREATMENT TECHNOLOGIES
The preceding sections of this supplement discussed the sources,
flows, and characteristics of the wastewaters generated in the
bauxite refining subcategory. This section summarizes the
description of these wastewaters and indicates the level of
treatment which is currently practiced for each waste stream.
CURRENT CONTROL AND TREATMENT PRACTICES
Control and treatment technologies are discussed in general in
Section VII of the General Development Document. The basic
principles . of these technologies and the applicability to
wastewater similar to that found in this subcategory are
presented there. This section presents a summary of the control
and treatment technologies that are currently applied to each of
the sources generating wastewater in this subcategory. As
discussed in Section V, wastewater associated with the bauxite
refining subcategory is characterized by the presence of
treatable concentrations of phenolic compounds and high pH. This
analysis is supported by the raw (untreated) wastewater data
presented for specific sources in Section V. According to
promulgated BPT limitations (40 CFR Part 421, Subpart A), the
only allowable discharge of wastewater pollutants for the bauxite
refining subcategory is the net precipitation discharge from
the red mud impoundment. The other three subdivisions
(digester condensate, barometric condenser effluent, and
carbonation plant effluent) are all restricted to zero discharge
of wastewater pollutants under the promulgated BPT regulation.
Three plants in this subcategory currently discharge treated
water from the mud impoundment area. One option has been
selected for consideration for BPT, BAT, NSPS, and pretreatment
based on this waste stream.
MUD IMPOUNDMENT EFFLUENT
Red mud is the major waste stream from bauxite refining
operations. It contains the impurities from the bauxite ore as
well as by-products formed during the refining process. Red mud
is deposited in large ponds where insoluble solids, including the
oxides of metallic elements, settle out of suspension. Rainfall
from the plant site is often routed to the mud impoundment.
Water from the impoundment can be recycled to the plant directly
from the mud lake or it can be decanted to a separate clear lake
before recycle.
Three plants currently discharge water from the mud impoundment.
At one plant, water is discharged after pH adjustment without
recycle to the process. At another plant, a portion of the water
569
-------
BAUXITE REFINING SUBCATEGORY SECT-VII
which is recycled to the plant from a clear lake is discharged
without treatment. The third plant discharges excess stormwater
from closed mud lakes after pH adjustment. The remaining five
plants in this subcategory currently achieve zero discharge by
permanent lagoon impoundment and partial recycle. However, one
of these plants is considering a process technology change which
would result in a mud impoundment discharge.
CONTROL AND TREATMENT OPTIONS
Although the existing limitations are not being modified, the
Agency examined one control and treatment alternative that is
applicable to the bauxite refining subcategory to generate
the guidance limitations. The option selected for evaluation
represents an end-of-pipe treatment technology.
OPTION E
Option E for the bauxite refining subcategory consisted of
all control requirements of the existing BPT (no discharge of
process wastewater pollutants, and discharge of net
precipitation from process wastewater impoundments) plus pH
adjustment and activated carbon adsorption treatment of the
mud impoundment effluent. Activated carbon adsorption is used
to remove organic compounds, including phenolics, from the
effluent wastewater. Adjustment of pH is required to ensure
consistent removal performance by adsorption and to meet
discharge quality standards.
The Agency also considered the use of pH adjustment and chemical
oxidation to remove phenolic compounds from the effluent
wastewater. Adjustment of pH is required to ensure consistent
discharge quality standards. Hydrogen peroxide is suggested
for the oxidation of phenols, but other chemicals, such as
chlorine dioxide and ozone, may perform satisfactorily.
570
-------
BAUXITE REFINING SUBCATEGORY SECT-VIII
SECTION VIII
COSTS OF WASTEWATER TREATMENT AND CONTROL
The Agency is not revising the promulgated regulation for
discharges from bauxite refining. Therefore there are no costs
associated with this rulemaking. This section describes the
method used to develop the costs associated with the guidance
control and treatment technologies of Option E discussed in
Section VII for wastewaters from bauxite refining plants. Plant-
by-plant compliance costs for this option were developed.
Compliance costs for chemical oxidation were also estimated.
The energy requirements of the considered option as well as
solid waste and air pollution aspects are also discussed. The
General Development Document provides background on the
capital and annual costs for the technology discussed herein
and the methodology used to develop compliance costs.
TREATMENT OPTIONS COSTED FOR EXISTING SOURCES
As discussed in Section VII, one treatment option has been
considered for existing bauxite refining plants. This option is
summarized below and is schematically presented in Figure X-l
(page 582).
OPTION E
Option E consists of the BPT requirements with additional control
of the mud impoundment discharges by pH adjustment and activated
carbon adsorption. The Agency also prepared capital and annual
costs for pH adjustment and chemical oxidation of the mud
impoundment effluent at one median plant. The calculated costs
were much higher in relation to the costs for activated carbon at
the same plant, therefore, no further consideration was given to
this technology.
COST METHODOLOGY
Plant-by-plant compliance costs have been estimated for this
subcategory. The costs for the option in this subcategory are
presented in Table VIII-1 (page 573). The major assumptions specific
bauxite refining subcategory are discussed briefly below.
(1) The Option E treatment system consists of pH adjustment
followed by carbon adsorption. The flows were determined from
information provided in the dcp for red mud impoundment
discharge flow only. The influent concentrations for phenol
and 2-chlorophenol were determined from averages of field
sampling data from two plants. These data are found in Table V-5
(page 549).
(2) Costs for pH adjustment were based on reduction of pH from
571
-------
BAUXITE REFINING SUBCATEGORY SECT-VIII
11.5 to 9 using sulfuric acid.
(3) The carbon exhaustion rate was determined from adsorption
isotherms for phenol and 2-chlorophenol, influent concentrations
from the sampling data, and an effluent concentration in both
cases of 0.010 mg/1. Using this procedure and an excess of 50
percent to account for other adsorbable organics, a carbon
exhaustion rate of 2.321 lbs/1000 gallons was determined.
(4) Plants 1076 and 1141 have pH adjustment equipment in place;
capital cost estimates are included for all other equipment at
the three discharging plants and the one existing zero discharger
who is considering a discharge.
NONWATER QUALITY ASPECTS
Nonwater quality impacts specific to the bauxite refining
subcategory, including energy requirements, solid waste and
air pollution are discussed below.
ENERGY REQUIREMENTS
Energy requirements for Option E are estimated at 11,500,000
kwh/yr. This represents less than 3 percent of the total
energy usage of the four plants. It is therefore concluded that
the energy requirements of the treatment option considered will
not have a significant impact on total plant energy
consumpt ion.
SOLID WASTE
No significant amounts of solid wastes are generated by the
technologies considered for this regulation in the bauxite
refining subcategory. Activated carbon is thermally regenerated
either on-site or off-site, and in neither case are appreciable
quantities of solid waste generated.
AIR POLLUTION
There is no reason to believe that any substantial air pollution
problems will result from implementation of activated carbon
treatment and pH adjustment. Thermal regeneration of spent
carbon may release trace quantities of pollutants, but these
should be readily oxidized at the temperatures under which the
carbon is regenerated.
572
-------
BAUXITE REFINING SUBCATEGORY SECT-VIII
Table VIII-1
COST OF COMPLIANCE FOR THE BAUXITE REFINING SUBCATEGORY
DIRECT DISCHARGERS*
(March, 1982 Dollars)
Opt ion
E
Proposal
Total Required
Capital Cost
Total
Annual Cost
7,600,000
2,980,000
*Include
process
s one plant currently practicing
wastewater.
zero discharge
-------
BAUXITE REFINING SUBCATEGORY SECT-IX
SECTION IX
BEST PRACTICABLE TECHNOLOGY CURRENTLY AVAILABLE
BPT limitations for the bauxite refining subcategory were
promulgated on April 8, 1974 as Subpart A of 40 CFR Part 421.
EPA is not amending these BPT limitations which are reproduced
below.
The following limitations establish the quantity or quality of
pollutants or pollutant properties which may be discharged by a
point source after application of the best practicable control
technology currently available: There shall be no discharge
of process wastewater pollutants to navigable waters.
During any calendar month, there may be discharged from the
overflow of a process wastewater impoundment either a volume of
wastewater equal to the difference between the precipitation for
that month that falls within the impoundment and the evaporation
within the impoundment for that month, or, if greater, a volume
of process wastewater equal to the difference between the mean
precipitation for that month that falls within the impoundment
and the mean evaporation for that month as established by the
National Climatic Center, National Oceanic and Atmospheric
Administration, for the area in which such impoundment is located
(or as otherwise determined if no monthly data have been
established by the National Climatic Center).
The data gathered since the original promulgation do not warrant
any adjustment in the BPT requirements. Minor amendments to
the regulatory language are being promulgated to clarify
references to fundamentally different factors (FDF)
considerations under 40 CFR Part 125 and
references to pretreatment standards under 40 CFR Part 128.
As a result, the bauxite refining subcategory will not incur
any incremental capital or annual costs to comply with the BPT
1imi tat ions.
575
-------
BAUXITE REFINING SUBCATEGORY SECT-X
SECTION X
BEST AVAILABLE TECHNOLOGY ECONOMICALLY ACHIEVABLE
These effluent limitations are based on the best control and
treatment technology used by a specific point source
within the industrial category or subcategory, or by
another industry where it is readily transferable.
Emphasis is placed on additional treatment techniques
applied at the end of the treatment systems currently used, as
well as reduction of the amount of water used and
discharged, process control, and treatment technology
optimization.
The factors considered in assessing best available technology
economically achievable (BAT) include the age of equipment and
facilities involved, the process used, process changes, nonwater
quality environmental impacts (including energy requirements),
and the costs of application of such technology (Section
304(b)(2)(B) of the Clean Water Act). At a minimum, BAT
represents the best available technology economically achievable
at plants of various ages, sizes, processes, or other
characteristics. Where the Agency has found the existing
performance to be uniformly inadequate, BAT may be transferred
from a different subcategory or category. BAT may include
feasible process changes or internal controls, even when not in
common industry practice.
The required assessment of BAT considers costs, but does not
require a balancing of costs against effluent reduction benefits
However, in assessing BAT, the Agency has given substantial
weight to the economic achievability of the technology.
TECHNICAL APPROACH TO BAT
In pursuing this second round of effluent limitations, the Agency
reviewed a wide range of technology options and evaluated the
available possibilities to ensure that the most effective and
beneficial technologies were used as the basis of BAT. To
accomplish this, the Agency elected to examine one technology
option which could be applied to the bauxite refining subcategory
as an alternative for the basis of BAT effluent limitations. The
treatment technology considered for BAT is summarized below:
Option E (Figure X-l page 582):
o Zero discharge of process wastewater pollutants
o Discharge of net precipitation from process wastewater
impoundments
577
-------
BAUXITE REFINING SUBCATEGORY SECT-X
o pH adjustment
o Activated carbon adsorption
OPTION E
Option E consists of the existing BPT requirements (no discharge
of process wastewater pollutants, discharge of net precipitation
from a process wastewater impoundment), with pH adjustment and
activated carbon adsorption treatment of the net precipitation
discharge. Activated carbon technology is used to remove toxic
organic compounds, including phenolics, from the effluent
wastewater. Adjustment of pH is required to ensure consistent
removal performance by adsorption and to meet discharge quality
standards.
INDUSTRY COST AND POLLUTANT REMOVAL ESTIMATES
As one means of evaluating the technology option, EPA developed
estimates of the pollutant removal estimates and the associated
compliance costs. The methodologies are described below.
POLLUTANT REMOVAL ESTIMATES
Sampling data collected during the field sampling program
were used to characterize the pollutant concentrations in
the waste stream considered for regulation. This information was
used with the wastewater discharge rates measured during
sampling or derived from each dcp to estimate the mass of toxic
pollutants generated by each plant in the bauxite refining
subcategory. The mass of pollutant discharged was estimated by
multiplying the achievable concentration values attainable by
the option (mg/1) by the estimated volume of wastewater
discharged by each plant in the subcategory. The mass of
pollutant removed, referred to as the benefit, is simply the
difference between the estimated mass of pollutant generated by
each plant and the mass of pollutant discharged after
application of the treatment option. The total subcategory
removal was then estimated by summing the individual plant
removal estimates for each pollutant. The pollutant
removal estimates for the bauxite refining subcategory are
presented in Table X-l (page 580).
COMPLIANCE COSTS
Based on information collected after proposal, the Agency
believes that no further revisions to the promulgated BAT
limitations are necessary. As a result, the bauxite refining
subcategory will not incur any incremental capital or annual
costs to comply with the BAT limitations. However, EPA
calculated compliance costs for the bauxite refining
subcategory by developing a wastewater treatment system design
and cost estimation model that estimates capital and annual costs
for the treatment option being considered for guidance.
This model was applied to each plant's flow and pollutant
578
-------
BAUXITE REFINING SUBCATEGORY SECT-X
characteristics, and the
calculated capital and annual costs
were summed to arrive at total subcategory costs,
which are presented in Table X-2 (page 583),
EPA's economic impact analysis.
These costs,
were used in
BAT OPTION SELECTION
EPA promulgated BAT limitations for
subcategory on April 8, 1974 as Subpart A of
These limitations allow no discharge of
pollutants to navigable waters. A discharge
overflow of a process wastewater impoundment
the net precipitation that falls within the
not promulgating any modification to these
time. At proposal, EPA was considering the
effluent limitations based on pH
activated carbon adsorption treatment of
pollutants in the mud impoundment overflow
the bauxite refining
40 CFR Part 421.
process wastewater
is allowed from the
in a volume equal to
impoundment. EPA is
limitations at this
establishment of
adjustment and
toxic organic
This revision
was in keeping with the emphasis of the Clean Water Act of 1977
on toxic pollutants.
Implementation of this organics control option would have
removed annually an estimated 4,835 kg of priority pollutants
from the raw discharge. Estimated capital cost for achieving
this option would have been $7.60 million, with estimated
annualized costs of $2.98 million.
ability
Although
category
for organics removal,
and steel manufacturing
influent characteristics
for both categories, and
are used, similar removals
Activated carbon was being considered because of its
to remove toxic organics to very low concentrations,
no plants in the nonferrous metals manufacturing
have installed this technology
it is demonstrated in the iron
category. EPA believes that the
are similar with respect to organics
that, if proper design procedures
will be achieved. Activated carbon will remove adsorbable
organics to essentially nondetectable levels if sufficient
carbon and contact time are provided. These design parameters
have been carefully and conservatively selected by EPA for
this subcategory. Therefore, based on these considerations and
the performance data from iron and steel manufacturing a
level of 0.010 mg/1 for phenol, 2-chlorophenol, and total
phenols (4-AAP) can be achieved. The Agency solicited
comments on the costs and performance of activated carbon,
and the applicabi1ity of these effluent limitations to the
bauxite refining subcategory.
Commenters on the proposal provided recently collect
their red mud lakes showing levels below the limit o
for all phenolic compounds except phenol,
indicates tha~ EPA may have overestimated
in the net precipitation discharge from
Based on these data, EPA has decided not
(pH adjustment, activated carbon adsorption) as the
basis of BAT. EPA has determined that the presence
The new da
the amounts
bauxite red
to promulga
ed data from
f detection
ta submitted
of phenols
mud lakes,
te Option E
technology
of phenols
579
-------
BAUXITE REFINING SUBCATEGORY SECT-X
may be site-specific and not common to all bauxite manufacturers.
Furthermore, EPA's analysis showed no harmful effects on
aquatic life, and only some taste and odcr effects. EPA is not
modifying the existing BAT regulation for the bauxite refining
subcategory. However, EPA is publishing limitations, shown at
the end of this section, as guidance for permitting
authorities to deal with any site-specific high levels of
phenolic compounds.
REGULATED POLLUTANT PARAMETERS
The raw wastewater concentrations from individual operations and
the subcategory as a whole were examined to select certain
pollutants and pollutant parameters for limitation. This
examination and evaluation, presented in Section VI,
concluded that six pollutants and pollutant parameters
are present in bauxite refining wastewaters at concentrations
that can be reduced by identified treatment technologies.
The high cost associated with analysis for priority
organic pollutants had prompted EPA to consider an alternative
method for regulating and monitoring pollutant discharges from
the nonferrous metals manufacturing category. Rather than
developing specific effluent limitations and standards for each
of the organics pollutant found in treatable concentrations in
the raw wastewater from a given subcategory, the Agency was
considering effluent limitations only for those pollutants
generated in the greatest quantities as shown by the pollutant
removal estimate analysis. On this basis, the pollutants
recommended for specific limitation at proposal are listed below:
24. 2-chlorophenol
65. phenol
By recommending limitations and standards for certain
priority organic pollutants, dischargers would attain the same
degree of control over priority organic pollutants as they
would have been required to achieve had all the priority
organic pollutants been directly limited. This approach is
technically justified because the design of activated carbon
columns must consider the presence of other organic compounds
which will be removed from the wastewater. Even though
the removal of different phenolic compounds will occur at
different rates, treatment of the above listed organics to
the concentration values attainable by the option will be
accompanied by a reduction in concentration of the unregulated
organics. One nonconventiona1 pollutant parameter, total
phenols (4-AAP), was being considered for limitation to ensure
adequate removal of phenolics other than 2-chlorophenol and
phenol. No priority metal pollutants were selected for specific
limitation in this subcategory.
The following priority pollutants were not being considered
for specific limitation at proposal on the basis that they
would be effectively controlled by the limitations
580
-------
BAUXITE REFINING SUBCATEGORY SECT-X
recommended for 2-chlorophenol, phenol, and total phenols (4-
AAP) :
21. 2,4,6-trichlorophenol
31. 2,4-dichlorophenol
57. 2-nitrophenol
58. 4-nitrophenol
The conventional pollutant parameter pH may be limited by the
best conventional technology (BCT) effluent limitations.
EFFLUENT LIMITATIONS
The concentrations achievable by application of pH adjustment and
activated carbon are discussed in Section VII of the General
Development Document. The recommended effluent limitations
for mud impoundment effluent are shown below. These
effluent limitations are presented as guidance for state or local
pollution control agencies for case-by-case control of
phenolics.
RECOMMENDED GUIDANCE FOR BAT EFFLUENT LIMITATIONS
FOR THE BAUXITE REFINING SUBCATEGORY
Mud Impoundment Effluent
Pollutant or Maximum for
Pollutant Property Any One Day (mg/1)
2,4,6-trichlorophenol 0.010
2-Chlorophenol 0.010
2,4-dichlorophenol 0.010
4-nitrophenol 0.010
Phenol 0.010
Total Phenols (4-AAP) 0.010
581
-------
BAUXITE REFINING SUBCATEGORY SECT-X
TABLE X-l
POLLUTANT REMOVAL ESTIMATES
BAUXITE REFINING
(Direct Dischargers* - kg/yr)
Pollutant
Total Raw
Current
Discharged
Removed
2-chlorophenol
phenol
3,125.51
1,868.95
Total toxic organics 4,994.45
3,125.51
1,868.95
4,994.45
0
0
Option E
2-chlorophenol
phenol
Total toxic organics
79. 53
79. 53
159.06
3,045.98
1,789.42
4,835.40
* Includes one small plant currently practicing zero discharge of
process wastewater.
582
-------
BAUXITE REFINING SUBCATEGORY SECT-X
Table X-2
COST OF COMPLIANCE FOR THE BAUXITE REFINING SUBCATEGORY
Direct Dischargers*
Proposal Capital Cost Annual Cost
Option (1982 Dollars) (1982 Dollars)
7,600,000 2,980,000
*Includes one small plant currently practicing zero discharge
process wastewater.
583
-------
U1
00
Hud 1 HpoundiMnt El fluent
pH
MjultMDt
Activated
Carbon
AdaorpCloti
Diacharge
CO
>
G
X
M
W
73
W
"d
S5
Q
CO
C
a
O
>
H
W
a
o
jo
k
cn
M
o
h3
X
Figure X-1
OPTION E TREATMENT SCHEME FOK THE BAUXITE REFINING SUBCATEGORY
-------
BAUXITE REFINING SUBCATEGORY SECT-XI
SECTION XI
NEW SOURCE PERFORMANCE STANDARDS
The basis for new source performance standards (NSPS) under
Section 306 of the Act is the best available demonstrated
technology (BDT). New plants have the opportunity to design the
best and most efficient production processes and wastewater
treatment technologies without facing the added costs and
restrictions encountered in retrofitting an existing plant.
Therefore, Congress directed EPA to consider the best
demonstrated process changes, in-plant controls, and end-of-pipe
treatment technologies which reduce pollution to the maximum
extent feasible.
This section- describes the technologies for treatment of
wastewater from new sources and presents the performance
standards recommended as guidance for NSPS in the bauxite
refining subcategory, based on the selected treatment technology.
TECHNICAL APPROACH TO NSPS
EPA promulgated new source performance standards for the bauxite
refining subcategory on April 8 1974. The technology basis for
this promulgation was identical to BAT. EPA is promulgating
only minor technical amendments to the promulgated regulation.
It is also recommending as guidance the limitations described
in the previous section for BAT, i.e., pH adjustment and
activated carbon adsorption of mud impoundment overflow.
This result is a consequence of careful review by the Agency
of a wide range of technology options for new source
treatment systems which is discussed in Section XI of the
General Development Document. Additionally, there was nothing
found to indicate that the wastewater flows and characteristics
of new plants would not be similar to those from existing
plants, since the processes used by new sources are not expected
to differ from those used at existing sources.
The treatment technology considered for the NSPS guidance
option is identical to the treatment technology considered for
the BAT guidance option. This option is:
OPTION E
o Zero discharge of process wastewater pollutant
o Discharge of net precipitation from process wastewater
impoundments
o pH adjustment
o Activated carbon adsorption
585
-------
BAUXITE REFINING SUBCATEGORY SECT-XI
NSPS OPTION SELECTION
As discussed earlier, with the exception of minor technica
amendments, the Agency is not modifying the existing promulgate*
regulation for the bauxite refining subcategory. The Agency ii
recommending the standards presented at the end of this sectior
as guidance for permitting authorities to deal with any site-
specific high levels of phenolic compounds.
REGULATED POLLUTANT PARAMETERS
The Agency has no reason to believe that the pollutants that will
be found in treatable concentrations in processes within new
sources will be any different than with existing sources.
Accordingly, pollutants and pollutant parameters being
recommended for limitation as guidance under NSPS, in
accordance with the rationale of Sections VI and X, are identical
to those being recommended for BAT. The conventional
pollutant parameter pH is also being recommended as guidance
for limitation. For NSPS, the Agency is recommending as
guidance pH limitations for mud impoundment effluent within the
range of 7.5 to 10.0 at all times.
NEW SOURCE PERFORMANCE STANDARDS
The modified performance standards being recommended as
guidance based on pH adjustment and activated carbon adsorption
technology are listed below.
RECOMMENDED GUIDANCE FOR NSPS FOR THE BAUXITE REFINING
SUBCATEGORY
Mud Impoundment Effluent
Pollutant or Maxirr.jm for
Pollutant Property Any One Day (mg/1)
2,4,6-trichlorophenol 0.010
2-Chlorophenol 0.010
2,4-dichlorophenol 0.010
4-nitrophenol 0.010
Phenol 0.010
Total Phenols (4-AAP) 0.010
586
-------
BAUXITE REFINING SUBCATEGORY SECT-XII
SECTION XII
PRETREATMENT STANDARDS
EPA is not promulgating pretreatment standards Cor existing
sources at this time because there are currently no indirect
discharging facilities in this subcategory.
EPA promulgated PSNS for the bauxite refining subcategory on
April 8, 1974 as Subpart A of 40 CFR Part 421. The following
limitations establish the quantity or quality of pollutants or
pollutant properties which may be discharged by a new indirect
discharger: There shall be no discharge of process wastewater
pollutants to navigable waters.
During any calendar month, there may be discharged from the
overflow of a process wastewater impoundment either a volume of
wastewater equal to the difference between the precipitation for
that month that falls within the impoundment and the evaporation
within the impoundment for that month, or, if greater, a volume
of process wastewater equal to the difference between the mean
precipitation for that month that falls within the impoundment
and the mean evaporation for that month as established by the
National Clim .tic Center, National Oceanic and Atmospheric
Administration, for the area in which such impoundment is located
(or as otherwise determined if no monthly data have been
established by the National Climatic Center).
EPA is not promulgating any modifications to PSNS since it
is unlikely that any new bauxite sources will be constructed
as indirect dischargers.
-------
BAUXITE REFINING SUBCATEGORY SECT-XIII
SECTION XIII
BEST CONVENTIONAL POLLUTANT CONTROL TECHNOLOGY
EPA is not promulgating best conventional pollutant
control technology (BCT) limitations for the bauxite refining
subcategory at this time.
589
-------
NONFERROUS METALS MANUFACTURING POINT SOURCE CATEGORY
DEVELOPMENT DOCUMENT SUPPLEMENT
for the
Primary Aluminum Smelting Subcategory
William K. Reilly
Administrator
Rebecca Hanmer
Acting Assistant Administrator for Water
Martha Prothro, Director
Office of Water Regulations and Standards
si
(sez)
Thomas P. O'Farrell, Director
Industrial Technology Division
Ernst P. Hall, P.E., Chief
Metals Industry Branch
and
Technical Project Officer
May 1989
U.S. Environmental Protection Agency
Office of Water
Office of Water Regulations and Standards
Industrial Technology Division
Washington, D. C. 20460
591
-------
PRIMARY ALUMINUM SUBCATEGORY
TABLE OF CONTENTS
Sect ion Page
I SUMMARY AND CONCLUSIONS 603
II RECOMMENDATIONS 607
III INDUSTRY PROFILE 627
Description of Primary Aluminum Production 627
Raw Materials 627
Electrolytic Aluminum Production 627
Reduction Cells 627
Aluminum Fluxing and Degassing 630
Casting 632
Anode Paste Plant 633
Anode Bake Plant 635
Cathode Reprocessing 635
Procecess Wastewater Sources 636
Other Wastewater Sources 636
Age, Production, and Process Profile 637
IV SUBCATEGORIZATION 643
Factors Considered in Subdividing the 643
Primary Aluminum Subcategory
Other Factors 643
Type of Anode 643
Plant Size 644
Plant Age 644
Product 644
Production Normalizing Parameters 644
Anode and Cathode Paste Plant Wet Air 645
Pollution Control
Cathode Reprocessing 641
Potline, Potline SO2, and Potroom Wet Air 645
Pollution Control
V WATER USE AND WASTEWATER CHARACTERISTICS 649
Wastewater Sources, Discharge Rates, and 650
Characteristics
Anode and Cathode Paste Plant Wet Air 652
Pollution Control
Anode Bake Plant Wet Air Pollution Control 653
Anode and Briquette Contact Cooling 653
Cathode Reprocessing 653
Potline Wet Air Pollution Control 654
593
-------
PRIMARY ALUMINUM SUBCATEGORY
TABLE OF CONTENTS (Continued)
Section Page
V Potline SO2 Wet Air Pollution Control 654
(Cont'd) Potroom Wet Air Pollution Control 654
Degassing Wet Air Pollution Control 654
Pot Repair And Pot Soaking 655
Casting Contact Cooling Water 655
Pilot Scale Wastewater Treatment Study 656
PAH Treatment 656
Cyanide Treatment 657
VI SELECTION OF POLLUTANT PARAMETERS 72 5
Conventional And Nonconventional Pollutant 725
Parameters
Conventional And Nonconventional Pollutants 726
Parameters Selected
Toxic Pollutants 726
Toxic Pollutants Never Detected 727
Toxic Pollutants Never Found Above Their 727
Analytical Quantification Level
Toxic Pollutants Present Below Concentrations 727
Achievable By Treatment
Toxic Pollutants Detected In a Small Number 727
Of Sources
Toxic Pollutants Selected For Further 730
Consideration For Limitations
VII CONTROL AND TREATMENT TECHNOLOGIES 743
Technical Basis Of BPT 743
Current Control And Treatment Practices 743
Anode And Cathode Paste Wet Air Pollution 744
Cont rol
Anode Bake Plant Wet Air Pollution Control 744
Anode And Briquette Contact Cooling 745
Cathode Reprocessing 745
Potline And Potroom Wet Air Pollution Control 745
Pot Repair And Pot Soaking 747
Degassing Wet Air Pollution Control 747
Casting Contact Cooling 748
Control And Treatment Options 748
Option A 749
Option B 749
Option C 749
Option E 750
Control And Treatment Options Rejected 750
Fluoride Treatment Effectiveness Analysis 750
Treatment Effectiveness Analysis For Potline 750
Srubbers And Cathode Reprocessing Wastewiters
594
-------
PRIMARY ALUMINUM SUBCATEGORY
TABLE OF CONTENTS (Continued)
Sect ion Page
VIII COSTS, ENERGY, AND NONWATER QUALITY ASPECTS 7 53
Levels Of Treatment Considered 753
Option A 753
Option B 753
Option C 754
Option E 754
Cost Methodology 754
Nonwater Quality Aspects 755
Energy Requirements 755
Solid Waste 755
Air Pollution 756
IX BEST PRACTICABLE TECHNOLOGY CURRENTLY AVAILABLE 759
X BEST AVAILABLE TECHNOLOGY ECONOMICALLY 761
ACHIEVABLE
Technical Approach To BAT 761
Option A 762
Option B 763
Recycle of Anode and Casting Contact Cooling 763
Water Through Cooling Towers
Recycle of Water Used in Wet Air Pollution 764
Control
Option C 764
Op tion E 764
Industry Cost And Pollutant Removal Estimates 764
Pollutant Removal Eestimate 764
Compliance Costs 766
BAT Option Selection 766
Final Amendments To The Regulation 767
Treatment Performance 768
Wastewater Discharge Rates 770
Anode And Cathode Paste Plant Wet Air Pollution 771
Control Wastewater
Anode Bake Plant Wet Air Pollution Control 771
Wastewater
Anode Contact Cooling And Briquette Quenching 772
Water
Cathode Manufacturing 773
Cathode Reprocessing 773
Potline Wet Air Pollution Control Wastewater 774
Potline SO2 Wet Air Pollution Control 775
Potroom Wet Air Pollution Control Wastewater 775
595
-------
PRIMARY ALUMINUM SUBCATEGORY
TABLE OF CONTENTS (Continued)
Section Page
X Pot Repair And Pot Soaking 776
(Cont'd) Degassing Wet Air Pollution Control 777
Direct Chill Casting Contact Cooling 777
Continuous Rod Casting Contact Cooling 777
Statuonary Casting Contact Cooling 778
Shot Casting Contact Cooling 778
Regulated Pollutant Parameters 778
Effluent Limitations 781
XI NEW SOURCE PERFORMANCE STANDARDS 881
Technical Approach To BDT 813
Option A 813
Option B 813
Option C 814
Option E 814
BDT Option Selection 814
Regulated Pollutant Parameters 816
New Source Performance Standards 816
XII PRETREATMENT STANDARDS 83 5
Technical Approach To Pretreatment 835
Pretreatment Standards For Existing Sources 836
Pretreatment Standards For New Sources 836
Option A 836
Option B 836
Option C 837
Option E 837
PSNS Option Selection 837
Regulated Pollutant Parameters 837
Pretreatment Standards 838
XIII BEST CONVENTIONAL POLLUTANT CONTROL TECHNOLOGY 855
596
-------
PRIMARY ALUMINUM SUBCATEGORY
LIST OF TABLES
Table Title Page
III-l Initial Operating Years (Range) Summary of 638
Plants in the Primary Aluminum Subcategory
by Discharge Type
III-2 Production Ranges for the Primary Aluminum 639
Subcategory
III-3 Summary of Subcategory Processes and 640
Associated Waste Streams
IV-1 Production Normalizing Parameters 647
V-l Water Discharge Rates for Anode 659
and Cathode Paste Plant Wet
Air Pollution Control (1/kkg)
V-2 Primary Aluminum Sampling Data 660
Anode Paste Plant Wet Air
Pollution Control Raw Wastewater
V-3 Water Discharge Rates for Anode 662
Bake Plant Wet Air Pollution
Control (1/kkg of Anodes Baked)
V-4 Primary Aluminum Sampling Data 663
Anode Bake Plant Scrubber
Liquor Raw Wastewater
V-5 Water Discharge Rates for Anode 665
Contact Cooling and Briquette
Quenching (1/kkg of Green
Anodes or Briquettes Manufactured)
V-6 Primary Aluminum Sampling Data 666
Paste Plant Contact Cooling
Water Raw Wastewater
V-7 Water Discharge Rates for 668
Cathode Reprocessing
(1/kkg of Cryolite Production)
V-8 Primary Aluminum Sampling Data 669
Cathode Reprocessing Raw Wastewater
V-9 Water Discharge Rates for 784
Potline Wet Air Pollution
Control (1/kkg of Aluminum
Reduction Production)
597
-------
PRIMARY ALUMINUM SUBCATEGORY
LIST OF TABLES (Continued)
Table Title Page
V-10 Primary Aluminum Sampling Data 675
Potline Wet Air Pollution
Control Raw Wastewater
V-ll Water Discharge Rates for 679
Potline S02 Wet Air
Pollution Control (1/kkg of
Aluminum Reduced)
V-12 Water Discharge Rates for 680
Potroom Wet Air Pollution
Control (1/kkg of Aluminum
Reduction Production)
V-13 Primary Aluminum Sampling Data 681
Potroom Wet Air Pollution
Control Raw Wastewater
V-14 Water Discharge Rates for 686
Degassing Wet Air Pollution
Control (1/kkg of Aluminum
Refined and Degassed)
V-15 Primary Aluminum Sampling Data 687
Refining and Degassing Wet
Air Pollution Control Raw
Wastewater
V-16 Water Discharge Rates for Pot 688
Repair-Pot Soaking (1/kkg of
Aluminum Reduction Production)
V-17 Water Discharge Rates for Direct 689
Chill Casting Contact Cooling
(Primary Aluminum Subcategory)
(1/kkg of Aluminum Cast)
V-18 Water Discharge Rates for Direct 690
Chill Casting Contact Cooling
(Aluminum Forming Category)
V-19 Water Discharge Rates for 692
Continuous Rod Casting
Contact Cooling
(1/kkg of Aluminum Cast)
V-20 Primary Aluminum Sampling Data 693
Casting Contact Cooling
Water Raw Wastewater
598
-------
PRIMARY ALUMINUM SUBCATEGORY
LIST OF TABLES (Continued)
Table Title Page
V-21 Primary Aluminum Sampling Data 695
Miscellaneous Wastewater
V-22 Primary Aluminum Sampling Data 701
Treatment Plant Samples -
Plant A
V-23 Primary Aluminum Sampling Data 702
Treatment Plant Samples -
Plant B
V-24 Primary Aluminum Sampling Data 704
Treatment Plant Samples -
Plant C
V-25 Primary Aluminum Sampling Data 706
Treatment Plant Samples -
Plant D
V-26 Primary Aluminum Sampling Data 708
Treatment Plant Samples -
Plant E
V-27 Primary Aluminum Sampling Data 710
Treatment Plant Samples -
Plant F
V-28 Reported Presence or Absence of 712
Toxic Pollutants
V-29 Source Water Characteristics 713
V-30 Raw Wastewater Characteristics - 714
Potline Scrubber Blowdown
V-31 Concentration of PAH in Potline 715
Raw Wastewater
V-32 Sample Data Summary for PAH 716
Analysis in Potline Scrubber Liquor
- Clarifier Effluent, Filter Effluent,
and Carbon Adsorption Effluent
V-33 Sample Data Summary for Metal 717
Removal in Potline Scrubber Liquor
- Clarifier and Filter Effluent
VI-1 Frequency of Occurrence of 735
Toxic Pollutants Primary
Aluminum Raw Wastewater
599
-------
PRIMARY ALUMINUM SUBCATEGORY
LIST OF TABLES (Continued)
Table Title Page
VI-2 Toxic Pollutants Never Detected 739
VI-3 Toxic Pollutants Never Found Above Their 741
Analytical Ouantification Level
VI-4 Toxic Pollutants Detected in a Small 742
Number of Sources
VIII-1 Cost of Compliance for the 757
Primary Aluminum Subcategory
Direct Dischargers (March
1982 - Millions of Dollars)
X-l Current Recycle Practices 782
Within the Primary
Aluminum Subcategory
X-2 Pollutant Removal Estimates 783
for Primary Aluminum Direct
Dischargers Toxic Organics
X-3 Pollutant Removal Estimates for 784
Primary Aluminum Direct
Dischargers Inorganics -
Combined Metals Data Base
(CMDB)
X-4 Pollutant Removal Estimates for 785
Primary Aluminum Direct
Dischargers Inorganics -
Alternate Data Base
X-5 Pollutant Removal Estimates for 786
Primary Aluminum Inorganics -
Total
X-6 BAT Wastewater Discharge Rates 787
for the Primary Aluminum
Subcategory
X-7 BAT Effluent Limitations for 789
the Primary Aluminum
Subcategory
XI-1 Plants Currently Manufacturing 818
or Capable of Manufacturing
High Purity Alloys Using
Alternate In-Line Fluxing
and Filtering
600
-------
PRIMARY ALUMINUM SUBCATEGORY
LIST OF TABLES (Continued)
Table Title Page
XI-2 NSPS Wastewater Discharge Rates 819
for the Primary Aluminum
Subcategory
XI-3 NSPS for the Primary Aluminum 821
Subcategory
XII-1 PSNS Wastewater Discharge Rates 839
for the Primary Aluminum
Subcategory
XII-2 PSNS for the Primary Aluminum 841
Subcategory
601
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PRIMARY ALUMINUM SUBCATEGORY
LIST OF FIGURES
Figure
III-l
111 -2
V-l
V-2
V-3
V-4
V-5
V-6
X-l
X-2
X-3
X-4
Title
Primary Aluminum Reduction Process
Geographic Locations of Primary Aluminum
Reduction Plants
Page
Sampl
Sampling Sites at Primary Aluminum Plant B
Sampl
Sampl
ng Sites at Primary Aluminum Plant A
ng Sites at Primary Aluminum Plant C
ng Sites at Primary Aluminum Plant D
Sampling Sites at Primary Aluminum Plant E
Sampling Sites at Primary Aluminum Plant F
BAT Treatment Scheme Option A
Primary Aluminum Subcategory
BAT Treatment Scheme Option B
Primary Aluminum Subcategory
BAT Treatment Scheme Option C
Primary Aluminum Subcategory
BAT Treatment Scheme Option E
Primary Aluminum Subcategory
641
642
718
719
720
721
722
723
808
809
810
811
602
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - I
SECTION I
SUMMARY AND CONCLUSIONS
On April 8, 1974, EPA promulgated technology-based effluent
limitations guidelines and performance standards for the primary
aluminum smelting subcategory of the Nonferrous Metals Manufac-
turing Point Source Category. This regulation included BPT, BAT,
NSPS, and PSNS limitations. EPA promulgated amendments to BAT,
NSPS, and PSNS for this subcategory pursuant to the provisions of
the Clean Water Act Amendments of 1977. This supplement provides
a compilation and analysis of the background material used to
develop these amended effluent limitations and standards.
On March 8, 1984 (49FR8742) EPA promulgated final amendments to
40 CFR Part 421, substantially revising BAT limitations and new
source and pretreatment standards for both primary and secondary
aluminum smelting. After promulgation of these amendments, the
Aluminum Association, Kaiser Aluminum and Chemical Corp.,
Reynolds Metals Company, the Aluminum Recycling Association, and
others filed petitions to review the regulation. In November 1985
these four parties entered into two settlement agreements which
resolved issues raised by the petitioners related to the primary
aluminum and secondary aluminum subcategories. In accordance
with these Settlement Agreements, EPA published a notice of
proposed rulemaking on May 20, 1986 and solicited comments.
EPA then promulgated final amendments to the regulation for the
Primary Aluminum Subcategory on July 7, 1987 (52 FR 25552)
concerning four topics, which are summarized here.
The BAT limitations for benzo(a)pyrene were amended in two
respects: first, to incorporate variability factors into the
daily maximum and monthly average limitations; and second, to
only provide discharge allowances for benzo(a)pyrene to those
processes which generate this substance. Further, clarification
is provided on 2 items related to regulation of benzo(a)pyrene.
The BAT limitations and NSPS and PSNS for fluoride are amended to
be based upon the pooled variability factors calculated from data
for seven metal pollutants in the combined metals data base,
namely 4.10 and 1.82 for the daily and monthly variability
factors, respectively. This amendment was made because of
petitioners concerns about the presence of complex fluoride ions
and aluminum salts in the wastewater.
3rief guidance is provided on the treatment values that permit
writers may provide fcr spent potliner leachate, even though EPA
considers spent potliner leachate to be a non-process and
therefore a non-scope flow.
The NSPS pH standards for direct chill casting contact cooling
water are amended to a range of 6.0 to 10.0 standard units at all
603
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PRIMARY ALUMINUM SUBCATEGORY SECT - I
t imes.
The primary aluminum subcategory is comprised of 31 plants. Of
the 31 plants, 24 discharge directly to rivers, lakes, or
streams; none discharge to publicly owned treatment works (POTW);
and seven achieve zero discharge of process wastewater.
EPA first examined the primary aluminum subcategory to determine
whether differences in raw materials, final products, manufactur-
ing processes, equipment, age and size of plants, and water usage
required the development of separate effluent limitations and
standards for different segments of the subcategory. This
involved a detailed analysis of wastewater discharge and treated
effluent characteristics, including (1) the sources and volume of
water used, the processes employed, and the sources of pollutants
and wastewaters in the plant; and (2) the constituents of waste-
waters, including toxic pollutants.
Several distinct control and treatment technologies (both in-
plant and end-of-pipe) applicable to the primary aluminum
subcategory were identified. The Agency analyzed both histori-
cal and newly generated data on the performance of these technol-
ogies, including their nonwater quality environmental impacts
(air quality impacts and solid waste generation) and energy
requirements. EPA also studied various flow reduction techniques
reported in the data collection portfolios (dcp) and plant
visits.
Engineering costs were prepared for each of the control and
treatment options considered for the subcategory. These costs
were then used by the Agency to estimate the impact of implement-
ing the various options on the industry. For each control and
treatment option that the Agency found to be most effective and
technically feasible in controlling the discharge of pollutants,
the number of potential closures, number of employees affected,
and impact on price were estimated. These results are reported
in a separate document entitled "The Economic Impact Analysis of
Effluent Limitations and Guidelines and Standards for the
Nonferrous Smelting and Refining Industry".
Based on consideration of the above factors, EPA identified vari-
ous control and treatment technologies which formed the basis for
BAT and selected control and treatment appropriate for each set
of standards and limitations. The mass limitations and standards
for BAT, NSPS, and PSNS are presented in Section II.
For BAT, the Agency has built upon the BPT basis of lime precipi-
tation and sedimentation by adding in-process control technolo-
gies which include recycle of process water from air pollution
control and metal contact cooling waste streams. Filtration is
added as an effluent polishing step to further reduce metals,
toxic organics, and suspended solids concentrations. In addi-
tion, cyanide precipitation is added to control cyanide. To meet
the BAT effluent limitations based on this technology, the
primary aluminum smelting subcategory is estimated to incur a
604
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PRIMARY ALUMINUM SUBCATEGORY SECT - I
capital cost of $10.5 million (March, 1982 dollars) and an annual
cost of $16 million (March, 1982 dollars).
The best demonstrated technology (BDT), which is the technical
basis of NSPS, is equivalent to BAT for most waste streams. In
selecting BDT, EPA recognizes that new plants have the opportu-
nity to implement the best and most efficient manufacturing pro-
cesses and treatment technology. As such, the technology basis
of NSPS for the removal of toxic organics present in scrubber
wastewater from anode paste plants, anode bake plants, and pot
lines, is dry alumina air pollution scrubbing systems. Potroom
scrubbing is eliminated based on efficient capture of emissions
with potline scrubbers. Degassing wet air pollution control is
eliminated through in-line fluxing and filtering. Treatment of
toxic metals and toxic organics is based upon lime precipitation,
sedimentation, and filtration. Cyanide precipitation is the
basis for the control of cyanide, and oil skimming is included
for the control of oil and grease.
The Agency is not promulgating pretreatment standards for exist-
ing sources (PSES) since there are no indirect discharging plants
in the primary aluminum subcategory. The technology basis for
pretreatment standards for new sources (PSNS) is the best demon-
strated technology, and the PSNS are identical to NSPS for all
building blocks.
605
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - II
SECTION II
RECOMMENDATIONS
EPA has divided the primary aluminum subcategory into 12
subdivisions or building blocks for the purpose of effluent
limitations and standards. These building blocks are:
(a) Anode and cathode paste plant wet air pollution control
(b) Anode bake plant wet air pollution control
(c) Cathode reprocessing
(d) Anode and briquette contact cooling
(e) Potline wet air pollution control
(f) Potline S02 wet air pollution control
(g) Potroom wet air pollution control
(h) Degassing wet air pollution control
(i) Pot repair and pot soaking
(j) Direct chill casting contact cooling
(k) Continuous rod casting contact cooling
(1) Stationary and shot casting contact cooling
EPA promulgated BPT, BAT, NSPS, and PSNS effluent limitations for
the primary aluminum subcategory on April 8, 1974 as Subpart B of
40 CFR Part 421. Unlike this rulemaking, the limitations and
standards were developed for the entire aluminum smelting
process, not on the basis of individual building blocks. BPT was
promulgated based on effluent concentrations achievable by the
application of chemical precipitation and sedimentation (lime and
settle) technology and average process wastewater flowrates. For
this rulemaking, EPA is not modifying these BPT limitations.
The following BPT effluent limitations were promulgated:
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
EPA is modifying the BAT effluent limitations to take into
account pollutant concentrations achievable by the application of
chemical precipitation, sedimentation, and multimedia filtration
(lime, settle, and filter) technology and in-process flow
reduction control methods, along with preliminary treatment
consisting of cyanide precipitation with ferrous sulfate for
Metric Units - kg/kkg of product
English Units - lbs/1,000 lbs of product
Fluor ide
Total Suspended Solids
PH
Within the range of 6 to 9
at all times
2.0
3.0
1 . 0
1 . 5
607
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - II
selected waste streams. The following BAT effluent limitations
are promulgated for existing sources:
(a) Anode and Cathode Paste Plant Wet Air Pollution Control BAT
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of paste produced
English Units - lbs/million lbs of paste produced
Benzo(a)pyrene 0.005 0.002
Antimony 0.263 0.117
Nickel 0.075 0.050
Aluminum 0.831 0.369
Fluoride 8.092 3.591
(b) Anode Contact Cooling and Briquette Quenching BAT
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of anodes cast
English Units - lbs/million lbs of anodes cast
Benzo(a)pyrene 0.007 0.003
Antimony 0.403 0.180
Nickel 0.115 0.077
Aluminum 1.277 0.566
Fluoride 12.440 5.518
(c) Anode Bake Plant Wet Air Pollution Control (Closed top
ring fumace) BAT
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units — mg/kg of anodes baked
English Units - lbs/million lbs of anodes baked
Benzo(a)pyrene 0.146 0.067
Antimony 8.346 3.719
Nickel 2.378 1.600
Aluminum 26.420 11.720
Fluoride 257.300 114.200
608
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - II
(d) Anode Bake Plant Wet Air Pollution Control (Open top
ring furnace with spray tower only) BAT
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of anodes baked
English Units - lbs/million lbs of anodes baked
Benzo(a)pyrene
0.002
0.001
Antimony
0.097
0.043
Nickel
0.028
0.019
Aluminum
0. 306
0.136
Fluor ide
2.975
1. 320
(e) Anode Bake Plant Wet Air Pollution Control (Open top ring
furnace with wet electrostatic precipitator and spray
tower) BAT
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units -
mg/kg of anodes
baked
English Units - lbs/million lbs of anodes baked
3enzo(a)pyrene
0.025
0.011
Ant imony
1.409
0.628
Nickel
0.402
0 . 270
Aluminum
4.461
1.979
Fluor ide
43.440
19.270
(f) Anode Bake Plant Wet Air
Pollution Control (Tunnel kiln) BAT
Pollutant or
Maximum for
Maximum for
Pollutant Property
Any One Day
Monthly Average
Metric Units - mg/kg of anodes baked
English Units - lbs/million lbs of anodes baked
Benzo(a)pyrene
0.038
0.018
Ant imony
2.197
0.979
Nickel
0.626
0.421
Alumi num
6.953
3.084
Fluor ide
67.710
30.050
609
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - II
(g) Cathode Reprocessing (Operated with dry potline scrubbing
and not commingled with other process or nonprocess
wa t e r s ) BAT
Pollutant or
Pollutant Property
Maximum for
Any One Day
Maximum for
Monthly Average
Metric Units - mg/kg of cryolite recovered
English Units - lbs/million lbs of cryolite recovered
Ben2o(a)pyrene 1.181 0.547
Antimony 420.400 189.200
Cyanide 157.600 70.060
Nickel 80.570 35.030
Aluminum 273.200 122.600
Fluoride 29,430.000 13,310.000
(h) Cathode Reprocessing (Operated with dry potline scrubbing
and commingled withother process or nonprocess waters) BAT
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of cryolite recovered
English Units - lbs/million lbs of cryolite recovered
Benzo(a)pyrene 1.181 0.547
Antimony 67.610 30.120
Cyanide 157.600 70.060
Nickel 19.270 12.960
Aluminum 214.000 94.930
Fluoride 2,084.000 924.800
(i) Cathode Reprocessing (Operated with wet potline scrubbing) BAT
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of cryolite recovered
English Units - lbs/million lbs of cryolite recovered
Benzo(a)pyrene
0.000
0 .000
Antimony
0 . 000
0.000
Cyanide
0 . 000
0 . 000
Nickel
0 . 000
0 .000
Aluminum
0.000
0 . 000
Fluor ide
0.000
0 . 000
610
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - II
(j) Potline Wet Air Pollution Control (Operated without cathode
reprocessing) BAT
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum produced from electrolytic
reduction
English Units - lbs/million lbs of aluminum produced from
electrolytic reduction
Benzo(a)pyrene 0.028 0.013
Antimony 1.618 0.721
Nickel 0.461 0.310
Aluminum 5.120 2.271
Fluoride 49.860 22.130
(k) Potline Wet Air Pollution Control (Operated with cathode
reprocessing and not commingled with other process or
nonprocess waters) BAT
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum produced from electrolytic
reduction
English Units - lbs/million lbs of aluminum produced from
electrolytic reduction
Benzo(a)pyrene 0.028 0.013
Antimony 10.060 4.525
Cyanide 3.771 1.676
Nickel 1.928 0.838
Aluminum 6.537 2.993
Fluoride 703.900 318.500
611
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - II
(1) Potline Wet Air Pollution Control (Operated with cathode
reprocessing and commingled with other orocess or nor.process
wastewaters) BAT *
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric units - mg/kg of aluminum produced from electrolytic
reduction
English Units - lbs/million lbs of aluminum produced from
electrolytic reduction
Benzo(a)pyrene 0.028 0.013
Antimony 1.618 0.721
Cyanide 3.771 1.676
Nickel 0.461 0.310
Aluminum 5.120 2.271
Fluoride 49.860 22.130
(m) Pot room Wet Ai r Pollution Control BAT
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum produced from electrolytic
reduction
English Units - lbs/million lbs of aluminum produced from
electrolytic reduction
Benzo(a)pyrene 0.056 0.026
Antimony 3.204 1.428
Nickel 0.913 0.614
Aluminum 10.140 4.499
Fluoride 98.770 43.830
(n) Potline SO? Emissions Wet Air Pollution Control BAT
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum produced from electrolytic
reduct ion
English Units - lbs/million lbs of aluminum produced from
electrolytic reduction
Benzo(a)pyrene 0.045 0.021
Antimony 2.588 1.153
Cyanide 0.738 0.496
Nickel 8.194 3.634
Aluminum 79.790 35.400
Fluor ide
612
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - II
(0) Degassing Wet Air Pollution Control BAT
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum produced from electrolytic
reduction
English Units - lbs/million lbs of aluminum produced from
electrolytic reduction
Benzo(a)pyrene (1) (1)
Antimony 5.036 2.244
Nickel 1.435 0.965
Aluminum 15.940 7.071
Fluoride 155.300 68.880
(1) There shall be no discharge allowance for this pollutant
(p) Pot Repair and Pot Soaking BAT
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum produced from electrolytic
reduction
English Units - lbs/million lbs of aluminum produced from
electrolytic reduction
Benzo(a)pyrene 0.000 0.000
Antimony 0.000 0.000
Nickel 0.000 0.000
Aluminum 0.000 0.000
Fluoride 0.000 0.000
613
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - II
(q) Direct Chi 11 Casting Contact Coolinq BAT
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - rag/kg of aluminum product from direct chill
casting
English Units - lbs/million lbs of aluminum product from
direct chill casting
Benzo(a)pyrene (1) (1)
Antimony 2.565 1.143
Nickel 0.731 0.492
Aluminum 8.120 3.602
Fluoride 79.080 35.090
(r) Continuous Rod Casting Contact Cooling BAT
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum product from rod casting
English Units - lbs/million lbs of aluminum product from rod
casting
Benzo(a)pyrene (1) (1)
Antimony 0.201 0.089
Nickel 0.057 0.038
Aluminum 0.636 0.282
Fluoride 6.188 2.746
(1) There shall be no discharge allowance for this pollutant
614
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - II
(s) Stationary Casting or Shot Casting Contact Cooling BAT
Pollutant or
Pollutant Property
Maximum for Maximum for
Any One Day Monthly Average
Metric Units - mg/kg of aluminum product from stationary casting
or shot casting
English Units - lbs/million lbs of aluminum product from
stationary casting or shot casting
EPA is modifying NSPS based on the effluent concentrations
achievable by the application of chemical precipitation,
sedimentation, and multimedia filtration (lime, settle, and
filter) technology and elimination of pollutant discharges from
air pollution control through the use of dry scrubbing, along
with preliminary treatment consisting of oil skimming and cyanide
precipitation with ferrous sulfate for selected waste streams.
The following effluent standards are promulgated for new sources:
(a) Anode and Cathode Paste Plant Wet Air Pollution Control NSPS
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Antimony
Nickel
Aluminum
Fluoride
Benzo(a)pyrene
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
Metric Units - mg/kg of paste produced
English Units - lbs/million lbs of paste produced
Benzo(a)pyrene
Antimony
Nickel
Aluminum
Fluor ide
Oil and Grease
TSS
0 .000
0 .000
0 . 000
0 . 000
0 .000
0.000
0 .000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
PH
Within the range of 7.0 to 10.0
at all times
615
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - II
(b) Anode Contact Cooling and Briquette Quenching NSPS
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of anodes cast
English Units - lbs/million lbs of anodes cast
Benzo(a)pyrene
0.007 0.003
Ant imony
0.403 0.180
Nickel
0.115 0.077
Aluminum
1.277 0.566
Fluor ide
12.440 5.518
Oil and Grease
2.090 2.090
TSS
3.135 2.508
P«
Within the range of 7.0 to 10.0
at all times
(c) Anode Bake Plant
Wet Air Pollution Control NSPS
Pollutant or
Maximum for Maximum for
Pollutant Property
Any One Day Monthly Average
Metric Units - mg/kg of anodes baked
English Units - lbs/million lbs of anodes baked
Benzo(a)pyrene
0 . 000
0 . 000
Ant imony
0 . 000
0 . 000
Nickel
0.000
0.000
Aluminum
0.000
0.000
Fluor ide
0.000
0.000
Oil and Grease
0.000
0.000
TSS
0.000
0.000
pH Within the range of 7.0 to 10.0
at all times
616
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - II
(d) Cathode Reprocessing NSPS (Operated with dry potline scrubbing
and not commingled with other process or nonprocess waters)
Pollutant or
Pollutant Property
Maximum for
Any One Day
Maximum for
Monthly Average
Metric Units - mg/kg of cryolite recovered
English Units - lbs/million lbs of cryolite recovered
Benzo(a)pyrene
Ant imony
Cyanide
Nickel
Aluminum
Fluor ide
Oil and Grease
TSS
pH
1
420
157
80
273
430
350
2,172
Within
29
.181 0.547
.400 189.200
.600 70.060
.570 35.030
.200 122.600
.000 13,310.000
.300 350.300
.000 945.800
the range of 7.0 to 10
at all times
(e) Cathode Reprocessing NSPS (Operated with dry potline scrubbing
and commingled with other process or nonprocess waters)
Pollutant or
Pollutant Property
Maximum for
Any One Day
Maximum for
Monthly Average
Metric Units - mg/kg of cryolite recovered
English Units - lbs/million lbs of cryolite recovered
Benzo(a)pyrene
Ant imony
Cyanide
Nickel
Aluminum
Fluoride
Oil and Grease
TSS
PH
1.181
67.610
157.600
19.270
214.000
2,084.000
350.300
2,172.000
0. 547
30.130
70 .060
12.960
94.930
924.800
350.300
945.800
Within the range of 7.0 to 10
at all times
617
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - II
(f) Potline Wet Air Pollution Control NSPS
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum produced from electrolytic
reduction
English Units - lbs/million lbs of aluminum produced from
electrolytic reduction
Benzo(a)pyrene
0.000
0.000
Antimony
0.000
0.000
Nickel
0.000
0.000
Aluminum
0.000
0.000
Fluoride
0.000
0 .000
Oil and Grease
0.000
0 .000
TSS
0. 000
0.000
pH Within the range of 7.0 to 10.0
at all times
(g) Potroom Wet Air Pollution Control NSPS
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum produced from electrolytic
reduction
English Units - lbs/million lbs of aluminum produced from
electrolytic reduction
Benzo(a)pyrene 0.000 0.000
Antimony 0.000 0.000
Cyanide 0.000 0.000
Nickel 0.000 0.000
Aluminum 0.000 0.000
Fluoride 0.000 0.000
Oil and Grease 0.000 0.000
TSS 0.000 0.000
pH Within the range of 7.0 to 10.(
at all times
618
-------
PRIMARY ALUMINUM SUBCATEGORY
SECT
II
(^) Potline SO? Emissions Wet Air Pollution Control NSPS
Pollutant or
Pollutant Property
Maximum for
Any One Day
Maximum for
Monthly Average
Metric Units - mg/kg of aluminum produced from electrolytic
reduction
English Units - lbs/million lbs of aluminum produced from
electrolytic reduction
Benzo(a)pyrene
Antimony
Nickel
Aluminum
Fluoride
Oil and Grease
Total Suspended Solids
PH
0.045 0.021
2.588 1.153
0.738 0.496
8.194 3.634
79.790 35.400
13.410 13.410
20.120 16.090
Within the range of 7.0 to 10,
at all times
(i) Degassing Wet Air Pollution Control NSPS
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum produced from electrolytic
reduction
English Units - lbs/million lbs of aluminum produced from
electrolytic reduction
Benzo(a)pyrene
0.000 0.000
Antimony
0.000 0.000
Nickel
0.000 0.000
Aluminum
0.000 0.000
Fluoride
0.000 0.000
Oil and Grease
0.000 0.000
TSS
0.000 0.000
PH
Within the range of 7.0 to
at all times
619
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - II
(j) Pot Repair and Pot Soaking NSPS
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units -
mg/kg of aluminum produced from electrolytic
refining
English Units
- lbs/million lbs of aluminum
produced from
electrolytic reduction
Benzo(a)pyrene
0.000
0.000
Ant imony
0 .000
0.000
Nickel
0.000
0.000
Aluminum
0.000
0 . 000
Fluoride
0.000
0.000
Oil and Grease
0 .000
0 . 000
TSS
0.000
0.000
pH
Within the range of 7.0 to 10.0
at all times
(k) Direct Chill
Casting Contact Cooling NSPS
Pollutant or
Maximum for
Maximum for
Pollutant Property
Any One Day
Monthly Average
Metric Units -
mg/kg of aluminum product from
direct chill
casting
English Units
- lbs/million lbs of aluminum
product from
direct chill casting
Benzo(a)pyrene
(1)
(1)
Ant imony
2.565
1.143
Nickel
0.731
0.492
Aluminum
8.120
3.602
Fluoride
79.080
35.090
Oil and Grease
13.290
13.290
TSS
19.940
15.950
pH
(2)
(2)
(1) There shall be no discharge allowance for this pollutant.
(2) The pH shall be maintained within the range of 7.0 to 10.0
at all times except for those situations when this waste is
discharged separately and without commingling with any other
wastewater in which case the pH shall be within the range of 6.0
to 10.0 at all times.
620
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - II
(1) Continuous Rod Casting Contact Cooling NSPS
Pollutant or
Pollutant Property
Maximum for Maximum for
Any One Day Monthly Average
Metric Units - mg/kg of aluminum product from rod casting
English Units - lbs/million lbs of aluminum product from
rod casting
Benzo(a)pyrene
Ant imony
Nickel
Aluminum
Fluor ide
Oil and Grease
TSS
(1)
0.201
0.057
0.636
6.188
1.040
1 . 560
(1)
0.089
0.038
0. 282
2.746
1.040
1.248
pH
Within the range of 7.0 to 10.0
at all times
(m) Stationary Casting or Shot Casting Contact Cooling NSPS
Metric Units - mg/kg of aluminum product from stationary casting
or shot casting
English Units - lbs/million lbs of aluminum product from
stationary casting or shot casting
EPA is not promulgating pretreatment standards for existing
sources (PSES) for the primary aluminum subcategory since there
are no existing indirect dischargers.
EPA is modifying PSNS based on the effluent concentrations
achievable by the application of chemical precipitation,
sedimentation, and multimedia filtration (lime, settle, and
Pollutant or
Pollutant Property
Maximum for Maximum for
Any One Day Monthly Average
Benzo(a)pyrene
Antimony
Nickel
Alumi num
Fluor ide
Oil and Grease
TSS
pH
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
Within the range of 7.0 to 10.0
at all times
621
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - II
filter) technology and elimination of pollutant discharges
through the use of dry scrubbing, along with preliminary
treatment consisting of cyanide precipitation with ferrous
sulfate for selected waste streams. The following pretreatment
standards are promulgated for new sources:
(a) Anode and Cathode Paste Plant Wet Air Pollution Control PSNS
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of paste produced
English Units - lbs/million lbs of paste produced
Benzo(a)pyrene
Nickel
Fluoride
0.000
0.000
0.000
0.000
0.000
0.000
(b) Anode Contact Cooling and Briquette Quenching PSNS
Pollutant or
Pollutant Property
Maximum for Maximum for
Any One Day Monthly Average
Metric Units - mg/kg of anodes cast
English Units - lbs/million lbs of anodes cast
Benzo(a)pyrene
Nickel
Fluoride
0.007
0.115
12.440
0.003
0.077
5.518
(c) Anode Bake Plant Wet Air Pollution Control PSNS
Pollutant or
Pollutant Property
Maximum for Maximum for
Any One Day Monthly Average
Metric Units - mg/kg of anodes baked
English Units - lbs/million lbs of anodes baked
Benzo{a)pyrene
Nickel
Fluoride
0.000
0 .000
0 .000
0.000
0.000
0.000
622
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - II
(d) Cathode Reprocessing PSNS (Operated with dry potline scrubbing
and not commingled with other process or nonprocess waters)
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of cryolite recovered
English Units - lbs/million lbs of cryolite recovered
Benzo(a)pyrene 1.181 0.547
Cyanide 157.600 , 70.060
Nickel 80.570 35.030
Fluoride 29,430.000 13,310.000
(e) Cathode Reprocessing PSNS (Operated with dry potline
scrubbing and commingled with other process or nonprocess
waters)
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of cryolite recovered
English Units - lbs/million lbs of cryolite recovered
Benzo(a)pyrene 1.181 0.547
Cyanide 157.600 70.060
Nickel 19.270 12.960
Fluoride 2,084.000 924.800
(f) Potline Wet Ai r Pollution Control PSNS
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum produced from electrolytic
reduction
English Units - lbs/million lbs of aluminum produced from
electrolytic reduction
Benzo(a)pyrene 0.000 0.000
Nickel 0.000 0.000
Fluoride 0.000 0.000
623
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - II
(g) Pot room Wet Ai r Pollution Control PSNS
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum produced from electrolytic
reduct ion
English Units - lbs/million lbs of aluminum produced from
electrolytic reduction
Benzo(a)pyrene 0.000 0.000
Nickel 0.000 0.000
Fluoride 0.000 0.000
(h) Potline S02 Emissions Wet Air Pollution Control PSNS
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum produced from electrolytic
reduction
English Units - lbs/million lbs of aluminum produced from
electrolytic reduction
Benzo(a)pyrene 0.045 0.021
Nickel 0.738 0.496
Fluoride 79.790 35.400
(i) Degassing Wet Air Pollution Control PSNS
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum produced from electrolytic
reduct ion
English Units - lbs/million lbs of aluminum produced from
electrolytic reduction
Benzo(a)pyrene 0.000 0.000
Nickel 0.000 0.000
Fluoride 0.000 0.000
624
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - II
(j) Pot Repair and Pot Soakinq PSNS
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum produced from electrolytic
reduction
English Units - lbs/million lbs of aluminum produced from
electrolytic reduction
Benzo(a)pyrene . 0.000 0.000
Nickel 0.000 0.000
Fluoride 0.000 0.000
(k) Direct Chi 11 Casting Contact Cooling PSNS
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum product from direct chill
casting
English Units - lbs/million lbs of aluminum product from
direct chill casting
Benzo( a )pyrene (.1) (1)
Nickel 0.731 0.492
Fluoride 79.080 35.090
(1) Continuous Rod Casting Contact Cooling PSNS
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum product from rod casting
English Units - lbs/million lbs of aluminum product from
rod casting
Benzo(a)pyrene (1) (1)
Nickel 0.057 0.038
Fluoride 6.188 2.746
625
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - II
(m) Stationary Casting or Shot Casting Contact Cooling PSNS
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kkg of aluminum product from stationary casting
or shot casting
English Units - lbs/billion lbs of aluminum product from
stationary casting or shot casting
Benzo(a)pyrene
Nickel
Fluoride
0.000
0.000
0.000
0.000
0.000
0.000
626
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - III
SECTION III
INDUSTRY PROFILE
This section of the Primary Aluminum Supplement describes the raw
materials and processes used in reducing alumina to aluminum and
presents a profile of the primary aluminum plants identified in
this study.
DESCRIPTION OF PRIMARY ALUMINUM PRODUCTION
All primary aluminum produced in the United States is
manufactured by the electrolytic reduction of alumina via the
Hall-Heroult Process. Figure III-l (page 641) is a block flow
diagram depicting the various process steps involved in the
manufacture of primary aluminum. The discussion that follows
provides a summary of the processes used in the smelting of
aluminum, with particular emphasis on where water is used.
RAW MATERIALS
The principal raw materials used in primary aluminum reduction
are alumina, metallurgical or petroleum coke, pitch, cryolite,
and aluminum fluoride. Alumina is the product of bauxite
refining.
ELECTROLYTIC ALUMINUM PRODUCTION
The manufacture of aluminum using the Hall-Heroult Process is
discussed in the following sections.
Reduction Cells
The electrolytic cells used in the Hall-Heroult Process are
called pots. These pots, ranging in size from 1.8 x 5.5 to 4.3 x
12.8 meters (6 x 18 to 14 x 42 feet), are made of cast iron and
lined with carbon. This carbon lining serves as the cathode in
the electrolytic circuit, collecting aluminum ions from the
electrolyte. In the primary aluminum industry, large numbers of
these pots (from 100 to 250 cells) are hooked electrically in
series. This forms the potline, the basic production unit of the
reduction plant. Potline? are generally contained in one or two
long, ventilated buildincs called potrooms.
The electrolyte is a solution of alumina in molten cryolite, a
double fluoride salt of calcium and aluminum. Alumina is
periodically added to and dissolved in the molten electrolyte to
maintain the alumina concentration. The cells are heated to
about 950°C, and an electrical current is passed through the
molten cryolite to force the aluminum ions to migrate to the
627
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - III
cathode, where they are reduced to aluminum. The molten
aluminum/ because of its heavier weight, collects in the bottom
of the pot, forming a layer beneath the cryolite-alumina
solution.
The anode is the electrical counterpart of the cathode in the
electrolytic cell. The anode used in the primary aluminum
industry is made from coal tar pitch and coke and when
electrically connected is given a positive charge. This positive
charge attracts negative ions from the cryolite solution,
transferring the positive charge to the aluminum. This is the
manner in which the positive aluminum ions, which are attracted
to the negatively charged cathode, are formed. Additionally, the
carbon anode reacts with by-product oxygen to form carbon
monoxide and carbon dioxide. Thus, the anode is consumed by the
process of charge transfer and must be replaced periodically.
Potline cells are generally operated with currents ranging from
80,000 to 100,000 amperes. Anodes used in the Hall-Heroult
Process are of two basic types: prebaked and Soderberg anodes.
Fabrication of prebaked and Soderberg anodes is performed in the
anode paste plant where coal tar pitch and ground petroleum coke
are blended together to form a paste. Prebaked anodes, as the
name suggests, are baked prior to their use in the electrolytic
cell. Iron rods are then attached to the anode so that it may be
suspended above the electrolytic cell. Above the electrolytic
cell, the anodes are assembled in two basic patterns. In the
side worked prebaked cell, the anodes are assembled in two rows
extending the length of the cell with the rows closely spaced in
the center of the cell. This arrangement provides a working area
on each side of the cell between the cell side lining and the
anodes where aluminum is added to the cell (thus the name side
worked prebake cell). In the center worked prebake cell, anodes
are placed in two rows and placed closer to the cell side lining,
providing the working area in the center of the cell between the
rows (thus the name center worked prebake cell). In 1984,
prebaked anodes were used in 20 of 31 primary aluminum plants.
The alternative to the prebaked anode is the Soderberg anode. In
the Soderberg process, the anode paste is used in the
electrolytic cell without prior processing. The paste is
periodically fed into a rectangular steel compartment above the
pot. The heat of the chemical reaction in the pot then bakes the
paste, fusing the new material with the old anode. The tip of
this anode projects through the steel shell into the electrolyte.
As the tip is oxidized, constant replacement of the anode is
possible. Two configurations exist in the aluminum industry using
the Soderberg process: (1) the Horizontal Stud Soderberg (HSS)
process and (2) the Vertical Stud Soderberg (VSS) process. The
HSS system uses horizontal studs or pins to support the anode
body, while the VSS system uses vertical pins. In the horizontal
Soderberg process, the holding pins are adjusted from the side of
the pot, while in the vertical Soderberg process the pins are
adjusted from the top. Since the paste is added from above,
complete hooding of the VSS cell is not possible, and more fumes
628
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - III
may be emitted to the potroom than with the use of prebaked anode
cells. The VSS and HSS cell configurations were originally
thought to have a great advantage since they eliminated the need
for a separate paste plant. The presence of carbon which has not
been solidified, however, has become a problem. The unbaked
carbon paste which is added to the anode gives off volatile
organic compounds (VOC). These VOC emissions may condense in the
ductwork or in the air pollution control equipment and cause
fouling. In addition, VOC and fluoride emissions must be
controlled simultaneously.
The prebaked anode is more expensive to manufacture because of
the bake plant requirement; however, it is the most electrically
efficient of the three anode types. The distribution of plants
in 1984 with VSS, HSS, and prebaked anodes is listed below:
It is essential for purity of the product aluminum and the
structural integrity of the cell that the molten aluminum be
isolated from the iron shell. If the pot was left unlined, the
iron would react with the electrolytic bath, and an iron-aluminum
alloy would be the result of the electrolysis. Therefore, a
carbon liner is used. A service life of up to three years may be
attained for a properly installed liner in a well-managed cell,
but an average life of between two and three years is reported to
be more common.
Upon failure of a liner, the cell is emptied, cooled, and removed
from the cell room to a working area. By mechanical drilling and
soaking in water, the shell is stripped of old lining material,
which may be processed through a cathode reprocessing facility
for recovery of fluoride values or simply set aside in a storage
yar d.
Potline cells emit gases containing particulates, fluoride
compounds, SOx, COx, tars, and oils. Emissions can be collected
by using hoods above the cells and treated by wet or dry
processes. Activated alumina adsorption is the most common dry
process; however, electrostatic precipitators are also used. Two
types of alumina are used in the electrolytic cell: floury and
sandy alumina. Sandy alumina is often used for air scrubbing
prior to its use as a raw material, while floury alumina is
generally not used as a scrubbing material because it lacks the
physical characteristics that make a good scrubbing material. The
alumina adsorption method allows for recycle of the fluoride back
to the cell. At the time of the 1974 rulemaking, wet pot line
air scrubbing was the largest single contributor of pollutants
(fluoride and TSS) to the plant's wastewater. At that time,
about 88 percent of the aluminum plants used wet scrubbing. In
Anode Type Number of Plants
Prebaked
VSS
HSS
20
4
7
629
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - III
contrast, only 35 percent of the plants are now using primary or
secondary wet scrubbing.
In many facilities (Vertical Stud Soderberg cells and side worked
prebaked cells), potline hooding does not provide adequate
control of emission from potline cells, and pollutants are
released into the potroom. In the VSS configuration of the
Soderberg process, paste addition and pin adjustment occur above
the cell and complete hooding is not possible. As a result,
facilities with the VSS configuration typically use potroom
scrubbing to control the release of pollutants from the cell.
Potroom air pollution control devices available are limited, by
cost, to wet scrubbers. The applicable dry systems, fluidized
bed alumina and injected alumina, have not been cost effective
because of the large volumes of air which must be treated. All
eight plants with secondary or potroom emission control in EPA's
data base use wet systems.
It is reported lithium carbonate may be added to the electrolytic
cells to reduce power consumptions and increase production. By
adding lithium to the electrolytic cell, physical properties of
the batch such as melting point, electrical conductivity, and the
density of the electrolyte are controlled. An added benefit, and
more relevant to this document, is that lithium reduces fluoride
emissions.
Dry potline scrubbing is reported to be detrimental to the
manufacture of certain high purity alloys. Normally 100 percent
of the potline feed has been used as scrubbing material; however,
using aluminum in this manner tends to concentrate impurities
such as iron and silicon in the electrolytic cell. This
precludes use of recycled alumina as a raw material to produce
these alloys. It is possible, however, to manufacture high
purity alloys in cells using dry scrubbers if only a relatively
small percentage (not greater than approximately 20 percent) of
the production capacity is dedicated to the manufacture of these
alloys. Fresh alumina is used to manufacture the alloys and the
alumina used for scrubbing is used as feed in other cells.
Wet scrubbers are also used to control sulfur emissions from the
potline. These scrubbers differ from those wet systems used to
control fluoride in that an alkali solution (normally sodium) is
used for scrubbing. Use of alkali scrubbers follows dry
scrubbing systems where particulate, fluoride, and organic air
pollutants are removed. In 1984, there were two known U.S.
plants operating sodium scrubbers on potline emissions to control
sulfur oxides.
Aluminum Fluxing and Deqassinq
The molten aluminum collected in the bottom of the electrolytic
pots is tapped and conveyed to holding furnaces for subsequent
refining and alloying. Refining consists of fluxing to remove
impurities and degassing to reduce entrapped hydrogen gas in the
molten aluminum. Oftentimes fluxing and degassing are performed
630
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PRIMARY ALUMINUM SUBCATEGORY SECT - III
in the holding furnace prior to casting. Degassing is performed
by injecting chlorine, nitrogen, argon, helium and mixtures of
chlorine and inert gases into the molten aluminum. Hydrogen
desorbs into the chlorine bubble due to the partial pressure
difference between the elements. The addition of a gas to the
melt also mixes the aluminum to assure that all materials added
concurrently for alloying are distributed evenly in the molten
aluminum.
Besides hydrogen, other impurities that affect product quality
are oxides of aluminum and magnesium, and trace elements such as
sodium, calcium, and lithium. Chlorine gas reacts with the trace
elements to form insoluble salt particles. These salt particles
and the metal oxide impurities rise to the surface of the molten
bath through specific gravity differences and flotation,
respectively. The impurities collected at the surface of the
molten metal, commonly referred to as dross, are skimmed and
removed from the furnace.
Solid fluxes, such as hexachloroethane, aluminum chloride, and
anhydrous magnesium chloride, may be used instead of gaseous
fluxing. These fluxes are added to the surface of the molten
metal and stirred in to obtain proper distribution and contact.
It is reported, however, solid fluxes are difficult to use and
generally less efficient than gaseous fluxes. Only one primary
aluminum facility reported using solid fluxes.
Two inherent problems with furnace fluxing and degassing are
corrosion and air pollution. Emissions from the furnace consist
of unreacted chlorine and aluminum chloride gas. Aluminum
chloride hydrolyzes in the stack and atmosphere to form acid mist
and aluminum oxide fumes. Fumes released by furnace degassing
and fluxing are treated by wet scrubbers at three plants.
There are two refining procedures currently available which, by
the nature of their operation, reduce chlorine fumes from
refining operations and thus the need for air pollution control
devices. Chlorine fumes are reduced through the use of alternate
in-line fluxing and filtering techniques and with the MRL-P28
process by containing the chlorine under a layer of molten salt
and the subsequent formation of magnesium chloride.
Alternate in-line fluxing and filtering is performed outside of
the holding furnace just prior to casting. There are three basic
in-line fluxing and filtering techniques: 1) flotation, 2)
impingement, and 3) counter flow impingement. Flotation in-line
fluxing is very similar to furnace degassing and fluxing methods.
A mixture of gases, including chlorine, is bubbled
countercurrently through the molten metal to remove impurities.
Gas is distributed to the molten metal with a rotating vane,
yielding better bubble distribution, and therefore better removal
efficiency and lower chlorine demands because a stoichiometric
amount of gas can be used. In this way, subsequent fuming is
reduced because less chlorine is required.
631
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - III
The second in-line fluxing technique listed, impingement, is
actually a filtering technique. A ceramic or fiberglass media is
used to filter the molten aluminum just prior to casting. In-
line filters are reported to remove metal oxides so that only
enough chlorine need be added to remove hydrogen and trace
metals. Once again, fuming problems are reduced because less
chlorine is required. Oftentimes this technology is used in
conjunction with furnace fluxing. Counter flow impingement in-
line fluxing is a combination of the first two methods. Gas is
distributed to the molten aluminum through the filter media and
then allowed to bubble up through the molten aluminum.
In the MRL-P28 method of degassing, 97 percent nitrogen and three
percent Freon 12 is used. A molten salt cover, consisting of
sodium chloride and potassium chloride or magnesium chloride and
potassium chloride is used to supress fuming. It is reported
this technology is technically equivalent to chlorine fluxing and
reduces stack emissions by a factor of 20 when compared to
chlorine.
Casting
Casting is the final step at most aluminum reduction plants. Pig
and sow casting, direct chill casting, continuous rod casting,
and shot casting are the most common methods of casting used in
the primary aluminum subcategory.
Vertical direct chill casting is characterized by continuous
solidification of the metal while it is being poured. The length
of an ingot or billet cast using this method is determined by the
vertical distance it is allowed to drop rather than by mold
dimensions. Molten aluminum is tapped from the smelting furnace
and flows through a distributor channel into a shallow mold.
Noncontact cooling water circulates within this mold, causing
solidification of the aluminum. The base of the mold is attached
to a hydraulic cylinder which is gradually lowered as pouring
continues. As the solidified aluminum leaves the mold, it is
sprayed with contact cooling water to reduce the temperature of
the forming ingot or billet. The cylinder continues to descend
into a tank of water, causing further cooling of aluminum as it
is immersed. When the cylinder has reached its lowest position,
pouring stops and the ingot is lifted from the pit. The
hydraulic cylinder is then raised and positioned for another
casting cycle.
Horizontal direct chill casting is performed in much the same way
as vertical direct chill casting. The primary difference is that
the cast aluminum is conveyed from the mold in the horizontal
direction rather than vertically. Twenty-six primary aluminum
plants reported using direct chill casting.
In continuous rod casting, a ring mold is fitted into the edge of
a rotating casting wheel. Molten aluminum is then poured into
the mold and cools as the mold assembly rotates. After the wheel
has rotated about 160 degrees, the pliable aluminum bar is
632
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - III
released. Immediately following release from casting the rod is
transported on conveyers to a rolling mill where the diameter of
the rod is reduced. Thus it can be seen continuous rod casting
is generally associated with aluminum forming. Three primary
aluminum plants reported using continuous rod casting to cast
molten aluminum extracted from the pots.
Stationary casting is used to cast pigs and sows. In this method
of casting, the molds are stationary and the contact cooling
water generally evaporates if it is used. Eight plants with
stationary casting were identified.
One plant reported pebble casting which appears to be similar to
shot casting. Generally, aluminum shot is used as a deoxidant in
the steel industry. Molten metal is poured into a vibrating
feeder, where droplets of molten metal are formed through
perforated openings. The droplets are cooled in a quench tank.
Water is generally recycled, and periodic sludge removal is
required.
Anode Paste Plant
Fabrication of prebaked and Soderberg anodes takes place in the
anode paste plant where coal tar pitch and ground petroleum coke
are blended together to form paste. During electrolysis, the
prebaked anode is gradually consumed and becomes too short to be
effective. The resulting anode "butts," as they are commonly
referred to, are recycled for use in the paste plant. Operations
included in the paste plant are crushing, screening, calcining,
grinding, and mixing. The paste is then formed into briquettes
(for use in Soderberg cells) or into green prebake anodes. At
this stage, briquettes and green anodes are essentially the same,
where the principal difference between the two is size.
Briquettes are formed through an extrusion process in which the
paste is forced through a die and then chopped into small pieces
(briquettes) using a dicer. Green anodes, which are much larger
than briquettes, are formed by pressing paste into a mold.
Vibration may also be used. After forming, cooling water is used
to quench the briquettes or anodes to facilitate handling. There
are eleven plants that report using anode or briquette cooling
water.
Paste plant air pollution control usually consists of dry removal
of dust, although four plants use wet scrubbers. There are eight
plants using dry air pollution control devices; however, only one
of these is used to control emissions from the paste blending
area. Emissions from the paste blending area contain high
loadings of organics and are normally controlled with wet
scrubbers.
Carbon liners for the cell bottom are normally manufactured off-
site. However, the carbon liner is sealed into the cell by
ramming paste into the cracks and seams of the liner. Two plants
reported using wet scrubbers to control emissions during the
blending of cathode paste.
633
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PRIMARY ALUMINUM SUBCATEGORY SECT - III
Anode Bake Plant
Anodes used in prebake potline cells are baked prior to their use
in the potline. Two basic furnaces are used to bake anodes: ring
furnaces and tunnel kilns. The ring furnace consists of
compartmentalized, sunken, brick baking pits with surrounding
interconnecting flues. Green anodes are packed into the pits,
with a blanket of coke or anthracite filling the space between
the anode blocks and the walls of the pits. A 10 to 12 inch
blanket of calcined petroleum coke fills the top of each pit
above the top layer of anodes. The blanket helps to prevent
oxidation of the carbon anodes.
Each pit is baked for a period of about 40 to 48 hours. The flue
system of the furnace is arranged so that hot gas from the pits
being baked is drawn through the next section of pits to
gradually preheat the next batch of anodes before they are baked.
Air for combustion is drawn through the sections previously
baked, cooling them down. The anodes are baked at approximately
1,200°C, and the cycle of placing green anodes, preheating,
baking, cooling, and removal is approximately 28 days. Roughly
40 percent of the anode is volatilized during the baking cycle.
Baking of sections proceeds down one side of the rectangular
furnace building and back up the other in a "ring" pattern.
Proceeding around the building, the pattern of sections cooling
down, sections being baked, sections heating up, and empty
sections is repeated several times.
Ring furnaces use outside flues under draft, and since the flue
walls are of dry-type construction, most volatile materials
released from the anodes during the baking cycle (principally
hydrocarbons from the pitch binder) are drawn, with the
combustion products of the firing, into the flue gases where they
are burned at about 1300°C.
Gaseous emissions are composed primarily of fluoride (present due
to the recycle of anode butts) and hydrocarbons which are
controlled through either wet scrubbers or dry scrubbers using
alumina. Five plants reported using wet scrubbers to control air
pollution, while 12 plants utilize dry systems.
The baked anodes are stripped from the furnace pits by means of
an overhead crane on which pneumatic systems for loading and
removing the coke pit packing may also be mounted. The packing
may subsequently become part of other green anodes in the carbon
plant.
Ring furnaces can be further subdivided into open and closed top
furnaces. A closed top furnace is covered with a movable
refractory arch lid. An open top furnace is characterized by the
absence of the refractory lid. Removal of the lid from a closed
top furnace interrupts the flow path, drawing the volatiles up
through the packing material and directly into the flue. This
634
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PRIMARY ALUMINUM SUBCATEGORY SECT - III
method of operation increases flue life and decreases fuel
consumption because less air is required. It is reported that
about one-third less gases are processed in the closed top
furnace.
A second type of furnace, the tunnel kiln, has been developed for
baking anodes. The kiln is an indirect-fired chamber in which a
controlled atmosphere is maintained to prevent oxidation of the
carbon anodes. Green anode blocks are loaded on transporter
units that enter the kiln through an air lock, pass successively
through a preheating zone, a baking zone, and a cooling zone, and
leave the kiln through a second air lock. The refractory beds of
the cars are sealed mechanically to the kiln walls to form the
muffle chamber, and yet permit movement of the units through the
kiln.
The muffle chamber is externally heated by combustion gases and
the products of combustion are discharged through an independent
stack system. Effluent gases from the baking anodes may be
introduced into the fire box so as to recover the fuel value of
hydrocarbons and reduce the quantity of unburned hydrocarbon to
approximately 1 percent of that coming from a ring furnace.
Although the tunnel kiln presents mechanical problems in design
and operation, it is reported to have several appreciable
advantages over the ring type of furnace:
1. Baking cycle from green to finished anode is much
shor ter.
2. Anode baking is more uniform.
3. Space requirements for equal capacity furnaces are less.
4. Smaller gas volumes are handled through the furnace
emission control system.
The tunnel kiln in this application is used at only one primary
aluminum plant.
Baked anodes are delivered to air blast cleaning machines
utilizing fine coke as blasting grit. Fins, scrafs, and adherent
packing is removed by this treatment, and the baked anodes are
then transferred to the rod shop where the electrodes are
attached.
Cathode Reprocessing
A detailed description of cathode reprocessing will not be
presented due to confidentiality constraints. However, a brief
process description is possible and is sufficient for purposes of
understanding the regulations that apply to this unit process.
Spent potliners (cathodes) from the electrolytic cells are
disposed of through landfilling, indefinite "storage," or cathode
reprocessing. Cathode reprocessing serves a hazardous waste
treatment function by reducing waste volume, and incidentally
recovering cryolite. In cathode reprocessing, the spent
635
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PRIMARY ALUMINUM SUBCATEGORY SECT - III
potliners are ground in a ball mill and then leached with caustic
to solubilize fluoride. Undigested cathode material is separated
from the leachate using sedimentation and then sent to lagoons.
Sodium aluminate (NaAl02) is then added to the leachate to
initiate the precipitation of cryolite (Na3AlFg) and a second
solid-liquid separation is performed to recover cryolite, which
can be reused in the electrolytic cell. Lime is added to the
supernatant to precipitate calcium fluoride and a third solid-
liquid separation is performed. The resulting supernatant is
then routed back to the front of the process and used for
leaching. Blowdown from the system varies from plant to plant,
but it is universally used as potline scrubber liquor make-up
when wet potline scrubbers are used. It is also common to route
potline scrubber liquor through the cathode reprocessing circuit.
In this way, fluoride concentrations of the scrubber liquor are
controlled and recycle is possible.
PROCESS WASTEWATER SOURCES
The principal wastewater sources in the primary aluminum
subcategory are:
1. Anode and cathode paste plant wet air pollution control,
2. Anode bake plant wet air pollution control,
4. Cathode reprocessing,
5. Anode and briquette contact cooling,
6. Potline wet air pollution control,
7. Potline SO2 wet air pollution control,
8. Potroom wet air pollution control,
8. Degassing wet air pollution control,
9. Pot repair and pot soaking,
10. Direct chill casting contact cooling,
11. Continuous rod casting contact cooling, and
12. Stationary and shot casting contact cooling.
OTHER WASTEWATER SOURCES
Other wastewater streams may be associated with the manufacture
of primary aluminum, or found at primary aluminum facilities.
These wastewater streams may include coke plant contact cooling
water, courtyard and rooftop spray water, paste bucket wash
water, maintenance and cleanup water, stormwater runoff, and
spent potliner leachate. With the exception of spent potliner
leachate, these waste streams are not considered as a part of
this rulemaking. EPA believes that the flows and pollutant
loadings associated with these waste streams are either "too
insignificant to warrant a discharge allowance" or are best
handled by the appropriate permit authority on a case-by-case
basis under authority of Section 402 of the Clean Water Act.
While EPA believes that spent potliner leachate is best handled
by the appropriate permit authority on a case-by-case basis, EPA
has provided guidance to permit writers on the issue of leachate
treatment performance values (See Section X of this document and
636
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PRIMARY ALUMINUM SUBCATEGORY
SECT -
III
52 FR 25554). That guidance states that spent potliner leachate
may receive the treatment performance values developed for
cathode reprocessing or potline scrubber liquor commingled with
cathode reprocessing wastewaters provided that the permit writer
determines, on a case-by-case basis, that the wastewater matrices
of cathode reprocessing and spent potliner leachate are
comparable. Also, the spent potliner leachate may not be
commingled with process or nonprocess wastewaters other than
cathode reprocessing or potline wet air pollution control
operated in conjunction with cathode reprocessing. Spent
potliner leachate resulting from atmospheric precipitation is
considered to be a site-specific, non-scope waste stream by the
Agency. As such, specific limitations are not provided for this
waste stream in 40 CFR Part 421, 80421.23, 421.24, and 421.26.
AGE, PRODUCTION, AND PROCESS PROFILE
Figure III-2 (page 642) shows the location of the 31 primary
aluminum reduction plants operating in the United States.
Because considerable amounts of electrical energy are required to
produce aluminum, most primary aluminum plants are located near
sources of abundant and inexpensive hydroelectric power, such as
the Pacific Northwest and the Tennessee River Valley.
Of the 31 reduction plants listed in Table III-l, (page 638) 22
plants (70 percent) were built in the last 33 years. The average
plant age is between 20 and 30 years. The data summarized in
Table III-2 (page 639) indicate that 27 of the 31 plants (85
percent) produce less than 200,000 tons per year each. Median
production is in the 100,000 to 150,000 tons per year range.
Table III-3 (page 640) provides a summary of the number of plants
generating wastewater for the waste streams associated with the
various processes and the number of plants with the process.
637
-------
Table III-1
INITIAL OPERATING YEARS (RANGE) SUMMARY OF PLANTS
IN THE PRIMARY ALUMINUM SUBCATEGORY BY DISCHARGE TYPE
Plant A%e Ran^e (Years)
u>
CD
Type of Plant
Discharge
1982-
1973
0-10
1972-
1968
10-15
1967-
1958
15-25
1957-
1948
25-35
1947-
1938
35-45
1937-
1918
45-65
1917-
1903
65-80
Before
1903
80+
Total
Direct
1
6
4
7
8
0
1
0
27
Zero
J.
_0
_0
_3
_0
_0
_0
_0
_4
Tota 1
2
6
4
10
8
0
1
0
31
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-------
PRIMARY ALUMINUM SUBCATEGORY SECT - III
Table III-2
PRODUCTION RANGES FOR THE PRIMARY ALUMINUM SUBCATEGORY
Production Ranges
for 1976 (tons/year) No. of Plants
0 - 50000 2
50001 - 100000 9
100001 - 150000 9
150001 - 200000 7
200001 - + 3
Not Reported 1
Total Number of Plants 31
in Survey
639
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PRIMARY ALUMINUM SUBCATEGORY SECT - III
Table III-3
SUMMARY OF SUBCATEGORY PROCESSES AND ASSOCIATED WASTE STREAMS
Process
Electrolytic Reduction
Potline Air Pollution Control
Potline SO2 Air Pollution Control
Potroom Air Pollution Control
Anode Paste Plant
Anode Paste Plant Air Pollution
Control
Anode Bake Plant
Anode Bake Plant Wet Air Pollution
Control
Anode Contract Cooling and Briquette
Quenching
Cathode Reprocessing
Pot Repair and Pot Soaking
Refining
Degassing Air Pollution Control
Casting
Direct Chill Casting
Continuous Rod Casting
Stationary Casting
Shot Casting
Number of
Plants with
Process
31
28
2
8
29
26
20
17
11
4
31
13
6
26
3
8
1
Number of Plants
Generating
Wastewater
9
2
8
11
4
5*
26
3
0
1
* Number of Plants known to discharge pot soaking and pot repair
wastewater.
640
-------
Coke
o\
Ano«|e ,md C.nliodr
P-iMli- Rlending
Rr Iq-'Pt to Cent Ing
u-»r ni
Pf Iqil^t t e
H.innf nrtnrn
V-
Crushing
CI ass I f y Ing
Anode
CoolIng
Water
Prebakei
Pressing and
Baking
Sodcrberg Anodes
Alumlnn
Cryolite, (ChF2, A1F2>
Direct Current
F1.ECTR0I.YTIC
CELL
Disposal
Spent Cathode*
Caustic and "olllne
Scruhher l.lquor
i-
Mo!ten
AIumlnum
Pot!lne and
Pot room A1r
Pollution Control
Liquor
Cathode
Reprorenqlng
Sol 1Hft to
Rlowdowii to Potllne
or discharge
Cl.^ or Mixed Cnses-
Degvtas Ing
Ca<«r Ing
CoolIng
A r r 1 vat ed
Alumina
Adsorption
Alumina to F.ler t rt»1 yt lc Cell
V-
Scruhher
l.lquor
Coo|Ing Water
AlumInun
(Pig, Billet, Ingot and Rod)
Raghouse
Paste Plant
Air Po 11 lit I on
Control
Rake Plant
Air Pol In11 on
Cont rol
SoI Ids to
' Her yr le
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l.lquor
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52
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Figure III-1
PRIMARY ALUMINUM REDUCTION PROCESS
-------
S DUN
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50
>
f
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C
Cd
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D-Dirnct Process Wastewater Discharge Plants
Z-Zero Process Wastewater Discharge Plants
Figure I1I-2
GEOGRAPHIC LOCATIONS OF PRIMARY ALUMINUM REDUCTION PLANTS
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - IV
SECTION IV
SUBCATEGORIZATION
This section summarizes the factors considered during the
designation of the primary aluminum subcategory and its related
subdivisions. Primary aluminum was considered as a single
subcategory during the previous 1974 rulemaking.
FACTORS CONSIDERED IN SUBDIVIDING THE PRIMARY ALUMINUM
SUBCATEGORY
The factors listed for general subcategorization were each
evaluated when considering subdivision of the primary aluminum
subcategory. In the discussion that follows, the factors will be
described as they pertain to this particular subcategory.
The rationale for considering segmentation of the primary
aluminum subcategory is based primarily on the production process
used. Within this subcategory, a number of different operations
are performed, which may or may not have a water use or
discharge, and which may require the establishment of separate
effluent limitations and standards. While primary aluminum
smelting is still considered a single subcategory, a more
thorough examination of the production processes, water use and
discharge practices, and pollutant generation rates has
illustrated the need for limitations and standards based on a
specific set of waste streams. Limitations and standards will be
based on specific flow allowances for the following subdivisions:
1. Anode and cathode paste plant wet air pollution
control,
2. Anode bake plant wet air pollution control,
3. Cathode reprocessing,
4. Anode and briquette contact cooling,
5. Potline wet air pollution control,
6. Potline SO2 wet air pollution control,
7. Potroom wet air pollution control,
8. Degassing wet air pollution control,
9. Pot repair and pot soaking,
10. Direct chill casting contact cooling,
11. Continuous rod casting contact cooling, and
12. Stationary and shot casting contact cooling.
OTHER FACTORS
A number of other factors considered in this evaluation and were
shown to be an inappropriate bases for further segmentation.
These are discussed briefly below.
Type of Ar.ode
As described in Section III, there are two anode types used by
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - IV
the primary aluminum subcategory; prebaked and Soderberg. The
type of anode used determines the wastewater source in which
particular toxic organic pollutants appear. In plants using
prebaked anodes, toxic organic pollutants have been observed in
wastewater from wet air pollution control devices associated with
the anode bake plant and in plants using Soderberg anodes, toxic
organics have been observed in potline and potroom wet air
pollution control devices. However, the concentrations of the
toxic organics observed in both wastewater sources were at
similar levels, requiring similar treatment (refer to Sections V
and VII). Accordingly, subdivision of the category by anode type
was rejected.
Plant Size
A review of the 31 aluminum reduction plants showed that 11
plants have capacities of less than 90,000 metric tons (100,000
short tons) per year, 16 plants have capacities between 90,000
and 180,000 metric tons (100,000 and 200,000 short tons per
year), and three plants have capacities greater than 180,000
metric tons (200,000 short tons) per year. No factors relating
to this distribution of plant size and pertaining to a given
plant's ability to achieve effluent limitations have been
identified.
Plant Age
Primary aluminum smelting is a relatively new industry based on a
single process. Therefore, the oldest plants built in the early
1940's are electrochemically equivalent to those built today;
however, numerous modifications have been made in process
operation which have resulted in greater production efficiency
and reduced air pollutant emissions. As a result, neither the
concentration of constituents in wastewater nor the capability to
meet the limitations is related to plant age. Because of the
general uniformity of aluminum process technology, the
application of most environmental control methods and systems
that have been developed is dependent on factors other than age
(i.e., for the Hall process, the most recently developed unit
operations are used, and these can be retrofitted independently
of plant age).
Product
Primary aluminum smelters produce aluminum metal and various
aluminum alloys. Some plants carry out an additional refining
step to produce higher purity aluminum, and a few plants also
carry out rolling and wire-drawing operations. The fabrication
operations rolling, drawing, forging, and extrusion are covered
under a separate point source category.
PRODUCTION NORMALIZING PARAMETERS
As discussed previously, the effluent limitations and standards
developed in this document establish mass limitations on the
644
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PRIMARY ALUMINUM SUBCATEGORY SECT - IV
discharge of specific pollutant parameters. To allow these
limitations and guidelines to be applied to plants with various
production capacities, the mass of pollutant discharged must be
related to a unit of production. This factor is known as the
production normalizing parameter (PNP). In general, the amount
of aluminum produced by the respective manufacturing process is
used as the PNP. This is based on the principle that the amount
of water generated is proportional to the amount of product made.
The PNP's for the 12 subdivisions are displayed in Table VI-1
(page 659). Other PNPs were considered for certain subdivisions;
however, they were rejected. They are discussed below.
ANODE AND CATHODE PASTE PLANT WET AIR POLLUTION CONTROL
The production normalizing parameter selected for this
segment is the actual paste production, as metric tons (short
tons) of paste. Overall aluminum reduction capacity, although
considered as a parameter, was rejected; since some plants sell
paste and anodes to other plants, it is difficult to ascertain
which plants were selling and which plants were purchasing.
Records are available, however, that detail paste plant capacity
and production levels. Capacity, rather than actual paste
production, was considered for use because the water use and
discharge rates reported by the plants were for a year when
capacity utilization in the primary aluminum subcategory was
abnormally low. When analytical samples were taken, however, the
pollutant concentration calculations were based on actual
measured flows and production rates. In order to be consistent
when determining pollutant loadings, the actual paste production
was chosen as the production normalizing parameter. Use of
actual paste production also eliminates the need for plants to
reduce water flow during years in which actual production is
greater than design capacity.
CATHODE REPROCESSING
The production normalizing parameter proposed for this
subdivision was the amount of aluminum produced from electrolytic
reduction. The Agency has learned since proposal that certain
primary aluminum plants may process cathodes from other plants as
a hazardous waste treatment operation. Consequently, the
aluminum produced from electrolytic reduction is an inappropriate
production normalizing parameter. A more suitable production
normalizing parameter is the amount of cryolite recovered during
cathode reprocessing. In this way, cathode reprocessing becomes
independent of the reduction process so that cathodes from other
plants may be brought to one site for processing.
POTLINE, POTLINE SO2, AND POTROOM WET AIR POLLUTION CONTROL
Most plants use wet or dry scrubbing over an entire potline or
potroom (i.e., the off-gases are collected, and centralized
scrubbers are used to control the emissions). Occasionally,
though, a plant may use wet scrubbers on only one of their
potlines. Therefore, the production normalizing parameter
645
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PRIMARY ALUMINUM SUBCATEGORY SECT - IV
selected for these subdivisions is the amount of aluminum
produced from electrolytic reduction. If wet scrubbers are only
used on a particular potline, the amount of aluminum produced is
based on the electrolytic reduction in that potline. Although it
should be noted that actual aluminum production from electrolytic
reduction can exceed rated capacity, this is generally achievable
only with a loss in current efficiency. Discussions with plant
personnel indicated that capacity might be a more appropriate
measure than actual aluminum production from electrolytic
reduction because when the potline is operating, water use is
relatively constant (i.e., water use is not adjusted for
production rates). When an entire potline is shut down, then the
scrubbers are shut down as well. Consistency in the application
of sampling data, however, necessitated the use of aluminum
production from electrolytic reduction as the production
normalizing parameter. This will ensure that higher capacity
utilization will not reduce the production normalized flow
allowance for this operation.
646
-------
1
2
3
4
5
6
7
8
9
10
11
12
PRIMARY ALUMINUM SUBCATEGORY SECT - IV
TABLE IV
PRODUCTION NORMALIZ
Subdivision
Anode and cathode paste plant
wet air pollution control
Anode bake plant wet air
pollution control
Anode and briquette contact
cooling
Cathode reprocessing
Potline wet air pollution
cont rol
Potline SO2 wet air
pollution control
Potroom wet air pollution
control
Degassing wet air pollution
control
Pot repair and pot soaking
Direct chill casting contact
cooling
Continuous rod casting
contact cooling
Stationary or shot casting
contact cooling
PARAMETERS
PNP
kkg o£ paste produced
kkg of anodes baked
kkg of anodes or briquettes
cast
kkg of cryolite produced
from cathode reprocessing
kkg of aluminum produced
from electrolytic reduction
kkg of aluminum produced
from electrolytic reduction
kkg of aluminum produced
from electrolytic reduction
kkg of aluminum degassed
kkg of aluminum produced
from electrolytic reduction
kkg of aluminum product
from direct chill casting
kkg of aluminum product
from rod casting
kkg of aluminum product
from stationary or shot
casting
647
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PRIMARY ALUMINUM SUBCATEGORY
SECT - IV
THIS PAGE INTENTIONALLY LEFT BLANK
648
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - V
SECTION V
WATER USE AND WASTEWATER CHARACTERISTICS
This section describes the characteristics of wastewater
associated with the primary aluminum subcategory. Data used to
quantify wastewater flow and pollutant concentrations are
presented, summarized, and discussed. The contribution of
specific production processes to the overall wastewater discharge
from primary aluminum plants is identified whenever possible.
This information was used primarily to identify principal sources
of wastewater in the category and to determine if pollutants were
present in treatable concentrations. Treatment performance
concentrations were developed from different data bases.
Three principal data sources were used in the development of the
effluent limitations and standards for this subcategory: data
collection portfolios (dcp), field sampling results and comments
and associated specific data requests. Data collection
portfolios, completed for each of the primary aluminum plants,
contain information regarding wastewater flows and production
levels.
In order to quantify the pollutant discharge from primary
aluminum plants, a field sampling program was conducted.
Wastewater samples were collected in two phases: screening and
verification. The first phase, screen sampling, was to identify
which toxic pollutants were present in the wastewaters from
production of the various metals. Screening samples were
analyzed for 125 of the 126 toxic pollutants and other pollutants
deemed appropriate. Because the analytical standard for TCDD
was judged to be too hazardous to be made generally available,
samples were never analyzed for this pollutant. There is no
reason to expect that TCDD would be present in aluminum smelting
wastewater. A total of 10 plants were selected for screen
sampling in the nonferrous metals manufacturing category. A
complete list of the pollutants considered and a summary of the
techniques used in sampling and laboratory analyses are included
in Section V of the General Development Document. In general,
the samples were analyzed for three classes of pollutants: toxic
organic pollutants, toxic metal pollutants, and criteria
pollutants (which includes both conventional and nonconventional
pollutants ) .
As described in Section IV of this supplement, the primary
aluminum subcategory has been further segmented into 12 building
blocks, so that the promulgated regulation contains mass
discharge limitations and standards for 12 process wastewaters.
Differences in the wastewater characteristics associated with
these building blocks are to be expected. For this reason,
wastewater streams corresponding to each segment are addressed
separately in the discussions that follow.
649
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PRIMARY ALUMINUM SUBCATEGORY SECT - V
WASTEWATER SOURCES, DISCHARGE RATES, AND CHARACTERISTICS
The wastewater data presented in this section were evaluated in
light of production process information compiled during this
study. As a result, it was possible to identify the principal
wastewater sources in the primary aluminum subcategory. These
include:
1. Anode and cathode paste plant wet air pollution
control,
2. Anode bake plant wet air pollution control,
3. Anode and briquette contact cooling,
4. Cathode reprocessing,
5. Potline wet air pollution control,
6. Potline SO2 wet air pollution control,
7. Potroom wet air pollution control,
8. Refining and degassing wet air pollution control,
9. Pot repair and pot soaking,
10. Direct chill casting contact cooling water,
11. Continuous rod casting contact cooling water, and
12. Stationary and shot casting contact cooling water.
Data supplied by dcp responses (and special requests) were
evaluated, and two flow-to-production ratios were calculated for
each stream. The two ratios, water use and wastewater discharge
flow, are differentiated by the flow value used in calculation.
Water use is defined as the volume of water or other fluid (e.g.,
emulsions, lubricants) required for a given process per mass of
aluminum product and is therefore based on the sum of recycle and
make-up flows to a given process. Wastewater flow discharged
after pretreatment or recycle (if these are present) is used in
calculating the production normalized flow—the volume of
wastewater discharged from a given process to further treatment,
disposal, or discharge per mass of aluminum produced.
Differences between the water use and wastewater flows associated
with a given stream result from recycle, evaporation, and
carryover on the product. The production values used in
calculation correspond to the production normalizing parameter,
PNP, assigned to each stream, as outlined in Section IV. The
production normalized flows were compiled and statistically
analyzed by stream type. Where appropriate, an attempt was made
to identify factors that could account for variations in water
use. This information is summarized in this section. A similar
analysis of factors affecting the wastewater values is presented
in Sections X, XI, and XII where representative BAT, BDT, and
pretreatment discharge flows are selected for use in calculating
the effluent limitations and standards. As an example, potline
air scrubbing waste water flow is related to the potline
production. As such, the discharge rate is expressed in liters
of scrubber wastewater per metric ton cf potline production
(gallons cf scrubber water per ton of potline production).
The methods used in evaluation of wastewater data varied as
dictated by the intended use of the results. For example, in
Section VI the wastewater data from effluent samples are examined
650
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PRIMARY ALUMINUM SUBCATEGORY
SECT - V
to select pollutants for consideration in regulating the
category.
In order to quantify the concentrations of pollutants present in
wastewater from primary aluminum plants, wastewater samples were
collected at six plants, representing 22 percent of the
discharging primary aluminum plants. Diagrams indicating the
sampling sites and contributing production processes are shown in
Figures V-l to V-6 (pages 718 to 723).
The raw wastewater sampling data for the primary aluminum
subcategory are presented in Tables V-2, 4, 6, 8, 10, 13, 15, and
20 (pages 660, 663, 666, 669, 675, 679, 687, 693, respectively).
Miscellaneous wastewater sampling data are presented in Table V-
21 (page 695). Treated wastewater sampling data are shown in
Tables V-22 through V-27 (pages 701 to 710). The stream codes
displayed in Tables V-12 through V-27 (pages 680 to 710) may be
used to identify the location of each of the samples on the
process flow diagrams in Figures V-l to V-6 (pages 718 to 723).
Where no data are listed for a specific day of sampling, the
wastewater samples for the stream were not collected. If the
analysis did not detect a pollutant in a waste stream, the
pollutant was omitted from the table.
The data tables include some samples measured at concentrations
considered not quantifiable. The base-neutral extractable, acid
extractable, and volatile organics are generally considered not
quantifiable at concentrations equal to or less than 0.010 mg/1.
Below this concentration, organic analytical results are not
quantitatively accurate; however, the analyses are useful to
indicate the presence of a particular pollutant. The pesticide
fraction is considered nonquantifiable at concentrations equal to
or less than 0.005 mg/1. Nonquantifiable results are designated
in the tables with an asterisk (double asterisk for pesticides).
These detection limits shown on the data tables are not the same
in all cases as the published detection limits for these
pollutants by the same analytical methods. The detection limits
used were reported with the analytical data and hence are the
appropriate limits to apply to the data. Detection limit
variation can occur as a result of a number of laboratory-
specific, equipment-specific, and daily operator-specific
factors. These factors can include day-to-day differences in
machine calibration, variation in stock solutions, and variation
in operators.
The statistical analysis of data includes some samples measured
at concentrat ions considered not quantifiable. Data reported as
an asterisk are considered as detected but below quantifiable
concentrations, and a value of zero is used for averaging. Toxic
organic, nonconventiona1, and conventional data reported with a
"less than" sign are considered as detected, but not further
quantifiable. A value of zero is also used for averaging. If a
pollutant is reported as not detected, it is excluded in
calculating the average. Finally, toxic metal values reported as
651
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - V
less than a certain value were considered as not detected, and a
value of zero is used in the calculation of the average. For
example, three samples reported as ND, *, and 0.021 mg/1 have an
average value of 0.010 mg/1. The averages calculated are
presented with the sampling data. These values were not used in
the selection of pollutant parameters.
The method by which each sample was collected is indicated by
number, as follows.
1 one-time grab
2 24-hour manual composite
3 24-hour automatic composite
4 48-hour manual composite
5 48-hour automatic composite
6 72-hour manual composite
7 72-hour automatic composite
In the dcps, plants were asked to indicate whether or not any of
the toxic pollutants were believed to be present in their
wastewater. Responses for the toxic organic compounds selected
as pollutant parameters and toxic metals considered for
regulation are summarized in Table V-28 (page 712) for those
plants responding to that portion of the dep. Although most of
the plants indicated that these compounds were believed to be
absent, several did report that they believed specific pollutant
parameters were present in their wastewater.
ANODE AND CATHODE PASTE PLANT WET AIR POLLUTION CONTROL
Plants manufacturing Soderberg and prebaked anodes blend coal tar
pitch and ground coke (metallurgical and petroleum) to form anode
paste. Plants may also prepare cathode paste to seal the seams
the cathode to prevent iron contamination. These raw materials
are crushed, screened, calcined, ground, and blended in the paste
plant. This series of operations results in the formation of
particulates, tars, oils, and hydrocarbons through degradation of
the pitch and coke. Four of the 29 facilities with paste plants
report the use of wet scrubbers to control the emission of these
pollutants while 22 report the use of dry air pollution control.
Anode paste plant wet air pollution control discharge levels are
in liters/metric ton (1/kkg) (gal/ton) of paste produced, as
shown in Table V-l (page 659).
Plants using wet air pollution control on the paste plant
generally do so to control fugitive hydrocarbon emissions. The
variation in the production normalized flows shown in Table V-l
may be a result of the degree of hydrocarbon control required in
each plant.
Table V-2 (page 660) summarizes the field sampling data for the
toxic and selected conventional and r.onconventional pollutants
detected. This waste stream is characterized by the presence of
the toxic organics acenaphthene, naphthalene, fluoranthene,
652
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - V
benzo(a)anthracene, chrysene, phenanthene, fluorene, and pyrene
(all above 1 mg/1) and the conventional pollutant, oil and grease
(25 to 1,900 mg/1). These specific pollutants are present as a
result of the crushing, screening, and calcining of the pitch and
coke.
ANODE BAKE PLANT WET AIR POLLUTION CONTROL
Of the 20 primary aluminum plants with anode bake plants, five
utilize wet air pollution controls on anode bake furnaces. The
water, discharge rates for anode bake plant air pollution control
are shown in Table V-3 (page 662). Suspended solids, oil and
grease, sulfur compounds and fuel combustion products
characterize this effluent stream. Fluorides may also be
introduced in plants where recycle of anode "butts" is practiced.
The toxic organic pollutants found in anode paste plant wet air
pollution control wastewater are also present in anode bake plant
wet air pollution control samples. These pollutants evolve
during the baking of green anodes in the bake plant, and as
such are present in the wastewater. Anode bake plant sampling
data are presented in Table V-4 (page 663).
ANODE AND BRIQUETTE CONTACT COOLING
Eleven plants report the use of water for cooling green anodes
and briquettes prior to their introduction into the electrolytic
cell. Three of the 11 plants use contact cooling water for
Soderberg briquettes. Water discharge rates for the 11 plants
reporting the anode contact cooling wastewater stream are
presented in liters per metric ton of anode cast in Table V-5
(page 665). This waste stream is characterized by the presence of
many of the toxic organics discussed above but at reduced
concentrations (0.04 to 0.08 mg/1). The raw wastewater data for
this stream are shown in Table V-6 (page 666).
CATHODE REPROCESSING
The electrolytic pot is lined with a cathode manufactured from
anthracite coal. Upon the failure of a cathode, the pot is taken
out of production, emptied, rinsed, and the liner is removed. The
cathode is then transferred to cathode reprocessing where it is
ground and leached with caustic to solubilize fluoride. Cryolite
is precipitated from the leachate by the addition of sodium
aluminate. (The operation is conducted to treat hazardous waste
as well as to recover cryolite). The water discharge rates
reported for cathode reprocessing, in liters per metric ton of
cryolite recovered, are shown in Table V-7 (page 668). Due to
the raw materials used to manufacture the cathode, this waste
stream is characterized by the presence of toxic organic
pollutants (less than 0.05 mg/1). Fluoride (63 to 13,000 mg/1),
cyanide (58 to 129 mg/1), and total suspended solids (19 to
54,500 mg/1) are also present. The presence of cyanide results
from the electrolytic process where high temperatures and a
reducing environment induce the formation of cyanide from carbon
and nitrogen. The raw wastewater data are shown in Table V-8
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - V
(page 669).
POTLINE WET AIR POLLUTION CONTROL
For potline emissions, the water use and discharge in liters per
metric ton of aluminum from electrolytic reduction production are
shown in Table V-9 (page 674). Flow rates are only based on the
production of those potlines controlled by a wet system. Raw
wastewater characterization data for potline wet air pollution
control, as shown in Table V-10, (page 675) are from samples
taken at three primary aluminum plants. Waste streams from
potline wet scrubbers or wet electrostatic precipitators contain
suspended solids, fluorides and several toxic pollutants.
Suspended solids result from dust associated with alumina and
cryolite addition to the electrolytic cell. Fluoride results
from the use of cryolite, a fluoride salt in the cell. Organic
pollutants present can be attributed to anode oxidation. In
addition, toxic metal impurities in the alumina can be introduced
into this waste stream. These are introduced as part of the dust
evolving from the anode.
POTLINE SO2 WET AIR POLLUTION CONTROL
Two plants currently use sodium scrubbers to control sulfur
dioxide emissions from potlines. In both instances the scrubbers
follow dry fluoride scrubbing systems. Although the Agency has
not sampled this wastewater source, it will contain similar
pollutants as potline wet air pollution control, but at much
smaller concentrations. Dry fluoride scrubbing systems are
reported to have efficiencies approaching 99.9 percent removal of
fluoride and 80 percent of organic emissions. Therefore, this
waste stream is expected to be relatively pollutant free, with a
pH between 6 and 7. Water use rates on a production normalized
basis are presented in Table V-ll (page 679).
POTROOM WET AIR POLLUTION CONTROL
For potroom emissions control devices, the anode type, water use,
and water discharge rates, in liters per metric ton of aluminum
from electrolytic reduction, are shown in Table V-12 (page 680).
Flow rates are only based on production levels of potlines
controlled by a wet system. As can be seen in Table V-13, (page
681) potroom air pollution control wastewater streams contain
pollutants similar to those associated with the potlines at
reduced concentrations. This is due to the fact that air
circulated through potroom scrubbing systems is diluted as it
passes from the pots through the air space above the potline to
the scrubbing system in the roof.
DEGASSING WET AIR POLLUTION CONTROL
Most aluminum reduction plants degas molten aluminum before cast-
ing. Degassing is usually accomplished by bubbling a gas
(chlorine, nitrogen, argon, or a combination of these elements)
through the melt. The reported water use and discharge rates for
654
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - V
degassing wet air pollution control, in liters per metric ton of
aluminum degassed, are shown in Table V-14 (page 686). Raw
wastewater from this waste stream is characterized by the
presence of toxic metals at very low concentrations. The raw
wastewater data are shown in Table V-15 (page 687).
POT REPAIR AND POT SOAKING
Periodically electrolytic cells fail, and the carbon liner or
cathode is removed. Generally water is used to soften the liner
and to facilitate removal. Water dumped from the cell will
contain cyanide and fluorides similar to cathode reprocessing
wastewater. Analytical data supplied by industry representatives
show TSS concentrations ranging from 10-400 mg/1' and fluoride
ranging from 1,800-7,000 mg/1. Cyanide was reported as 438 mg/1.
Data on water use for this process are limited. Several plants
were contacted through Section 308 authority after proposal to
try to quantify water usage. Data were received from only one
company, indicating water usage rates of 710 1/kkg to 3.3 1/kkg
of aluminum reduced. Additional water use data were taken from
the dcp and comments.on the draft development document. Another
plant visited by the Agency was designed as a zero discharge
system through 100 percent reuse. Conversations with industry
personnel indicate this operation is normally a zero discharge
operation through continued reuse of the soaking water. Three
plants are known to reuse 100 percent of their pot soaking-pot
repair wastewater. Water usage rates are presented in Table V-
16 (page 688).
CASTING CONTACT COOLING WATER
Contact cooling water may be used for casting. The cooling water
is frequently recycled but may require a bleed stream (blowdown)
to dissipate the buildup of dissolved solids. There are four
principal types of casting used in the primary aluminum
subcategory: direct chill, stationary, shot, and continuous rod.
Twenty-six primary aluminum plants practice direct chill casting,
eight plants practice stationary casting, one has shot casting,
and three plants have continuous rod casting operations. In the
stationary casting method, molten aluminum is poured into cast
iron molds and then generally allowed to air cool. The Agency is
aware of the use of spray quenching to quickly cool the surface
of the molten aluminum once it is cast into the molds; however,
this water evaporates on contact with the molten aluminum. As
such, the Agency believes that there is no basis for a pollutant
discharge allowance. The water use and discharge rates for
direct chill and continuous rod casting operations are shown in
Tables V-17 through V-19 (pages 689-692), in liters per metric
ton of aluminum cast. Organics, in the form of oil and grease
(and total phenolics (4-AAP)), may be found in these systems when
lubricants are applied. The variety and quantity of organics
will be dependent on the type of lubricant used. Sampling data
for a direct chill casting operation are presented in Table V-20
(page 693).
655
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - V
The data in the raw wastewater table show that, when compared to
the plant intake water analyses, over half of the raw wastewater
pollutants are nearly the same or only slightly higher (less than
one order of magnitude) than the intake water. Although the
sampling data in Table V-20 (page 693) is for direct chill
casting, contact cooling water from other types of casting will
have similar pollutant characteristics because the raw material,
aluminum, is the same in all four operations.
PILOT SCALE WASTEWATER TREATMENT STUDY
Subsequent to proposing amendments to the effluent limitations
and standards for the primary aluminum subcategory, the Agency
received numerous comments from companies in the primary aluminum
subcategory on the proposed mass limitations for benzo(a)pyrene
and cyanide. To respond to these comments, the Agency conducted
bench and pilot-scale tests on potline scrubber liquor and
cathode reprocessing wastewater to determine the effectiveness of
various wastewater treatment methods in removing polynuclear
aromatic hydrocarbons (PAH) and on the effectiveness of cyanide
precipitation in removing cyanide from cathode reprocessing and
potroom wet air pollution control wastewater. In the study, the
effectiveness of lime and settle, multimedia filtration, and
activated carbon were examined using bench scale and pilot scale
equipment in a trailer mounted wastewater treatment facility at a
primary aluminum plant in the northwestern United States.
PAH Treatment
The study demonstrated that PAH commonly found in primary
aluminum wastewaters can be removed using lime and settle
technology followed by multimedia filtration. In this study,
benzo(a)pyrene was removed to the quantification limit of 0.010
mg/1 by lime settle and filter technology. It was demonstrated
that activated carbon will also reduce benzo(a)pyrene to the
nominal quantification limit of 0.010 mg/1. Analytical results
of the study are presented in Tables V-29 through V-33 (pages 713
- 717) .
Data obtained from the pilot scale work were used to develop
achievable treatment concentrations for the various PAH using
lime and settle; lime, settle, and multimedia filtration; and
lime, settle, multimedia filtration, and activated carbon
adsorption treatment. These long-term average treatment
effectiveness concentrations were also used in recalculating
pollutant removal estimates.
For the model treatment technology, lime, settle, and filter, the
Agency calculated values of 0.0337 mg/1 for the daily maximum and
0.0156 mg/1 for the average monthly maximum. These values are
based on a statistical analysis of the treatability data for
benzo-(a)-pyrene obtained in the pilot study. These two values
account for variability in the pilot study and variability
inherent in the operation of lime, settle, and filter technology.
656
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - V
Potline scrubber liquor also contains treatable concentrations of
toxic metals (most notably antimony and nickel), fluoride,
aluminum, and suspended solids. Treatment performance for these
parameters was measured during the lime, settle, and filter tests
performed for the PAH. Results of the analyses are presented in
Tables V-32 and V-33 (pages 716 - 717).
As shown in Table V-33, BAT treatment performance for the
primary aluminum subcategory was not achieved. At the plant,
potline scrubber liquor is processed through the cathode
reprocessing circuit to reduce fluoride concentrations. The
bleed from cathode reprocessing is then routed back to the
potline scrubbing circuit. The cathode reprocessing wastewater,
and subsequently the potline scrubber liquor, contain dissolved
solids levels in the five to six percent range. It appears that
this significant matrix difference between cathode reprocessing
wastewater and other plant raw wastewaters used to develop the
treatment performance values contributes to less effective
performance of the treatment technology. Some of the
ramifications of this finding are discussed in detail in Section
X of this supplement.
Cyanide Treatment
Prior to performing the pilot scale work, laboratory (bench-
scale) studies were performed to identify the necessary reaction
steps and chemical quantities required to precipitate the cyanide
complexes present in the primary aluminum wastewater matrix. In
general, the Agency found that 75 to 90 percent of the cyanide is
present as a complex hexacyanoferrate. Thus, the primary
function of the laboratory work was to examine the methods and
variables affecting the conversion of free cyanide and
hexacyanoferrate (III) complexes to hexacyanoferrate (II) so that
cyanide complexes may be precipitated as prussian blue. A
general description of the operating procedures used in the lab
for cyanide precipitation is presented below:
1. Adjust pH to 9,
2. Add FeS04,
3. Rapid mix,
4. Adjust pH (3 to 5),
5. Add FeS04, FeCl3,
6. Rapid mix for 10 minutes,
7. Settle for one hour, and
8. Filter (pressure).
Information obtained in the laboratory was then tested on a pilot
scale level at a primary aluminum reduction facility using
cathode reprocessing wastewater.
Laboratory work performed by industry on cyanide bearing
wastewaters from two primary aluminum plants indicates that
ferric chloride addition does not increase the amount of cyanide
precipitated from the wastewater. As the ferrous sulfate dosage
was held constant, the ferric chloride addition was varied with
657
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - V
no noticeable increase in cyanide removal. This data tends to
indicate that ferric chloride addition has little or no effect on
the precipitation of iron cyanide complexes.
The Agency's pilot scale treatability studies revealed that the
treatability limits for cyanide precipitation are not
transferable from coil coating to the primary aluminum wastewater
matrix. The cryolite recovery operations discharge much higher
concentrations of cyanide than observed in coil coating and
impair treatment by also discharging extremely high dissolved
solids concentrations (five to six percent) that interfere with
precipitation chemistry.
From the pilot scale work it was determined that cyanide
precipitation can achieve 2.3 mg/1 cyanide, and the addition of
multimedia filtration will further reduce cyanide to 1.1 mg/1.
Since a full scale cyanide precipitation unit is not used
anywhere in the industry, the mean variability factors obtained
from the combined metals data base (CMDB) are used to calculate
the one-day maximum and ten day average concentrations. The
Agency received comments to the proposed regulation stating that
the transfer of the CMDB variability factors is not appropriate
because the precipitate formed during cyanide precipitation will
have different settling characteristics than the lime and metal
hydroxide sludge. However, since cyanide precipitation is not
currently run at full scale, the CMDB variability factors will be
used due to the lack of any other data.
658
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - V
TABLE V-l
WATER DISCHARGE RATES FOR ANODE AND CATHODE PASTE PLANT
WET AIR POLLUTION CONTROL
(1/kkg)
Percent Production Normalized
Plant Code Recycle Discharge Flow
353 0 2202
354 0 1434
365 0 754
369 0 817
659
-------
Table V-2
PRIMARY ALUMINUM SAMPLING DATA
ANODE PASTE PLANT WET AIR POLLUTION CONTROL
RAW WASTEWATER
a\
a\
o
St ream
Sample
Concent rat Ions
(mn/1)
Po1lut ant
_Code
T ypet
Source
Day 1
Day 2
Day 3
Average
Toxic Pollucancs(a)
t .
acenaphthene
144
3
*
29.0
12.0
ND
20.5
20.
2-chloronaphchalene
144
3
ND
0.041
ND
NU
0.041
39.
f luoranthene
1 44
3
*
8.0
3.6
1.5
5.0
42.
bls(2-chLoroIsopropyI) ether
144
3
ND
0.025
ND
*
0.01 3
55.
napht ha 1cnp
IV.
3
ND
7.7
1 .8
0.77
3.3
62.
N-nltrosodIphenyl amine
144
3
Nl)
0»057
*
*
0.2
66.
bls(2-ethylhexv1) phthalate
144
3
*
2.b
»
0.02 1
0.84
68.
dl-n-butyl phthalate
144
3
ND
*
ND
0.022
0.01 1
72.
benzo(a)anthracene
144
3
ND
1 .8
0.63
0. 78
1 . 1
73.
benzo(a)pyrene
1 44
3
NU
0.49
0.03
0.19
0.2
74.
henzo(b)fluoranthene (b)
1 44
3
*
0.87
0.091
0.1 5
0.37
7b.
benzo(k)fluoranthene (b)
76.
chrysene
144
3
ND
2.2
0.81
1 .1
1.4
77.
ncrnaphthylene
144
3
ND
0.035
*
NU
0.01 8
78.
anthracene (c)
144
3
*
22 .0
1 1 .0
7.7
13.6
8) .
phcnanthrene (c)
AO.
fluorene
144
3
ND
5.3
1 . 75
1 .8
3.0
84.
pyrene
144
3
*
6 .4
2.9
3.0
4.1
1 14.
antlmony
144
3
<0.(105
<0.005
<0.005
<0.005
<0.005
1 15.
arsenic
144
3
<0.001
<0.001
0.004
<0.001
0.0013
117.
bery1 llum
144
3
<0.000-)
<0.0005
<0.0005
<0.0005
<0.0005
118.
cadmium
1 44
3
<0.001
<0.001
<0.001
<0.001
<0.001
119.
chromium
144
3
0.008
0.010
O.OOfl
0.006
0.008
120.
copper
144
3
0.029
0.016
0.0J5
0.02
0.024
121 .
cyanIde
28
0.002
0.002
144
3
0.14
0.064
0.021
0.007
0.0J1
1 22.
1 end
144
3
0.01
0.0 76
0.5
0.011
0.2
123.
mercury
144
3
0.0002
0.0002
<0.0002
<0.0002
0.0001
1 24.
nickel
144
3
0.012
0.004
0.004
0.015
0.008
\2b.
se1 en 1 urn
144
3
0.2 b
<0.008
<0.008
<0.008
<0.008
1 26.
s 1 lver
144
3
0.0005
<0.001
0.004
<0.0005
<0.001
127.
thai 1lum
144
3
<0.001
<0.001
<0.001
<0.001
<0.001
1 28.
z Inc
144
3
0.02
0.02
0.02
<0.02
0.01
W
H
3
>
~<
>
tr1
c
s
M
25
C
3
in
c
ffl
o
>
H
M
O
O
W
~<
C/)
M
O
H
-------
Table V-2 (Continued)
PRIMARY ALUMINUM SAMPLING DATA
ANODE PASTE PLANT WET AIR POLLUTION CONTROL
RAW WASTEWATER
CTi
Pollutant
Nonconventtonalg
ammonia
chemical oxygen demand (COD)
fluoride
phenols (total; by 4-AAP method)
total organic carbon (TOC)
Conventlonals
oil and greaRe
total suspended solids (TSS)
pH (standard units)
Stream
Code
144
166
166
28
146
166
28
166
164
166
Sample
Typet
Source
0.66
Day 1
Concentrations
0.016
<1.0
5.0
3.8
300
0.58
0.086
NT)
56
25
1,900
36
6.0
Day l
(mfc/U
Day 3
2.7
180
0.3
0.61
16
160
19
6.0
2.0
50
0.36
3.0
15
56
16
Average"
2.8
177
0.6
0.086
1.7
29
25
705
23
(a) No samples were analyzed for aabeatos and the volatile, pesticide, or acid extractable toxic organic pollutants.
(b), (c) Sum of two compunds not separate by method used.
tSample type. Note: These numbers also apply to subsequent sampling data tables in this section.
1 - one-time grab
2 - 26-hour manual compoalte
3 - 26-hour automatic composite
6 - 68-hour manual composite
5 - 68-hour automatic composite
6 - 72-hour manual coftyoalte
1 - 72-hour automatic composite
^Indicates less than or equal to 0.01 mg/1.
^Indicates less than or equal to 0.005 mg/1.
W
M
s
>
>
C
s
M
z
c
s
c/i
c
a
o
>
H
in
o
o
w
K
to
M
o
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - V
TABLE V-3
Plant
Code
354
342
343
364
371
WATER DISCHARGE RATES FOR ANODE BAKE PLANT
WET AIR POLLUTION CONTROL
(1/kkg of Anodes Baked)
Furnace Type
Open top ring
furnace
Tunnel kiln
Closed top
ring furnace
Open top ring
furnace
Open top ring
furnace
Scrubber Type
Spray tower, wet
ESP
Spray tower, dry
Venturi
Spray tower, dry
Wet ESP
Product ion
Normalized
Percent Discharge
Recycle Flow
99 +
0
0
91
720
11300
43235
496
1526
662
-------
Table V-4
PRIMARY ALUMINUM SAMPLING DATA
ANODE RAKE PLANT SCRUBBER LIQUOR
RAW WASTEWATER
o>
o>
Fo 11 ut nm;
Toxic FoI 1ntants(a)
1 . acenapbf.hene
39. fluoranihrne
55. naphthalene
66. b I s(2-ethyIhexyI) phthalnte
68. dl-n-butyl phthalate
69. dl-n-octyl phthalate
7 2. benzo(a)anthracene
7 3. bn>7.o(a) py rene
76. chrysenc
78. flnfhracrne (b)
81. ph^nanthrene (b)
79. benr.o(Rh! )pery!rne
80. fluorrne
82.
50
~<
>
(/)
G
W
O
>
H
W
O
O
50
~<
U)
w
o
H
-------
Table V-4 (Continued)
PRIMARY ALUMINUM SAMPLING DATA
ANODE BAKE PLANT SCRUBBER LIQUOR
RAW WASTEWATER
CTi
K
>
G
2
M
z;
G
2
to
G
CD
O
>
t-3
M
O
O
K
to
tn
n
H
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - V
TABLE V-5
WATER DISCHARGE RATE FOR
ANODE CONTACT COOLING AND BRIQUETTE QUENCHING
(1/kkg of Green Anodes or Briquettes Manufactured)
Production Normalized
Plant Code Recycle Discharge Flow
34 5 *
96
988
349
0
9174
353
NA
NA
354
0
1434
3SS
NA
NA
357
100
0
371
0
1051
359*
0
2711
360*
0
1472
367
97
113
6101
NA
NA
* Briquette Quenching
665
-------
Table V-6
PRIMARY ALUMINUM SAMPLING DATA
PASTE PLANT CONTACT COOLING WATER
RAW WASTEWATER
Pollutant
Toxic Pollutanta(a)
Stream
Code
Sample
Type
Source
Pay 1
Concentration*
Day 2 ~
il/j?
Pay 3
Average"
CT\
Q\
CTv
1 . acenaphthene 137
1 ND
0.04
0.04
39. fluoranthene 137
| •
0.13
0.13
55. nnphthalene 137
i ra>
*
•
66. blfl(2-ethylhexy1) phthalate 137
68. dl-n-butyl phthalate 137
i *
1 ND
0.016
•
0.016
•
72. benzo(a)anthracene 137
1 ND
0.054
0.054
73. benzo(a)pyrene 137
1 ND
0.041
0.041
76. chrynene 137
78. anthracene (b) 137
1 ND
0.08
0.08
] *
0.11
0.11
81. phennnthrene (b)
79. benzo(ghl)perylene 137
1 ND
0.019
0.019
80. fluorene 137
1 ND
•
•
82. dlbenzo(a,h)anthracene 137
83. lndeno(l ,2,3-cd)pyrene 137
1 ND
0.012
0.012
1 ND
0.028
0.028
84. pyrene 137
1 ND
0.15
0.15
114. antimony 137
1
<0.005
<0.005
115. araenlc 137
1 <0.001
<0.001
<0.001
117. berylllua 137
1
<0.0005
<0.0005
118. cadnlum 137
1
<0.001
<0.001
119. chroolua 137
1 0.011
0.01
0.01
120. copper 137
1 0.041
0.18
0.18
121. cyanide 28
137
1
1
0.002
0.003
0.002
0.003
122. lead 137
1 0.17
0.008
0.008
123. mercury 137
1 <0.0002
<0.0002
<0.0002
124. nickel 137
1 <0.005
0.015
0.015
125. aelenlua 137
1
<0.008
<0.008
126. allver 137
1 <0.001
<0.0005
<0.0005
127. thallium 137
1
<0.001
<0.001
128. zinc 137
1 0.04
0.02
0.02
>
(/>
C
CO
O
>
H
M
O
O
»
K
(/>
M
O
H
-------
Tabic V-6 (Continued)
PRIMARY ALUMINUM SAMPLING DATA
PASTE PLAOT COOTACT COOLING WATER
RAW WASTEWATER
a\
a\
Pollutant
Nonconventlonalg
ammonia
chemical oxygen demand (COD)
f luorlde
phenols (total; by 4-AAP method)
total organic carbon
Convent tonal a
oil and grease
total suspended solids (TSS)
pll (standard units)
Stream
Code
137
137
137
28
137
137
28
137
137
137
28
Sample
Type
Source
5.0
Day I
0.41
50
2.6
0.086
0.007
150
25
28
4.0
5.0
7.4
Concent rat lona (n/I)
Da
Day Z
K7T
7.9
Averan«~
0.41
50
2.6
0.086
0.007
150
25
28
4.0
~d
50
M
3
>
50
K
>
r
w
a
a
o
>
1-3
M
O
O
50
K
(a) No samples were analyzed for the volatile, pesticide, or acid extractable toxic organic pollutants.
(b) Reported together.
(/)
w
O
•-3
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - V
TABLE V-7
WATER DISCHARGE RATES FOR CATHODE REPROCESSING
(1/kkg of Cryolite Production)
Plant Code Discharge Flow
369 62050
363 8400
368 31700
370 34540
668
-------
Table V-8
PRIMARY ALUMINUM SAMPLING DATA
CATHODE REPROCESSING
RAW WASTEWATER
CT\
CT\
VO
Pollutant
Toxic Pollutants(a)
I . ncenaphthene
4. benzene
23. chloroform
iy. f luoranthene
!>4. Isophorone
naphthalene
62. N-n1trosodlphenylamlne
66. his(2-ethylhexy1) phthalate
67. butyl benzyl phthalate
68. dl-n-butyl phthalate
70. diethyl phthalate
72. benzo(a)anthracene
73. benzo(a)pyrene
74. benzo(b)fluoranthene (b)
75. benzo(k)fluroanthene (b)
Strean
Code
127
142
127
12/
127
142
142
127
142
142
12/
142
127
142
127
142
127
142
12/
142
127
142
127
142
Sample
Type
Source
U .026
0.02
*
*
ND
*
NO
NO
0.03J
*
*
NO
ND
NO
NO
NO
NO
NO
NO
NO
0.1 y 1
1 Concent rat ions (m^/L)
Ody 2 Day 3
ND
0.016
0.17V
0. 112
ND
*
ND
0.437
o.oa4)
NO
ND
ND
<0.1 1
NO
0.02V
NO
0.0J4)
0. I
NO
NO
NO
NO
NO
NO
0.014
0.01 7
0.021
0.073
NO
NO
NO
NO
0.029
O.OIH
Avera
0.01 6
0.0 2
0.1/9
0.095
0.4 3 7
*
0.UM5
U.0I4
o.oi ^
0. U2 *)
~tl
SJ
H
s
>
SJ
>
tr1
a
3
H
ss
a
s
(/j
a
a
o
>
M
a
o
jo
~<
(A
M
O
-------
Table V-8 (Continued)
PRIMARY ALUMINUM SAMPLING DATA
CATHODE REPROCESSING
RAW WASTEWATER
o\
o
Pollutant
Toxic Pollutanta(a) (Cont.)
76. chryaene
77. acenaphthylene
78. anthracene (c)
81. phenanthrene (c)
79. benzo(ghl)perylene
80. fluorene
82. dtbenzo(a,h)anthracene
83. IndenoO ,2 ,3-cd)pyrene
B4. pyrene
90. dleldrln
91. chlordane
92. 4.4'-DDT
9J. 4,4'-DDE
99. endrln aldehyde
100. hepcachlor
Streaa
Code
127
142
12 7
142
127
142
127
142
127
142
127
142
127
142
127
142
127
127
127
127
127
127
Sanpla
Type
Source
*
M>
M)
0.016
*
ND
M)
ND
ND
Pay 1
ND
<0.11
ND
*
0.098
0.036
ND
ND
ND
*
ND
M>
ND
ND
0.179
0.11
*•
•*
**
ND
*•
• *
Concent ratlona
Day 1 ' 1
Day 3
0.046
*
0.041
ND
*
ND
M)
0.092
0.056
0.029
0.074
Average
0.034
*
0.098
0.35
0.179
0.092
• •
»*
*•
• •
*•
~d
W
H
s
>
Kj
>
tr«
c
s
hi
25
G
3
C/l
G
ro
o
>
H
w
o
o
50
K
c/i
w
o
-------
Table V
-8 (C
ont inued)
PRIMARY ALUMINUM
SAMPLING
DATA
CATHODE
reprocessing
RAW
WASTEWATER
Stream
Sample
Concentratlona
(¦r/i)
Pollutant
Code
Type
Source
Day 1
Day 2
Day 3
Averase
Toxic Pollutanti
i(a) (Cont.)
101. heptachlor
epoxide
127
1
**
**
**
103. beta-BHC
127
1
**
**
**
104. gamma-BHC
127
1
ND
**
**
107. PCB-1254
127
1
**
**
**
110. PCB-1248
127
1
**
**
**
114. antimony
127
142
1
<0.1
<0.005
<0.1
0.1
0.05
0.23
<0.1
0.13
11S. arsenic
127
142
1
<0.01
<0.001
0.61
0.38
0.14
0.15
0.61
0.22
117. berylllun
127
142
1
<0.01
<0.0005
0.4
0.002
0.002
0.02
0.4
0.008
118. cadnlun
127
1
<0.02
<0.001
0.2
<0.001
<0.001
0.05
0.2
0.02
119. chroolua
127
142
1
<0.05
0.008
0.6
0.009
0.008
0.025
0.6
0.014
120. copper
127
142
1
3
0.09
0.029
1.0
1.3
0.83
1.6
1.0
1.2
121. cyanide
127
142
1
0.14
129
100
58
65
129
74
122. lead
127
142
1
3
0.3
0.01
5
0.11
0.1
0.19
5.0
0.13
123. aercury
127
142
1
3
0.0001
0.0002
0.0062
<0.0002
<0.0002
<0.0002
0.0062
<0.0002
-------
Table V-8 (Continued)
PRIMARY ALUMINUM SAMPLING DATA
CATHODE REPROCESSING
RAW WASTEWATER
CTl
-O
M
Pollutant
Toxic Pol lutanf(a) (Cont.)
Streaa
Code
Sample
TyPc
Source
Day 1
Concentratlona
Day 2 ~
¦anganeae
phenola (total; by 4-AAP nethod)
total organic carbon (TOC)
127
127
142
127
142
Day 3
0.3
0.014
4.0
0.008
0.024
2 .030
82
0.18
280
0.6
100
Average
124. nickel
127
142
1
3
0.2
0.012
4.0
0.87
0.59
1.3
4.0
0.92
125. aelenlua
127
142
1
3
0.01
0.2S
0.01
0.7
0.092
44
0.01
14.93
126. allver
127
142
1
3
<0.02
0.005
<0.02
0.06
0.025
0.045
<0.02
0.04
127. thallium
127
142
1
<0.1
<0.001
<0.1
<0.005
<0.001
0.39
<0.1
0.13
128. zinc
Nonconventlona1¦
127
142
1
3
<0.6
0.02
1.0
0.04
0.01
0.06
1.0
0.04
alualnua
127
1
1.0
3,000
3,000
a anion la
calcium
127
142
127
1
1
0.44
<50
115
18
1,300
9.4
10
115.0
12
1,300
chemical oxygen deaand (COD)
127
142
1
3
27,200
200
300
400
27,200
300
fluoride
127
142
1
3
13,000
1,160
790
1,070
13,000
1,007
Iron
127
1
3.0
2,000
2,000
¦agnealua
127
1
5.0
6.0
6.0
4.0
0.008
0.3
2,030
154
W
M
s
>
~<
>
tr1
c;
3
M
2:
c
s
to
c;
tr)
o
>
w
O
O
W
~<
to
ro
o
-------
Table V-8 (Continued)
PRIMARY ALUMINUM SAMPLING DATA
CATHODE REPROCESSING
RAW WASTEWATER
o\
-j
u>
Pollutant
Conventionale
oil and greaae
total suspended solids (TSS)
pH (standard units)
Stream
Code
127
142
127
142
142
Sample
TyPe
Source
<1
Day 1
5
72
54,500
25
11
Concentrations
Day 2 _
Day 3
25
19
11
1,400
130
Average
5
499
54,500
58
(a) No sample was analysed for the acid extractable toxic organic pollutants. The volatile and pesticide fractions
were not analyzed for in stream 142.
(b),(c) Reported together.
Hi
SJ
M
s
>
K
>
a
s
M
!25
a
s
cn
a
m
o
>
M
o
o
»
K
in
M
0
1
<
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - V
TABLE V-9
WATER DISCHARGE RATES FOR POTLINE WET AIR POLLUTION CONTROL
(1/kkg of Aluminum Reduction Production)
Production
Normalized
Plant
Code
Cell
Type
Scrubber Type
Percent
Recycle
Discharge
Flow
363
PB,
HSS
Solid cone spray,
wet scrubber
100
0
369
HSS
Wet ESP
91
592
346
PS
Scrubbers, ESP
0
2047
349
VSS
Venturi followed
by packed section
96
1160
368
HSS
Wet ESP
99 +
1150
370
HHS
Floating bed, wet
scrubbers
99 +
463
348
PB
Multiple cyclones
and floating bed
NR
NR
366
HSS
Wet ESP
NR
NR
NR ~
not reported
674
-------
Table V-10
PRIMARY ALUMINUM SAMPLING DATA
POTLINE WET AIR POLLUTION CONTROL
RAW WASTEWATER
CT\
cn
Pollutant
Toxic Pollutanta(a)
1. acenaphthene
4. benzene
39. fluoranthene
44. methylene chloride
55. naphthalene
65. phenol
66. bls(2 -ethylhexy 1) phthalate
67. butyl benzyl phthalate
68. dl-n-butyl phthalate
72. benzo(a)anthracene
73. benzo(a)pyrene
74. benzo(h)fluoranthene
75. benzo(k)fluoranthene
76. chryaene
Stream
Coda
Sample
T?Pe
145
194
194
145
194
194
145
194
194
145
194
145
194
145
194
145
194
145
194
145 (b)
194
145 (b)
194
145
194
Source
*
ND
ND
*
*
*
ND
ro
*
0.02
ND
ro
to
ND
ND
*
ND
*
*
ND
Day 1
Concentratlona
Day 2
("&/1)
p«y 3
ND
ND
0.088
0.05
2.2
0.32
ND
0.02
0.07
0.02
*
ND
ND
*
ro
0.86
0.18
ND
0.57
0.75
0.26
0.75
0.21
1.4
0.23
0.25
4.1
0.03
0.041
0.012
*
1.9
1.3
1.7
1.7
3.1
0.84
26.0
N>
0.075
N>
0.061
14.0
11.0
11.0
11.0
30.0
Avra«e~
0.39
0.05
10.8
0.32
0.03
0.02
0.07
0.04
*
0.012
0.020
5.6
0.18
6.2
0.57
4.5
0.26
4.5
0.21
11.5
0.23
*1
W
>
tr<
w
c
»
o
>
H
M
O
O
W
~<
(/)
W
O
H
-------
Table V-10 (Continued)
PRIMARY ALUMINUM SAMPLING DATA
POTLINE WET AIR POLLUTION CONTROL
RAW WASTEWATER
as
-j
a\
13
Sc ream
Sample
Concent rat Ions
JO
> ¦
Pollutant
Code
Type
Source
Uay \
0«y 2
"ay
Average
r~"1
Toxic Pal lutants (a) (Cont.)
#¦25
>
7 7. acenaphthylene
3
NI>
*
*
NO
*
*<
194
4
Nl)
*
*
>
[-<
78. anthracene (c)
145
1
*
0.092
0.34
3.1
1.2
G
2
81. phenanthrene !¦>
80. fluorene
14b
3
ND
i
0.039
0.24
0.093
c/i
c
194
4
Nl)
0.U5
0.05
00
o
82. diben2«(a,h)Hnthracene
145
3
ND
ND
0.096
3.1
1 .6
>
194
4
ND
0.1 1
0.11
w
83. tnduno(1,2,3-cd)pyrene
145
3
ND
ND
0.290
1 .900
1 .10
o
194
4
ND
0.35U
0.350
o
»
84. pyrene
145
3
•
2.3
4.3
27.0
1 1
K
194
4
•
0.22
0.22
86. toluene
194
4
•
•
»
M
114, anllmony
145
j
1 ,5
0.05
O.HH
0.8
M
194
4
0 .CD
0.45
0.45
O
t-3
115. arsenic
145
3
-------
Table V-10 (Continued)
PRIMARY ALUMINUM SAMPLINC DATA
POTLINE WET AIR POLLUTION CONTROL
RAW WASTEWATER
Streaa
ON
Pollutant
Code
Type
Source
Day 1
Day 2
Day 3
Average
Toxic Pollutanta(a) (Cont.)
120. copper
145
194
3
4
0.029
0.0055
0.096
0.026
0.11
0.11
0.11
0.026
121. cyanide
145
194
3
4
0.14
<0.004
180
<0.004
180
150
170
<0.004
122. lead
145
194
3
4
0.01
<0.022
0.42
<0.022
0.46
0.49
0.46
<0.022
123. aercury
145
194
3
4
0.0002
<0.002
<0.0002
<0.004
<0.0002
<0.0002
<0.0002
<0.004
124. nickel
145
194
3
4
0.012
0.042
0.31
3.9
0.37
0.47
0.38
3.9
125. aelenluo
145
194
3
4
0.25
<0.001
1.8
<0.002
1
0.75
1.2
<0.002
126. allver
145
194
3
4
o.ooos
<0.002
0. 36
<0.004
0.23
0.21
0.27
<0.004
127. thalllun
145
194
3
4
<0.001
<0.05
0.62
<0.09
0.66
0.69
0.66
<0.09
128. zinc
145
194
3
4
0.02
0.032
0.09
0.065
0.1
0.1
0.1
0.065
Nonconventlonala
aamonla
145
1
0.44
14.0
8.8
5.9
9.6
chemical oxygen denand (COD)
145
3
1,200
1,300
2,100
1,533
fluoride
145
1
610
990
400
700
phenola (total; by 4-AAP aethod)
145
194
1
4
0.014
<0.005
0.5
0.725
0.45
0.13
0.4
0.725
total organic carbon (TOC)
145
3
1,800
1,300
1,800
1,600
>
w
G
ro
o
>
t-3
w
Q
O
»
K
(/)
W
0
t-3
1
<
-------
Table V-10 (Continued)
PRIMARY ALUMINUM SAMPLINC DATA
POTLINE WET AIR POLLUTION CONTROL
RAW WASTEWATER
oo
Pollutant
Conventlonala
oil and greaae
total suspended solids (TSS)
pH (atandard units)
Strean
Code
IAS
145
145
Sanpla
Type
Source
<1
Day 1
11.0
320
10
Concentrations (mn/1)
" Dat 3
bay ?
Ba*
5.9
310
10
260.0
2,800
Average"
92
1.100
(a) Streaa 145: No aabestoa, volatile, acid extractable, or peatlclde organic pollutant aaaples were analyzed.
Streaa 194: No peatlclde fraction waa analyzed.
No asbestoa aaaple waa analyzed.
(b),(c) Reported together.
~0
M
3
>
~<
>
f
c
s
M
Z
G
3
CO
G
O)
O
>
H
W
O
O
»
~<
cn
w
o
H
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - V
TABLE V-ll
WATER DISCHARGE RATES FOR POTLINE S02 WET AIR POLLUTION CONTROL
(1/kkg of Aluminum Reduced)
Plant Code Percent Recycle Discharge Flow
359 77 1430
360 75 1500
679
-------
Plan
Code
353
354
364
349
360
359
361
351
PRIMARY ALUMINUM SUBCATEGORY SECT - V
TABLE V-12
DISCHARGE RATES FOR POTROOM WET AIR POLLUTION CONTROL
(1/kkg of Aluminum Reduction Production)
Product ion
Normali zed
Cell Percent Discharge
Type Scrubber Type Recycle Flow
PB 104 low pressure 42 1593
wet scrubber
PB Low pressure spray 98 568
type
PB Cross flow packed 98 2790
bed wet scrubber
VSS Low energy foam 99 70
scrubber
VSS Low pressure sprays 90 25024
VSS Low pressure sprays 93 1685
PB NR NR NR
PB Water spray wet 0 169000
680
-------
Table V-13
PRIMARY ALUMINUM SAMPLING DATA
POTROOM WET AIR POLLUTION CONTROL
RAW WASTEWATER
00
Pollutant
Tonic Pollutanta(a)
1. acenaphthene
4. benrene
2 3. chlorofora
39. fluoranthene
44. Methylene chloride
34. lsophorone
55. naphthalene
66. bla(2-ethylhexyl) phthalate
67. butyl benzyl phthalate
68. dl-n-buty1 phthalate
72. benzo(a)anthracene
73. benzo(a)pyrene
76. chryaene
Streaa
Code
26
195
26
195
26
195
26
195
26
195
26
195
26
195
26
195
26
195
26
195
26
195
26
195
26
195
Sanple
Type
Source
HD
Pay 1
H)
ND
ND
ND
0.02
ND
ND
M>
ND
*
*
ND
0.023
ND
ND
0.11
0.055
ND
*
ND
*
ND
0.13
0.03
0.068
ND
0.126
ND
ND
0.04
ND
0.04
ND
0.03
¦Concentratlona
Day 2 ~
in/j)
H>
ND
0.011
M>
ND
H)
ND
H)
Average
*
*
0.023
0.11
0.055
0.071
0.03
0.068
0.126
0.04
0.04
0.03
>
r
G
3
M
25
C
3
W
G
m
o
>
M
O
O
»
~<
w
M
o
-------
Table V-13 (Continued)
PRIMARY ALUMINUM SAMPLING DATA
POTROOM WET AIR POLLUTION CONTROL
RAW WASTEWATER
CT\
00
NJ
Pollutant
To»lc Pollutanta(a) (Cont.)
78. anthracene
79. benzo(ghl)perylene
83. lndeno(l,2,3-cd)pyrene
84. pyrene
86. toluene
87. trlchloroethylene
89. aldrin
90. dieldrln
92. 4,4'-DDT
93. 4,4'-DDE
94. 4,4'-DDD
95. alpha-endosulfan
96. beta-endosulfan
97. endoaulfan aulfate
98. endrln
99. endrln aldehyde
100. heptachlor
101. heptachlor epoxide
102. alpha-BHC
103. beta-BHC
104. ganma-BHC
105. delta-BHC
(b)
(b)
(b)
(b)
18
!8
81
(b)
(b)
(b)
(b)
(b)
(b)
Streaa
Code
26
195
26
195
26
195
26
195
26
195
26
195
26
Sample
Type Source
Day 1
Concentratlone
Day 2
Day 3
N>
ND
re
ND
0.01
ND
0.01
ND
*
ND
0.05
*
W>
*
N>
N>
ND
N>
ND
Average"
0.01
0.01
0.05
*
H
s
§
K
>
tr"
G
3
M
55
G
3
M
G
tfl
O
>
H
ra
o
o
K
C/l
M
O
H
91. chlordane
26
-------
Table V-13 (Continued)
PRIMARY ALUMINUM SAMPLING DATA
POTROOM WET AIR POLLUTION CONTROL
RAW WASTEWATER
Pollutant
Toxic Pollutante(a) (Cont.)
CTi
00
U>
106. PCB-1242
107. PCB-1254
108. PCB-1221
109. PCB-12J2
110. PCB-1248
111. PCB-1260
112. PCB-1016
113. toxaphene
114. antimony
115. araenlc
116. aabeatoa (HFL)
117. beryl 1lua
118. cadnlum
119. chronlua
120. copper
121. cyanide
122. lead
123. aercury
(O
(c)
(c)
TJ
so
M
3
>
so
>
t"1
C
s
M
:z
c
s
C/)
C
03
n
>
i-3
M
o
o
so
C/)
m
n
t-3
-------
Table V-13 (Continued)
PRIMARY ALUMI MUM SAMPLING DATA
POTROOM WET AIR POLLUTION CONTROL
RAW WASTEWATER
Stream Sample Concentrations (mg/1)
Pollutant Code Type Source Day I Day 2 Day 3 Average
Toxic Po1lutants(a) (Cont.)
12*. nickel 26 3 (e) <0.5 <0.5 <0.5
195 4 0.042 O.U39 0.039
125. selenium 26 3 (e) 0.6 0.J5 0.5
195 4 <0.001 <0.001 <0.001
126. silver 26 3 (e) <0.25 <0.25 <0.25
195 4 <0.002 <0.002 <0.002
127. thallium 26 3 (e) <0.05 <0.05 <0.05
195 4 <0.05 <0.001 <0.001
128. zinc 26 3 (e) 0.46 0.38 0.42
00
195 4 0.032 0.055 0.055
Nonconvent tonal8
aluminum 26 3 (e) 200 200 200
calcium 26 3 (e) 36 24 30
chemical oxygen demand (COD) 26 1 225 J59 '*48 344
fluoride 26 1 150 150 280 193
Iron 26 3
-------
Table V-13 (Continued)
PRIMARY ALUMINUM SAMPLING DATA
POTROOM WET AIR POLLUTION CONTROL
RAW WASTEWATER
CTi
00
<_n
Conventlonala
Stream Sample _ Concentratlona (br/1)
Pollutant Code Type Source Day 1 Day 2 Day 3 Average
3
>
oil and greaae 26 1 5 2 3 3.3 ^
total suapended aollda (TSS) 26 1 2,660 1,983 2,355 2,333 >
IT1
pH (atandard unlta) 26 1 10.0 9.4 9.15 G
2C
M
25
c;
s
to
c;
to
o
>
H
(a) Stream 195 was not analysed for the peatlclde fraction, acid fraction of organic toxic pollutants, or asbestos. M
Three sanplea froa stress 26 were analyzed for the acid fraction toxic pollutants; none waa detected. O
(b),(c),(d) Reported together. O
(e) Hetala sanples for Day 1 were analyzed; however, the large variation of this data froa Days 2 and 3 Bade It
auspect, so It was not used In developing these regulatlona
(HFL) - Million flbera per liter.
to
M
O
H
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - V
TABLE V-14
WATER DISCHARGE RATES FOR DEGASSING WET AIR POLLUTION CONTROL
((1/kkg of Aluminum Refined and Degassed)
Production
Normalized
Plant Percent Discharge
Code
Scrubber Type
Recycle
Flow
354
Ventur i
0
2840
369
Packed Tower
0
1060
359
ESP
0
3130
361*
NR
NR
NR
~Data reported with potline and potroom scrubbing and cannot be
separated.
NR -- Not reported
6B6
-------
Table V-15
PRIMARY ALUMINUM SAMPLING DATA
REFINING AND DEGASSING WET AIR POLLUTION CONTROL
RAW WASTEWATER
Pollutant
Toxic Pollutanta(a)
114. ant loony
115. arsenic
117. beryllium
118. cadalun
119. chromium
120. copper
121. cyanide
122. lead
123. aercury
124. nickel
125. aelenlun
126. allver
127. thalllua
128. sine
Nonconventlona1¦
Stream
Code
ISO
150
150
ISO
150
150
150
ISO
ISO
150
ISO
150
ISO
150
Sample
Typc
Source
Pay I
<0.01
<0.0005
0.0076
0.0001
<0.002
<0.004
0.01
0.14
<0.01
0.0019
0.014
0.0005
<0.002
<0.0005
0.02
Concent ratlona (ag/1)
bay ? bay 3
Averane
<0.0005
0.0076
0.0001
<0.002
<0.004
0.01
0.14
<0.01
0.0019
0.014
0.0005
<0.002
<0.0005
0.02
phenola (total; by 4-AAP aethod)
150
<0.001
<0.001
<0.001
(a) Thla aaaple waa not analyzed for any toxic organic pollutanta, and only phenola of the nonconventlonal and
conventional pollutanta.
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - V
TABLE V-16
WATER DISCHARGE RATES FOR
POT REPAIR & POT SOAKING
(1/kkg of Aluminum Reduction Production)
Production Normalized
Plant Code
Percent Recycle
Discharge
349
NA
146
355
0
10984
356
100
0
357
100
0
358
0
1044
364
NR
130
365
NR
100
366
NR
3
369
NR
730
6101
100
0
686
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - V
TABLE V-17
WATER DISCHARGE RATES FOR
POT REPAIR & POT SOAKING
(1/kkg of Aluminum Reduction Production)
Production Normalized
Plant Code Percent Recycle Discharge Flow
362 99+ 123
355 99 459
350 98 1801
340 98 9549
353 94 3303
345 82 2610
357 48 600
352 20 19473
371 0 6964
369 0 12552
349 0 15638
351 0 23477
348 0 27188
365 0 32860
347 0 34903
360 0 38406
367 0' 45870
359 0 57129
343 0 59214
370 0 79230
342 93 NA
361 NA NA
343 NA NA
366 0 NA
346 NA NA
6101 NA NA
689
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - V
TABLE V-18
WATER DISCHARGE RATES FOR
DIRECT CHILL CASTING CONTACT COOLING
(ALUMINUM FORMING CATEGORY)
(1/kkg of Aluminum Cast)
Production Normalized
Plant Code Percent Recycle Discharge Flow
1
100
0
2
100
0
3
50
0
4
97
0
5
100
0
6
100
0
7
100
0
8
100
0
9
100
0
10
99
0,2989
11
99
0.3252
12
100
0.4169
13
99
0.4169
14
0
120.9
15
98
150.1
16
97
250.2
17
99
313.4
18
0
392.8
19
NR
496.2
20
NR
514.5
21
97
612.9
22
98
629.6
23
0
*7 "7
24
93
963^1
25
94
1113
26
97
1167
27
99
1483
28
96
1534
29
96
1955
30
94
2397
31
92
2753
32
0
3 0 0 2
33
NR
4003
690
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - V
TABLE V-18 (Continued)
WATER DISCHARGE RATES FOR
POT REPAIR & POT SOAKING
(1/kkg of Aluminum Reduction Production)
Production Normalized
Plant Code Percent Recycle Discharge Flow
34 0 5041
35 NR 5337
36 0 9089
37 0 9506
38 0 16590
39 0 29390
40 0 35500
41 0 52540
42 0 58370
43 0 91310
45 98 NR
46 96 NR
47 NR NR
48 0 NR
49 0 NR
50 NR NR
51 0 NR
52 NR NR
53 0 NR
54 NR NR
55 NR NR
56 100 NR
56 NR NR
58 NR NR
59 0 NR
60 90 NR
61 NR NR
691
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - V
TABLE V-19
WATER DISCHARGE RATES FOR
CONTINUOUS ROD CASTING CONTACT COOLING
(1/kkg of Aluminum Reduction Production)
Production Normalized
Plant Code Percent Recycle Discharge Flow
346 NR NR
355 99 415
362 99+ 11.3
nr — Not Reported
i
692
-------
Table V-20
PRIMARY ALUMINUM SAMPLING DATA
CASTING CONTACT COOLING WATER
RAW WASTEWATER
Streaa Sample Concentrations (mr/1)
Pollutant Code Type Source Day 1 Dpy 2 Day 3 Avtraw
Toxic Pollutanta(a)
4. benzene
126
0.026
0.013
0.013
23. chloroforo
126
0.02
•
66. bls(2-ethylhery1) phthalate
126
0.033
0.117
0.117
67. butyl benzyl phthalate
126
•
0.076
0.076
7 7. acenaphthylene
126
ND
*
*
78. anthracene (b)
81. phcnanthrene (b)
126
*
*
•
84. pyrene
126
•
*
•
91. chlordane
126
**
**
**
92. 4,4'-DDT
126
**
**
**
99. enrfrin aldehyde
126
**
*•
**
102. alpha-BHC
126
**
**
*•
104. gama-BHC
126
**
**
**
107. PCB-1254
126
**
0.00526
0.00526
110. PCB-1248
126
•*
**
**
114. ant loony
126
<0.1
<0.1
<0.1
115. arsenic
126
<0.01
<0.01
<0.01
117. berylllun
126
<0.01
<0.001
<0.001
lt8.' cddolua
126
<0.02
<0.002
<0.002
119. chronlun
126
<0.05
0.01
0.01
120. copper
126
0.09
0.02
0.02
121. cyanide
126
1.38
1.38
122. load
126
0.3
<0.02
<0.02
124. nickel
126
0.2
<0.005
<0.005
-------
Table V-20 (Continued)
PRIMARY ALUMINUM SAMPLING DATA
CASTING CONTACT COOLING WATER
RAW WASTEWATER
CTl
vo
St ream
Pollutant Code
Toxic Pollufants(a) (Cont.)
125. .se 1 en 1 inn \ 26
126. s1 Ive r 126
12 7. tha111um 126
128. zInc 126
None on vent Ion a 1_9
a lum1num 116
calcium 126
chemical oxygen demand (COD) 126
L ron 126
map^nes I um 126
manganese 126
phenols (total; by 4-AAP method) 12b
total organic r;trlmn (TOC) 126
Convent 1onfl1 a
o 1 1 rimt gre;i.se 126
total suspended solids (TSS) 12b
pH (standard units) 126
Sample
TyP1,
Sour re
<0.01
<0.02
<0.1
<0.h
I .0
OU
3.0
i.O
0.1
8.7
Pay I
<0.01
<0.02
<0.1
<0.06
0.3
UU.O
1 .0
10.0
0.1
0 .1 <• 3
20
it
Ub
7.2
Concenr rut tona (idr/1)
Pay ? Day 3~
Aver HRe
<0.01
<0.02
<0.1
<0.0b
0.3
V, .0
W*. 0
1 .0
10.0
0.1
0.143
20
4
V.
W
M
3
>
W
K
>
f
G
2
w
55
G
3
(/)
G
DO
n
>
M
O
O
W
K
C/l
M
n
(a) Mo acM traction organic pollutants were analyzed.
(b) Reported together .
-------
Table V-21
PRIMARY ALUMINUM SAMPLING DATA
CTl
VO
Ln
MISCELLANEOUS
WASTEWATER
r.t re.im
Sample
Concent rat Ions
except as
not ed)
Pol lutant(a)
Code
Typ.e..._
Source
Day 1
Day" 2
Day 3
Averjgt
Tox 1 c
Po 11 u t
t"1
to
C
00
o
>
t-3
W
O
O
w
~<
to
M
O
-------
Table V-21 (Continued)
PRIMARY ALUMINUM SAMPLING DATA
MISCELLANEOUS WASTEWATER
Pollutant(a)
Toxic Pollutants (Cont.)
St ream
Code
Sample
Type
Source
Concent rat Ions (ihr/1 except as noted)
Day I Day ~2 Day 3 Average
w
K
>
tr1
C
3
M
c:
3
(/)
C
ffl
n
>
H
cn
cn
o
»
w
cn
o
H
-------
Table V-21 (Continued)
PRIMARY ALUMINUM SAMPLING DATA
MISCELLANEOUS WASTEWATER
CT\
KD
•vj
St ream
Sample
Concent rations
(mjj/1, e
xcept as
noted)
Po I lutant(a)
Code
type . _
Source
Da> 1
""Day_l2
Day "3 ~
Average
Tox I c
Pollutants (Cont.)
80.
f luorene
124
7
NO
ND
t 40
2
NO
ND
ND
0. 051
0. 051
143
3
ND
ND
ND
*
*
192
2
ND
*
*
82.
dlbenzo(a,h)anthracene
124
7
ND
ND
140
2
ND
ND
ND
0. 34
0. 34
143
3
ND
0. 05
ND
0.04 7
0.049
192
2
ND
ND
83.
lndcno(1,2,3-cd)pyrene
124
7
ND
ND
140
2
ND
0. 87
ND
1. 80
1.3
143
3
ND
0.086
ND
0. 067
0.077
192
2
ND
*
*
84.
pyrene
124
7
*
*
*
140
2
*
5. 3
1 . 7
14
7. 0
143
3
*
0. 065
0. 073
1.6
0. 58
192
2
*
0.04
0. 04
114.
ant linony
124
7
<0. 1
<0. 1
<0. 1
140
2
<0.005
0. 53
2
1.3
1.3
143
3
<0.005
0. 1
0.05
0. 04
0.06
149
1
0.0005
0.0005
0. 0005
0.0002
192
2
0. 024
0.024
0.024
1 1 5.
arsenic
124
7
<0.01
0.05
0.05
140
2
<0.001
2. 3
1.8
0. 62
1.6
143
3
<0.001
0. 3
0. 19
0. 3
0. 3
149
1
0.023
0.01 5
0.019
0.019
192
2
<0.01
<0.01
<0.01
t 1 7.
bery111 urn
124
7
<0.01
0. 08
0.08
140
2
<0.0005
0.03
0.03
0. 05
0.04
143
3
<0.0005
<0.0005
0.002
0.014
0.005
149
1
0.003
0.0006
0. 001
0. 002
192
2
<0.001
<0. 001
<0.001
118.
cadmlum
124
7
<0.02
0. 1
0. 1
140
2
<0.001
0.09
0. 08
0.09
0. 09
143
3
<0.001
0.03
<0.001
<0.001
0.01
149
1
0.007
<0.002
<0.002
<0.004
192
2
0.001
0. 005
0.005
»
M
3
>
~<
>
tr1
C
2
M
z
c
3
U1
c
W
o
>
H
M
O
O
»
~<
C/>
M
O
H
-------
Table V-21 (Continued)
PRIMARY ALUMINUM SAMPLING DATA
MISCELLANEOUS WASTEWATER
CTi
00
St ream
Sample
ConcentratIons
except as
noted)
Pol lutant(a)
Code
IZP_e
Source
Day 1
Day 2
Day 3
Average
Tox Ic
Pollutants (Cont.)
119.
chromium
124
7
<0.05
0.2
0.2
140
2
0.008
0.006
0.01
0.022
0.01
143
3
0.008
0.006
0.016
0.023
0.02
149
1
0.02
<0.004
0.004
0.009
192
<0.004
<0.004
<0.004
120.
copper
124
7
0.09
0.2
0.02
140
2
0.029
0.09
0.09
0.1 1
0.1
143
3
0.029
1 .3
0.35
1
0.9
1 49
1
0.062
0.032
0.046
0.047
192
2
0.005
0.008
0.008
121.
cyan Irle
124
7
98.6
128
127
1 1 8
140
0.14
180
1 70
160
1 70
143
3
0.14
26
36
68
43
149
1
<0.01
54
54
192
<0.004
<0.004
<0.004
122.
1 pad
124
7
0.3
3
3
140
2
0.01
0.32
0.36
0.6
0.4
143
3
0.01
0.01
0.3
0.13
0. 1
149
1
0.02
0.014
0.01
0.01
192
<0.022
0.05
0.05
123.
mercury
1 24
7
0.0001
0.0001
0.0001
140
0.0002
0.0004
<0.0002
<0.0002
0.0001
143
3
0.0002
0.0003
0.0004
0.0003
0.0003
1 49
1
0.003
0.001
0.0007
0.001
192
2
<0.002
<0.002
<0.002
124.
nickel
1 24
7
0.2
1
1
140
2
0.012
0.32
0.37
0.55
0.41
143
3
0.012
0.49
0.26
0.47
0.41
1 49
0.05
0.03
0.04
0.04
192
2
0.008
<0.005
<0.005
12 5.
solenium
1 24
7
<0.01
0.01
0.01
140
2
0.25
1 .2
1
1.3
1 .2
143
3
0.2 5
40
0.05
0.044
1 3
1 ',9
1
0.002
0.001
0.001
0.002
1 92
2
<0.001
•-3
M
O
O
~<
w
w
o
H3
-------
Table V-21 (Continued)
PRIMARY ALUMINUM SAMPLING DATA
MISCELLANEOUS WASTEWATER
o\
vo
vo
Pol lutant(a)
Toxic Pollutants (Cont.)
12 6. si Ivor
12 7. tha 111 urn
128. zinc
Noncon vent 1 ona_l Pollutants
a lumlnum
ammonia
chemical oxygen demand (COD)
f luorlde
phenols (total; by 4-AAP method)
St ream
Code
12/.
160
143
149
192
12/.
I/.0
I /. 3
149
192
124
140
143
149
192
124
124
140
143
149
124
1 AO
1 A3
149
124
140
143
149
I 24
140
143
149
192
Sample
TXP_e ...
Concentrations (rag/l, except as noted)
Source Day f Day_T Day 3 Average
<0.02
0.0005
0.0005
<0.002
<0. 1
<0.001
<0.001
<0.05
<0.6
0.02
0. 02
0.032
0.44
0. 44
0.04
0. 5
0.077
<0.002
<0.002
<0. 1
0.63
<0.005
<0.0005
<0.001
<0.6
0.09
0. 03
0.092
0.04
1,000
38
5.6
3.4
ND
813 '
920
400
950
550
830
0.014
0. 014
<0.001
<0.005
0.035
0.40
0.009
0.01
102
0. 38
0.02
<0.002
0.6
<0.001
<0.0005
0.08
0. 02
0. 036
51
9.8
9.8
ND
1. 400
220
18
830
200
8
0.031
0.27
0. 21
<0.001
0. 3
0.098
<0.002
0. 73
<0.005
<0.0005
0. I 1
0.03
0.056
53
6.3
11
ND
500
300
15
570
420
0.01 5
0. 55
0.088
0. 04
0. 04
0.07
<0.002
<0.002
<0. I
0. 7
<0.004
<0.0005
<0.001
<0. 6
0. 09
0. 03
0. 061
0.04
1.000
47
7. 2
8. 1
813
940
300
16. 5
950
650
480
8
0. 027
0. 41
0. 10
0. 005
102
V
M
3
>
*<
>
f
C
3
Ui
G
W
o
>
i-3
m
-------
Table V-21 (Continued)
PRIMARY ALUMINUM SAMPLING DATA
MISCELLANEOUS WASTEWATER
-j
o
o
Pollutanl(a)
NonconventLonal Pollutants (Cont.)
total organic carbon (TOO
Conventional Pollutants
oil and grease
total suspended solids (TSS)
pH (standard units)
S t ream
Code
124
140
143
Sample
Type
Concentrations (mg/1, except as noted)
Source Day I Day 2 Day 3 Average
1 32
430
160
1 .000
1 30
2,000
110
132
1 .1 00
1 30
12'»
1
3
2
1
140
2
<1
3.6
5.5
9,600
3,200
143
1
<1
<1
1 3
15,000
5,000
124
7
251
251
140
2
620
460
3. 200
1 ,400
143
3
260
27
130
140
149
1
36
19
50
35
124
1
8.7
12
13
12.3
140
1
5
10
1 1
143
1
5
10
10
149
1
8.4
8.5
M
s
>
>
It"
C
3
H
52
C
s
to
C
a
n
>
H
m
CD
o
~<
(a) No samples were analyzed for the acid extractable toxic organic pollutants. Four samples from two streams were
analyzed for the pesticide fraction; none was reported present above its analytical quantification level.
V)
m
n
H
(b),(c) Reported together.
-------
Table V-22
PRIMARY ALUMINUM SAMPLING DATA
TREATMENT PLANT SAMPLES - PLANT A
o
Pollutant
Toxic Po1lutants(a)
tftreaa
Code
Sample
Typg
Source
Pay T
Concentrations (as/1)
Day 2 Day 3
erage
1.
acenaphthene
193
4
ND
0.010
0.010
39.
fluoranthene
193
4
*
0.080
0.080
44.
methylene chloride
193
4
*
ND
66.
hln(2-ethylhexyl) phthalate
193
4
0.020
0.010
0.010
72.
benzo(a)anthracene
193
4
*
*
*
73.
benzo(a)pyrene
193
4
*
0.010
0.010
75.
benzo(k)fluoranthene
193
4
*
*
*
76.
chryacne
193
4
ND
*
*
77.
acenaphthylene
193
4
ND
*
*
78.
anthracene
193
4
A
•
•
79.
benzo(ghl) pyrylene
193
4
ND
*
*
80.
fluorene
193
4
Ml
*
•
83.
lndeno(l,2,3-cd) pyrene
193
4
ND
*
*
0.040
84.
pyrene
193
4
*
0.040
86.
toluene
193
4
*
ND
114.
antlmony
193
4
0.030
0.040
0.040
in.
arnenlc
193
4
<0.010
<0.010
<0.010
117.
berylllun
193
4
<0.001
<0.001
<0.001
118.
cadmium
193
4
0.0018
0.0066
0.0066
119.
chromium
193
4
<0.004
<0.004
<0.004
120.
copper
193
4
0.0066
0.0061
0.0061
121.
cyanide
193
4
<0.004
<0.004
<0.004
122.
lead
193
4
<0.022
0.059
0.059
123.
mercury
193
4
<0.002
<0.002
<0.002
124.
nickel
193
4
0.042
0.120
0.005
125.
selenium
193
4
<0.001
<0.001
<0.001
126.
s11ve r
193
4
<0.002
<0.002
<0.002
127.
thaillum
193
4
<0.050
<0.001
<0.001
128.
Elnc
193
4
0.032
0.058
0.058
Nonconvent tonal
phenols (total; by 4-AAP method)
193
4
<0.005
0.116
0.116
W
M
s
>
w
K
>
It1
C
2
M
z
c
s
w
c
w
o
>
m
o
o
w
K
W
m
n
(a) Stream 193 vas not analyzed for the pesticide fraction organic toxic pollutants.
-------
Table V-23
PRIMARY ALUMINUM SAMPLING DATA
TREATMENT PLANT SAMPLES - PLANT B
o
NJ
St renin
Samp 1e
Concent rat Ions
(mft/1)
Po 1 1 lit ant
Code
Type
Source
Day 1
Day 7
Day 3
Average
To* 1 c
Pol lutant
1 .
accnaphthene
125
7
*
*
ND
Nl)
*
U .
ht'nr.rnt1
125
7
0.026
NO
0.044
ND
0.044
23.
ch Loroform
125
7
0.020
*
0.014
*
0.004 7
39.
fluoranthene
125
7
•
*
NO
ND
*
i>'i.
methylene chloride
12S
7
Nl)
*
NO
NO
*
66.
bls(2-ethy1hexy1) phrhalate
125
0.033
0.069
0.069
67.
butyl benzyl phrhalate
125
/
*
ND
68.
dl-n-butyl phlhalate
125
7
NO
0.032
0.0 32
70.
dimethyl phchalate
125
7
*
*
*
7 7.
accnaphchy1pnp
125
7
Nl)
*
*
78.
inttiraccnc (a)
1 2 5
7
n.oih
0.027
0.02 7
81 .
phenanthrene (a)
*
8(1.
t luorene
12 5
7
NO
*
*
8'i.
py r ene
125
7
*
*
*
90.
d1eIdr1n
125
7
* *
ND
91 .
ch 1 ordane
125
7
* *
» «
* *
92.
.W -OUT
125
7
* *
* *
* »
93.
U . /.' - DDF.
125
/
* *
* *
* *
99.
endrln aldehyde
125
7
* *
Nl)
100.
hept iicli 1 or
125
7
* *
* *
* *
101 .
hcplachlor epoxide
125
7
* *
* *
* *
1113.
heta-IMtC
125
/
* *
* *
* *
1114.
p.anima-HlIC
125
7
Nl)
* *
* *
in/.
PC8-1 254
125
7
* *
* *
* *
110.
PC8-1V.8
125
/
* *
* *
* *
1 u.
antImony
125
7
<0.100
<0.100
<0.100
11 •>.
arsenic
12 5
7
<0.010
<0.010
<0.010
117.
hei y 1 11 um
125
7
<0.010
<0.001
<0.001
118.
cadini um
12 5
/
<0 .0 2
0 .00 3
0.003
119.
ch r omt um
125
7
<0 .05
0 .008
0.008
120.
coppe r
125
7
0 .09
0.1
0.1
121 .
cyanide
125
7
10.10
4.9/
7.46
7.51
122.
1 pad
12 5
/
0 . 300
0 .040
0.040
1 2'..
nickel
1 2 5
7
0.200
0.0/40
0.040
1 2 5.
se1 en 1um
125
7
<0.01
<0.01
<0.01
126.
a 11ver
125
7
<0.0 20
<0 .020
<0.020
127.
1 ha 111um
12 5
7
<0.100
<0.100
<0.100
128.
7.1 nc
125
7
<0 .600
<0.060
<0.060
~d
W
W
K
>
a
s
M
55
C
s
V)
a
a
o
>
M
Q
O
W
K
(/i
M
O
-------
Table V-23 (Cont inued)
o
LiJ
PRIMARY ALUMINUM SAMPLING DATA
TREATMENT PLANT SAMPLES - PLANT B
Stream Sample Concentrations (¦&/!)
Pollutant Code Type Source Day 1 Day 2 Day 3 Average
Nonconventlona1 5®
M
aluminum 125 7 1 20 20 2
aremon1a
12 5 7 1 8. 1 16 14 12 £
calcium 125 7 <50 170 170
chenlcal oxygen demand (COD) 125 7 18
oil fc greaae 125 1 <1 7 4
total auapended sollda (TSS) 125 7 218 218
pll (atandard unlta) 125 1 8.7 11.5 6.3 8.2
fluoride 125 7 68 68
mngnpslum 125 7 5 12 12 fi
phenola (total; by 6-AAP Method) 125 1 0.004 0.007 0.008 0.006 CZ
total organic carbon (TOC) 125 7 16 16 3
H
Conventional Z
W
G
ffl
n
>
w
CI
o
30
~<
W
W
n
(a) Reported together
-------
Table V-24
PRIMARY ALUMINUM SAMPLING DATA
TREATMENT PLANT SAMPLES - PLANT C
-j
o
PollutanC
Stream
Code
Sanple
Type
Source
Day 1
ConcentratIons
Day 2
(or/1)
Day 3
Average
Toxic
Pollutants
1.
acenphthene
93
3
ND
0.010
0.012
0.013
0.012
4.
benzene
93
1
*
ND
*
*
*
23.
chloroforn
93
1
*
*
*
o.ou
*
28.
3,3 'dlchlorobenzldlne
93
3
*
W)
ND
ND
15.
2 ,4-dlnltrotoluene (a)
93
3
ND
ND
*
*
*
36.
2,6 dlnltrotoluene (a)
19.
fluornnthene
93
3
*
0.034
0.011
0.013
0.019
55.
naphthalene
93
3
ND
ND
ND
*
*
66.
bla(2-ethylhexyl) phthalate
93
3
o.ou
*
0.010
*
0.003
67.
butyl benzyl phthalate
93
3
*
*
*
*
68.
dl-n-butyl phthalate
93
3
0.031
*
0.024
0.025
0.016
69.
dl-n-octyl phthalate
93
3
ND
0.013
*
W>
0.007
70.
diethyl phthalate
93
3
ND
ND
*
ND
*
71.
dimethyl phthalate
93
3
ND
ND
*
*
*
73.
benzo(a) pyrene
93
3
ND
*
*
*
*
74.
benzo(b) fluoranthene
93
3
fffl
W)
*
ND
*
75.
benzo(k) fluroanthene
93
3
ND
ND
*
ND
*
76.
chrysene
93
3
*
*
*
*
78.
anthracene (b)
93
3
*
ND
*
*
*
81.
phenanthrene (b)
79.
benzo(ghl) perylene
93
1
ND
*
ND
ND
*
80.
fluorene
93
3
W)
*
ND
*
*
82.
dlbenzo (a,h) anthracene
93
3
ND
*
ND
ND
*
83.
lndeno (l,2,3-c,d) pyrene
93
3
*
*
ND
M)
*
84.
pyrene
93
3
*
0.032
*
0.010
0.014
85.
tet rnchlorethylene
93
3
*
ND
*
ND
*
87.
t rlchloroethylene
93
3
ND
ND
*
ND
*
89.
aldrln
93
3
**
W)
«-*
**
**
90.
dleldrln
93
3
ND
ND
**
ND
**
91.
chlordane
93
3
**
**
**
«-*
++
92.
4,4'-DDT
93
3
**
**
+*
**
**
93.
4,4'-DDE
93
3
**
«-*
M>
«-*
++
99.
endrln aldehyde
93
3
++
*+
ND
**
**
100.
heptachlor
93
3
**
«-*
ND
**
*-*
101.
heptachlor epoxide
93
3
ND
ND
**
ND
**
103.
beta-BHC
93
3
+*
**
ND
**
«-*
104.
gamna-RHC
93
3
ND
**
ND
ND
**
105.
delta-BHC
93
3
**
ND
**
**
++
106.
PCB-1242 (c)
93
3
**
**
*-*
**
**
107.
PCB-1254 (cj
108.
PCB-1221 (c)
109.
PCB-1232 (d)
93
3
«-*
«-*
**
«-*
«-*
w
M
3
>
W
~<
>
c
2
M
SI
c
2
(/)
C
ffl
n
>
t-3
m
o
o
w
K
w
w
n
-------
Table V-24 (Continued)
PRIMARY ALUMINUM SAMPLING DATA
TREATMENT PLANT SAMPLES - PLANT C
Pollutant
Toxic Pollutants
O
Ln
110.
111.
HZ.
114.
115.
117.
11R.
119.
120.
121.
122.
123.
124.
125.
126.
127.
128.
(d)
PCB-1248 (d)
PCB-1260 (d)
PCB-1016
nntImony
arsenic
beryl1lum
cadmium
chromium
copper
cyanide
lead
mercury
nickel
se tenlun
a 11ve r
thai 1lum
7. Inc
Nonconventlonal
aluminum
calclura
chemical oxygen demand (COD)
fluoride
¦agnealum
phenols (total; by 4-AAP Method)
total organic carbon (TOC)
Convent tonal
oil b grease
total suspended solids (TSS) -
P«
St ream
Code
93
93
93
93
93
93
93
93
93
93
93
93
93
93
93
93
93
93
93
93
93
93
93
Sample
TrPe
Source
<0.10
<0.01
<0.001
<0.002
<0.005
0.009
<0.020
0.0001
<0.005
<0.01
<0.02
<0.1
<0.060
0.100
13.0
3.3
Day 1
Concentrations (mg/1)
.Day 2 Day 3
<0.10
<0.01
<0.001
<0.002
<0.005
<0.006
0.246
<0.020
0.0001
<0.005
<0.01
<0.02
<0.1
<0.060
2.000
15.0
28
7.8
3.2
0.017
10
32
6.8
<0.10
<0.01
<0.001
0.008
0.020
0.007
0.216
<0.020
0.002
<0.005
<0.01
<0.02
<0.1
<0.060
2.000
10.0
22
9.4
2.9
0.013
7
2
14
6.7
<0.10
<0.01
<0.001
<0.002
0.020
<0.006
0.223
<0.020
0.0001
<0.005
<0.01
<0.02
<0.1
<0.060
2.000
10.0
22
7.4
3.1
0.012
7
Average-
<0.10
<0.01
<0.001
0.003
0.01
<0.006
0.228
<0.020
0.0007
<0.005
<0.01
<0.02
<0.1
<0.060
2.000
11.7
24
8.2
3.07
0.014
8
~d
W
M
3
>
SO
K
>
t"1
G
3
M
55
G
2
to
G
a
o
>
H
M
O
O
w
K
to
M
O
H
3.0
9
2.5
18.3
(a), (b), (c), (d) Reported together
-------
Table V-25
PRIMARY ALUMINUM SAMPLING DATA
TREATMENT PLANT SAMPLES - PLANT D
Vo 1 luiant
S C ream
Code
Sample
Type
Source
Day 1
O
o\
Tox i c PolLutants
39. f luoranthene
6b. his(I-ethy IhexyI) phthalate
68. dl-n-butyl phchalace
76. chryscnc
84. pyrene
85. tetrach lorocthy1ene
Hb. toluene
8 7. t r I cl» lorocthy 1 ene
89. aLdrln (b)
90. di c1drIn (b)
91. chIordane
92. 4,4'-DDT (b)
91. 4,4'-DUE (b)
94. 4,4'-DDL) (b)
95. a Ipha-endofluIfon (b)
96. beta-endosuIfan (b)
97. endosultan sulfate (b)
98. endrin (b)
99. endrin aLdehyde (b)
100. heptachlor (d)
IU1. heptachlor epoxide (b)
102. alpha-BHC (b)
103. bet a - BMC (t>)
104. gamma-BHC (b)
105. delra-BHC (b)
106. PCB-1242 (c)
107. PCB-1254 (c)
108. PCB-1721 (c)
109. PCH-I ? 3 2 (d)
I 10. PCH-I?48 (d)
111. l'CH-1 260 (d)
I 12. FCH-1016 (d)
113. tox.iphene
114. ant imony
113. a r.sofi Ic
lib. ashostos (MKI.)
117. be ry11 Ium
118. ciiHm i um
119. chroini um
120. copper
12 1. cyan i de
27
2 7
27
2/
ll
2 7
2/
2 7
27
0 .060
ND
NL>
0. 140
0.080
0.122
0.01 7
0.13b
Concent rat Ions (ma/I)
Day 2 Day
<0.015
<0.015
0.0 1
<0.002
1.2 (MKL)
<0.0^0
<0.2 00
<0.240
0.050
0.005
ND
Nl)
1 .1
0.1
<0 .00^
<0.020
0 .0 i9
0.0)5
0 .004
0.006
U).00
K
>
t-1
C
s
M
2:
c
s
(/)
G
m
n
>
•-3
m
o
o
»
~<
c/)
w
o
t-3
-------
Table V-25 (Continued)
PRIMARY ALUMINUM SAMPLING DATA
TREATMENT PLANT SAMPLES - PLANT D
Po Mutant
Toxic Pollutants
122.
123.
124.
125.
126.
127.
128.
lead
mercury
nlcke1
selenium
allver
thai1lua
zinc
St ream
Code
27
27
27
27
27
27
27
Sample
..Iype
Source
Day 1
<0.600
0.0001
<0.500
0.035
<0.250
<0.050
0.560
Concentrations
P-y z 1
0.124
0.0002
0.060
0.025
<0.025
<0.050
0.118
Day 3
<0.060
0.0002
<0.050
0.008
<0.025
<0.050
2.000
Average"
0.04
0.0002
0.02
0.023
<0.100
<0.050
0.891
W
H
3
>
W
~<
>
c:
s
o
Nonconventlonal
aluminum
calclum
chemical oxygen demand (COD)
fluoride
nagneslun
phenols (total; by 4-AAP Method)
total organic carbon (TOC)
Conventlonal
oil t grease
total auspended solids (TSS)
pH (standard units)
27
27
27
27
27
27
27
27
27
27
2.0
29.0
1)1
2.4
8.0
0.083
63
10
100
7.3
3.0
43.8
170
1
7
0
41
9
3
054
20
80
8.0
4.0
46.5
75
3.0
7.5
0.047
27
1
59
7.6
3.0
39.8
125.3
2.43
7.6
0.061
43.7
10.3
79.7
to
c:
to
o
>
^3
M
O
O
W
K
W
M
O
^3
-------
Table V-26
PRIMARY ALUMINUM SAMPLING DATA
TREATMENT PLANT SAMPLES - PLANT E
Pollutant(a)
Toxic Pollutants
S t reare
Samp 1e
-J
O
00
1 .
34.
35.
39.
62.
66.
67.
72.
73.
74.
75.
76.
77.
78.
81 .
79.
80.
82.
81.
84.
114.
115.
II/.
118.
119.
120.
121 .
122.
123.
acenaphrhene
? , 4-dlmenyl-phenoI
2 ,4-dlnltrotoluene
f luor.inchene
N-n(t rosorM phenylamine
bls(2-ethyIhexyI) phthalate
butyl benzyl phrhalate
benzo(a)ant hracene
benzo(a)pyrene
benzo(b) fluoramhenc (b)
bcny.o(k) f luoranchene (b)
chrysent*
accnaphthylone
anthracene (c)
phcnanthren* (c)
btMi/.o/gh I) pery lene
f luorcne
dlhenzo(a,h)anthracene
indeno (I,2,3-cd)pyrene
pyrene
antlmony
arsenic
bt*ry 11 (um
cadmlum
chromluro
copper
cyanide
I ead
mercury
Code
Type
Source
Day 1
Day 2
Day 3
Av*»rafce
141
3
*
0.42
ft
0.3
0.24
I'll
3
NO
NL)
ND
0.28
0.28
141
J
NO
0.2
NO
ND
0.2
UI
3
*
22.3
0.75
12
12
141
3
NO
Nl)
ND
o.ou
0.014
141
3
*
3.1
NO
0.0 j 1
1 .6
1 /. 1
3
NO
ND
ND
0.012
0.01 2
141
3
NL)
10
0.2*.
1 1
7
141
3
Nl)
10
0.24
5. /0
5.3
141
3
*
<1 1
o.n
5.7
5.64
141
3
Nl)
2 1
0.4 3
18
14
141
3
Nl)
0.02
NO
0.019
0 .020
141
3
•
0.5
NO
0 .6}
0.6
14 1
141
3
Nl).
3
NO
NO
J
141
3
NO
0.01 7
Nl)
1 .1
0.558
141
3
NO
2
Nl)
2.9
2.5
141
3
NO
2.1
ND
0.65
.4
141
3
*
23
0.80
12.b
12
14 1
3
<0.00")
0.84
0.5U
1
0. /8
1 48
1
<0.000')
<0.0005
141
3
<0.U0l
1 .8
1 .9
0.64
.4
148
0.1 24 3
0.1743
141
1
<0.0005
D .060
0.030
0 .060
0.050
1 48
0.0448
0.0448
141
1
<0.001
0.08
0.OB0
0.10
0.09
148
0.004
0.004
141
3
I) .008
0.02 3
0 .080
o .01 rt
0 .04
14H
0.1
0.1
141
1
0.029
0.12
0.U8U
0.11
0.1
148
0. 744
0. luu
141
1
0.14
200
1 6U
1 60
1 7 3
1 48
<0.01
82
82
14 1
3
0.01
0.45
0. ^
O.'jS
0 .46
14H
0.21
0.2 1
141
3
0.0002
<0.0002
<0.0002
<0 .0002
<0.0002
148
1
0.021 t
0.0213
*
H
s
>
so
K
>
tr>
c;
s
(—I
2:
c
3
ui
a
m
o
>
H
pi
o
o
JO
K
in
in
o
H
-------
Table V-26 (Continued)
PRIMARY ALUMINUM SAMPLING DATA
TREATMENT PLANT SAMPLES - PLANT E
o
vo
Po L lutant(a)
Toxic Pollutanta (Oont.)
Sc ream
Code
Sample
TyPe
Source
Day I
Concentrations (mn/l)
Day 2 Day 3
Average
124. n1 eke 1
141
3
0.012
0.45
0.37
0.56
0.46
U8
1
0.122
0.122
125. se len turn
141
3
0.2 SO
3.0
1 .1
1 .2
1 .8
148
1
0.0 to
0 .030
126. s 11 ver
141
3
0.005
0.40
0. 70
0.62
0.60
148
1
<0.00 2
<0.002
12 7. rhal 1 liim
141
3
<0.001
0.5)
0.61
0.69
0.61
148
1
<0.001
<0.001
128. zinc
141
3
0.02
0.10
0.08
0.12
0.10
148
1
0.056
0.056
Conventlona1
oil & grease
141
1
<1
1 .500
42
1 , 30(1
94 7
total suspended solids (TSS)
141
3
2,000
150
3,900
2,01/
pH
141
1
5
9
11
Nonconventlona I
amnion 1 a
141
1
0.44
2.0
13
7.9
7 .6
chemical oxygen demand (COD)
141
3
1 .800
1 .100
I . 300
1 .730
f luor Ide
141
J
630
8/0
670
720
total organic carbon (TOC)
141
3
630
1 ,400
2 , 300
1 ,440
phenols (total; by 4-AAP method)
141
3
0.014
0.36
0.50
0.4 7
0.44
<48
1
<0.001
0.090
0.090
(a) Stream 141 was not analyzed for the volatile or pesticide fractions of toxic organic pollutants. Stream 143 was
not analyzed for any toxic organic pollutant and only total phenols of the nonconventiona1 pollutants.
(b), (c) Reported together
-------
Table V-27
PRIMARY ALUMINUM SAMPLING DATA
TREATMENT PLANT SAMPLES - PLANT F
Stiearn
Concentrations (mg/1. except as noted)
—I
M
O
Po I lutant(a)
Code
Type
Source
Da^ t
Day 2
Day 3
AveraR
Tox ic
I'o I lutant s
1 .
acenaph thene
1 36
3
NU
0.025
ND
0.027
0.026
37.
1 , 2-.
benzo(k)fluoranthene
1 36
3
ND
NU
NU
4.4
4.4
76.
clirysene
1 36
NU
7.5
3
10
6.8
78.
81 .
anthracene (b)
phenanrhrene (b)
1 36
3
*
<7.8
<6.8
<5.3
<6.63
79.
hen 7.0 (nh i )pcry lene
136
3
NU
Nl)
NU
0.920
0.920
80.
f 1 uorone
1 36
NU
ND
0.083
0.11
0.097
82.
d i ben 7.0(a,h)anlh racene
1 36
3
ND
ND
ND
0.8
0.8
83.
i n d e n o (1 ,2 , 3 - c d) p y r e n e
1 36
3
ND
1 .2
ND
0. /
0.95
84.
py rene
1 )6
3
ND
14
12
12
1 3
114.
ant i m
~<
>
G
2
M
Z
G
3
to
G
QJ
o
>
H
W
O
O
50
K
to
W
O
H
-------
Table V-2/ (Continued)
PRIMARY ALUMINUM SAMPLING DATA
TKKATMKNT
PLANT
SAMPLES -
PLANT
F
St ream
5«imp Le
Concent rat Ions
(nig / 1 , except as
noted)
Pollulant(a)
Code
Type
Source
Day 1
Day 2
?a.Z. J
Ave rage
Toxic
Pollutants (Cont.)
117.
bury I 1 i urn
1 J 6
3
<0.0005
0.02
0.03
0.03
0.03
118.
L'.iilin i uin
1 36
3
<0.001
0.05
0.05
0.05
0.05
1 19.
chromium
1 36
3
0.01 1
0. 028
0.028
0. 014
0.023
120.
coppe r
1 36
3
0. 041
0.08
0.06
0. 07
0.07
121.
cyanide
1 36
1
1. 3
1.4
1.5
1.4
122.
lead
1 36
3
0. 1 7
0. 12
0.4
0. 27
0. 26
123.
mercury
1 36
3
<0.0002
<0.0002
<0.0002
<0.0002
<0.0002
1 24.
nickel
1 36
3
<0.005
0. 26
0. 22
0. 21
0.23
125.
selen i um
1 36
3
<0.008
0. 16
0.008
<0.008
<0.06
126.
ai 1 ver
1 36
3
<0.001
0.011
0.006
0.003
0.00 7
127.
tha1 Ii um
1 36
3
<0.001
0. 31
0. 35
0. 39
0. 35
128.
i i nc
136
3
0.04
0.20
0. 14
0. 17
0. 1 7
Nonconvent 1ona1 Pollutants
ammonia
1 36
1
3. 3
0. 2
3.4
2. 3
chemical oxygen demand (COD)
1 36
3
1,200 1,200 1,200
1 , 200
fluor1de
136
3
2,
000 1 ,
900 2.
000
1, 967
phenols (lolaL; by 4-AAP method)
1 36
1
<0.001
<0.001
<0.001
<0.001
total
organic carbon (TOC)
1 36
3
5 70 1,300
460
780
Conventional Pollutants
oil and grease
136
1
1 3
18
14
1 5
tota L
suspended solids (TSS)
1 36
3
140
140
160
146
pH (standard units)
1 36
1
5
7. 7
8
8
(a)
No samples were analyzed for
the acid, pesticide,
or volatlie
toxic organic fractions.
(b)
Reported together.
~d
50
M
3
>
50
K
>
t-«
c:
s
M
5S
G
3
c/i
c:
a
n
>
i-3
w
Q
o
50
K
to
w
0
1-3
1
<
-------
PRIMARY ALUMINUM SUBCATEGORY
SECT
TABLE V-28
REPORTED PRESENCE OR ABSENCE OF TOXIC POLLUTANTS
(From Dcp Responses)
Pollutant
Known
Present
Believed
Present
Believed
Absent
Known
Absent
Acenaphthene
Fluoranthene
1,2-benzanthracene
Benzo(a)pyrene
Chrysene
Pyrene
3,4-benzofluoranthene
Benzo(k)fluoranthene
Acenaphthylene
Anthracene
Benzo(ghi)perylene
Fluorene
Phenanthrene
Dibenzo{a,h)anthracene
Indeno(1,2,3-cd)pyrene
Methyl bromide
Naphthalene
Pentachlorophenol
Tetrachloroethylene
Toluene
Antimony
Arsenic
Cadmium
Chromium
Copper
Cyanide
Lead
Mercury
Nickel
Selenium
Silver
Thai1ium
Zinc
0
0
0
0
1
0
0
0
0
0
0
2
0
0
0
0
0
0
0
0
0
3
5
6
7
16
0
8
4
6
8
8
7
8
5
5
5
9
5
8
9
4
4
1
6
1
0
1
2
3
2
3
5
4
5
3
3
1
3
0
3
20
19
19
19
20
19
22
22
21
19
22
18
19
23
23
26
21
27
27
27
21
17
16
16
14
5
19
21
23
22
22
24
16
3
2
0
0
0
0
0
0
1
0
0
0
0
0
0
1
1
0
1
0
4
4
4
2
1
0
2
2
0
3
1
2
712
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - V
Table V-29
SOURCE WATER CHARACTERI STICS
Parameter Concent ration(mg/1)
Sb
0.015
CM (T)
<0.01
Ni
<0.1
TSS
2.
0 & G
<1
pH (std units)
6.95
Aluminum
<0.1
Calcium
50
Chlor ide
36
Fluor ide
0.34
Iron
0.80
Total Dissolved Solids
273
Alkalinity (as CaC03)
198
713
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - V
Table V-30
RAW WASTEWATER CHARACTERISTICS
POTLINE SCRUBBER BLOWDOWN
Paramete:
Sb
CN {T)
Ni
No.
Values
10
10
10
Concentration (mg/1)
Average Range
4 . 68
38.9
1.0
1.13 - 10.0
27.4 - 47.5
0.70 - 1.40
TSS
0 & G
pH (std units)
Aluminum
Calcium
Chlor i de
10
5
10
9
9
130
9
24
3.7
1275
75
6
8.0
20
1.5
1200
238
14
9.42
27
9
1400
Fluoride 10
Iron 9
Total Dissolved 10
Solids (Percent)
Alkalinity
(as CaCC>3)
Turbidity (NTU)
Temperature (°C)
10
10
874
12.1
6.18
5300
3.8
34. 5
237
9.5
5.02
4900
3.2
33.3
1260
16
6.74
7300
4 . 6
37 . 2
714
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - V
Table V-31
CONCENTRATION OF PAH IN POTLINE WASTEWATER
Concent ra t ion (mg/1)
PAH Average Range
Napthalene ND ND
Acenapthylene ND ND
Acenapthene 0.030 0.02 - 0.040
Fluorene ND ND
Phenanthrene & ND ND
Anthracene
Fluoranthene 2.740 1.840 - 3.670
Pyrene 2.000 1.410 - 2.900
Chrysene S> 2.230 1.780 - 3. 200
Benzo(a)anthracene
3,4-Benzofluoranthene & 0.790 0.600 - 1.060
Benzo(k)fluoranthene
Benzo(a)pyrene 1.100 0.700 - 1.820
Dibenzo(a,h)anthracene 0.140 0.090 - 0.200
Indeno(1,2,3-cd)pyrene ND ND
Benzo(ghi)perylene 0.310 0.220 - 0.440
NOTES:
ND - Not Detected (quantification limit = 0.010 mg/1)
All values reported in mg/1 without correction for recovery
Analysis by Method 625.
Average derived from 9 data points.
715
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - V
Table V-32
SAMPLE DATA SUMMARY OF PAH ANALYSIS
Potline Scrubber Liquor
Clarifier Filter Act. Carbon
PAH Effluent Effluent Effluent
Naphthalene ND ND ND
Acenaphthylene ND ND ND
Acenaphthene 0.010 0.010 ND
Fluorene ND ND ND
Phenanthrene & ND ND ND
Anthracene
Fluoranthene 0.170 0.114 ND
Pyrene 0.110 0.079 ND
Chrysene & 0.040 0.023 ND
Benzo(a)anthracene
3,4-Benzofluoranthene & 0.020 0.010 ND
Benzo(k)fluoranthene
Benzo(a)pyrene 0.020 0.010 ND
Dibenzo(a,h)anthracene ND ND ND
Indeno(1,2,3-cd)pyrene ND ND ND
Benzo(ghi)perylene ND ND ND
NOTES:
ND - Not Detected (quantification limit = 0.010 mg/1)
All values reported in mg/1 without correction for recovery
Analysis by Method 625.
Average derived from 8 clarifier data points and 9 filter
effluent data points.
716
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - V
Table V-33
SAMPLE DATA SUMMARY OF METALS ANALYSIS
Potline Scrubber Liquor
Clarifier Filter
Parameter Effluent Effluent
Ant imony
3.3
2.99
Nickel
00
in
o
0.57
Aluminum
2.2
1.9
Fluoride
212
206
TSS
02
15
717
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - V
Source
Water
(River)
Fctline
Lime
Poi.ut1on
Settle
3.4 MGD
Treated
Sanitary
Wastes
0.1 MGD
Plant
Runoff
(
\
0,
Ar.ode
Contact
Cooling
Water3
A
.192
92\
A
Pot room
L
Air
(
Pollution
\
Cont rol
13
13.? MGD
Lagoon
-i zSk
Discharge
-»•
17.6 MGD
- Sample Site
A - Waste Screair
Code Number
Figure V-1
SAMPLING SITES AT PRIMARY ALUMINUM PLANT A
LThis plant uses the VSS cell configuration, however, the paste
is formed into briquettes for insertion into the carbon anode.
718
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - V
source
Water
(River &
*'e 1 I Watcr)
Linings
Cryolite
Recoverv
Thickener
Podlne
Air
Pollution
Control
underf:av
0.058 MGd
A
Ai 2\
VOA Blank
Excess i
'»'ell Uater V
0.29 MCD
J
Lis*
Mixing
Cryciite
Recovery
liat Tray
Thlckantr
Underflow
0.022 MCD
0.37 MGD
Ac id
(h2£06)
Pond
Neut rali-
zaticn
0.3 7 MCD
Non-
Con tact
Cooling
Water
A
ATn r
Contact
Coaling
Water
Blowdovn
0.22 "CD
Discharge
Figure V-2
SAMPLING SITES AT PRIMARY ALUMINUM PLANT B
719
-------
PRIMARY ALUMINUM SUBCATEGORY SECT
- V
/09l\
VOA Bl&r.k
Lime
j Caustic
I Lagoon
Caustic
Clarifltd
Vacuus
Filtration
—®~
5.66 MGD
Sanitary
Wastes
Son-
Contact
Cooling
Water
Degassing
A-tr
?ollutIon
Con!rol
Chlorine
Lagoon
Cooling
Towers
Blovdown
Anode Bake
Source
Water
(River)
Pocrooa
Air
Pollution
Concrol
Anode Paste
Plant Air
Pollution
Control
Figure V-3
SAMPLING SITES AT PRIMARY ALUMINUM PLANT C
720
-------
PRIMARY ALUMINUM SUBCATEGORY
SECT
Sludge
Recycle
Rcc vcle
1.3 MGD
Settlin
Potrootr Air
Pollut ion
Control Cryolite
Kiln
Scorr.
Water
Anode
Contact
Cooling
Anode Paste
Plan: Scrubber
Liquor
Decant
Pond
0. 15
y.cD
1 A-iode Bake
Plan: Air
•Pollution Control
1
Decar. t
Pond
To Pctroorr.
Scrubber
Ncncentact
Cooling
Bicwdovr.
Oil
f cr
Reclamacion
Surge
Pond
XN
Discharge
1.6 MCD
Emergency Overflow
f'
1. Casting Contact
| Coolir.g Water
Figure V-4
SITES AX PRIMARY ALUMINUM PLANT D
SAMPLING
721
-------
PRIMARY ALUMINUM SUBCATEGORY
SECT - V
VOA Blank
Rectifitr
Ceding
Water
Steam
Boiler
Blovdovr.
a Polv-.er
water
Anode
Paste
Plar.t
Thickener
system
0.0364 MGD
Seeding
0.0"
Cathode
Storage
Cryolite
Recovery
0.2 MGD
Potline Air
Pollution
Control
«-"6 -V-"D
Rerining anc
Degassing
Air PoLlu
tion Control
0.020 XC.j
Casting
Contact
Cooling
Water
9.6 MGD
Discnaree
Figure V-5
SAMPLING SITES AT PRIM Mi x ALUMINUM PLANT E
722
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - V
water
A
VOA Black
Recvcle With Caustic Soda Addition
1.03 MGD
Ar.oee Bake
Plar.t Air
Pollution
Control.
Sludge
to
Of:-Sice
Disposal
Discbarge
Ajicde
Concacc
/
Cooling
\
0.
Discharge
0.202 MGD
Figure V-6
SAMPLING SITES AT PRIMARY ALUMINUM PLANT F
723
-------
PRIMARY ALUMINUM SUBCATEGORY
SECT - V
THIS PAGE INTENTIONALLY LEFT BLANK
724
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - VI
SECTION VI
SELECTION OF POLLUTANT PARAMETERS
This section examines chemical analysis data presented in Section
V from primary aluminum plants and discusses the selection or
exclusion of pollutants for potential limitation. The basis for
the regulation of toxic and other pollutants is discussed in
Section VI of the General Development Document (Vol I) and each
pollutant selected for potential limitation is discussed there.
That discussion provides information concerning where the
pollutant originates (i.e., whether it is a naturally occurring
substance, processed metal, or a manufactured compound); general
physical properties and the form of the pollutant; toxic effects
of the pollutant in humans and other animals; and behavior of the
pollutant in POTW at the concentrations expected in industrial
discharges.
The discussion that follows describes the analysis that was
performed to select or exclude pollutants for further
consideration for limitations and standards. Pollutants are
selected for further consideration if they are present in
concentrations treatable by the technologies considered in this
analysis. The treatable concentrations used for the toxic metals
were the long-term performance values achievable by lime
precipitation, sedimentation, and filtration. The treatable
concentrations for the toxic organics were the long-term
performance values achievable by carbon adsorption.
After proposal, the Agency re-evaluated the treatment performance
of activated carbon adsorption to control toxic organic
pollutants. The treatment performance for the acid extractable,
base-neutral extractable, and volatile organic pollutants has
been set equal to the analytical quantification limit of 0.010
mg/1. The analytical quantification limit for pesticides and
total phenols (by 4-AAP method) is 0.005 mg/1, which is below the
0.010 mg/1 accepted for the other toxic organics. However, to be
consistent, the treatment performance of 0.010 mg/1 is used for
pesticides and total phenols. The 0.010 mg/1 concentration is
achievable, assuming enough carbon is used in the column and a
suitable contact time is allowed. The frequency of occurrence
for 36 of the toxic pollutants has been redetermined based on the
revised treatment performance value. As a result, naphthalene,
which was not selected at proposal, has been selected for further
consideration for limitation.
CONVENTIONAL AND NONCONVENTIONAL POLLUTANT PARAMETERS
This study considered samples from the primary aluminum
subcategory for three conventional pollutant parameters (oil and
grease, total suspended solids, and pH) and six nonconventional
pollutant parameters (aluminum, ammonia, chemical oxygen demand,
725
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - VI
chloride, fluoride, total organic carbon, and total phenols).
CONVENTIONAL AND NONCONVENTIONAL POLLUTANT PARAMETERS SELECTED
The conventional and nonconventional pollutants and pollutant
parameters selected for consideration for limitation in this
subcategory are:
aluminum
fluor ide
total suspended solids (TSS)
oil and grease
PH
Aluminum is selected for consideration for limitation for two
reasons: (1) it is the major product of plants in this
subcategory, and (2) it was found at concentrations higher than
those achievable by identified treatment technology (1.49 mg/1)
in three of four samples from three plants.
Fluoride is found primarily in wastewaters from wet scrubbing of
gases from the primary reduction of alumina to aluminum.
Fluorides were measured above the concentration attainable by
identified treatment technology (14.5 mg/1) in 12 of 16 samples
from seven plants. Treatable concent rat ions ranged from 63 to
13,000 mg/1. Therefore, fluoride is selected for consideration
for limitation.
Total suspended solids ranged from 4 to 54,500 mg/1. Eighteen of
18 samples had concentrations above that achievable by identified
treatment technology (2.6 mg/1). Furthermore, most of the
technologies used to remove toxic metals do so by precipitating
the metals. A limitation on total suspended solids ensures that
sedimentation to remove precipitated toxic metals is effectively
operating. Therefore, total suspended solids is selected for
consideration for limitation.
Oil and grease concentrations in the wastewaters sampled ranged
from 2 to 1,400 mg/1 in 18 samples. The processing of coal tar
pitch and coke in the anode paste and bake operations is the
principal source of these pollutants. The concentration in 12 of
the 18 samples exceeded the treatable concentration (10 mg/1).
Thus, this pollutant is selected for consideration for
1imi tat ion.
The pH values observed ranged from 5.0 to 11.0. Effective
removal of toxic metals by precipitation requires careful control
of pH. Therefore, pH is considered for limitation in this
subcategory.
TOXIC POLLUTANTS
The frequency of occurrence of the toxic pollutants in the
wastewater samples taken is presented in Table VI-1 (page 735).
These data provide the basis for the categorization of specific
726
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - VI
pollutants, as discussed below. Table VI-1 is based on the raw
wastewater data from streams 145, 194, 26, 195, 126, 127, 142,
144, 28, 150, 137, and 135 (see Section V). Treatment plant
samples and samples containing nonscope wastewater were not
considered in the frequency count.
TOXIC POLLUTANTS NEVER DETECTED
The toxic pollutants listed in Table VI-2 (page 739) were not
detected in any wastewater samples from this subcategory;
therefore, they are not selected for consideration in
establishing regulations:
TOXIC POLLUTANTS NEVER FOUND ABOVE THEIR ANALYTICAL
QUANTIFICATION LEVEL
Toxic pollutants which are not detectable include those
pollutants whose concentrations fall below EPA's nominal
detection limit. The toxic pollutants listed in Table VI-3
(page 741) were never found above their analytical quantification
concentration in any wastewater samples from this subcategory;
therefore, they are not selected for consideration in
establishing regulations.
TOXIC POLLUTANTS PRESENT BELOW CONCENTRATIONS ACHIEVABLE BY
TREATMENT
The pollutant mercury is not selected for consideration in
establishing limitations because it was not found in any
wastewater samples from this subcategory above concentrations
considered achievable by existing or available treatment
technologies. Mercury was detected at, or above, its 0.0001 mg/1
analytical quantification limit in three of 18 samples from 10
plants. All of the values are below the 0.026 mg/1 concentration
considered achievable by identified treatment technology.
TOXIC POLLUTANTS DETECTED IN A SMALL NUMBER OF SOURCES
Toxic pollutants detectable in the effluent from only a small
number of sources within the subcategory and uniquely related to
only those sources are not appropriate for limitation in a
national regulation. The pollutants listed in Table VI-4 (page
735) were not selected for further consideration for limitation
on this basis.
Although these pollutants were not selected for cons iderat ion in
establishing nationwide limitations, it may be appropriate, on a
case-by-case basis, for the local permit writer to specify
effluent limitations.
Benzene was detected in four of eight samples collected from six
plants. Two of the detected concentrations were below analytical
quantification level. The other two concentrations were 0.013
mg/1 and 0.016 mg/1, which are slightly above the treatable
727
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - VI
concentration. These two samples detected above treatable
concentrations were found at the same plant in two different raw
wastewaters. The same streams in another plant did not contain
benzene. For these reasons, benzene is not considered for
limitation.
2-Chloronaphthalene was measured above its analytical
quantification limit in just one of 19 samples collected at 10
plants. The reported value was 0.041 mg/1; this pollutant was
not detected in any of the other 18 samples. Because it was
found at just one plant, 2-chloronaphthalene is not considered
for limitation.
Chloroform, a common laboratory solvent, was detected in three of
eight samples collected from six plants. Only one concentration
was above the analytical quantification limit and this was above
the treatable concentration. This pollutant is not attributable
to specific materials or processes associated with the primary
aluminum subcategory. Sample contamination is the probable
source of this pollutant? therefore, chloroform is not considered
for limitation.
Bis(2-chloroisopropy1) ether was found above its analytical
quantification limit in just one of 19 samples collected at 10
plants. This pollutant was not detected in 17 other samples.
Therefore, bis(2-chloroisopropyl) ether is not considered for
1imi tat ion.
Methylene chloride was detected in two of eight samples from six
plants. Only one concentration was above the analytical
quantification limit and this was above the treatable
concentration. The reported value (0.055 mg/1) was from potrpom
wet air pollution control raw wastewater. Methylene chloride
from this stream at another plant was not detected. This
pollutant is not attributable to specific materials or processes
associated with the primary aluminum subcategory, but is a common
solvent used in analytical laboratories. There is a high
probability of sample contamination. For these reasons,
methylene chloride is not considered for limitation.
N-nitrosodiphenylamine was detected above its analytical
quantification limit in only one of 19 samples taken at 10
plants. The detected concentration was 0.057 mg/1. Although
this value is above the 0.010 mg/1 considered attainable by
identified treatment technology, N-nitrosodiphenylamine is not
considered for limitation because it was found above a treatable
concentration at only one plant.
Phenol was detected above its analytical quantification limit in
only one of six samples taken from two plants. Although the
0.070 mg/1 concentration observed is above the 0.010 mg/1
treatable concentration, phenol is not considered for limitation
because it was found at only one plant.
Bis(2-ethylhexyl) phthalate was found above its analytical
728
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - VI
quantification limit in 12 of 19 samples from 10 plants. The
concentrations observed ranged from 0.011 to 2.50 mg/1. The
presence of this pollutant is not attributable to materials or
processes associated with the primary aluminum subcategory. It
is commonly used as a plasticizer in laboratory and field
sampling equipment. EPA suspects sample contamination as the
source of this pollutant. Therefore, bis(2-ethylhexyl) phthalate
is not considered for limitation.
Butyl benzyl phthalate was found above its analytical
quantification limit in four of 19 samples from 10 plants. The
concentrations ranged from 0.012 to 0.085 mg/1. The presence of
this pollutant is not attributable to materials or processes
associated with the primary aluminum subcategory. It is commonly
used as a plasticizer in laboratory and field sampling equipment.
EPA suspects sample contamination as the source of this
pollutant. Therefore, butyl benzyl phthalate is not considered
for limitation.
Di-n-butyl phthalate was found above its analytical
quantification limit in three of 19 samples from 10 plants. The
concentrations observed ranged from 0.022 to 0.126 mg/1. Two of
the three samples showed concentrations above the 0.010 mg/1
treatable concentration. The presence of this pollutant is not
attributable to materials or processes associated with the
primary aluminum subcategory. It is commonly used as a
plasticizer in laboratory and field sampling equipment. EPA
suspects sample contamination as the source of this pollutant.
Therefore, di-n-butyl phthalate is not considered for limitation.
3,4-Benzofluoranthene was detected above its analytical
quantification limit in just one of 19 samples from 10 plants.
Since it was found in only one plant, 3,4-benzofluoranthene is
not considered for limitation.
Benzo(k)fluoranthene was also found above its analytical quanti
fication limit in just one of 19 samples. Therefore, benzo(k)-
fluoranthene is not considered for limitation.
Acenaphthylene was detected in six of 19 samples from 10 waste
streams sampled. This pollutant was present below the
quantification limit in five of the samples. Only one sample
contained a treatable concentration of acenaphthylene. Since it
was found treatable at only one plant, acenaphthylene is not
considered for limitation.
Indeno(1,2,3-cd)pyrene was detected above its analytical
quantification limit in two of 19 samples taken from 10 plants.
Since it was found in only two plants, indeno(1,2,3-cd)pyrene is
not cons idered for 1imi tat ion.
The first group of PCB's (polychlorinated biphenyls) was detected
above its analytical quantification limit in one of three samples
taken at three plants. The group contains PCB-1242, PCB-1254,
and PCB-1221, which are reported together since they are not
729
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - VI
clearly separated by the analytical protocol used in this study.
Because these pollutants were detected in a small number of
sources, they are not considered for limitation.
Beryllium was found above its analytical quantification limit in
12 of 21 samples taken from 10 plants. Concentrations ranged
from 0.02 to 0.4 mg/1. Only one sample contained a concentration
above the 0.20 mg/1 considered attainable by identified
technology. Because it was found at a treatable concentration at
only one plant, beryllium is not considered for limitation.
Silver was measured above its analytical quantification limit in
10 of 21 samples. Three samples contained treatable
concentrations of silver, all measured at the same plant.
Therefore, silver is not considered for limitation.
TOXIC POLLUTANTS SELECTED FOR FURTHER CONSIDERATION FOR
LIMITATION
The toxic pollutants listed below are selected for further
consideration in establishing limitations for this subcategory.
The toxic pollutants selected are each discussed following the
list.
1.
acenaphthene
39.
fluoranthene
55.
naphthalene
72.
benzo(a)anthracene
73.
benzo(a)pyrene
76.
chrysene
78.
anthracene (a)
79.
benzo(ghi)perylene
80.
fluorene
81.
phenanthrene (a)
82.
dibenzo(a,h)anthracene
84.
pyrene
114.
antimony
115.
arsenic
116 .
asbestos
118.
cadmium
119 .
chromium
120 .
copper
121 .
cyanide
122 .
lead
124 .
nickel
125 .
selenium
128 .
zinc
(a) Reported together as a combined value.
Acenaphthene was found above its analytical quantification limit
in 14 of 19 samples from 10 plants, with concentrations ranging
from 0.011 to 29.0 mg/1. Ten of those samples, representing five
plants, were above the 0.010 mg/1 concentration attainable by
identified treatment technology. Therefore, acenaphthene is
730
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - VI
selected for further consideration for limitation.
Fluoranthene was measured above its analytical quantification
limit in 15 of 19 samples from 10 plants with concentrations
ranging from 0.073 to 32.0 mg/1. All 15 samples, representing
seven plants, were above the 0.010 treatable concentration.
Therefore, fluoranthene is selected for further consideration for
limitation.
Naphthalene was detected in II of 19 samples collected from 10
plants. Seven of the 11 detected concentrations were above the
treatable concentration (0.010 mg/1) attainable by identified
treatment technology. These concentrations ranged from 0.02 mg/1
to 7.7 mg/1. Seven of the 10 raw wastewater streams sampled were
found to contain naphthalene. Therefore, naphthalene is selected
for further consideration for limitation.
Benzo(a)anthracene was found above its analytical quantification
limit in 15 of 19 samples, taken from 10 plants, with
concentrations ranging from 0.014 to 14.0 mg/1. Fourteen
samples, representing seven plants, were above the 0.010 mg/1
range considered attainable by identified treatment technology.
Therefore, benzo-(a)anthracene is selected for further
consideration for limita-tion.
Benzo(a)pyrene was found above its analytical quantification
limit in 13 of 19 samples, taken from 10 plants, with
concentrations ranging from 0.017 to 11.0 mg/1. Twelve samples,
representing six plants, were also above the 0.010 mg/1
concentration considered attainable by identified treatment
technology. Therefore, benzo(a)pyrene is selected for further
consideration for limitation.
Chrysene was measured above its analytical quantification limit
in 15 of 19 samples, taken from 10 plants, with concentrations
ranging from 0.030 to 30.0 mg/1. There were 14 samples,
representing seven plants, above the 0.010 mg/1 concentration
considered attainable by identified treatment technology.
Therefore, chrysene is selected for further consideration for
limitation.
The toxic pollutants anthracene and phenanthrene are not clearly
separated by the analytical protocol used in this study; thus,
they are reported together. The sum of these pollutants was
measured at concentrations greater than their analytical
quantification limit in 12 of 19 samples, collected at 10 plants,
with concentrations ranging from 0.029 to 22.0 mg/1. Eleven of
the 12 samples, representing five plants, were above the 0.010
mg/1 treatable concentration. Therefore, anthracene and
phenanthrene are selected for further consideration for
.limitation.
Benzo(chi)perylene was found above its analytical quantification
limit in six of 19 samples, taken from 10 plants, with
concentrations ranging from 0.019 to 2.40 mg/1. Five of the six
731
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - VI
samples, representing four plants, were above the 0.010 mg/1
concentration attainable by identified treatment technology.
Therefore, benzo-(ghi)perylene is selected for further
consideration for limitation.
Fluorene was measured above its analytical quantification limit
in nine of 19 samples, taken from 10 plants, with concentrations
ranging from 0.039 to 5.30 mg/1. All nine samples, representing
four plants, were above the 0.010 mg/1 concentration attainable
by identified treatment technology. Therefore, fluorene is
selected for further consideration for limitation.
Dibenzo(a,h)anthracene was found above its analytical
quantification limit in five of 19 samples, taken from 10 plants,
with con centrations ranging from 0.012 to 1.9 mg/1. All five
samples, representing four plants, were above the 0.010 mg/1
concentration attainable by identified treatment technology.
Therefore, dibenzo(a,h)anthracene is selected for further
consideration for limitation.
Pyrene was found above its analytical quantification limit in 16
of 19 samples, taken from 10 plants, with concentrations ranging
from 0.05 to 34.0 mg/1. All 16 samples, representing eight
plants, were above the 0.010 mg/1 concentration attainable by
identified treatment technology. Therefore, pyrene is selected
for further consideration for limitation.
Antimony was measured above its analytical quantification limit
in 14 of 21 samples, taken from 11 plants, with concent rat ions
ranging from 0.05 to 1.5 mg/1. Since five samples, representing
three plants, were also above the 0.47 mg/1 concentration
attainable by identified treatment technology, antimony is
selected for further consideration for limitation. Selection of
antimony is further justified based on the analytical data
collected during the Agency's pilot scale treatability study.
Antimony was found in 10 of 10 samples all above 1 mg/1.
Arsenic was found above its analytical quantification limit in 17
of 21 samples, taken from 11 plants, with concentrations ranging
from 0.006 to 1.5 mg/1. Seven samples, representing five plants,
were above the 0.043 mg/1 concentration attainable by identified
treatment technology. Therefore, arsenic is selected for further
consideration for limitation.
Asbestos (chrysotile) was measured above its analytical
quantification limit in the one raw wastewater sample analyzed
for this pollutant. The measured value was 310 million fibers
per liter (MFL) which is well above the value of 10 million
fibers attainable by the identified treatment technology. At the
plant where it was detected, both the source water and the
wastewater discharge contained negligible concentrations of
asbestos. Asbestos is considered for further limitation since it
was detected above a treatable concentration in the only sample
it was analyzed for.
732
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - VI
Cadmium was measured above its analytical quantification limit in
10 of 21 samples, taken from 11 plants, with concentrations
ranging from 0.0026 to 0.2 mg/1. Eight samples, representing
four plants, were above the 0.049 mg/1 concentration attainable
by identified treatment technology. Therefore, cadmium is
selected for further consideration for limitation.
Chromium was found above its analytical quantification limit in
17 of 21 samples, taken from 11 plants, with concentrations
ranging from 0.006 to 6.0 mg/1. Three samples, representing two
plants, were above the 0.07 mg/1 concentration attainable by
identified treatment technology. Therefore, chromium is selected
for further consideration for limitation.
Copper was measured above its analytical quantification limit in
20 of 21 samples, taken from 11 plants, with concentrations
selected for further consideration for limitation.
Lead was . found in concentrations above its analytical
quantification limit in 15 of 21 samples, taken from 11 plants,
with concentrations ranging from 0.008 to 5.0 mg/1. Twelve
samples, representing six plants, were above the 0.08 mg/1
concentration attainable by identified treatment technology.
Therefore, lead is selected for further consideration for
limitation.
Cyanide was found above its analytical quantification limit in 20
of 22 samples, taken from 12 plants, with concentrations ranging
from 0.002 to 180.0 mg/1. Since 10 samples, representing five
plants, were also above thel.l mg/1 concentrations attainable by
identified treatment technology (refer to Section VII - Pilot
Scale Treatability Study), cyanide is selected for further
consideration for limitation.
Nickel was measured above its analytical quantification limit in
17 of 21 samples, taken from 11 plants, with concentrations
ranging from 0.014 to 4.0 mg/1. Since 11 samples, representing
six plants, were also above the 0.22 mg/1 concentration
attainable by identified treatment technology, nickel is selected
for further consideration for limitation. Selection of nickel is
further justified based on the analytical data collected during
the Agency's pilot scale treatability study. Nickel was found in
10 of 10 samples all greater than 0.22 mg/1.
Selenium was found above its analytical quantification limit in
14 of 21 samples, taken from 11 plants, with concentrations
ranging from 0.01 to 44.0 mg/1. Eight samples, representing two
plants, were above the 0.20 mg/1 concentration attainable by the
identified treatment technology. Therefore, selenium is selected
for further consideration for limitation.
Zinc was measured above its analytical quantification
concentration in 18 of 21 samples taken from 11 plants, with
concentrations ranging from 0.01 tc 1.0 mg/1. Seven samples,
representing three plants, were above the 0.23 mg/1 concentration
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - VI
attainable by the identified treatment technology. Therefore,
zinc is selected for further consideration for limitation.
734
-------
Table VI-1
FREQUENCY OF OCCURRENCE OF TOXIC POLLUTANTS
PRIMARY ALUMINUM
RAW WASTEWATER
An.ilyt loll
-J
OJ
Ln
(Juanr i f Icat Ion
Treatable
Number of
Number of
Concentration
Concent ra-
Streams
Samples
Pollutant
(tnR/l)(n)
tion (mR/l)(b)
Analyzed
Analyzed
ND
1. acenaphthenc
0.010
0.010
10
19
5
2. acrolein
0.010
0.010
6
8
8
aery loni tr I le
0.010
0.010
6
8
8
!*. benzene
0.010
0.010
6
8
t•
benzidine
0.010
0.010
10
19
19
6. carlxin tetrachloride
0.010
0.010
6
8
8
7. chlorobenztTie
0.010
0.010
6
8
8
8. 1 ,2 ,4-t richlorotienzone
0.010
0.010
10
19
19
9. hex.ichlorobenzene
0.010
0.010
10
19
19
10. 1,2-dichloroethane
0.010
0.010
6
8
H
11. 1 ,1 , l-trichloroethane
0.010
0.010
6
8
8
1 2. hexach loroethano
0.010
0.010
10
19
19
13. 1,1-dichloroethane
0.010
0.010
6
8
8
14. 1,1,7-trichloroethnne
0.010
0.010
6
8
8
15. 1 ,1 ,2,2-tetr.ichloroothane
0.010
0.010
6
8
8
16. chloroelhatte
0.010
0.010
6
8
8
1 '. bis(chloronier.hyl) ether
0.010
0.010
6
8
8
. bis(2-chloroethyl) ether
0.010
0.010
10
19
19
l',\ 2-chloroethyl vinyl ether
0.010
0.010
6
8
8
20. 2-chloronaphthnlene
0.010
0.010
10
19
18
2i. 2,6,b-trlchlorophenol
0.010
0.010
2
i•
6
22 par.ich loroneta cresol
0.010
0.010
2
U
U
21. chloroform
0.010
0.010
6
8
5
2'i. 2-chlorophenol
0.010
0.010
2
4
i*
2r>. 1,2-dichlorobonzene
0.010
0.010
10
19
19
26. 1 ,3-di ch lorolienzone
0.010
0.010
10
19
19
27. 1,4-dichlorobenzene
0.010
0.010
10
19
19
28. ! ,3'-dichlorobenzIdlne
0.010
0.010
10
19
19
29. 1 .1 -dichlorocthy Ime
0.010
0.010
6
8
8
30. 1,2-trans-dichloroethylene
0.010
0.010
6
8
8
31. 2 .^-iTiciilorophenol
0.010
0.010
2
t.
/i
32. 1,2-dlchloropropane
0.010
0.010
6
8
8
33. 1,3-dichloropropylene
0.010
0.010
6
8
8
i't. 2 ,'i-d itnot hy lphenol
0.010
0.010
2
u
u
35. 2 ,'i-dinitrotoliHYie
0.010
0.010
10
19
19
36. 2 ,6-dini trotolumo
0.010
0.010
10
19
19
37. 1,7-diphenylhydrazine
0.010
0.010
10
19
19
Detected Below
Quantification
Concentration
Detected
Below Treat-
able Concen-
tration
Detected
Above Treat-
able Concen-
tratIon
10
hd
va
w
3
>
w
>
f
G
3
H
•z
G
3
U1
G
m
o
>
W
Q
O
W
u1
w
o
•-3
-------
Table VI — 1 (Continued)
FREQUENCY OF OCCURRENCE OF TOXIC POLLUTANTS
PRIMARY ALUMINUM
RAW WASTEWATER
Analyt Leal
IVtected
Detected
OJ
a\
C^iantlflcat Ion
Treatable
Number of
Number of
Detected Below
Below Treat- Above Treat-
Concentration
Concent ra-
Streams
Samp 1es
CJuanllf lent Ion
able Concen- able Concen-
Pollutant
(mf>/l)(a)
tlon (mn/l)(b)
Analyzed
Analyzed
NO
Concentration
tration Lrat ion
38. ethyIbenzene
0.010
0.010
6
8
8
39. fluoranthene
0.010
0.010
10
19
4
15
40. 4-chlorophenyl phenyl ether
0.010
0.010
10
19
17
1
1
41. 4-bromophenyl phenyl ether
0.010
0.010
10
19
19
42. bls(2-chlorolsopropyl) ether
0.010
0.010
10
19
19
43. bls(2-chloroeLhoxy) methane
0.010
0.010
10
19
19
44. mcthylenp chloride
0.010
0.010
6
8
6
1
1
45. methyl chloride
0.010
0.010
6
8
8
46. methyl bromide
0.010
0.010
6
8
8
47. bromoform
0.010
0.010
6
8
8
48. dichlorobronomethane
0.010
0.010
6
8
8
49. trlchlorofloormnethane
0.010
0.010
6
8
8
50. dichlorodlfluoroinethane
0.010
0.010
6
8
8
51. chlorodibrumoroethane
0.010
0.010
6
8
8
52. hexachlorobutadlene
0.010
0.010
10
19
19
53. hexachlorocyclopentadlene
0.010
0.010
10
19
19
54. Isoplwrone
0.010
0.010
10
19
17
2
55. naphthalene
0.010
0.010
10
19
8
4
7
56. nlLrobenzene
0.010
0.010
10
19
19
57. 2-nltrophenol
0.010
0.010
2
4
4
58. 4-nltrophenol
0.010
0.010
2
4
4
59. 2,4-dlnltrophenol
0.010
0.010
2
4
4
60. 4,6-dlnlt.ro-o-cresol
0.010
0.010
2
4
4
61. N-nltrosodlmethylamlne
0.010
0.010
10
19
19
62. N-nltrosodlphenyLamlne
0.010
0.010
10
19
16
2
1
>3. N-nltrosodl-n-propylamlne
0.010
0.010
10
19
19
64. pentachloropheiiol
0.010
0.010
2
4
4
65. phenol
0.010
0.010
2
4
3
1
66. bls(2-ethyIhexyl) phthalate
0.010
0.010
10
19
2
5
\?
67. butyl benzyl phthalate
0.010
0.010
10
19
15
4
68. di-n-bulyl phthalate
0.010
0.010
10
19
9
7
3
69. dl-n-octyl phthalate
0.010
0.010
10
19
18
1
70. diethyl phthalate
0.010
0.010
10
19
18
1
71. dimethyl phLhalate
0.010
0.010
10
19
19
72. benzo(a)anLliracenc
0.010
0.010
10
19
4
1
14
73. benzo(a)pyrene
0.010
0.010
10
19
6
1
12
74. 3,4-benzofluoranthme
0.010
0.010
10
19
9
9
1
u
V
M
s
>
~<
>
t"1
G
3
M
s:
G
3
w
G
co
o
>
n
CD
o
*1
~<
in
n
o
-------
Table Vl-1 (Continued)
FRF.QUF.NCY OF OCCURRENCE OF TOXIC POLLUTANTS
PRIMARY ALUMINUM
RAW WASTEWATER
U)
Pollutant
Analytical
(^iant Iftear ion
Concent rat Ion
(ny,/l) (a)
TroHtalile Numh(T of Number of
Concent ra- Streams Samples
tlon (ny./l)(b) Analyzed Analyzed
Detected Re low
ND
(^UHIlt I
Coneon
7'j. benzo(k)fluoranthene
0.010
0.010
10
19
9 9
1
76. chryspne
0.010
0.010
10
19
it 1
l'i
11. aci?naplitliylene
0.010
0.010
10
19
13 5
1
78. anthracene (c)
0.010
0.010
10
19
2 5
1 II
79. benzo(n)i i )perylaie
0.010
0.010
10
19
12 1
1 5
80. 1luorene
0.010
0.010
10
19
5 5
9
81. (itHTianthrene (c)
0.010
0.010
10
19
2 5
1 11
82. dllK,nzo(a,h)anthracene
0.010
0.010
10
19
13 1
5
8"). lndo>o( 1 ,2 ,3-cd)pyrfne
0.010
0.010
10
19
15 2
2
8't. py rene
0.010
0.010
10
19
2 1
16
8">. i.ctrnchloroethyl«ie
0.010
0.010
6
8
8
86. toluene
0.010
0.010
6
8
6 2
87. trlcliloroethyImp
0.010
0.010
6
8
7 1
88. vinyl chloride
0.010
0.010
6
8
8
89. altlrin
0.005
0.010
3
3
2 1
90. dleldrln
0.005
0.010
3
3
1 2
91. clilordane
0.005
0.010
3
3
3
92. *.,V-D17T
0.005
0.010
3
3
3
91. -0IH-:
0.005
0.010
3
3
2 1
9U. it,','-DUO
0.005
0.010
3
3
2 1
9"). alpha-endonulfan
0.005
0.010
3
3
2 1
96. beta-endosulfan
0.005
0.010
3
3
2 1
97. endoRulfan sulfate
0.005
0.010
3
3
2 1
98. endrin
0.005
0.010
3
3
2 1
99. ciKJrln aldehyde
0.005
0.010
3
3
3
100. heptachlor
0.005
0.010
3
3
1 2
101. heptachlor epoxide
0.005
0.010
3
3
1 2
102. alpha-RHC
0.005
0.010
3
3
1 2
103. beta-BIIC
0.005
0.010
3
3
1 2
1 'Vi. p;aimta-RIIC
0.005
0.010
3
3
3
10*). delta-WIC
0.005
0.010
3
3
1 2
106. PCH-12U2 (d)
0.005
0.010
3
3
2
1
107. K;R-12Vi (d)
0.005
J
3
2
1
108. PCR-1221 (d)
0.005
3
3
2
1
1.19. K;R-I2")2 (e)
0.005
0.010
3
3
3
liO. HCR-17^8 (e)
0.005
3
3
3
III. PCB-I 260 (e)
0.005
3
3
3
112. PCH-1016 (e)
0.005
3
3
3
teat ion
ration
Otected
Relcw Treat-
able Concen-
tration
Detected
Abcve Treat-
able Concen-
trat ion
hj
JO
M
3
>
JO
K
>
f
G
3
M
G
3
(/)
G
ffl
O
>
w
o
o
w
w
cn
n
-------
Table VI — 1 (Continued)
FREQUENCY OF OCCURRENCE OF TOXIC POLLUTANTS
PRIMARY ALUMINUM
RAW WASTEWATER
Ana lyt ical
Treatable
Detected
Detected
QiianC 11 1 cat ion
Concentra-
Number of
Number of
Detected Below
Below Treat-
Above Treat-
ConcentratIon
r ion
Streams
Samples
t^jant It Icat Ion
able Concen-
able Concen-
Hoilutanl
(ntR/l)(b)
Analyzed
Analyzed
ND
Concentration
tration
tration
113. toxaphene
0.000
0.010
3
3
2
1
114. ant i nwny
0.100
0.47
11
21
7
4
115. arsenic
0.010
0.34
11
21
4
10
7
116. asbestos
10 MKL
10 MFL
1
1
1
117. beryI1ium
0.010
0.20
11
21
9
11
1
lib. cadmum
0.002
0.049
11
21
II
2
8
119. chromium
0.005
0.07
II
21
4
14
3
120. copper
0.009
0.39
11
21
1
16
4
121. cyanide
0.02(f)
1-1 (R)
12
22
2
10
10
—1
172. lead
0.020
0.08
11
21
6
3
12
LO
oo
123. mercury
0.0001
0.036
10
18
15
3
124. nickel
0.005
0.22
11
21
4
6
11
12"j. selenium
0.01
0.20
11
21
7
1
13
126. silver
0.02
0.07
11
21
11
7
3
127. thallium
0.100
0.34
11
21
14
2
5
128. zinc
0.050
0.23
11
21
3
11
7
129. 2 , 3, 7 ,8-tet rach lorodibenzo-
Not analyzed
p-dioxin (TCI)U)
(a) Analytical quant I f leal toil concentration was reported with the data (sec Section V).
(h) Treatable concent rat ions are based orted together.
(f) Analytical quant If leal Ion concentration for KPA Method 335.2, Total Cyanide Methods for Chemical Analysis of Water and Wastes, KHA-600/4-79-020,
March, 1979.
(ft) Rased un cyanide precipitation, llino precipitation, scdimentat Ion, and rmltlmedia filtration. Refer to Section VII - Pilot Scale Trealabi I Ity
Study.
M
s
>
K
>
C
3
M
25
C
3
U)
C
(0
o
>
t-3
W
O
O
vo
K
(/)
W
o
t-3
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - VI
TABLE VI-2
TOXIC POLLUTANTS NEVER DETECTED
2.
acrolein
3.
acrylonitrile
5.
benzidene
6.
carbon tetrachloride
7 .
chloroben2ene.
8.
1,2,4-trichlorobenzene
9.
hexachlorobenzene
10.
1,2-dichloroethane
11.
1,1,1-trichloroethane
12.
hexachloroethane
13.
1,1-dichloroethane
14.
1,1,2-trichloroethane
15.
1,1,2,2-tetrachloroethane
16.
chloroethane
17.
DELETED
18.
bis(2-chloroethyl) ether
19.
2-chloroethyl vinyl ether
21.
2,4,6-trichlorophenol
22.
parachlorometa cresol
24.
2-chlorophenol
25.
1,2-dichlorobenzene
26 .
1,3-dichlorobenzene
27 .
1,4-dichlorobenzene
28.
3,3'-dichlorobenzidiene
29.
1,1-dichloroethylene
30.
1,2-trans -dichloroethylene
31 .
2,4-dichlorophenol
32 .
1,2-dichloropropane
33.
1,3-dichloropropylene
34 .
2,4-dimethylphenol
35.
2,4-dini t rotoluene
36.
2,6-dinitrotoluene
37 .
1,2-diphenylhydraz i ne
38.
ethylbenzene
40 .
4-chlorophenyl phenyl ether
41 .
4-bromophenyl phenyl ether
43 .
bis(2-chloroethoxy) methane
45.
methyl chloride
46 .
methyl bromide
47 .
bromoform
48.
dichlorobromonethane
49.
DELETED
739
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - VI
TABLE VI-2 (Continued)
TOXIC POLLUTANTS NEVER DETECTED
50. DELETED
51. chlorodibromomethane
52. hexachlorobutadiene
53. hexachlorocyclopentadiene
56. nitrobenzene
57. 2-nitrophenol
58. 4-nitrophenol
59. 2,4-dinitrophenol
60. 4,6-dinitro-o-cresol
61. N-nitrosodimethylamine
63. N-nitrosodi-n-propylamine
64. peritachlorophenol
71. dimethyl phthalate
85. tetrachloroethylene
88. vinyl chloride
129. 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)
740
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - VI
TABLE VI-3
TOXIC POLLUTANTS NEVER FOUND ABOVE THEIR
ANALYTICAL QUANTIFICATION LEVEL
54.
isophorone
69.
di-n-octyl phthalate
70.
diethyl phthalate
86.
toluene
87 .
trichloroethylene
89.
aldrin
90.
dieldrin
91.
chlordane
92.
4,4'-DDT
93.
4,4'-DDE
94.
4,4'-DDD
95.
alpha-endosulfan
96.
beta-endosulfan
97 .
endosulfan sulfate
98.
endr in
99.
endrin aldehyde
100.
heptachlor
101.
heptachlor epoxide
102 .
alpha-BHC
103.
beta-BHC
104.
gamma-BHC
105.
delta-BHC
109.
PCB-1232 (a)
110.
PCB-1248 (a)
111.
PC3-1260 (a)
112.
PCB-1016 (a)
113.
toxaphene
Reported together as a combined value.
741
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - VI
TABLE VI-4
TOXIC POLLUTANTS DETECTED IN A SMALL NUMBER OF SOURCES
4.
benzene
20.
2-chloronaphthaIene
23.
chloroform
42 .
bis(2-chloroisopropyl) ether
44 .
methylene chloride
62 .
N-nitrosodiphenylamine
65.
phenol
66 .
bis(2-ethylhexyl) phthalate
67.
butyl benzyl phthalate
68.
di-n-butyl phthalate
74.
3,4-benzofluoranthene
75.
benzo(k)fluoranthene
77.
acenaphthylene
03.
indeno(l,2,3-cd)pyrene
106 .
PCB-1242 (a)
107.
PBC-1254 (a)
108.
PCB-1221 (a)
117.
beryllium
126.
silver
127 .
thallium
(a) Reported together as a combined value.
742
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - VII
SECTION VII
CONTROL AND TREATMENT TECHNOLOGIES
The preceding sections of this supplement discussed the
wastewater sources, flows, and characteristics of the wastewaters
from primary aluminum plants. This section summarizes the
description of these wastewaters, indicates the level of
treatment which is currently practiced in the primary aluminum
subcategory, and describes the treatment options considered by
EPA for this subcategory.
TECHNICAL BASIS OF BPT
As mentioned in Section III, EPA promulgated BPT effluent
limitations guidelines for the primary aluminum smelting
subcategory on April 8, 1974. In order to put the treatment
practices currently in place and the technologies selected for
BAT options into the proper perspective it is necessary to
describe the technologies selected for BPT. The BPT regulations
established by EPA limited the discharge of fluoride and TSS and
required the control of pH. The best practicable control
treatment currently available identified was the treatment of
wet scrubber water and other fluoride-containing effluents
through the precipitation of fluoride, followed by settling of
the precipitate and recycling of the clarified effluent to the
wet scrubbers. Two precipitation technologies, cryolite
precipitation and lime precipitation, were determined to be
effective and it was left to the individual operator to select
the one best suited for his specific application. Recycle of the
clarified effluent was required, but EPA recognized that complete
recycle was not practicable and made an allowance for a bleed
stream to be discharged.
CURRENT CONTROL AND TREATMENT PRACTICES
This section presents a summary of the control and treatment
technologies that are currently applied to each of the sources
generating wastewater in this subcategory. As discussed in
Section V, wastewater associated with the primary aluminum
subcategory is characterized by the presence of the toxic metal
pollutants, cyanide, toxic organics, fluoride, aluminum, oil and
grease, and suspended solids. Generally, these pollutants are
present in each of the waste streams at concentrations above
treatability, so these waste strearr.s are commonly combined for
treatment to reduce the concentrations of these pollutants.
Construction of one wastewater treatment system for combined
treatment, in some instances, combines streams of differing
alkalinity which reduces treatment chemical requirements. Seven
plants ir. this subcategory currently have combined wastewater
treatment systems, eight plants operate lime and settle treatment
on at least a portion of their wastewater. One plant operates a
multimedia filter as an ena-of-pipe polishing step. Four options
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - VII
were considered for BAT, BDT, and pretreatment in this
subcategory, based on combined treatment of these compatible
wastewater streams.
ANODE AND CATHODE PASTE WET AIR POLLUTION CONTROL
Preparing anode paste requires crushing, screening, calcining,
and grinding and mixing of coke and pitch. These are inherently
dusty operations requiring extensive particulate emission
controls. Twenty-two plants preparing paste use dry air
pollution control devices while only four use wet air pollution
control devices. Three plants do not use any emission control.
Wastewaters associated with the wet air pollution control devices
have treatable concentrations of suspended solids. Organic
pollutants such as fluorene, pyrene, and chrysene that are
evolved during calcining of the paste also occur in treatable
concentrations. None of the plants reporting this waste stream
recycle any scrubber water. Two of these plants use chemical
precipitation and sedimentation to treat the wastewater. One
plant uses only sedimentation, while the remaining plant
discharges without treatment.
ANODE BAKE PLANT WET AIR POLLUTION CONTROL
Anode bake plant air emissions are more complex than paste
preparation emissions and reportedly are more difficult
bake plant as cryolite when anode butts are recycled. Dry
electrostatic precipitators (ESP) and baghouses may not
adequately control fluorides since the tars and oils emitted
cause the equipment to be susceptible to arcing and blinding,
respectively, which inhibit the performance of thes2 systems.
Wet control systems, such as wet ESP or scrubbers, are not as
susceptible to problems caused by tars and oils. Fluidized
alumina systems are dry systems which avoid the tar and oil
blinding and arcing problems previously mentioned. Dry systems
are used by 12 out of the 17 plants which control anode baking
emissions. Three plants use only baghouses, three plants use
activated alumina, and two plants use both activated alumina and
baghouses. Of the five plants using wet control systems, four
use wet scrubbers, two use wet ESP, and two use dry ESP preceded
by wet scrubbers.
Wastewater from the wet air pollution control equipment at plants
where anode butts are recycled must be treated for fluorides,
tars, oils, and particulates. If care is taken in the removal of
fused cryolite from the anode butts before reprocessing, fluoride
emissions from the anode bake plant are greatly lowered; hence,
the fluoride concentrations in bake plant scrubber waters would
be minimized. Two of the five plants practice partial recycle of
the scrubber effluent (91 and 99+ percent). Typical treatxent of
this wastewater, practiced at all five plants, consists of alkali
addition and sedimentation for suspended solids and fluoride
744
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - VII
removal.
ANODE AND BRIQUETTE CONTACT COOLING
This wastewater is generated when green anodes and briquettes are
sprayed with water to accelerate their temperature loss and allow
faster handling. Eleven of the 31 plants in the primary aluminum
subcategory reported the use of anode contact cooling and
briquette quenching water. This wastewater contains suspended
solids, fluoride, and organics. One of the four plants reporting
this effluent practices 100 percent recycle, thereby eliminating
its discharge. Another plant utilizes anode cooling water as
off-gas quench water in the bake plant. All water is consumed by
evaporation, thereby eliminating its discharge. Alkali addition
and sedimentation can be used to remove suspended solids and
fluoride. The following treatment schemes are currently in place
in the industry:
1. No treatment - five plants,
2. Settling pond - one plant,
3. Alkali addition and sedimentation - one plant,
4. 100 percent evaporation - two plants,
5. 100 percent reuse in other plant processes - one plant,
6. Cooling tower, retention pond, recycle - one plant.
CATHODE REPROCESSING
Cathodes are reprocessed to recover cryolite by a leaching
operation. The cryolite is then precipitated from the leachate
and reused. The supernatant from the precipitation step or
solids underflow is the cathode reprocessing wastewater. Four
plants generate this wastewater.
As discussed in Section V, wastewater from cathode reprocessing
contains treatable concentrations of suspended solids, fluoride,
and cyanide. Its composition is similar to that of the potline
scrubber effluent, and the treatment techniques used for potline
scrubber water are used to treat the cathode reprocessing
effluent. The pH of the cathode reprocessing wastewater is
extremely alkaline (pH of approximately 11). One plant reported
using alkaline chlorination to treat cyanide prior to discharge.
Three plants use cathode reprocessing water as potline scrubber
liquor make-up.
POTLINE AND POTROOM WET AIR POLLUTION CONTROL
Wet and dry emission control devices are used to collect potline
air emissions that contain particulates, fluorides, hydrocarbons,
and sulfur oxides immediately above the electrolytic cell.
Gaseous fluorides are removed by dry alumina adsorption or wet
scrubbing, while particulate collection is usually performed with
baahouses.
A typical dry potline emission control system includes hoods and
ducts to collect and deliver the gases from the pots to air
745
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - VII
pollution control units (the first is usually a cyclone-type
device to separate coarse particulates), a reactor section in
which the gases are contacted with the alumina, and a fabric
filter. After passing through the fabric filter, the gases are
released to the atmosphere.
Activated alumina dry collection systems allow for the subsequent
return of the alumina and sorbed fluoride compounds to the pots.
Generally high removal efficiencies for both gaseous fluoride
compounds and particulates are obtained (e.g., greater than 99
percent). This dry scrubbing process represents a significant
means of reducing effluent discharges at primary aluminum plants
since it uses no water.
Although many plants have converted from wet to dry primary
scrubbing since 1974, nine plants still practice wet air
pollution control for potline emissions. One plant reporting a
potline scrubber uses 100 percent recycle of this wastewater.
Five other plants report partial recycle ranging from 88 to 99 +
per cent.
Potroom emission control.systems handle larger volumes of air
than potline emissions control systems. Because there is a
larger volume of air from this process, dry scrubbing systems are
very expensive. A treated baghouse contains a limited number of
sites for adsorption; therefore, larger volumes of gas decrease
the life of each filter which in turn increases operating costs.
Consequently, plants have typically used wet scrubbing systems to
control potroom emissions. Seven plants use secondary emission
controls (i.e., potroom emission control) consisting of spray
chambers or packed towers. One plant reported using foam
scrubbers. Six plants with potroom scrubbers reported partial
recycle rates of scrubber water ranging from 42 to 99+ percent.
Water from wet scrubbers will contain fluoride, metals, suspended
solids, and organics in treatable concentrations and is treated
to remove impurities before it is recycled. In the case of
primary potline and secondary potroom wet scrubbers, the fluoride
dissolved in the water is precipitated and settled. This
treatment also reduces the suspended solids and metals content at
the same time.
The method most commonly used to remove the fluoride from wet air
pollution control wastewaters from potlines and potrooms is
precipitation either as cryolite or as calcium fluoride. In the
first case, sodium aluminate (or caustic soda and hydrated
alumina) is added. In the second case, a lime slurry (or calcium
chloride) is used. After precipitation, the slurry is sent to a
thickener. The treatment of wet scrubber liquor to recover
cryolite results in sufficient removal of fluoride to permit
recycle of the treated liquor. The process also recovers the
fluoride in a form which can be returned to the aluminum cell
bach. The value of the recovered cryolite partially offsets the
cost of the treatment process. However, the gradual buildup of
pollutants in the scrubber liquor requires a blowdown, preventing
746
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - VII
total recycle of scrubber liquor. (Recovery of the cryolite is
practiced at four of the nine plants reporting potline scrubbing
and by two of eight plants reporting potroom scrubbers.)
Elevated levels of suspended solids (19 to 54,500 mg/1) are
effectively reduced by the fluoride precipitation and
sedimentation process.
POT REPAIR AND POT SOAKING
Approximately every two to three years the carbon liners of the
electrolytic cells fail and must be replaced. To facilitate
removal, the carbon liners are often soaked in water to make them
soft. Reportedly, some plants use high pressure water jets to
remove the carbon liner.
Data on pot repair and pot soaking wastewater are limited. Two
of the plants reported in Table V-16 (page 688) are known to
reuse pot repair-pot soaking wastewater as potline scrubber
liquor make-up, and one plant reported discharging its wastewater
to cathode reprocessing. Two plants reported using ion-exchange
to reduce cyanide concentrations and lime to precipitate
fluoride. Since each primary aluminum plant must replace the
carbon liners (or cathodes) and very few plants report generating
or discharging this wastewater, it is assumed most plants recycle
and reuse pot soaking wastewater, or use dry removal techniques.
DEGASSING WET AIR POLLUTION CONTROL
The method most commonly used for degassing and refining molten
aluminum is to inject the aluminum with chlorine and other inert
gases. The hydrogen is absorbed into the chlorine bubbles, and
gaseous hydrochloric acid is subsequently produced. Because of
the corrosive nature of the gas stream, it may be necessary to
use wet air pollution control devices instead of dry control
equipment to reduce the pollutant emissions. Three primary
aluminum plants reported using wet air pollution controls for the
degassing operation.
Emphasis has been placed on examining methods for eliminating the
need for wet control devices rather than on methods of treating
the scrubber effluent.
Past emission control efforts have resulted in the development
and successful use of gas mixtures such as chlorine plus an inert
gas, or chlorine, carbon monoxide, and nitrogen. In the case of
mixed gases, gas burners or controlled combustion gas generators
are used to produce a gas of carefully controlled composition.
The foil owing is a list of alternative in-line fluxing and
filtering methods:
1. Flotation with mixtures of chlorine and other gases,
2. Impingement, ar.d
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - VII
3. Counter flow impingement.
Since primary aluminum plants are also often aluminum formers,
degassing is often performed in conjunction with the aluminum
forming demagging operation. This can make the application of
alternative degassing methods more difficult. All of the above
listed degassing alternatives are in commercial use on a regular
basis and may be considered established practice in one or more
producing plants. The viability of each degassing alternative
varies, from plant to plant. As a result, the applicability of
any specific process alternative is determined on an individual
basis.
CASTING CONTACT COOLING
All of the different aluminum casting contact cooling wastewaters
are grouped together for discussion because they differ primarily
in the volume of water used and discharged. With the exception
of oil and grease, the pollutant concentrations in the casting
contact cooling waters are expected to be similar. Oil and
grease concentrations may differ among the wastewaters depending
upon the use of lubrication agents for casting.
Of the 31 primary aluminum plants, 28 reported the use of casting
contact cooling water. Three plants achieved zero discharge
through evaporation, one plant achieved zero discharge through
spray irrigation, and one achieved zero discharge by using the
contact cooling bleed stream as makeup water for the potline
scrubber. The remaining plants discharge the cooling water.
Casting contact cooling water will contain dissolved and
suspended solids and, if a mold lubricant is used, oil and
grease. Control of wastewater from direct contact cooling is
commonly achieved by means of a cooling tower, with recycle of
the water. A bleed stream may be necessary to reduce
concentrations of dissolved and suspended solids, and oil and
grease. Eleven of the 28 plants recycle this wastewater. The
recycle rates ranged from 20 to 99+ percent.
Oil and grease concentrations in the contact cooling effluent
stream may be reduced by the use of oil skimmers. The bleed
stream may also need to be treated for oil and grease and
dissolved and suspended solids. Suspended solids may be removed
simply by sedimentation, while dissolved solids must be
precipitated from solution. Data supplied by the primary
aluminum subcategory indicate that three facilities incorporate
oil skimming into their wastewater treatment plants.
CONTROL AND TREATMENT OPTIONS
The Agency examined four control and treatment technology options
between proposal and promulgation that are applicable to the
primary aluminum subcategory. The options selected for
evaluation represent a combination of in-process flow reduction,
preliminary treatment technologies applicable to individual waste
748
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - VII
streams, and end-of-pipe treatment technologies.
OPTION A
Option A for the primary aluminum subcategory requires treatment
technologies to reduce the discharge of pollutant mass. The
Option A treatment model consists of treatment with lime and
settle (chemical precipitation and sedimentation) applied to all
waste streams and oil skimming. where required. Chemical
precipitation is used to remove metals and fluoride by the
addition of lime followed by gravity sedimentation. Suspended
solids are also removed from the process.
OPTION B
Option B for the primary aluminum subcategory consists of all
treatment requirements of Option A (lime precipitation,
sedimentation, and oil skimming) plus control technologies to
reduce the discharge of wastewater volume and chemical
precipitation with ferrous sulfate to control cyanide from
cathode reprocessing wastewaters. Water recycle and reuse are
the principal control mechanisms for flow reduction.
EPA considered cyanide treatment using chemical oxidation with
chlorine. Although the chlorine oxidation process can be used
effectively for wastewater containing predominantly free cyanides
and easily oxidizable cyanide complexes, the Agency determined
that precipitation with ferrous sulfate is more effective than
chlorine oxidation for the removal of iron-cyanide complexes
which are found in primary aluminum wastewater.
At some plants, cathode reprocessing wastewater is reused in
potline wet air pollution control systems. When this occurs, the
potline scrubber wastewater will exhibit treatable cyanide
concentrations and would require treatment for cyanide in the
same manner as the cathode reprocessing wastewater.
OPTION C
Option C for the primary aluminum subcategory consists of all
control and treatment requirements of Option B (in-process flow
reduction, oil skimming, cyanide precipitation with ferrous
sulfate, lime precipitation, and sedimentation), plus multimedia
filtration technology added at the end of the Option B treatment
scnerr.e. Multimedia filtration is used to remove suspended
solids, including precipitates of metals and fluoride, beyond the
concentration attainable by gravity sedimentation. The filter
suggested is of tie gravity, mixed media type, although other
forms of filters such as rapid sand filters or pressure filters
would also perform satisfactorily. The addition of filters also
provides consistent removal during periods of time in which there
are rapid increases in flows or loadings of pollutants to the
treatment system.
749
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - VII
OPTION E
Option E for the primary aluminum subcategory consists of Option
C (in-process flow reduction, oil skimming, cyanide precipitation
with ferrous sulfate, lime precipitation, sedimentation, and
multimedia filtration) with the addition of activated carbon
adsorption technology at the end of the Option C treatment
scheme. The activated carbon process is used to remove toxic
organic pollutants which remain after lime precipitation,
sedimentation, and filtration.
CONTROL AND TREATMENT OPTIONS REJECTED
Three additional control and treatment options were considered
prior to proposing mass limitations for this subcategory as
discussed below. Activated alumina (fluoride adsorption) and
reverse osmosis were rejected because they are not demonstrated
in the nonferrous metals manufacturing point source category, nor
are they clearly transferable. Pretreatment of certain waste
streams using activated carbon was also eliminated. A pilot
scale treatability study performed by the Agency after proposal
demonstrated that toxic organic pollutants in primary aluminum
wastewaters are substantially removed through lime, settle, and
filter treatment. The findings of this study eliminated further
consideration of activated carbon treatment.
FLUORIDE TREATMENT EFFECTIVENESS ANALYSIS
In settlement agreement negotiation, the Agency re-evaluated the
variability factors for fluoride in the primary aluminum
subcategory based on petitioners claims that the presence of
complex fluoride ions and aluminum salts increase the difficulty
of achieving the limitations promulgated in June 1984. The
Agency has retained the long-term mean but increased the
variability factors for fluoride to the pooled variability
factors computed from data for seven metal pollutants in the
combined metals data base (4.10 and 1.82 for the one day maximum
and the monthly average of daily values variability factors,
respectively). These new treatment effectiveness values for
fluoride are 59.5 mg/1, maximum for any one day and 26.4 mg/1
maximum monthly average of daily values.
TREATMENT EFFECTIVENESS FOR POTLINE SCRUBBER AND CATHODE
REPROCESSING WASTEWATERS
The Agency evaluated industry comments after proposal and made
additional studies of the treatment effectiveness of treatment
technologies applied to potline air pollution control scrubber
wastewater and cathode reprocessing wastewater. These studies,
reported in Section V of this supplement, indicate that the
nature of the wastewater matrix of these wastewaters is such that
treatment effectiveness values other than those displayed in
Table VII-21 of Vol 1 should be used. The Agency has elected to
750
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PRIMARY ALUMINUM SUBCATEGORY SECT - VII
develop mass discharge limitations for these two wastewater
streams when they are uncomingled with any other waters based on
the results of the special treatment studies. These treatment
effectiveness values are summarized in Table VII-1 (page 735).
When these wastewaters are comingled with other waters, the
treatment effectiveness levels of Table VII-21, Vol 1 (page 248)
are used.
Spent potliner leachate may receive the treatment performance
values developed for cathode reprocessing and provided: (a) the
permit writer determines on a case by case basis that the
wastewater matrices of cathode reprocessing and spent potliner
leachate are comparable; and (b) the spent potliner leachate is
not commingled with process or non-process wastewaters other than
cathode reprocessing or potline wet air pollution control
operated in conjunction with cathode reprocessing. Spent potliner
leachate resulting from atmospheric precipitation runoff is
considered a site specific non-scope wastewater stream by the
Agency and for this reason specific limitations are not provided
in this regulation.
BENZO(A)PYRENE TREATMENT EFFECTIVENESS ANALYSIS
In settlement negotiations after promulgation, the Agency revised
its statistical analysis of benzo(a)pyrene data to develop one
day maximum and monthly average treatment effectiveness
concentrations as a basis for calculating mass discharge limits.
The recalculated treatment effectiveness concentrations are
0.0337 mg/1 maximum for any one day and 0.0156 mg/1 maximum
monthly average of daily values. The Agency also restricted the
discharge allowance for benzo(a)pyrene to those streams which
actually contain this pollutant.
751
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PRIMARY ALUMINUM SUBCATEGORY SECT - VII
TABLE VII-1
TREATMENT EFFECTIVENESS FOR SELECTED BUILDING BLOCKS
Lime Settle and Filter Technology
(rr.g/1)
One-day
10-day
30-day
Pollutant
Mean
Maximum
Average
Average
Acenaphthene
0.010
0.0337
0 .0156
NC
Benzo(a)anthracene
0.023
0.0775
0.036
NC
*Benzo(a)pyrene
0.010
0.0337
0.0156
NC
3,4-Benzofluoranthene
0.010
0.0337
0.0156
NC
Benzo(k)fluoranthene
0.010
0.0337
0.0156
NC
Benzo(ghi)perylene
0.010
0.0337
0.0156
NC
Chrysene
0.023
0 . 075
0.036
NC
Dibenzo(a,h)anthracene
0.010
0.0337
0.0156
NC
Floranthene
0.114
0 . 384
0.178
NC
Pyrene
0 . 079
0. 266
0 .123
NC
~Antimony
2. 99
12.0
5.4
NC
*Cyanide
1 . 1
4.5
2.0
NC
*Nickel
0.57
2.3
1.0
NC
*Alumi num
1.9
7.8
3.5
NC
*Fluor ide
206
840
380
NC
*TSS
15
61. 5
27.3
NC
* = Regulated Pollutant
NC = Not calculated
NOTE: These values may be used only for calculating allowances
for cathode reprocessing and potline wet air pollution control
wastewaters when they are not commingled with any other
wastewaters.
752
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PRIMARY ALUMINUM SUBCATEGORY SECT - VIII
SECTION VIII
COSTS, ENERGY, AND NONWATER QUALITY ASPECTS
This section describes the method used to develop the estimated
costs associated with the control and treatment technologies
discussed in Section VII for wastewaters from primary aluminum
plants. The energy requirements of the considered options as
well as solid waste and air pollution aspects are also discussed
in this section.
Section VI indicated that significant pollutants or pollutant
parameters in the primary aluminum subcategory are benzo(a)
pyrene, aluminum, antimony, nickel, cyanide, fluoride, TSS, pH,
and oil and grease. Metals and fluorides are most economically
removed by chemical precipitation, sedimentation and filtration.
These technologies also remove toxic polynuclear aromatic
hydrocarbons. Cyanide concentrations can be reduced by chemical
precipitation with ferrous sulfate or by ion-exchange. Activated
carbon is an effective treatment for removing organics.
LEVELS OF TREATMENT CONSIDERED
As discussed in Section VII, four control and treatment options
were considered for treating wastewater from the primary aluminum
subcategory. Cost estimates were developed for each of these
control and treatment options. Cost estimates, in the form of
annual cost curves, have been developed for each of these control
and treatment options, and they are presented in Section VIII of
the General Development Document. The control and treatment
options are presented in Figures X-l through X-4 (pages 808
811) .
OPTION A
Option A for the primary aluminum subcategory consists of lime
precipitation and sedimentation applied to combined wastewater
streams. Oil skimming is added as a preliminary treatment step
to remove oil and grease from all waste streams except stationary
and shot casting, potline SO2 wet air pollution control, and
degassing wet air pollution control.
OPTION B
Option B for the primary aluminum subcategory consists of all
treatment requirements of Option A (lime precipitation,
sedimentation, and oil skimming) plus control technologies to
reduce the discharge of wastewater volume and chemical
precipitation with ferrous sulfate to control cyanide from
cathode reprocessing wastewaters. Water recycle and reuse are
the principal control mechanisms of flow reduction. Flow
reduction measures consist of recycle of contact cooling water
through cooling towers and recycle of wet air pollution
753
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PRIMARY ALUMINUM SUBCATEGORY SECT - VIII
control wastewater through holding tanks.
OPTION C
Option C consists of Option B (cyanide precipitation preliminary
treatment, lime precipitation, sedimentation, oil skimming and
in-process flow redaction) with the addition of multimedia
filtration added to the end of the Option B treatment scheme.
OPTION E
Option E consists
oil skimming,
filtration) with
technology at the
Cost Methodology
of Option C (lime
in-process flow
the addition of
end of the Option
precipitation, sedimentation,
reduction, and multimedia
activated carbon adsorption
C treatment scheme.
A detailed
compliance
costs have
The total
regulat ion
discussion of the methodology used to develop the
costs has been presented. Plant-by-plant compliance
been estimated for the primary aluminum subcategory,
costs for the final primary aluminum subcategory
are presented in Table VIII-1 (page 757).
The major general assumptions used to develop compliance costs
have been presented. Each subcategory contains a unique set of
waste streams requiring certain subcategory-specific assumptions
to develop compliance costs. Six major assumptions applicable
specifically to the primary aluminum subcaategory are discussed
briefly below.
(1) Compliance costs for oil-water separation, flow reduc-
tion via cooling towers, and lime and settle are neces-
sary to meet the previously promulgated BPT regulation
for certain waste streams. These costs are not
included in the current compliance costs if the treat-
ment is in place and of sufficient capacity. If
additional capacity is required to treat waste streams
not considered in the promulgated BPT regulation, the
cost for this capacity is included in the compliance
cost estimate.
(2) In the consideration of activated carbon adsorption as
an end-of-pipe technology, each plant is analyzed to
determine whether separate or combined treatment cf the
organic bearing and organic free waste streams is
economically justified. The least costly configuration
is then used to estimate compliance costs.
(3) Sludge generated by lime and settle treatment is
assumed a hazardous waste when polynuclear aronatics
are removed.
(4) Cyanide precipitation is included as a preliminary
treatment step on cyanide-bearing wastewaters only.
754
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PRIMARY ALUMINUM SUBCATEGORY SECT - VIII
These waters originate only in cathode reprocessing
facilities used by four plants. Hazardous waste dis-
posal costs were included for the sludges generated by
cyanide precipitation.
(5) Capital and annual costs for plants discharging in both
the primary and secondary aluminum subcategories are
based on a combined treatment system and were appor-
tioned to each subcategory on a flow-weighted basis.
(6) Capital and annual costs for plants discharging in the
primary aluminum subcategory and another point source
category are based on separate treatment systems since
the respective regulations are based on different tech-
nologies and control different pollutants. Segregation
costs are included to separate the wastewaters.
NONWATER QUALITY ASPECTS
Nonwater quality impacts specific to the primary aluminum
subcategory, including energy requirements, solid waste and air
pollution are discussed below.
ENERGY REQUIREMENTS
The methodology used for determining the energy requirements for
the various alternatives is discussed in Section VIII of the
General Development Document. Option C, which includes
filtration, is estimated to consume five percent more energy than
the promulgated BPT technology, while activated carbon could
increase energy consumption by approximately 50 percent over BPT.
Option C in a typical plant represents approximately 0.2 percent
of the total plant electrical requirements. Therefore, it is
concluded this regulation will have negligible effects on energy
consumpt ion.
SOLID WASTE
Sludges associated with the primary aluminum subcategory will
necessarily contain toxic quantities (and concentrations) of
toxic netal pollutants. Wastes generated by primary smelters and
refiners are currently exempt from regulation by Act of Congress
(Resource Conservation and Recovery Act (RCRA)), Section 3001(b),
as presently interpreted by the Agency. Consequently, sludges
generated from treating industries' wastewater are not presently
subject to regulation as hazardous wastes.
If these wastes should eventually be identified or are listed as
hazardous, they will come within the scope of RCRA's "cradle to
grave" hazardous waste management program, requiring regulation
from the point of generation to point of final disposition. EPA's
generator standards would require generators of hazardous
nonferrous metals nar.uf actur ing wastes to meet conta i ner i zat ion,
labeling, record keeping, and reporting requirements; if plants
dispose of hazardous wastes off-site, they would have to prepare
755
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PRIMARY ALUMINUM SUBCATEGORY
SECT
- VIII
a manifest which would track the movement of the wastes from the
generator's premises to a permitted off-site treatment, storage,
or disposal facility. See 40 CFR 262.20 45 FR 33142 (May 19,
1980), as amended at 45 FR 86973 (December 31, 1980). The
transporter regulations require transporters of hazardous wastes
to comply with the manifest system to assure that the wastes are
delivered to a permitted facility. See 40 CFR 263.20 45 FR 33151
(May 19, 1980), as amended at 45 FR 86973 (December 31, 1980).
Finally, RCRA regulations establish standards for hazardous waste
treatment, storage, and disposal facilities allowed to receive
such wastes. See 40 CFR Part 464 46 FR 2802 (January 12, 1981),
47 FR 32274 (July-26, 1982).
Even if these wastes are not identified as hazardous, they still
must be disposed of in compliance with the Subtitle D open
dumping standards, implementing 4004 of RCRA. See 44 FR 53438
(September 13, 1979).
Pilot-scale work performed by the Agency since proposal
demonstrated that toxic polynuclear aromatic hydrocarbon
pollutants found in primary aluminum wastewaters are removable
using lime, settle, and filter technology. As a result, the
Agency believes lime sludge from this subcategory will be toxic
due to the presence of these organic contaminants. In addition,
sludges generated during cyanide precipitation are expected to be
hazardous under RCRA. Consequently, in developing plant-by-plant
compliance costs for the primary aluminum subcategory, the Agency
considered the sludges generated as hazardous. The costs of
hazardous waste disposal were considered in the economic
analysis, and they were determined to be economically achievable.
(This is a conservative assumption since these sludges are
presently subject to a statutory and regulatory exemption from
hazardous waste status). It is estimated that Options B and C
will generate approximately 730,000 tons/yr of waste sludge as 20
percent solids. Multimedia filtration technology will not
generate any significant amount of sludge over that resulting
from lime precipitation and sedimentation.
AIR POLLUTION
There is no reason to believe that any additional air pollution
will result from implementation of cyanide precipitation, lime
precipitation, sedimentation, filtration, reverse osmosis, and
carbon adsorption. These technologies transfer pollutants to
solid waste and do not involve air stripping or any other
physical process likely to transfer pollutants to air. In those
plants using lubricants for casting, there may be organics
present in drift from cooling towers along with some particulate
matter used to recycle casting contact cooling water. However,
the Agency believes that the amount of organic constituents and
particulate matter in the drift would not be significant.
756
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PRIMARY ALUMINUM SUBCATEGORY SECT - VIII
TABLE VIII-1
COST OF COMPLIANCE FOR THE PRIMARY ALUMINUM SUBCATEGORY
DIRECT DISCHARGERS
(March 1982 Dollars, Millions)
Proposal Cost Promulgation Cost
Opt ion
Capital
Annual
Capital
Annual
A
11.1
5.3
7.5
7.9
B
33.9
21. 2
14.5
9.8
C
38. 3
24.5
16.0
10.5
D
47.4*
24 . 4*
26.2**
14.7**
* Activated carbon adsorption as a preliminary treatment.
** End-of-pipe carbon adsorption.
-------
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - IX
SECTION IX
BEST PRACTICABLE TECHNOLOGY CURRENTLY AVAILABLE
EPA promulgated BPT limitations for the primary aluminum
subcategory on April 8, 1974 as Subpart B of 40 CFR Part 421.
Pollutants regulated by these limitations were fluoride, TSS, and
pH. Unlike the current rulemaking, the BPT limitations were
developed for the entire aluminum smelting process, not on the
basis of individual wastewater streams. EPA is not promulgating
any modifications to these limitations.
The following limitations establish the quantity of pollutants or
pollutant properties, which may be discharged by a point source
after application of the best practicable control technology
currently available:
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - kg/kkg of product
English Units - lbs/1,000 lbs of product
Fluoride
Total Suspended Solids
pH
Within the range of 6 to 9
at all times
2.0
3.0
1.0
1.5
759
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7 tsO
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - X
SECTION X
BEST AVAILABLE TECHNOLOGY ECONOMICALLY ACHIEVABLE
The effluent limitations are based on the best control and
treatment technology used by a specific point source within the
industrial category or subcategory, or by another category where
it is readily transferable. Emphasis is placed on additional
treatment techniques applied at the end of the treatment systems
currently used for BPT, as well as reduction of the amount of
water used and discharged, process control, and treatment
technology optimization.
The factors considered in assessing best available technology
economically achievable (BAT) include the age of equipment and
facilities involved, the process used, process changes, nonwater
quality environmental impacts (including energy requirements),
and the costs of application of such technology (Section 304(b)
(2)(B) of the Clean Water Act). BAT represents the best
available technology economically achievable at plants of various
ages, sizes, processes, or other characteristics. Where the
Agency has found the existing performance to be uniformly
inadequate, BAT may be transferred from a different subcategory
or category. BAT may include feasible process changes or
internal controls, even when not in common industry practice.
The statutory assessment of BAT considers costs, but does not
require a balancing of costs against effluent reduction benefits
(see Weyerhaueser vs Costle, 590 F. 2d 1011 (D.C. Cir. 1978)).
However, in assessing the proposed BAT, the Agency has given
substantial weight to the economic achievability of the
technology.
TECHNICAL APPROACH TO BAT
In pursuing this second round of effluent limitations and
standards, the Agency reviewed a wide range of technology options
and evaluated the available possibilities to ensure that the most
effective and beneficial technologies were used as the basis of
BAT. To accomplish this, the Agency examined four technology
alternatives prior to promulgating mass limitations, which could
be applied to the primary aluminum subcategory as BAT options and
which would represent substantial progress toward reduction of
pollutant discharges above and beyond progress achieved by BPT.
In summary, the treatment technologies considered for BAT are
presented below:
Option A (Figure X-l, page 808) is based on
o Preliminary treatment with oil skimming (where required)
o Chemical precipitation and sedimentation
761
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PRIMARY ALUMINUM SUBCATEGORY SECT - X
Option B (Figure X-2, page 809) is based on
o Preliminary treatment with oil skimming (where required)
o Preliminary treatment of cathode reprocessing wastewater
with ferrous sulfate precipitation
o Chemical precipitation and sedimentation
o In-process flow reduction of casting contact cooling
water and scrubber liquor resulting from anode paste
plants, anode bake plants, potlines, and potrooms'
Option C (Figure X-3, page 810) is based on
o Preliminary treatment with oil skimming (where required)
o Preliminary treatment of cathode reprocessing wastewater
with ferrous sulfate precipitation
o Chemical precipitation and sedimentation
o In-process flow reduction of casting contact cooling
water and scrubber liquor resulting from anode paste
plants, anode bake plants, potlines, and potrooms
o Multimedia filtration
Option E (Figure X-4, page 811) is based on
o Preliminary treatment with oil skimming (where required)
o Preliminary treatment of cathode reprocessing wastewater
with ferrous sulfate precipitation
o Chemical precipitation and sedimentation
o In-process flow reduction of casting contact cooling
water and scrubber liquor resulting from anode paste
plants, anode bake plants, potlines, and potrooms
o Multimedia filtration
o Activated carbon adsorption for toxic organic removal
The four options examined for BAT are discussed in greater detail
on the following pages. The first option considered (Option A)
is analogous to the BPT treatment which was presented in the
previous section.
OPTION A
Option A for the primary aluminum subcategory is equivalent to
the treatment technology that is the basis of promulgated BPT
effluent limitations. The Option A treatment scheme consists of
preliminary treatment of casting contact cooling water by oil
skimming and chemical precipitation and sedimentation applied to
the combined wastewater discharges as reported in the data
collection portfolios. Although oil and grease is a conventional
pollutant, oil skimming is needed for BAT to ensure proper metals
removal. Oil and grease interferes with the chemical addition
and mixing required for chemical precipitaticn treatment.
Chemical precipitation is used to remove metals, tcxic organics,
and fluoride by the addition of lime followed by gravity
sedimentation. Suspended solids are also removed from the
process .
762
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PRIMARY ALUMINUM SUBCATEGORY SECT - X
OPTION B
Option B for the primary aluminum subcategory achieves lower
pollutant discharge by building upon the Option A treatment
technology of oil skimming, chemical precipitation, and
sedimentation (see Figure X-2, page 783). Option B uses
preliminary cyanide precipitation technology to reduce cyanide
concentrations and flow reduction measures to reduce the quantity
of pollutants discharged.
Cyanide precipitation, based on ferrous sulfate addition, was
applied only to wastewater generated from cathode reprocessing
and potline scrubber liquor when cathode reprocessing was
performed on-site. At some plants, cathode reprocessing
wastewater is reused in potline wet air pollution control
systems. When this occurs, the potline scrubber wastewater may
exhibit treatable cyanide concentrations and would require
treatment for cyanide in the same manner as the cathode
reprocessing wastewater. Ion exchange has been demonstrated on a
pilot scale in the primary aluminum industry. Performance values
obtained through ion-exchange are very similar to those of the
Agency's pilot scale treatability study using ferrous sulfate.
Alkaline chlorination of cyanide is demonstrated at one primary
aluminum plant.
Flow reduction measures, including in-process changes, result in
the elimination of some wastewater streams and the concentration
of pollutants in other effluents. As explained in Section VII of
the General Development Document, treatment of a more
concentrated effluent allows achievement of a greater net
pollutant removal and introduces the possible economic benefits
associated with treating a lower volume of wastewater. Methods
used in Option B to reduce process wastewater generation and
discharge rates are discussed on the following page.
Recycle of Anode and Casting Contact Cooling Water Through
Cooling Towers
The cooling and recycle of contact cooling water is practiced by
22 of the 31 plants reporting this wastewater. The function of
contact cooling water is to quickly remove heat from the newly
formed anode or cast aluminum. Therefore, the principal
requirements of the water are that it be cool and not contain
dissolved solids at a concentration that would cause water marks
or other surface imperfections. There is sufficient experience
withir. the nonferrous metals manufacturing category with contact
cooling wastewater to assure the success of this technology using
cooling towers or heat exchangers (refer to Section VII cf the
General Development Document). Although one plant reported it
did not discharge any anode quench water by reason of 100 percent
recycle, a blowdown or periodic cleaning is needed to prevent a
buildup cf dissolved and suspended solids. (EPA has determined
that a blcwdown of 10 percent of the water applied in a process
is adequa te. )
763
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PRIMARY ALUMINUM SUBCATEGORY SECT - X
Recycle of Water Used in Wet Air Pollution Control
There are. six wastewater sources associated with wet air
pollution control which are regulated under these effluent
limitations:
1. Anode paste plant,
2. Anode bake plant/
3. Potline,
4. Potline SO2,
5. Potroom, and
6. Degassing.
Table X-l (page 782) presents the number of plants reporting
wastewater use with these sources, the number of plants
practicing recycle of scrubber liquor, and the range of recycle.
The water scrubs particulate matter and fumes from the emissions,
requiring a blowdown or periodic cleaning of scrubber liquor to
prevent the buildup of dissolved and suspended solids.
OPTION C
Option C for the primary aluminum subcategory builds upon Option
B by adding multimedia filtration technology to the end of the
in-process flow reduction, lime precipitation, sedimentation, oil
skimming, and cyanide precipitation with ferrous sulfate,
considered for Option B. A schematic of this treatment
technology is presented in Figure X-3 (page 784) Multimedia
filtration is used to remove suspended solids, including
precipitates of metals and fluoride, beyond the concentration
attainable by gravity sedimentation. The filter suggested is of
the gravity, mixed media type, although other forms of filters,
such as rapid sand filters or pressure filters, would also
perform satisfactorily.
OPTION E
Option E for the primary aluminum subcategory consists of in-
process flow reduction, lime precipitation, sedimentation, oil
skimming, cyanide precipitation with ferrous sulfate, and
multimedia filtration, with the addition of activated carbon
adsorption technology. The activated carbon process is used to
increase the removal of toxic organics after lime precipitation,
sedimentation, and filtration.
INDUSTRY COST AND POLLUTANT REMOVAL ESTIMATES
As one means of evaluating each technology option, EPA developed
estimates of the pollutant reduction and the compliance costs
associated with each option. The methodologies are described on
the following page.
POLLUTANT REMOVAL ESTIMATES
764
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PRIMARY ALUMINUM SUBCATEGORY SECT - X
A complete description of the methodology used to calculate the
estimated pollutant reduction achieved by the application of the
various treatment options is presented in Section X of the
General Development Document. The data used for estimating
pollutant removals are the same as those used to revise the
compliance costs.
Sampling data collected during the field sampling program were
used to characterize the major waste streams considered for
regulation. At each sampled facility, the sampling data were
production normalized for each unit operation (i.e., mass of
pollutant generated per mass of product manufactured). This
value, referred to as the raw waste, was used to estimate
the mass of toxic pollutants generated within the primary
aluminum subcategory. By multiplying the total industry
production for a unit operation times the corresponding raw waste
value, the mass of pollutant generated for that unit operation
was estimated.
The volume of wastewater discharged after the application of each
treatment option was estimated for each operation at each plant
by comparing the actual discharge to the regulatory flow. The
smaller of the two values was selected and summed with the other
plant flows. The mass of pollutant discharged was then estimated
by multiplying the achievable concentration values attainable by
the option (mg/1) by the estimated volume of process wastewater
discharged by the subcategory. The mass of pollutant removed is
the difference between the estimated mass of pollutant generated
within the subcategory and the mass of pollutant discharged after
application of the treatment option.
The pollutant removal estimates for the direct dischargers in the
primary aluminum subcategory are presented in Tables X-2 (page
783) through X-5 (page 786). Table X-2 shows the removals for
the toxic organic pollutants. For inorganic pollutants, removal
estimates were determined based on the long-term achievable
concentration values from either the combined metals data base
(CMDB) or an alternate data base developed from the pilot-scale
treatability study (see Section VII). Treatment performance data
gathered during the pilot-scale study demonstrated that plants
operating cathode reprocessing operations and using the
wastewater as makeup for potline scrubber liquor cannot achieve
the performance values proposed for antimony, nickel, aluminum,
fluoride, and total suspended solids. Therefore, alternate
treatment performance values from the study (Table VII-1, page
752) were used to estimate pollutant removals for those primary
aluminum plants that operate cathode reprocessing and commingle
the resulting wastewater with potline scrubber liquor. (The
treatment performance is discussed in greater detail below.)
Pollutant removal estimates for plants that do not commingle
cathode reprocessing wastewater and potline scrubber liquor were
calculated using the CMDB based treatment effectiveness values in
Table VII-21 (Vol-1 page 248). Tables X-3 and X-4 present the
inorganic pollutant removal estimates using the CMDB based
765
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PRIMARY ALUMINUM SUBCATEGORY SECT - X
treatment effectiveness and the alternate treatment effectiveness
values in Table VII-1, respectively. Inorganic pollutant removal
totals for all direct dischargers are presented in Table X-5.
COMPLIANCE COSTS
Compliance costs presented at proposal were estimated using cost
curves, which related the total costs associated with
installation and operation of wastewater treatment technologies
to plant process wastewater discharge. EPA applied these curves
on a per plant basis, a plant's costs—both capital, and
operating and maintenance—being determined by what treatment it
has in place and by its individual process wastewater discharge
(from dcp). The final step was to annualize the capital costs,
and to sum the annualized capital costs, and the operating and
maintenance costs, yielding the cost of compliance for the
subcategory. Since proposal, the cost estimation methodology was
changed as discussed in Section VIII of this document. A design
model and plant specific information were used to size a
wastewater treatment system for each discharging facility. After
completion of the design, capital and annual costs were estimated
for each unit of the wastewater treatment system. Capital costs
were developed from vendor quotes and annual costs were developed
from literature. The revised compliance costs are presented in
Table VIII-1 (page 757).
BAT OPTION SELECTION
EPA's proposed BAT was based on lime, settle, and filter
technology and flow reduction, with preliminary treatment for
organics and cyanide using activated carbon and ferrous sulfate
precipitation, respectively. Numerous comments were received on
the proposed technology stating, among other things, that the
Agency did not account for the removal of toxic organics in lime
and settle treatment. The transfer of cyanide precipitation and
associated performance values was also contested as unachievable
on primary aluminum wastewaters. The Agency performed pilot-
scale work on potline scrubber blowdown and cathode reprocessing
wastewater at a primary aluminum facility following proposal (see
Sections V and VII). Analytical data gathered during the study
indicate toxic organic pollutants present in primary aluminum
wastewaters are controllable through lime, settle, and multimedia
filtration treatment technology. The toxic organics, present as
polynuclear aromatic hydrocarbons, are only slightly soluble in
water, and thus are treatable using sedimentation and filtration
techniques. Removals by this technology exceed 99 percent of all
toxic organics present. In addition, the most toxic of the
polynuclear aromatic hydrocarbons, including the carcinogen
benzo(a)pyrer.e, are removed to the limit of quantification by
this technology. For these reasons, the Agency does not believe
it is warranted to include the use of activated carbon to remove
the small amounts of these less toxic polynuclear aromatic
hydrocarbons remaining after application of lime, settle, and
filtration technology. At-the-source limitations for toxic
organic pollutants are not appropriate because toxic organics are
766
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PRIMARY ALUMINUM SUBCATEGORY SECT - X
effectively controlled with lime, settle, and filter treatment.
Thus, the promulgated BAT mass limitations for the primary
aluminum subcategory are based on end-of-pipe lime precipitation,
sedimentation, and multimedia filtration. Preliminary treatment
of cyanide is based on cyanide precipitation. Treatment
effectiveness values for toxic organic pollutants and for certain
toxic metals (Table VII-1) are based on data from the Agency's
pilot plant study. They apply to potline wet scrubber and cathode
reprocessing wastewaters provided these wastewaters are not
commingled with any other waters (see below). In-process flow
reduction of scrubber liquors and contact cooling water through
recycle is also included.
Data gathered through specific data requests show cathode
reprocessing wastewaters are normally used as potline scrubber
liquor make-up. An at-the-source limit for cyanide was
considered to prevent dilution of potline scrubber liquor or
cathode reprocessing as a means of compliance. An at-the-source
limit would be appropriate if there were a risk that cyanide
could be diluted to below levels detectable at the end of the
pipe as a result of mixing with wastewaters that do not contain
cyanide. This is not likely to occur because the waste streams
containing cyanide, cathode reprocessing wastewater, and potline
scrubber wastewater have very high flows. These streams would
have to be diluted at roughly a 100 to one ratio for cyanide to
be undetected, an unlikely result. Permit writers should
investigate, however, whether this degree of dilution might occur
at an individual plant (for example, if storm water is being
centrally treated), in which case an at-the-source limit would be
needed to ensure treatment and removal of cyanide.
The final regulation states that only the potline wet scrubber
and cathode reprocessing building blocks receive a cyanide mass
limitation. This effectively precludes dilution because it does
not make economic sense for a plant to treat its entire flow when
it can pretreat these cyanide-containing streams. (The Agency
thus developed compliance costs based on cyanide pretreatment.)
In addition, a mass allowance is provided for cathode
reprocessing only if this operation is not conducted in
conjunction with potline wet scrubbing. Where cathode
reprocessing is operated along with wet potline scrubbing, an
allowance is provided only for the potline scrubber because only
a single flow is associated with both operations. In essence,
the flow from potline scrubbing is routed to the cathode
reprocessing operation for fluoride recovery, and then routed
back to the potline where a blowdown is discharged. There is no
independent flow from cathode reprocessing.
FINAL AMENDMENTS TO THE REGULATION
For the Primary Aluminum Subcategory, EPA promulgated final
amendments on July 7, 1987 (52 FR 25552) to the regulation
concerning four topics, which are briefly described here.
767
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PRIMARY ALUMINUM SUBCATEGORY SECT - X
EPA amended the BAT limitations and NSPS and PSNS Cor
benzo(a)pyrene in two manners: first, to incorporate variability
factors into the daily maximum and monthly average limitations;
and second, to only provide discharge allowances for
benzo(a)pyrene to those processes which generate this substance.
Further, EPA provided clarification on 2 items pertaining to
regulation of benzo(a)pyrene.
EPA amended the BAT limitations and NSPS and PSNS for fluoride to
be based upon the pooled variability factors calculated from data
for seven metal pollutants in the CMDB, instead of the
variability factors from the Electrical & Electronic Components
Phase II regulation.
EPA provided brief guidance on the treatment values that permit
writers may provide for spent potliner leachate, even though EPA
considers spent potliner leachate to be non-process and therefore
a non-scope flow.
EPA has amended the NSPS pH standards for direct chill casting
contact cooling water to a range of 6.0 to 10.0 standard units at
all times.
TREATMENT PERFORMANCE
Overall treatment performance for the cathode reprocessing waste
stream, as well as treatment performance values for three
specific pollutants, namely cyanide, benzo(a)pyrene and fluoride,
are discussed here with respect to their special circumstances in
the primary aluminum subcategory.
Treatment performance data gathered during the pilot-scale study
demonstrated that plants operating cathode reprocessing
operations and using the wastewater as makeup for potline
scrubber liquor cannot achieve the performance values proposed
for antimony, nickel, aluminum, fluoride, and total suspended
solids. The Agency believes this is due to the matrix differences
resulting from cathode reprocessing. The cathode reprocessing
wastewater, and subsequently the potline scrubber liquor, contain
dissolved solids levels in the five to six percent range.
Therefore, the Agency is promulgating separate mass limitations
for those primary aluminum plants that operate cathode
reprocessing and commingle resulting wastewater with potline
scrubber liquor. However, to receive these alternate limitations
the plant may not dilute potline scrubber liquor blowdown or
cathode reprocessing wastewater with any process or nonprocess
wastewater source. If the potline scrubber blowdown is diluted
with other wastewaters, the Agency believes the complexity of the
matrix decreases and thus the concentrations of the combined
metals data base (as well as the transferred antimony
concentration) should be achieved.
In fact, a statistical analysis of untreated wastewater data
shows primary aluminum wastewater to be significantly less
contaminated than wastewater from the plants in the combined
768
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PRIMARY ALUMINUM SUBCATEGORY SECT - X
metals data base.
The variability factors used to determine the mass limitations
for the alternate potline scrubber blowdown and cathode
reprocessing are transferred from the combined metals data base.
The CMDB contains more data points than the pilot-scale study and
thus is a better source for determining variability for lime and
settle treatment.
While not considered a process wastewater stream, EPA has
provided guidance to permit writing authorities that spent
potliner leachate, resulting from either the stockpiling or the
landfilling of spent potliners, may also receive the alternate
treatment performance values developed for cathode reprocessing
or potline scrubber liquor commingled with cathode reprocessing
wastewaters. This guidance is appropriate if the permit writer
determines on a case-by-case basis that the wastewater matrices
of cathode reprocessing and spent potliner leachate are
comparable and the spent potliner leachate is not commingled with
process or nonprocess wastewaters other than cathode reprocessing
or potline wet air pollution control operated in conjunction with
cathode reprocessing.
The Agency's pilot-scale treatment performance studies also
revealed performance limits for cyanide precipitation are not
transferable from coil coating to primary aluminum wastewater.
The Agency believes the cathode reprocessing operations discharge
much higher concentrations of cyanide than observed in coil
coating and impair treatment by also discharging extremely high
dissolved solids concentrations (five to six percent) that
interfere with precipitation chemistry. Therefore, treatment
effectiveness is based on the Agency's pilot study of these
wastewaters. This mean was also shown, in data submitted by a
primary aluminum facility, to be achievable by ion exchange
technology applied to cyanide-contaminated groundwater. In
developing variability factors for cyanide precipitation
technology, the mean variability from the combined metals data
base is used because only two data points were generated by the
treatability study.
The Agency has re-evaluated the treatment performance for
benzo(a)pyrene and has concluded that there is some variability
in treatment of this compound, and that, in addition, the model
treatment technology, lime, settle and filter also has some
associated operating variability. As such, EPA has changed the
benzo(a)pyrer.e effluent limitations and standards by increasing
the daily maximum from 0.010 mg/1 to 0.0337 mg/1 and by adding a
monthly maximum average of 0.0156 mg/1. These limitations were
determined on the basis of a statistical analysis of data on the
treatability of benzo(a)pyrene obtained in the pilot study
referenced above.
As a result of these changes, the allowances for benzo(a)pyrene
are only applicable to those processes that generate it.
Therefore, no discharge allowance will be provided for
769
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PRIMARY ALUMINUM SUBCATEGORY SECT - X
benzo(a)pyrene in the degreasing wet air pollution control,
direct chill casting contact cooling and continuous rod casting
contact cooling building blocks.
The clarification that EPA has provided is twofold: the rule
does not mandate at-the-source limitations for benzo(a)pyrene,
and analytical values at or below the detection limit for any
EPA-approved analytical method will be counted as zeroes for
purposes of determining compliance.
The Agency has re-evaluated lime and settle technology
performance for fluoride removal. The proposed treatment
performance for fluoride was transferred from the electrical and
electronic component manufacturing (phase II) lime and settle
mean performance. Because of the presence of complex fluoride
ions and aluminum salts in the primary aluminum subcategory
wastewaters, petitioners to the promulgated regulation claimed
that the fluoride limitations are not achievable. EPA is thus
retaining the long-term mean but increasing the variability
factors for fluoride (49 FR 8751, 8757). The revised promulgated
limitations are based on the pooled variability factors
calculated from data for seven metal pollutants in the combined
metals data base. The variability factors used are 4.10 and 1.82
for daily and monthly variability factors, respectively, as
opposed to the values 2.40 and 1.3 which were used for the March
1984 promulgation. These new variability factors change the one-
day and monthly treatment effectiveness values to those shown in
Table VII-21 (page 248, Vol-l).For the primary aluminum
subcategory, the one-day and monthly treatment effectiveness for
fluoride become 59.5 and 26.4 mg/1, respectively. The Agency
believes that the variability associated with the metals data
will more accurately represent the fluoride variability in this
subca tegory.
WASTEWATER DISCHARGE RATES
Important production operations that precede and follow reduction
are anode paste preparation and baking, anode cooling, cathode
manufacturing, and degassing and casting of molten aluminum. At
some primary aluminum plants, spent cathodes are reprocessed to
recover cryolite. All of these operations are potential sources
of wastewater and are evaluated to establish effluent limitations
for the primary aluminum subcategory.
Specific wastewater streams associated with the primary aluminum
subcategory are discharges from air pollution emission control
devices for the paste plant, anode bake plant, potline, potroom,
and degassing and those from green anode and briquette contact
cooling, casting contact cooling, cathode reprocessing, and pot
repair-pot soaking. Table X-6 (page 787) lists the production
normalized wastewater discharge rates allocated at BAT for these
wastewater streams. The values represent the best existing
practices of the subcategory, as determined from the analysis of
data collection portfolios and data gathered through comments.
770
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PRIMARY ALUMINUM SUBCATEGORY SECT - X
ANODE AND CATHODE PASTE PLANT WET AIR POLLUTION CONTROL
WASTEWATER
The BAT wastewater discharge rate at proposal for anode paste
plant wet air pollution control was 103.0 1/kkg (24.7
gallons/ton) of paste produced. This rate was allocated for the
users of wet air pollution control devices to control
particulates emanating from the handling of coke and pitch during
anode paste preparation. Of the 29 plants reporting on-site
paste preparation, 22 use dry control devices. Four plants use
water scrubbers, while one does not have any emission control
devices. All of the plants with water scrubbers are once-through
dischargers. The BAT discharge rate at proposal for this stream
was based on 90 percent recycle or reuse of the average water use
of the four plants.
Data submitted through comments and gathered through specific
data requests were used to re-evaluate the proposed anode paste
plant wet air pollution control flow allowance. The same four
plants considered at proposal are used to calculate the
flow allowance at primulgation. The promulgated BAT discharge
rate for this stream is based on 90 percent recycle or reuse of
the average water use of the four plants. Using the data
presented in Table V-l (page 653) the flow allowance is
calculated as 136 1/kkg (33 gal/ton) of paste produced.
The scope of this wastewater stream has also been expanded.
After proposal, it was demonstrated to the Agency that scrubbers
used to control particulate and gaseous emissions from cathode
paste plants are similar to anode paste plant scrubbers. Flow
and production relationships between these operations are
essentially identical.
ANODE BAKE PLANT WET AIR POLLUTION CONTROL WASTEWATER
The BAT wastewater discharge rate at proposal for anode bake
plant wet air pollution control was 49.4 1/kkg (11.9 gallons/ton)
of anode baked. The rate was allocated only for those plants
with wet air pollution control devices. Of the 19 anode baking
operations reported, eight plants were thought to use water for
emission control. The BAT discharge rate used at proposal was
based on 90 percent recycle of the water used at two plants with
the lowest water usage.
After proposal, numerous data were received by the Agency
indicating that baking operations from plant to plant are not
consistent and are fundamentally different. As described in
Section III, three different types of anode bake furnaces are
used: 1) open top ring furnace, 2) closed top ring furnace, and
3) tunnel kiln. Differences in the furnaces create different air
pollution control requirements due to variations in the volumes
of air produced and organic loadings. Production normalized
water discharge, scrubber type, and furnace type are presented in
771
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PRIMARY ALUMINUM SUBCATEGORY SECT - X
Table V-3 (page 656). As shown, water discharge varies
dramatically with furnace type and scrubber type. Therefore,
four different flow allowances are used for this waste stream:
1. Tunnel kilns (1,138 1/kkg, based on 90 percent recycle
at plant 342);
2. Closed top ring furnaces (4,324 1/kkg, based on 90
percent recycle at plant 343);
3. Open top ring furnaces with spray towers only (50 1/kkg,
based on 90 percent recycle at plant 364); and
4. Open top ring furnaces with spray towers and wet
electrostatic precipitators (730 1/kkg, based on actual
discharge at plant 354).
Plant 371 operates a wet ESP and falls between allowances three
and four. The Agency believes allowance number four is more
appropriate for this plant since allowance number three would
require the plant to increase its recycle rate to 99+. Plant 371
currently complies with allowance number four.
ANODE CONTACT COOLING AND BRIQUETTE QUENCHING WATER
The BAT discharge rate at proposal for the anode contact cooling
waste stream was 621 1/kkg (149 gallons/ton) of anode cast. This
was equivalent to 90 percent recycle at the two known discharging
plants (based upon average water use). Four of the thirty-one
primary aluminum facilities were thought to generate this
wastewater stream. Information on water discharged and recycled
was not available for one of the four plants. The two remaining
plants are direct dischargers and do not practice recycle. The
fourth plant reported 100 percent recycle of anode contact
cooling water. Wastewater rates considered at proposal are
presented in Section V of this supplement.
Data and information collected through comments and specific
requests for information have been used to re-evaluate the
proposal anode contact cooling flow allowance. Many commenters
requested the Agency provide a discharge allowance for briquette
quenching since it is a similar operation to anode contact
cooling. In both operations, unbaked anodes and briquettes are
water cooled to facilitate handling. The principal difference
between the two is size. Production normalized water usage rates
for briquette quenching compare favorably with anode contact
cooling, and thus they are included in the flow allowance. Table
V-5 (page 665) presents the production normalized discharge rates
for the 11 plants known to use contact cooling water to cool
anodes or briquettes.
Data presented in Table V-5 indicate plants 345 and 349 use an
inordinately large volume of cooling water when compared to the
other production normalized water usage discharge rates.
Excluding these two plants yields an average water usage of 2,090
1/kkg. The promulgated BAT is based on 90 percent recycle, or
209 1/kkg (50 gal/ton).
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PRIMARY ALUMINUM SUBCATEGORY SECT - X
CATHODE MANUFACTURING
EPA has determined that this operation, for which a discharge
allowance was proposed, does not exist.
At proposal, wastewater from cathode manufacturing was thought to
be the discharge from wet ball milling. The Aluminum Association
has supplied information and data to the Agency indicating this
wastewater source, as described, does not exist. For those
plants listed in the supplemental development document with this
wastewater source, the Aluminum Association has presented the
actual use of water in manufacturing cathode paste:
Plant Water Use
340 Bearing cooling water
346 Bearing cooling water
349 Soaking of potliners
365 Cathode paste plant wet air
pollution control
Thus, only the scrubber liquor at plant 369 and pot repair
wastewater at plant 349 are considered process wastewater.
Correspondence with the corporate office for plant 365 states
that plant 369 also has a scrubbing system for the manufacture of
cathode paste.
At these two plants coal-tar paste is manufactured to seal the
seams of pre-purchased cathodes. During mixing of the paste,
hydrocarbons are emitted and captured with wet scrubbers. This
operation is very similar to anode paste manufacture and its air
pollution control systems. Because the manufacture of cathode
paste is similar to manufacturing anode paste and the water usage
rates are similar, the anode paste plant wet air pollution
control allowance is redefined as anode and cathode paste plant
wet air pollution control.
CATHODE REPROCESSING
The BAT wastewater discharge rate at proposal for cathode
reprocessing was 952 1/kkg (228 gal/ton) of aluminum reduced from
electrolytic reduction. There were five plants in the primary
aluminum subcategory thought to generate wastewater when
reprocessing cathodes. None of these plants reported their
recycle or reuse practices for this waste stream. The BAT
discharge allowance was determined from an average of the five
reported discharge rates. The discharge rates ranged from 169
1/kkg to 1480 i/kkg.
Data gathered through specific data requests after proposal
indicate the flow allowance required for cathode reprocessing
wastewaters was overstated. Plants operating potline wet
773
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PRIMARY ALUMINUM SUBCATEGORY SECT - X
scrubbers and cathode reprocessing commingle the two streams to
recover the fluoride as cryolite. Discharge from cryolite
recovery is then returned to the potline circuit and used as
scrubber liquor. Thus, the bleed from cathode reprocessing is
accomplished with the potline scrubber bleed. There is no
independent discharge from cathode reprocessing, and so the flow
allowance provided is for the potline scrubber bleed. Plants
with cathode reprocessing were included in determining the
potline scrubber flow allowances. A cathode reprocessing flow
allowance is provided in the regulation, but it only applies to
those plants operating dry potline scrubbers (and so not using
cathode reprocessing bleed as makeup for wet scrubber).
The Agency has also changed the production normalizing parameter
for cathode reprocessing from aluminum produced to cryolite
recovered. In this way, a plant may obtain spent potliners from
another facility and still be able to comply with the promulgated
mass limitations.
A flow allowance of 35,028 1/kkg of cryolite recovered is
selected for those plants operating cathode reprocessing and dry
potline scrubbers. This flow allowance is currently demonstrated
at one primary aluminum facility using dry scrubbing. This value
was selected because the other three plants, which reported much
larger discharge rates, reuse the blowdown in the potline
scrubber circuit.
POTLINE WET AIR POLLUTION CONTROL WASTEWATER
The BAT wastewater discharge rate at proposal for the potline air
scrubbing stream was 838 1/kkg (201 gallons/ton) of aluminum
produced from electrolytic reduction. Emissions from potline
reduction operations are controlled by dry or wet processes.
Common dry methods involve sorption of fluorine gases on alumina
followed by fabric filtration for particulate removal. Since
1973, significant progress has been made toward effluent
reduction through the conversion of wet emission control devices
to dry processes. Of the 31 plants surveyed at proposal, there
were still 11 plants using wet processes, including one plant
with no discharge; four plants using a recirculation or recycle
system, with discharges ranging from 592 1/kkg (142 gallons/ton)
to 1,147 1/kkg (277 gallons/ton); and 6 plants with a once-
through system with discharges ranging from 20,210 1/kkg (224
gallons/ton) to 59,200 1/kkg (14,000 gallons/ton). Zero
discharge at one plant was accomplished by complete recycle and
reuse of treated wastewater. The proposed BAT discharge rate for
the potline air scrubbing system was based on the average
discharge rate of the four plants with recycle races ranging from
91 to 99 percent.
After proposing the flow allowance, the Agency examined water
usage as it relates to scrubber type and cell technology. No
obvious trends were apparent, sc the flow allowance was not
adjusted. In addition, no data cr information were received
indicating the production normalized flows used to calculate the
774
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PRIMARY ALUMINUM SUBCATEGORY SECT - X
flow allowance had changed. Therefore, the Agency has
promulgated the flow allowance for potline wet air pollution
control as proposed.
Data and information were received indicating that two plants
have recently installed dry potline scrubbing, leaving nine
plants with wet scrubbers. Of these nine plants, two plants have
not reported sufficient data to determine water usage and recycle
practices. Six plants have recycle rates ranging from 88 to 100
percent, while the last plant does not practice recycle.
POTLINE SO2 WET AIR POLLUTION CONTROL
A flow allowance has been added for scrubbers used to control
sulfur emissions from potlines. Currently there are two plants
operating scrubbers to control SO2 emissions from potlines, which
are preceded by dry fluoride scrubbers using alumina. The
production normalized discharge rates for these two scrubbers are
1,430 1/kkg (343 gal/ton) and 1,250 1/kkg (300 gal/ton) of
aluminum production. Recycle rates are reported as 77 and 75
percent, respectively. The discharge allowance is based on the
average of the two values: 1,340 1/kkg (321 gal/ton).
Sulfur dioxide in these two scrubbers is transferred from the gas
phase to the liquid phase using sodium carbonate as a scrubbing
medium. Requiring 90 percent recycle for these two scrubbers is
not appropriate due to the intricate chemistry involved. Sodium
scrubbers such as these are normally designed to operate at a TDS
level of five percent. By convention, a sodium scrubbing system
is considered to be operating in the concentrated mode when the
TDS concentration in the recirculation stream is about five
percent. The two plants in the primary aluminum subcategory with
sodium scrubbers operate at a TDS concentration of 10 percent.
Increasing the recycle rate at these two plants will necessarily
increase TDS which will affect scrubber performance. At higher
recycle rates, mass transfer capabilities are reduced and
equilibrium within the scrubber liquor may shift, liberating
sulfur dioxide gas.
Makeup water is added to the scrubbing circuit to control the TDS
level. Consequently, blowdown from the circuit results from
excess water in the system.
POTROOM WET AIR POLLUTION CONTROL WASTEWATER
The BAT wastewater discharge rate at proposal for the potroom air
scrubbing stream was 1,305 1/kkg (314 gallons/ton) of aluminum
produced from electrolytic reduction. This rate was allocated
Only for plants using wet air pollution control devices for
potroom emissions. Of the 31 plants surveyed at proposal, eight
practiced potroom emission control either to supplement the
potline gas cleaning system or as the only means of controlling
emissions from the reduction area. All of these plants used some
form of wet scrubbing. Wastewater discharge rates varied
considerably among these plants, ranging from 0 to 227,700 1/kkg
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PRIMARY ALUMINUM SUBCATEGORY SECT - X
(54,600 gal/ton). The dcp data indicated that the presence of
potline scrubbing is not a factor contributing to the large
variations of potroom scrubber water used and discharged. The
proposed BAT discharge rate was based on the average of the
discharge rates of the four plants with recycle systems.
Additional data collected and received after proposing the
potroom scrubber flow allowance have been used to re-evaluate the
allowance. The Agency has learned that plant 349 reported water
usage for experimental foam scrubbers. Water usage of the foam
scrubber and spray towers are not expected to be similar; this is
clearly demonstrated in the reported values.
Updated flow and production data were also received for plants
359 and 360. The new dcp submitted by these two plants indicate
they have installed recycle systems and use horizontal tunnel
roof scrubbers with spray systems. However, plant 360 uses an
inordinately large amount of scrubber liquor when compared to
plant 359 and the other plants. Discharge rates for potroom wet
air pollution control are presented in Table V-12 (page 674). The
promulgated discharge allowance is based on the average discharge
rates at plants 354, 359, 364, and 353 adjusted to 90 percent
recycle. Thus, the flow allowance for potroom wet air pollution
control is 1,660 1/kkg (398 gal/ton) of aluminum reduction
production.
POT REPAIR AND POT SOAKING
A flow allowance for pot repair and pot soaking water was not
provided in the proposed mass limitations because the Agency
believed this stream was site specific. The Agency has given
this stream further attention, however, due to industry
requesting a flow allowance. Data gathered through Section 308
requests found five plants discharging this wastewater. Data
submitted to support the Aluminum Association's report entitled
Aluminum Industry Wastewater Survey indicates a sixth plant
discharges this waste stream. A seventh plant has also been
identified through information supplied in the dcp. The Agency
believes this waste stream is present subcategory-wide because
each plant must repair pots and remove potliners (cathodes). The
complete recycle of this stream was reported by three plants. The
belief that this process can be operated with no discharge has
been confirmed through conversations with industry personnel.
Water is used primarily to soften the liner so that it can be
removed. The Agency is unaware of any water quality restraints
restricting the reuse of this water. Therefore, a zero discharge
allowance is established for this waste stream based on 100
percent reuse.
DEGASSING WET AIR POLLUTION CONTROL
No BAT discharge allowance was provided for degassing scrubber
wastewater in the proposed mass limitation. The Agency believed
many plants had eliminated the need for degassing scrubbers by
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PRIMARY ALUMINUM SUBCATEGORY SECT - X
using alternative fluxing methods. These alternative fluxing
methods reduce chlorine fumes released in the operation and
subsequently eliminate the need to remove fumes from the off-
gases to comply with opacity requirements.
However, it has been demonstrated to the Agency that extensive
retrofits would be required to install alternate in-line fluxing
and filtering. Consequently, the Agency has withdrawn the zero
discharge requirement and provided a discharge allowance based on
the average reported water usage rates. The BAT discharge rate
is 2,609 1/kkg (626 gal/ton) of aluminum refined. Flow reduction
has not been included for this stream due to the nature of the
fume being scrubbed. Essentially, chlorine water will be formed
and recycle methods reducing chlorine concentrations are not
readily available. Aeration could be used to reduce the chlorine
concentration prior to recycle; however, this would only transfer
the point source from one part of the plant to another.
DIRECT CHILL CASTING CONTACT COOLING
Direct chill casting practices and the wastewater discharge from
this operation are similar in the aluminum forming and primary
aluminum reduction plants. The data available do not indicate
any significant difference in the amount of water required for
direct chill casting in a primary aluminum or aluminum forming
plant. For this reason, available wastewater data were
considered together, regardless of the affiliated category, in
establishing BAT effluent limitations.
In all, 27 primary aluminum plants and 61 aluminum forming plants
were considered to have direct chill casting operations at
proposal. Recycle of the contact cooling water is practiced at
30 aluminum forming and 18 primary aluminum plants. Of these, 12
plants indicated that total recycle of this stream made it
possible to avoid any discharge of wastewater; however, the
majority of the plants discharge a bleed stream. The discharge
flow for this operation was based on the average of the best,
which was the average normalized discharge flow of the 29 plants
that practice recycle greater than 90 percent. That flow was
1,999 1/kkg (479 gal/ton) of aluminum product from direct chill
casting.
Evaluation of the flow allowance user at proposal revealed a
mistake in the calculation methodology. A plant practicing only
54 percent recycle was inadvertently included in the
determination of the flow rate. In addition, several primary
aluminum facilities were contacted to clarify dcp responses on
casting methods. Data from the aluminum forming and primary
aluminum facilities were pooled together and those discharging
plants practicing 90 percent recycle or greater (but not 100
percent recycle) were averaged to determine the flow allowance of
1,329 1/kkg (319 gal/ton) of aluminum cast.
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PRIMARY ALUMINUM SUBCATEGORY SECT - X
CONTINUOUS ROD CASTING CONTACT COOLING
The BAT discharge allowance at proposal for continuous rod
casting contact cooling stream was 104 1/kkg (25.0 gal/ton) of
aluminum product from rod casting. This discharge flow was a
reduction of the BPT discharge flow used in aluminum forming
based on primary aluminum and aluminum forming plants using
recycle. Two of the five primary aluminum plants thought to have
continuous rod casting reported recycle, one plant only
periodically discharges the stream, the other plant recycles 99
percent. Also, 17 aluminum forming plants, which recycle a
similar type of cooling stream from direct chill casting,
reported recycle rates of 92 to nearly 100 percent.
No information or data were received by the Agency after proposal
indicating the flow allowance is inappropriate. Therefore, the
continuous rod casting flow allowance is equivalent to that
proposed.
STATIONARY CASTING CONTACT COOLING
In the stationary casting method, molten aluminum is poured into
cast iron molds and generally allowed to air cool. EPA is aware
that spray quenching is used to quickly cool the molten aluminum
once cast into the molds; however, the water is evaporated as it
contacts the molten metal. As such, there is no basis for
providing a pollutant discharge allowance.
SHOT CASTING CONTACT COOLING
Although shot manufacture is not prevalent in the primary
aluminum subcategory, it appears there is one plant manufacturing
shot. The BAT discharge rate for shot casting is based on the
demonstrated water use in the secondary aluminum subcategory. The
shot casting operation in the primary aluminum subcategory is
identical to those in the secondary aluminum subcategory.
Therefore, water use and discharge rates are analogous.
Through specific information requests the Agency has found zero
discharge of shot casting cooling water demonstrated at two
secondary aluminum facilities (of the four reporting this
operation). Both of these plants reported no product quality
constraints due to 100 percent recycle. Based on the
demonstrated zero discharge practices for shot casting the
flow allowance requires zero discharge of process wastewater
pollutants.
REGULATED POLLUTANT PARAMETERS
The Agency placed particular emphasis on the toxic pollutants.
The raw wastewater concentrations from individual operations and
the subcategory as a whole were examined to select certain
pollutants and pollutant parameters for consideration for
limitation. This examination and evaluation, presented in
Section VI, concluded that 23 toxic pollutants are present in
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PRIMARY ALUMINUM SUBCATEGORY SECT - X
primary aluminum wastewaters at concentrations that can be
effectively reduced by identified treatment technologies.
However, the cost associated with analysis for toxic metal
pollutants has prompted EPA to develop an alternative method for
regulating and monitoring toxic pollutant discharges from the
nonferrous metals manufacturing category. Rather than developing
specific effluent mass limitations and standards for each of the
toxic metals found in treatable concentrations in the raw
wastewater from a given subcategory, the Agency is promulgating
effluent mass limitations only for those pollutants generated in
the greatest quantities as shown by the pollutant removal
estimates. The pollutants selected for specific limitation are
listed below:
73. benzo(a)pyrene
114. antimony
121. cyanide
124. nickel
By establishing limitations and standards for certain toxic
pollutants, dischargers will attain the same degree of control
over toxic pollutants as they would have been required to achieve
had all the toxic pollutants been directly limited.
This approach is justified technically since the treatment
performance concentrations used for lime precipitation and
sedimentation technology are based on optimized treatment for
concomitant multiple metals removal. Thus, even though metals
have somewhat different theoretical solubilities, they will be
removed at very nearly the same rate in a lime precipitation and
sedimentation treatment system operated for multiple metals
removal. Filtration as part of the technology basis is likewise
justified because this technology removes metals non-
preferential ly.
The performance values used for toxic organic pollutants were
determined in pilot scale treatability tests performed at a
primary aluminum plant. Data from the study indicate toxic
organic pollutants can be reduced to concentrations equal to or
below the quantification limits for those pollutants. The Agency
has selected benzo(a)pyrene as the only organic for limitation.
Benzo(a)pyrene is the most toxic of the polynuclear aromatic
hydrocarbons selected in Section VI. Each toxic organic
pollutant selected in Section VI was found removable in the pilot
scale treatability study using lime, settle, and filtration
treatment. Therefore, limiting benzo(a)pyrene will effectively
control the other toxic organic pollutants present at treatable
concentrations. Those pollutants effectively controlled by the
limitation of benzo(a)pyrene include:
1. acer.aphthene
39. fluoranthene
55. naphthalene
779
-------
PRIMARY ALUMINUM SUBCATEGORY
SECT - X
72. benzo(a)anthracene
76. chrysene
78. anthracene (a)
79. benzo(ghi)perylene
80. fluorene
81. phenanthrene (a)
82. dibenzo(a,h)anthracene
84. pyrene
(a) — reported together
The discharge allowance for benzo(a)pyrene applies only to those
processes that generate it. For those processes where
benzo(a)pyrene is not present, no discharge allowance has been
provided for benzo(a)pyrene. This means that in calculating
effluent limitations at the end of a combined treatment system,
no allowance for benzo{a)pyrene may be included for these
processes. In addition, monitoring of benzo(a)pyrene from these
processes (at-the-source) will not be required. However,
monitoring could be required at the discretion of the permitting
or control authority. EPA has also amended the specialized
definition in 8421.21 to state that if a permittee chooses to
analyze for benzo(a)pyrene using any EPA - approved analytical
method, any non-detected values will be counted as zeros for the
purpose of determining compliance. This approach is consistent
with the methodology outlined in Section V for developing the
benzo(a)pyrene limitations. The methodology used to develop the
limitations treated the non-detected values from the pilot plant
study as zeros. The detection limit for the approved EPA methods
of GC/MS and gas chromatography are 0.0025 and 0.01 mg/1,
respectively.
The toxic metal pollutants selected for specific limitation in
the primary aluminum subcategory to control the discharges of
toxic metal pollutants are antimony and nickel. Cyanide is also
selected for limitation since the methods used to control
antimony and nickel are not effective in the control of cyanide.
The following toxic pollutants are excluded from limitation on
the basis that they are effectively controlled by the limitations
developed for antimony and nickel:
115. arsenic
116. asbestos
118. cadmium
119. chromium
120. copper
122. lead
125. selenium
128. zinc
EFFLUENT LIMITATIONS
The treatment effectiveness concentrations achievable by
application of the BAT treatment technology are discussed in
Section VII of this supplement. The achievable concentrations
780
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - X
(both one-day maximum and monthly average values) are multiplied
by the BAT normalized discharge flows summarized in Table X-6
(page 787) to calculate the mass of pollutants allowed to be
discharged per mass of product. The results of these
calculations in milligrams of pollutant per kilogram of product
represent the BAT effluent limitations and are presented in Table
X-7 (page 789) for each individual waste stream.
Daily maximum and monthly average treatment effectiveness
concentrations are provided for eleven toxic organic and seven
metallic pollutants that are effectively controlled by the
control of benzo(a)pyrene, antimony and nickel. These values are
displayed in Table VII-1 (page 752) for the convenience of permit
writers. While these pollutants are not specifically limited by
the primary aluminum limitations and standards, permit writers
may elect to include some or all of these pollutants in specific
permits.
781
-------
PRIMARY ALUMINUM SUBCATEGORY SECT
TABLE X-l
CURRENT RECYCLE PRACTICES WITHIN THE
PRIMARY ALUMINUM SUBCATEGORY
No. of Plants
No. of Plants Practicing
With Wastewater Recycle
Anode Paste Plant
4
0
Anode Bake Plant
5
2
Potline
9
6
Pot room
8
6
Degassing
4
0
782
-------
Table X-2
POLLUTANT REMOVAL ESTIMATES FOR PRIMARY ALUMINUM DIRECT DISCHARGERS
TOXIC ORGANICS
-j
oo
u>
TOTAL
nrrirn B
(IT1 ON B
rrniu c
OFnCN C
OPTION E
(FTICN E
R/W W\STC
DlSOWdTD
RfMWFD
Dl90ttM2D
RFMWH)
DLSOKRGH)
RFHWFD
pm.nrrAwr
0
>
G
3
w
5S
G
3
to
G
CO
o
>
t-3
W
Q
O
w
~<
NOTE: U'UON B - Limp Precipitation, SodlnntnMon, (XI SkJranlnR, br-prooess Flow Reduction, nrl Cyanide Precipitation
OPTION C " Opt Inn B, pliw Hjltlnrrfl.i Filtration
nrnoi K ¦ option C, pliw Activated Carbon AHnorptlon
to
M
n
-------
Table X-3
POLLUTANT REMOVAL ESTIMATES FOR PRIMARY ALUMINUM DIRECT DISCHARGERS
INORGANICS - COMBINED METALS DATA BASE (CMDB)
POLLUTANT
—]
00
TOTAL
RAW WASTE
(kg/yr)
OPTION B
DISCHARGED
(kg/yr)
OPTION B
REMOVED
(kg/yr)
OPTION C
DISCHARGED
(kg/yr)
OPTION C
REMOVED
(kg/yr)
Antlraony
11 .202
.0
4,048
.1
7,153
.9
2,718
.0
8.484
.0
Arsenic
1 ,882
.0
1 ,882
.0
0
.0
1 .882
.0
0
.0
Cadmium
388
.8
388
.8
0
.0
283
.4
105
.4
Chromium
1 ,090
.2
485
.8
604
.5
404
.8
685
.4
Copper
2,560
.8
2 .560
.8
0
• 0
2,255
.4
305
.4
Lead
1 .403
.4
694
.0
709
.4
462
.6
940
.8
Nickel
39,481
-8
4,279
.4
35,202
.4
1 ,272
.3
38,209
.6
Selenium
2,331
.4
1,7 34
.9
596
.5
1 ,1 56
.6
1,174
.8
Thai Ilum
419
.1
419
.1
0
.0
419
.1
0
.0
Z Inc
9,208
.3
1 ,908
.4
7,299
.9
1 ,3 30
. 1
7,8 78
.2
TOTAL TOXIC METALS
69.967
.8
18.401
.2
51 .566
.6
12,184
.2
57,783
.6
Cyan Ide
44,5 22
.1
1,215
.8
43.306
• 3
1,215
.8
43,306
.3
TOTAL TOXICS
114.489
.9
31 . 702
.1
82,78/
.9
18,545
.5
95,944
.4
Alumlnum
1 ,616,658
.8
12,953
.9
1 .603,704
.8
8,616
. 7
1.608.042
.1
Fluoride
3,665,283
.7
83.853
.5
3,581 ,430
.2
8 3.85 3
.5
3,581.430
.2
TOTAL NONCONVENT10NALS
5,281 .942
.5
96,807
.4
5,185,135
. 1
92,470
.2
5,189.472
. 3
TSS
20,521,523
.7
69,396
.0
20,452,127
.7
15.035
.8
20,506,487
.9
Oil & Grease
1,071,433
.1
57,830
.0
1 ,013,603
.1
57.830
.0
1,013,603
. 1
TOTAL CONVENT 10NA1.S
21 .592,956
.9
127,226
.0
21 ,465,730
.9
72.865
.8
21.520.091
.1
TOTAL POLLUTANTS
26,989,389
.3
255,735
.5
26, 733,653
.8
183.881
.5
26,805.507
.8
~d
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3
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53
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3
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c
o
>
w
o
o
SO
K
C/)
w
n
n
i
FLOW (l/yr)
5.783,000.000
5.783.000,000
NOTE: TOTAL TOXIC METALS « Antimony f Arsenic + Cadmium + Chromium + Copper + Lead + Nickel + Selenium +
Tha11 Ium + Z 1 nc
TOTAL TOXICS - Cyanide + Total Toxic Metals
TOTAL NONCONVENTIONALS - Aluminum + Fluoride
TOTAL CON VENT ION Al.S = TSS and Oil and Grease
TOTAL POLLUTANTS - Total Toxics + Total NonconventIonaIs + Total Conventlonnls
OPTION B = Lime Precipitation, Sedimentation, Oil Skimming, in-process Flow Reduction, and Cyanide
PrecIpI tat Ion
OPTION C = Option R, plus Multimedia Filtration
-------
Table X-4
POLLUTANT REMOVAL ESTIMATES FOR PRIMARY ALUMINUM DIRECT DISCHARGERS
INORGANICS - ALTERNATE DATA BASE
oo
U1
TOTAL
OPTION B
OPTION B
OPTION C
OPTION <:
RAW WASTE
DISCHARGED
REMOVED
DISCHARGED
REMOVED
POLLUTANT
(kg/y r)
(kR/yr)
(kp,/y r)
(kg/yr)
(kR/yr)
AntImony
97.3
97.3
0.0
97.3
0.0
Arsenic
144.2
74.5
69.7
49.6
94.5
Cadmlum
8.7
8.7
0.0
7.2
1 .5
Chromium
1 .7
1.7
0.0
1 .7
0.0
Copper
1 1 -3
1 1 .3
0.0
1 1 .3
0.0
Lead
46.9
17.5
29.4
11.7
35.2
Nickel
38.2
38.2
0.0
38.2
0.0
Selenium
121 .6
43.8
77.8
29.2
92.4
Thai Hum
67.7
67.7
0.0
49.6
18.1
Z Inc
10.2
10.2
0.0
10.2
0.0
TOTAL TOXIC MF.TAL
547.8
370.9
1 76.9
306.1
241 .7
Cyanide
17,490.0
335.8
17,154.2
160.6
17.329.4
TOTAL TOXICS
18,037.8
706.7
17,331.0
466.7
17,571 .1
F luorIde
72,078.9
30,952.0
41,126.9
30,076.0
42.002.9
TOTAL NONCONVENTIONALS
72,078.9
30.952.0
41.126.9
30,076.0
42.002.9
TSS
112,894.6
11,972.0
100,922.6
2,190.0
110.704.6
Oil h Grease
9,378.9
1.460.0
7,918.9
1 ,460.0
7.918.9
TOTAL CONVENTIONALS
122,273.5
13,432.0
108.841 .5
3.650.0
118.623.5
TOTAL POLI.UTANTS
212,390.2
45,090.7
167.299.4
34,192.7
178.197.5
H
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k;
>
tr1
c:
s
M
55
c:
s
w
c
ro
n
>
M
o
o
»
w
M
n
FLOW (l/yr)
166,000,000
146.000.000
NOTE: TOTAL TOXIC METALS = Antimony + Arsenic + Cadmium + Chromium + Copper + Lead + Nickel + Selenium + Thallium
+¦ Z Inc
TOTAL TOXICS - Total Toxic Metals + Cyanide
TOTAL NONCONVENT10NALS = Fluoride
TOTAL CONVENTiONALS - TSS * Oil & Crease
TOTAL POLLUTANTS - Total Toxics + Total Nonconventlonais + Total Convent lonais
OPTION B = Lime Precipitation. Sedimentation, Oil Sklmmlnp,, In-process Flow Reduction, and Cyanide
Preclpltat Ion
OPTION C » Option, plus Multimedia Filtration
-------
Table X-5
POLLUTANT REMOVAL ESTIMATES FOR PRIMARY ALUMINUM
INORGANICS - TOTAL
oo
POLLUTANT
TOTAL
RAW WASTE
(kR/yr)
OPTION B
discharged
(kK/yr)
OI'TION H
REMOVED
(kg/yr)
OPTION C
DISCHARCEO
(kR/yr)
OPTION C
REMOVED
(kfc/yr)
Ant i inony
A rsenIc
Cadin 1 inn
Chromium
Copper
Lead
Nickel
Selenium
Th a I I 1um
Z I nc
1 1 .799.2
2,026.1
39 7 . 5
1 ,092.0
2.572.1
1 ,4 50.1
39,520.0
2, <153.0
<•86 .8
9,218.6
<^.1^5.^.
1 ,9 56 .4
39/ .5
<•8 7.5
2,572.1
711.5
<•,31 /-6
1 , 7 78 . 7
486 .8
1,918.6
7,153.9
69. 7
0.0
604.5
0.0
738.8
3 5,202./.
674.3
0.0
7.299.9
2.815.3
1.931.6
290.5
406.5
2.266.7
474. 3
1.310.5
1.185.8
468.7
1.340.3
8,484.0
94.5
106.9
685.4
305.4
976.0
38.209.6
1.267.2
18.1
7,8 78.2
TOTAL TOXIC MKTALS
70,515.6
18,772.1
51,743.5
12,490.2
58,025.3
Cyan!de
62,012. 1
1.551.6
60,460.5
I , 3 76.4
60,635.7
TOTAL TOXICS
112,527.7
32 ,<.08.8
100,118.9
19.012.1
113,515.6
A lum I niim
F luor1de
1,616,658.8
3,73 7. 162 .6
12,953.9
114,805.5
1,603,704.8
3,622,557.1
8.616.7
113,929.5
1,608,042.1
3,623.433.1
TOTAL N0NC0NVKNTIONAI.S
5,354,021 .4
1 2 7,759 .4
5,226,261 .9
1 22,546.2
5,231.475.2
TSS
Oil & Crease
20.634,418.3
1,080.812.1
81.368.0
59,2 90.0
20,553.050.3
1 ,021.522.1
17.225.8
59.2 90.0
20,617,192.5
1.021.522.1
TOTAL CONVKNT I ONAI.S
21,715.230./.
1'.0,6 58.0
71.574,572.4
76,515.8
21,638,714.6
TOTAL POLLUTANTS
27.201 .7 79.5
300,826.2
76,900.953.2
218,074.1
76,983.705.3
FLOW (1/yr)
5.929.000,000
5,929,000,000
V
VO
M
3
>
va
K
>
tr1
c
3
M
z
c
3
w
c
w
o
>
m
a
o
va
K
w
in
n
H
i
x
NOTE- TOTAL TOXIC MKTAI.S - Antimony + Arsenic + Cadmium + Chromium I Copper + Lead + Nickel + Selenium *
Th a I II uin » 7. 1 nc
TOTAL TOXICS •' T0t.1l Toxic Metals + Cyanide
TOTAL NONCONVKNTIONALS - AI inn I niim » Fluoride
TOIAI. CONVENT IONAI.S - TSS * Oil and Crease
TOTAL POLLUTANTS = Total Toxics + Total Nonconv ent I una I s + Total Convent, i ona I s
OI'TION B ~ Lime Ptcc I p I I at Ion, Sedimentation, Oil Skimming, I n-process Flow Reduction, and Cyanide
PrpcIp11 a t1 on
OPTION C = Option H, plus Multimedia Filtration
-------
Table X-6
BAT WASTEWATER DISCHARGE RATES FOR THE PRIMARY ALUMINUM SUBCATEGORY
CD
Wastewater Stream
Anode and cathode paste
plant wet air pollution
control
Anode contact cooling and
briquette quenching
Anode bake plant wet air
pollution control
1. Closed top ring
furnace
2. Open top ring furnace
with spray tower only
3. Open top ring furnace
with spray tower and
wet electrostatic
prec ip i tator
4. Tunnel kiln
Cathode reprocessing (when
dry potline scrubbing is
used)
Cathode reprocessing (when
wet potline scrubbing is
used)
BAT Normalized
Discharge Rate
1/kkg gal/ton
Production Normalizing
Parameter
1 36
209
4,324
50
730
1 J 38
35.028
33
50
1 ,037
12
1 75
273
8.400
Paste produced
Anodes and briquettes cast
Anodes baked
Anodes baked
Anodes baked
Anodes baked
Cryolite produced from cathode
reprocess ing
Cryolite produced from cathode
reprocess ing
M
s
>
sa
K
>
G
3
M
25
G
3
(/)
G
CO
n
>
tn
a
o
sa
K
w
w
n
x
-------
Table X-6 (Continued)
BAT WASTEWATER DISCHARGE RATES FOR THE PRIMARY ALUMINUM SUBCATEGORY
oo
oo
Wastewater Stream
Potline wet air pollution
control
Potline SO2 wet air
pollution control
Potroom wet air pollution
control
Pot repair - pot soaking
Degassing wet air pollu-
tion control
BAT Normalized
Discharge Rate
1/kkg gal/ton
838
1 ,341
1 ,660
201
322
398
2,609
626
Production Normalizing
Parameter
Aluminum produced from electro-
lytic reduction
Aluminum produced from
electrolytic reduction
Aluminum produced from electro-
lytic reduction
Aluminum produced from electro-
lytic reduction
Aluminum product from degassing
and fluxing
M
s
>
K
>
C
s
M
25
C
s
in
c
w
o
>
>-3
M
O
O
K
Direct chill casting
coo ling
Continuous rod casting
contact cooling
1 .329
104
319
25.0
Aluminum product from direct
chill casting
Aluminum product from rod
cast ing
in
n
o
>-3
Stationary casting
contact cooling
Aluminum product from station-
ary casting
Shot casting contact
cooling
Aluminum product from station-
ary casting
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - X
TABLE X-7
BAT EFFLUENT LIMITATIONS FOR THE PRIMARY ALUMINUM SUBCATEGORY
Anode and Cathode Paste Plant Wet Air Pollution Control
Maximum for Maximum for
Pollutant or Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of
paste produced
English Units - lbs/million
lbs of paste produced
Acenaphthene
0.005
0.002
Benzo(a)anthracene
0.011
0.005
*Benzo(a)pyrene
0.005
0.002
Benzo(ghi)perylene
0 .005
0.002
Chrysene
0 .011
0.005
Dibenzo(a,h)anthracene
0.005
0.002
Fluoranthene
0 .053
0.025
Pyrene
0.036
0.017
^Aluminum
0.831
0.369
*Ant imony
0.262
0 .117
Arsenic
0.189
0.084
Cadnu urn
0.027
0.011
Chromi urn
0.050
0 .020
Copper
0 .174
0.083
*Fluor ide
8.092
3.590
Lead
0.038
0.018
*Nickel
0.075
0 .050
Selenium
0 .112
0 .050
Zinc
0 .139
0 .057
*Regulated Pollutant
789
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - X
TABLE X-7 (Continued)
BAT EFFLUENT LIMITATIONS FOR THE PRIMARY ALUMINUM SUBCATEGORY
Anode Contact Cooling and Br iquette Quenching
Maximum for Maximum for
Pollutant or Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of
anodes cast
English Units - lbs/million
lbs of anodes cast
Acenaphthene
0.007
0 . 003
Benzo(a)anthracene
0.016
0.007
*Benzo(a)pyrene
0.007
0.003
Benzo(ghi)perylene
0.007
0. 003
Chrysene
0.016
0 . 007
Dibenzo(a,h)anthracene
0.007
0.003
Fluoranthene
0.082
0 . 038
Pyrene
0.056
0 . 026
*Alumi num
1. 277
0 . 566
*Antimony
0.403
0. 180
Arsenic
0. 291
0.130
Cadmium
0.042
0 .017
Chromium
0.077
0 .031
Copper
0 . 268
0. 127
*Fluoride
12.440
5. 518
Lead
0.059
0.027
*Nickel
0.115
0.077
Selenium
0.171
0 . 077
Zinc
0. 213
0 . 088
~Regulated Pollutant
790
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - X
TABLE X-7 (Continued)
BAT EFFLUENT LIMITATIONS FOR THE PRIMARY ALUMINUM SUBCATEGORY
Anode Bake Plant Wet Air Pollution Control (Closed Top
Ring Furnace)
Maximum for Maximum for
Pollutant or Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of anodes baked
English Units - lbs/million lbs of anodes baked
Acenaphthene
0.146
0.067
Benzo(a)anthracene
0.335
0.155
~Benzo(a)pyrene
0.146
0.067
Benzo(ghi)perylene
0.146
0.067
Chrysene
0.335
0.155
Dibenzo(a,h)anthracene
0.146
0.067
Fluoranthene
1.690
0.782
Pyrene
1.151
0.533
~Aluminum
26.420
11.720
~Ant imony
8.345
3.719
Arsenic
6.010
2.681
Cadmium
0.865
0.346
Chromium
1.600
0.349
Copper
5.535
2.638
~Fluoride
257.300
114.200
Lead
1. 211
0.562
~Nickel
2.378
1.600
Selenium
3.546
1.600
Zinc
4.410
1.816
~Regulated Pollutant
791
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - X
TABLE X-7 (Continued)
BAT EFFLUENT LIMITATIONS FOR "THE PRIMARY ALUMINUM SUBCATEGORY
Anode Bake Plant Wet Ai r Pollution Control (Open Top
Ring Furnace With Spray Tower Only)
Maximum for Maximum for
Pollutant or Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg
of anodes baked
English Units - lbs/million
lbs of anodes baked
Acenaphthene
0.002
0.001
Benzo(a)anthracene
0.004
0.002
*Benzo(a)pyrene
0 . 002
0.001
Benzo(ghi)perylene
0 . 002
0.001
Chrysene
0. 004
0.002
Dibenzo(a,h)anthracene
0.002
0.001
Fluoranthene
0 .020
0.009
Pyrene
0.013
0.006
*Aluminum
0.306
0.136
*Ant imony
0 .097
0.043
Arsenic
0 .070
0 .031
Cadmium
0.010
0.004
Chromium
0.019
0.008
Copper
0.064
0.031
*Fluor ide
2 . 975
1.320
Lead
0.014
0.007
*Nickel
0.028
0 .019
Selenium
0 .041
0.019
Zinc
0 .051
0.021
*Regulated Pollutant
792
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - X
TABLE X-7 (Continued)
BAT EFFLUENT LIMITATIONS FOR THE PRIMARY ALUMINUM SUBCATEGORY
Anode Bake Plant Wet Air Pollution Control (Open Top
Ring Furnace With Wet Electrostatic Precipitator and
Spray Tower)
Maximum for Maximum for
Pollutant or Pollutant Property Any One Day Monthly Average
Metric Uni
ts - mg/kg of anodes baked
English Units -
lbs/million lbs of anodes baked
Acenaphthene
0.025
0 .011
Benzo(a)anthracene
0.057
0 .026
*Benzo(a)pyrene
0.025
0 .011
Benzo(ghi)perylene
0.025
0 .011
Chrysene
0.057
0.026
Dibenzo(a,h)anthracene
0 .025
0.011
Fluoranthene
0.285
0.132
Pyrene
0.194
0 . 090
*Alumi num
4.460
1.978
*Ant imony
1.409
0.628
Arsenic
1 . 015
0.453
Cadmium
0.146
0.058
Chromium
0.270
0.110
Copper
0.934
0.445
*Fluor ide
43.440
19.270
Lead
0 . 204
0.095
*Ni ckel
0.402
0.270
Selenium
0.599
0. 270
Zinc
0.745
0.307
*Regulated Pollutant
793
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - X
TABLE X-7 (Continued)
BAT EFFLUENT LIMITATIONS FOR THE PRIMARY ALUMINUM SUBCATEGORY
Anode Bake Plant Wet Air Pollution Control (Tunnel Kiln)
Maximum for Maximum for
Pollutant or Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg
of anodes baked
English Units - lbs/million
lbs of anodes baked
Acenaphthene
0.038
0.018
Benzo(a)anthracene
0.088
0.041
*Benzo(a jpyrene
0.038
0 .018
Benzo(ghi Jperylene
0.038
0.018
Chrysene
0.088
0 .041
Dibenzo(a,h)anthracene
0.038
0 . 018
Fluoranthene
0.445
0 . 206
Pyrene
0. 303
0 .140
*Aluminum
6.953
3 . 084
*Ant imony
2. 196
0 . 979
Arsenic
1.582
0 .706
Cadmium
0. 228
0 . 091
Chromium
0.421
0.171
Copper
1.457
0 . 694
*Fluoride
67 .710
30 .040
Lead
0.319
0 .148
*Nickel
0.626
0 . 421
Selenium
0.933
0 . 421
Z inc
1 .161
0 . 478
*Regulated Pollutant
794
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - X
TABLE X-7 (Continued)
BAT EFFLUENT LIMITATIONS FOR THE PRIMARY ALUMINUM SUBCATEGORY
Cathode Reprocessing (Operated With Dry Pot 1ine Scrubbing
and Not Cominingled With Other
Process or Nonprocess Waters)
Maximum for
Maximum for
Pollutant or Pollutant Property
Any One Day
Monthly Average
Metric Units - mg/kg of
cryolyte recovered
English Units - lbs/million
lbs of cryolite
recovered
Acenaphthene
1.180
0 . 546
Benzo(a)anthracene
2.715
1. 257
*Benzo(a)pyrene
1.181
0 . 547
Benzo(ghi)perylene
1.180
0.546
Chrysene
2.715
1. 257
Dibenzo(a,h)anthracene
1.180
0 . 546
Fluoranthene
13.450
6.235
Pyrene
9.326
4 . 317
~Aluminum
273.200
122.600
~Ant imony
420 . 400
189.200
Arsenic
48.690
21.720
Cadmium
7 . 006
2.802
Chromium
12.960
5.254
Copper
44.840
21. 370
~Cyanide
157.600
70.060
~Fluor ide
29,430.000
3,310.000
Lead
9.808
4 . 554
~Nickel
80.570
35.030
Selenium
28.720
12.960
Z i nc
35 .730
14.710
~Regulated Pollutant
795
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - X
TABLE X-7 (Continued)
BAT EFFLUENT LIMITATIONS FOR THE PRIMARY ALUMINUM SUBCATEGORY
Cathode Reprocessing (Operated With Dry Potline Scrubbing
and Commingled With Other Process or Nonprocess Waters)
Pollutant or Pollutant Property
Maximum for
Any One Day
Maximum for
Monthly Average
Metric Units - mg/kg of cryolite recovered
English Units - lbs/million lbs of cryolite recovered
Acenaphthene
Benzo(a)anthracene
*Benzo(a)pyrene
Benzo(ghi)perylene
Chrysene
Dibenzo(a,h)anthracene
Fluoranthene
Pyrene
~Aluminum
*Ant imony
Arsenic
Cadmium
Chromium
Copper
~Cyanide
~Fluor ide
Lead
~Nickel
Selenium
Zinc
1
2
1
1
2
1
13
9
214
67
48
7
12
44
157
2084
9
19
28
35
. 180
.715
. 181
.180
.715
.180
.690
.326
.000
.610
.690
. 006
. 960
.840
.600
.000
.808
.270
.720
.730
0
1
0
0 .
1,
0,
6,
4,
94,
30,
21.
2,
5,
21,
70.
924,
4 .
12,
12,
14.
546
257
547
546
257
546
339
317
930
120
720
802
254
370
060
800
554
960
960
710
~Regulated Pollutant
796
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - X
TABLE X-7 (Continued)
BAT EFFLUENT LIMITATIONS FOR THE PRIMARY ALUMINUM SUBCATEGORY
Cathode Reprocessing (Operated With Wet Potline Scrubbing)
Maximum for Maximum for
Pollutant or Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg
of cryolite recovered
English Units - lbs/million
lbs of cryolite recovered
Acenaphthene
0.000
0 .000
Benzo(a)anthracene
0 . 000
0.000
*Benzo(a)pyrene
0.000
0.000
Benzo(ghi)perylene
0.000
0.000
Chrysene
0.000
0.000
Dibenzo(a,h)anthracene
0.000
0. 000
Fluoranthene
0.000
0.000
Pyrene
0.000
0.000
*Alumi num
0.000
0.000
*Ant imony
0.000
0.000
Arsenic
0.000
0.000
Cadmium
0.000
0.000
Chromium
0.000
0.000
Copper
0. 000
0.000
*Cyanide
0.000
0.000
* Fluor ide
0.000
0.000
Lead
0.000
0.000
*Nickel
0 . 000
0.000
Selenium
0.000
0.000
Zinc
0 . 000
0.000
~Regulated Pollutant
-
797
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - X
TABLE X-7 (Continued)
BAT EFFLUENT LIMITATIONS FOR THE PRIMARY ALUMINUM SUBCATEGORY
Potline Wet Air Pollution Control (Operated Without Cathode
Reprocess ing)
Maximum for
Maximum for
Pollutant or Pollutant Property
Any
One Day
Monthly Average
Metric Units - mg/kg of aluminum
produced from electrolytic
reduction
English Units - lbs/million lbs
of
aluminum
produced from
electrolytic
reduction
Acenaphthene
0.028
0 .013
Benzo(a)anthracene
0.065
0 .030
*Benzo(a)pyrene
0.028
0 . 013
Benzo(ghi)perylene
0.028
0.013
Chrysene
0.065
0.030
Dibenzo(a,h)anthracene
0.028
0.013
Fluoranthene
0.328
0 .152
Pyrene
0.223
0 . 103
*Aluminum
5.120
2.271
*Ant imony
1.617
0.721
Arsenic
1.165
0.520
Cadmium
0.168
0.067
Chromium
0.310
0. 126
Copper
0.073
0 . 511
*Fluor ide
49.860
22.120
Lead
0 . 235
0.109
*Nickel
0.461
0 . 310
Selenium
0.687
0 . 310
Zinc
0.855
0 . 352
*Regulated Pollutant
798
-------
PRIMARY ALUMINUM SUBCATEGORY
SECT - X
TABLE X-7 (Continued)
BAT EFFLUENT LIMITATIONS FOR THE PRIMARY ALUMINUM SUBCATEGORY
Potline Wet Air Pollution Control (Operated With Cathode
Reprocessing and not Commingled With Other Process or
Nonprocess Waters)
Pollutant or Pollutant Property
Maximum for
Any One Day
Maximum for
Monthly Average
Metric Units - mg/kg of aluminum produced from electrolytic
reduction
English Units - lbs/million lbs of aluminum produced from
electrolytic reduction
Acenaphthene
Benzo(a)anthracene
*Benzo(a)pyrene
Benzo(ghi Jperylene
Chrysene
Dibenzo(a,h)anthracene
Fluoranthene
Pyrene
~Aluminum
~Antimony
Arsenic
Cadmium
Chromium
Copper
*Cyan ide
*Fluor ide
Lead
*Ni ckel
Selenium
Zi nc
0,
0.
0.
0,
0,
0,
0,
0,
5,
10,
1
0
0,
0,
3
703
0.
1
0,
0,
026
065
026
026
065
028
328
223
120
060
165
168
310
073
771
900
235
928
687
855
0 .
0 .
0 ,
0,
0,
0,
0 ,
0,
2,
4,
0,
0,
0,
0,
1.
318,
0,
0 ,
0,
0,
013
030
013
013
030
013
152
103
271
525
520
067
126
511
676
500
109
838
310
352
~Regulated Pollutant
799
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - X
TABLE X-7 (Continued)
BAT EFFLUENT LIMITATIONS FOR THE PRIMARY ALUMINUM SUBCATEGORY
Potline Wet Air Pollution Control (Operated With Cathode
Reprocessing and Commingled With Other Process or Nonprocess
wastewaters)
Maximum for Maximum for
Pollutant or Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum
produced
from electrolytic
reduction
English Units - lbs/million lbs
of aluminum produced from
electrolytic
reduction
Acenaphthene
0.028
0.013
Benzo(a)anthracene
0.065
0.030
*Benzo(a)pyrene
0.028
0.013
Benzo(ghi)perylene
0.028
0.013
Chrysene
0.065
0.030
Dibenzo(a,h)anthracene
0.028
0.013
Fluoranthene
0.328
0 .152
Pyrene
0 . 223
0 .-103
~Aluminum
5.120
2. 271
*Ant imony
1.618
0.721
Arsenic
1.165
0. 520
Cadmium
0.168
0.067
Chromium
0.310
0.126
Copper
0.073
0.511
~Cyanide
3.771
1.676
~Fluoride
49.860
22.130
Lead
0.235
0.109
*Nickel
0 . 461
0.310
Selenium
0.687
0. 310
Zinc
0.855
0 .352
~Regulated Pollutant
800
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - X
TABLE X-7 (Continued)
BAT EFFLUENT LIMITATIONS FOR THE PRIMARY ALUMINUM SUBCATEGORY
Potroom Wet Air Pollution Control
Maximum for Maximum for
Pollutant or Pollutant Property Any One Day Monthly Average
Metric Units - mq/kq of aluminum
produced
from electrolytic
reduct ion
English Units - lbs/million lbs
of aluminum produced from
electrolytic
reduction
Acenaphthene
0.056
0.026
Benzo(a)anthracene
0.129
0.060
*Benzo(a)pyrene
0.056
0.026
Benzo(ghi)perylene
0.056
0.026
Chrysene
0.129
0.060
Dibenzo(a,h)anthracene
0.056
0.026
Fluoranthene
0.649
0 . 300
Pyrene
0.442
0.205
~Aluminum
10.140
4.499
*Ant imony
3 . 204
1.428
Arsenic
2. 307
1.029
Cadmium
0.332
0 .133
Chromium
0.614
0 . 249
Coppe r
2.125
1.013
*Fluor ide
98.770
43.820
Lead
0 . 465
0 . 216
~Nickel
0,913
0.614
Selenium
1. 361
0.614
Zinc
1.693
0.697
~Regulated Pollutant
801
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - X
TABLE X-7 (Continued)
BAT EFFLUENT LIMITATIONS FOR THE PRIMARY ALUMINUM SUBCATEGORY
Potline SO? Emissions Wet Air Pollution Control
Maximum for Maximum for
Pollutant or Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum produced from electrolytic
reduct ion
English Units - lbs/million lbs of aluminum produced from
electrolytic
reduct ion
Acenaphthene
0.045
0.021
Benzo(a)anthracene
0.104
0 .048
*Benzo(a)pyrene
0.045
0 .021
Benzo(ghi)perylene
0.045
0 .021
Chrysene
0.104
0.048
Dibenzo(a,h)anthracene
0.045
0.021
Fluoranthene
0.524
0 . 243
Pyrene
0.357
0.165
~Aluminum
8.194
3.634
*Ant imony
2.588
1.153
Arsenic
1.864
0 .831
Cadmium
0.268
0 .107
Chromium
0.496
0.201
Copper
1.716
0.818
*Fluoride
79 .790
35.400
Lead
0.375
0 .174
*Nickel
0.738
0.496
Selenium
1.100
0 . 496
Zinc
1.368
0 . 563
* Regulated Pollutants
802
-------
PRIMARY ALUMINUM SUBCATEGORY
SECT
TABLE X-7 (Continued)
BAT EFFLUENT LIMITATIONS FOR THE PRIMARY ALUMINUM SUBCATEGORY
Degassing Wet Air Pollution Control
Pollutant or Pollutant Property
Maximum for
Any One Day
Maximum for
Monthly Average
Metric Units - mg/kg of aluminum produced from electrolytic
reduction
English Units - lbs/million lbs of aluminum produced from
electrolytic reduction
Acenaphthene
Benzo(a)anthracene
~Benzo(a)pyrene
Benzoj ghi)perylene
Chrysene
Dibenzo(a,h)anthracene
Fluoranthene
Pyrene
•Aluminum
•Antimony
Arsenic
Cadmium
Chromium
Copper
~Fluoride
Lead
~Nickel
Selenium
Zinc
0.088
0.202
0.088
0.088
0.202
0.088
1.020
0.695
15.940
5,
3
035
627
0.522
0.965
3.340
155.200
0.731
1,
2,
2,
435
139
661
0.041
0.094
0.041
0.041
0.094
0.041
0.472
0.322
070
244
618
0.209
0.391
1.591
68.880
0.339
0.965
0.965
1.096
7,
2,
1,
~Regulated Pollutant
803
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - X
TABLE X-7 (Continued)
BAT EFFLUENT LIMITATIONS FOR THE PRIMARY ALUMINUM SUBCATEGORY
Pot Repair and Pot Soaking
Maximum for Maximum for
Pollutant or Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum produced from electrolytic
reduction
English Units - lbs/million lbs of aluminum produced from
electrolytic
reduction
Acenaphthene
0.000
0.000
Benzo(a)anthracene
0 . 000
0.000
*Benzo(a)pyrene
0 . 000
0.000
Benzo(ghi)perylene
0.000
0 .000
Chrysene
0.000
0 . 000
Dibenzo(a,h)anthracene
0.000
0 . 000
Fluoranthene
0 .000
0.000
Pyrene
0.000
0 . 000
~Aluminum
0 .000
0 . 000
*Antimony
0.000
0 . 000
Arsenic
0 .000
0 . 000
Cadmium
0 . 000
0.000
Chromium
0.000
0.000
Copper
0.000
0 .000
*Fluor ide
0.000
0 .000
Lead
0.000
0.000
~Nickel
0.000
0 . 000
Selenium
0.000
0 .000
Zinc
0.000
0 . 000
~Regulated Pollutant
804
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - X
TABLE X-7 (Continued)
BAT EFFLUENT LIMITATIONS FOR THE PRIMARY ALUMINUM SUBCATEGORY
Pi rect Chill Cast ing Contact Cooling
Maximum for Maximum for
Pollutant or Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum
product from
di rect
chill
casting
English Units - lbs/million lbs
of aluminum
product
from
direct chill
cast ing
Acenaphthene
0.045
0 .021
Benzo(a)anthracene
0.103
0 .048
*Benzo(a)pyrene
0.045
0.021
Benzo(ghi)perylene
0.045
0 .021
Chrysene
0.103
0 .048
Dibenzo(a,h)anthracene
0.045
0 .021
Fluoranthene
0.520
0.240
Phenanthrene
0.045
0.021
Pyrene
0.354
0 .164
~Aluminum
8.120
3.602
*Antimony
2.565
1.143
Arsenic
1 .047
0.824
Cadmium
0 .266
0 .106
Chromium
0 .492
0 .199
Copper
1 .701
0.811
*Fluoride
79.000
35.090
Lead
0.372
0.173
*Nickel
0.731
0 . 492
Selenium
1 . 090
0 . 492
Zinc
1. 356
0. 558
*Regulated Pollutant
805
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - X
TABLE X-7 (Continued)
BAT EFFLUENT LIMITATIONS FOR THE PRIMARY ALUMINUM SUBCATEGORY
Continuous Rod Casting Contact Cooling
Maximum for Maximum for
Pollutant or Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum
product from rod
cast ing
English Units - lbs/million lbs of
aluminum product
from rod
casting
Acenaphthene
0 .004
0 .002
Benzo(a)anthracene
0 . 008
0 .004
*Benzo(a)pyrene
0 .004
0 . 002
Benzo(ghi)perylene
0 . 004
0 .002
Chrysene
0 . 008
0.004
Dibenzo(a,h)anthracene
0.004
0 .002
Fluoranthene
0.041
0 .019
Pyrene
0.028
0 .013
~Aluminum
0.635
0 . 282
*Antimony
0. 201
0.089
Arsenic
0.145
0 . 064
Cadmium
0.021
0 . 008
Chromium
0.038
0 .016
Copper
0.133
0 . 063
*Fluoride
6.188
2.746
Lead
0.029
0 . 014
*Nickel
0.057
0 .038
Selenium
0 . 085
0 .038
Zinc
0. 106
0 .044
~Regulated Pollutant
806
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - X
TABLE X-7 (Continued)
BAT EFFLUENT LIMITATIONS FOR THE PRIMARY ALUMINUM SUBCATEGORY
Stationary Casting or Shot Castinq Contact Cooling
Maximum for Maximum for
Pollutant or Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum product from starionary casting
or shot casting
English Units - lbs/million lbs of aluminum product from
stationary casting or shot casting
Acenaphthene
0.000
0.000
Benzo(a)anthracene
0. 000
0.000
*Benzo(a)pyrene
0.000
0.000
Benzo(ghi)perylene
0.000
0.000
Chrysene
0.000
0 . 000
Dibenzo(a,h)anthracene
0.000
0.000
Fluoranthene
0.000
0.000
Pyrene
0.000
0.000
~Aluminum
0.000
0. 000
~Antimony
0 . 000
0.000
Arsenic
0.000
0. 000
Cadmium
0.000
0.000
Chromium
0.000
0.000
Copper
0.000
0.000
*Fluor ide
0.000
0.000
Lead
0.000
0. 000
*Nickel
0.000
0. 000
Selenium
0.000
0. 000
Z i nc
0.000
0.000
~Regulated Pollutant
807
-------
Pot room Scrubber Liquor
00
O
00
Degassing Scrubber Liquor
Pot line Sf>2 Scrubber Liquor
Cathode Reprocessing Wastewater
Pot line Scrubber Liquor
Anode and Cathode Paste Plant Scrubber Liquor
Anode Bake Pl.int Scrubber Liquor
Chrmlra 1 Add 11 Ion
Anode Contact Coollnp, and Briquette
Quenchinp, Wastewater
Olrecr Chill Canting Contact
Cooling Water
Continuous Rod Casting Contact CoolInK
Water
« Cooling
\ Tower
Recycle .
Oil
SM—lng
Equa 11 -
zatIon
Tank
Removal of
011 and
f.reane
Shot Canting Contact Cooling Water
A —
1 lower #
Complete Krcyclo
Complete K
pot Soaking and Repair Wastewater
ecycle ^
V
Hold lug
Tank
i
Chrmlra1
Proc1 pi tat Ion
ot»
V
Discharge
Setllmeitt at Ion
slmlpr
Sludge Recycle
Sludge Drwator ln<
ittasasAaa
S1 tidge I) ( spona 1
hd
W
M
3
>
W
K
>
tr>
G
3
M
2:
G
3
(/)
G
ffl
n
>
w
CD
o
w
~<
(/)
w
n
i
Stationary Casting Contact Cooling Water
Complete F.vaporat Ion
Figure X-1
BAT TREATMENT SCHEME OPTION A
PRIMARY ALUMINUM SUBCATEGORY
-------
leal Add It I on
Recycle (d)
00
o
vo
Put room Scrubber Liquor
Degassing Scrubber Liquor
fhrml( fl | AHH lllr>n
Cathode Reprocess 1 np. Wastewater (n)
£ ,
CyanIdc
Tree 1p1 tat Ion
T
Potllne Scrubber Liquor (b) 1
_y_
Pot line Scruhber Liquor (c)
Anode and Cathode Paate Plant Scrubber l.lquor
Sed I men-
tat Ion
Vacuum Flit ra-
t Inn and r» I mli'.r
HI«;pti <^«* I
Anode Bake PI ant Scrubber Liquor
Anode Contact Cooling and Briquette Quenching
Wastewater
:'lrcrt Chill Casting Contact Cooling Mater
Continuous Rod Casting Contact Cooling Water
01 I
SkImming
Cool Ing
Tower j
Slot Casting Contact Cooling Water
Recycle*
CooI Inp /
\ Tower J
Remov.il of
011 and
Crease
Complete Recycle
Pot Soaking and Repair Wastewater
Stationary Casting Contact Cooling Water
Sludge Removal
C«>mplerc F.vaporat Ion
Chomlc n1
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(a) Only when dry potllne scrubbing Is present.
(b) Only when cathode reprocessing Is present.
(c) Only when cathode reprocessing Is not present.
(d) When In-process flow reduction Is not practiced,
partial recycle of Anode ami Cathode Paste Srruh-
her. Anode Rake Scrubber, and rot line Scrubber
Wastewater Is required.
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BAT TREATMENT SCHEME OPTION B
PRIMARY ALUMINUM SUBCATEGORY
-------
Backwash
Chemlea 1 A<1<111 Ion
Pot room Scrubber l.luuor ^
Degassing Scruhher l.lquor
Potlltie SO„Scruhher Liquor
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Anode Bake riant Scrubber l.lquor
00" 1
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Wantewat et
Direct ChlU Casting Contact Cooling Water
Continuous Rod Cabling Contact Cooling Water
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V
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(a) Only when dry pot line scrubbing Is present.
(b) Only when cathode reprocessing Is present.
(c) "nly when cathode reprocessing If; not present .
(d^ When In-process flow reduction Is not practiced,
partial recycle of Anode and Cathode I'ar.te Srmb-
her , Anode Hake Scrubber, and Potl1n«» Scrubber
Wastewater I^ required.
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BAT TREATMENT SCHEME OPTION C
PRIMARY ALUMINUM SUBCATEGORY
-------
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BAT TREATMENT SCHEME OPTION E
PRIMARY ALUMINUM SUBCATEGORY
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - XI
SECTION XI
NEW SOURCE PERFORMANCE STANDARDS
The basis for new source performance standards {NSPS) under
Section 306 of the Act is the best available demonstrated
technology (BDT). New plants have the opportunity to design the
best and most efficient production processes and wastewater
treatment technologies, without facing the added costs and
restrictions encountered in retrofitting an existing plant.
Therefore, Congress directed EPA to consider the best
demonstrated process changes, in-plant controls, and end-of-pipe
treatment technologies which reduce pollution to the maximum
extent feasible.
This section describes the control technology for treatment of
wastewater from new sources, and presents mass discharge
limitations of regulated pollutants for NSPS based on the
described control technology.
TECHNICAL APPROACH TO BDT
All of the treatment technology options applicable to a new
source were previously considered for the BAT options. For this
reason, four options were considered for BDT that were identical
to the BAT options discussed in Section X except for Option B.
Option B eliminates three sources of wastewater through the use
of dry air pollution control: anode paste plant wet air
pollution control, anode bake plant wet air pollution control,
and potline wet air pollution control. Degassing wet air
pollution is also eliminated based on alternate in-line fluxing
and filtering methods. For all other waste streams, BDT Option B
is identical to BAT Option B. The treatment technologies used
for the four BDT options are:
OPTION A
o Preliminary treatment with oil skimming (where required)
o Chemical precipitation and sedimentation
OPTION B
o Preliminary treatment with oil skimming (where required)
o Preliminary treatment of cathode reprocessing wastewater
with ferrous sulfate precipitation
o Chemical precipitation and sedimentation
o In-process flow reduction of casting contact cooling
water
o Dry alumina scrubbing of gaseous emissions from anode
paste plants, anode bake plants, potlines, and potrooms
o Alternate in-line fluxing and filtering techniques
813
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - XI
OPTION C
O
O
O
O
O
O
Preliminary treatment with oil skimming (where required)
Preliminary treatment of cathode reprocessing wastewater
with ferrous sulfate precipitation
Chemical precipitation and sedimentation
In-process flow reduction of casting contact cooling
water
Dry alumina scrubbing of gaseous emissions from anode
paste plants, anode bake plants, potlines, and potrooms
Alternate in-line fluxing and filtering techniques
Multimedia filtration
OPTION E
o
o
o
o
o
o
o
Preliminary
Preliminary
with ferrou
Chemical pr
In-process
water
Dry alumina
paste plant
Alternate i
Multimedia
End-of-pipe
treatment with oil skimming (where required)
treatment of cathode reprocessing wastewater
s sulfate precipitation
ecipitation and sedimentation
flow reduction of casting contact cooling
scrubbing of gaseous emissions from anode
s, anode bake plants, potlines, and potrooms
n-line fluxing and filtering techniques
filtration
treatment with activated carbon adsorption
Partial or complete reuse and recycle of wastewater is an
essential part of each option. Reuse and recycle can precede or
follow end-of-pipe treatment. A more detailed discussion of
these treatment options is presented in Section X.
BDT OPTION SELECTION
EPA proposed that the best available demonstrated technology for
the primary aluminum subcategory be based on BAT plus additional
flow reduction. Additional flow reduction was based on the use
of dry air pollution scrubbing on potlines, anode bake plants,
and anode paste plants and elimination of potroom and degassing
scrubber discharges. Potroom scrubbing discharges are eliminated
by design of efficient potline scrubbing (eliminating potroom
scrubbing completely) and the use of center worked prebake cells
and side worked Soderberg cells. Zero discharge of potline
scrubbing is also demonstrated through the reuse of casting
contact cooling water as scrubber liquor makeup. Degassing
scrubbers are eliminated through the use of alternate in-line
fluxing and filtering methods.
These flow reductions are demonstrated at existing plants, but
were not included in BAT because they might involve substantial
retrofit costs at other existing plants. However, new plants can
include these reductions in plant design at no significant
additional cost. Dry scrubbing also prevents the contamination
of scrubbing discharges with toxic organics.
814
-------
PRIMARY ALUMINUM SUBCATEGORY
SECT - XI
Although this technology is demonstrated, information submitted
through comments and gathered by specific data requests indicates
that two possible problems for new sources could be created by
the proposed NSPS, one with respect to continued utilization of
certain cell technologies, the other regarding ability to produce
certain high purity alloys.
Dry potline scrubbing and elimination of potroom scrubbing for
new sources would effectively require center-worked prebake or
horizontal stud Soderberg cell technology. This is because the
other major cell technologies, the side-worked prebake and
vertical Soderberg cell, must use wet scrubbers to control
fluoride emissions due to hooding constraints. EPA's NSPS for
new "green field" primary aluminum sources are based on these
facilities using center-worked prebake and horizontal stud
Soderberg cells, or achieving the effluent limitations that are
associated with the use of dry scrubbing. This is an
environmentally more acceptable process (particularly in terms of
net effluent reductions) because fluoride emissions can be fully
contained without the use of wet scrubbers while capturing and
returning the fluoride to the manufacturing process. See Senate
Committee on Public Works, A Legislative History of the Clean
Water Act, 93d Cong. 1st Sess., Vol. 1 at 172 (new source
performance standards are to reflect "levels of pollution control
which are available through the use of improved production
processes) . "
An issue arises, however, as to whether major expansions of
capacity at existing Soderberg plants are to be classified as new
sources or as major modifications subject to BAT. Dry scrubbing
on vertical Soderberg potline or potroom emissions may not be
feasible, as a practical matter. However, use of horizontal stud
Soderberg technology with dry potline and not potroom scrubbing
is demonstrated. Therefore, construction of new sources or major
expansions do not receive a discharge allowance for potline or
potroom scrubbing.
It appears dry potline scrubbing may result in product quality
constraints due to iron and silicon contamination when recycled
alumina from scrubbers is used as potline feed. Industry
personnel report high purity alloys can be manufactured if only a
small proportion of the plant's capacity is dedicated to the
manufacture of these alloys. Thus, it appears new sources
producing high purity alloys would be at a competitive
disadvantage if they must install dry scrubbing technology
because of a requirement to use more virgin alumina per ton of
product.
The Agency believes this problem to be hypothetical and unlikely
to occur in actuality. Plants with dry scrubbing can avoid
contamination cf these alloys by segregating production of metal
produced from virgin ore from metal produced from alumina
recycled from dry scrubbers. Although this may allow only a
relatively small (10 zo 20) percentage of a plant's production to
be dedicated to certain high purity alloys, EPA is unaware of any
815
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - XI
plant that devotes large percentages of its production capacity
to these specific alloys. Thus, all existing plants that produce
these high purity alloys and have dry scrubbers appear to be
operating without competitive constraint. Therefore, new sources
will not suffer adverse competitive impact as a result of a dry
scrubbing requirement. If a prospective new source is able to
demonstrate that (1) it will dedicate too much capacity to high
purity alloys to utilize all of its recyclable alumina; (2) it is
unable to market its excess recyclable alumina; and (3) the costs
of purchasing excess virgin ore and reprocessing alumina through
the Bayer process are so high as to pose a barrier to entry, the
Agency will entertain rulemaking application to amend NSPS. Since
no demonstration has been made, and the possibility appears very
remote, this proposed NSPS is not altered.
The promulgated NSPS will eliminate discharge of toxic organics
and metals associated with potline and potroom scrubber
discharge, but will not require any significantly different cost
of compliance for new or existing sources. The incompatible
alloys with dry scrubbing are listed below:
1.
1080
6.
5252
2.
1085
7.
5657
3.
1180
8.
7029
4.
1188
9.
A356
5.
2124
10.
A357
Alternate in-line fluxing and filtering is demonstrated
throughout the subcategory. However, industry representatives
claim alternate in-line fluxing and filtering is not capable of
manufacturing all alloys, and therefore, a degassing scrubber
allowance is necessary so that furnace fluxing can be used for
new sources. Each facility known to use alternate in-line
methods was contacted to determine if any of these alloys are
currently manufactured or capable of being manufactured with
alternate in-line fluxing. Table XI-1 (page 818) presents the
results of this survey. As shown in the table, manufacture of
these alloys with alternate in-line fluxing techniques is
possible. Therefore, NSPS is based on alternate in-line fluxing
and filtering, which eliminates the need for wet degassing
scrubbers.
REGULATED POLLUTANT PARAMETERS
The Agency has no reason to believe that the pollutants that will
be found in treatable concentrations in processes within new
sources will be any different than with existing sources.
Accordingly, pollutants and pollutant parameters selected for
limitation under NSPS, in accordance with the rationale of
Sections VI and X, are identical to those selected for BAT. The
conventional pollutant parameters TSS, oil and grease, and pH are
also selected for limitation.
816
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - XI
NEW SOURCE PERFORMANCE STANDARDS
The NSPS discharge flows for anode paste plant, anode bake plant,
potline air scrubbing, and potroom air scrubbing will be zero as
a result of the use of dry air pollution controls. Degassing wet
air pollution control is eliminated through alternate in-line
fluxing and filtering techniques. The remaining stream discharge
flows are the same for all options and are presented in Table XI-
2 (page 819). The mass of pollutant allowed to be discharged per
mass of product is calculated by multiplying the appropriate
effluent concentration (Table VIII-21, Vol-l,page 248) by the
production normalized wastewater discharge flows (1/kkg). New
source performance standards for the primary aluminum subcategory
waste streams are shown in Table XI-3 (page 821).
EPA amended the pH standard for new sources for direct chill
casting contact cooling water to a pH range of 6.0 to 10.0
standard units provided this stream is not commingled with other
process wastewaters. If direct chill casting contact cooling
water is 'commingled with other process waters, it is still
subject to a pH range of 7.0 to 10.0 at all times.
817
-------
Table XI-1
PLANTS CURRENTLY MANUFACTURING OR CAPABLE OF MANUFACTURING
HIGH PURITY ALLOYS USING ALTERNATE IN-LINE FLUXING AND FILTERING
Alloy Type
Plant
Code
5005
5050
5052
5086
5252
5352
5657
7029
7075
4343
350
X
X
X
X
X
X
X
X
353
X
X
X
X
X
X
X
X
X
X
361
X
X
X
X
6101
X
X
X
X
X
X
X
357
X
X
X
X
X
X
X
X
X
X
-------
Table XI-2
NSPS WASTEWATER DISCHARGE RATES FOR THE PRIMARY ALUMINUM SUBCATEGORY
00
Wastewater Stream
Anode paste plant wet air
pollution control
Anode contact cooling and
briquette quenching
Anode bake plant wet air
pollution control
Cathode reprocessing
Potline wet air pollution
control
Potline SO2 wet air
pollution control
Potroom wet air pollution
control
Pot repair - pot soaking
Degassing wet air pollu-
tion control
NSPS Normalized
Discharge Rate
1/kkg gal/ton
0
209
35,028
1 ,341
0
0
50
8.400
322
Production Normalizing
Parameter
Paste produced
Anodes and briquettes cast
Anodes baked
Cryolite produced from cathode
reprocess ing
Aluminum produced from electro-
lytic reduction
Aluminum produced from elec-
trolytic reduction
Aluminum produced from electro-
lytic reduction
Aluminum produced from electro-
lytic reduction
Aluminum product from degassing
and fluxing
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Direct chill casting
coo ling
1 ,329
626
Aluminum product from direct
chill casting
-------
Table XI-2 (Continued)
NSPS WASTEWATER DISCHARGE RATES FOR THE PRIMARY ALUMINUM SUBCATEGORY
oo
K)
o
Wastewater Stream
Continuous rod casting
contact cooling
Stationary and shot
casting contact cooling
NSPS Normalized
Discharge Rate
1/kkg
104
gal/ton
25.0
Production Normalizing
Parameter
Aluminum product from rod
cast ing
Aluminum product from station-
ary casting
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-------
PRIMARY ALUMINUM SUBCATEGORY SECT - XI
TABLE XI-3
NSPS FOR THE PRIMARY ALUMINUM SUBCATEGORY
Anode and Cathode Paste Plant Wet Air Pollution Control
Maximum for Maximum for
Pollutant or Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of
paste produced
English Units - lbs/million
lbs of paste produced
Acenaphthene
0.000
0.000
Benzo(a)anthracene
0.000
0. 000
*Benzo(a)pyrene
0.000
0.000
Benzo(ghi)perylene
0.000
0 . 000
Chrysene
0.000
0 . 000
Dibenzo(a,h)anthracene
0.000
0 .000
Fluoranthene
0. 000
0 . 000
Phenanthrene
0.000
0.000
Pyrene
0 . 000
0.000
*Alumi num
0 . 000
0.000
*Ant imony
0 . 000
0.000
Arsenic
0. 000
0.000
Cadmium
0. 000
0.000
Chromium
0. 000
0.000
Copper
0. 000
0.000
*Fluoride
0 . 000
0.000
Lead
0. 000
0.000
*Nickel
0.000
0.000
Selenium
0.000
0.000
Zinc
0.000
0.000
*Oil & Grease
0.000
0.000
*TSS
0.000
0.000
*pH Within the range of 7.0 to 10.0
at all times
~Regulated Pollutant
821
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - XI
TABLE Xl-3 (Continued)
NSPS FOR THE PRIMARY ALUMINUM SUBCATEGORY
Anode Contact Cooling and Briquette Quenching
Maximum for Maximum for
Pollutant or Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of
anodes cast
English Units - lbs/million
lbs of anodes cast
Acenaphthene
0.007
0 .003
Benzo(a)anthracene
0.016
0 .007
*Benzo(ajpyrene
0.007
0 .003
Benzo(ghi)perylene
0.007
0 .003
Chrysene
0.016
0. 007
Dibenzo(a,h)anthracene
0.007
0 . 003
Fluoranthene
0.082
0 .038
Phenanthrene
0.007
0.003
Pyrene
0.056
0 .026
~Aluminum
1. 277
0 . 566
~Antimony
0.403
0 . 180
Arsenic
0. 291
0.130
Cadmium
0.042
0.017
Chromium
0.077
0.031
Copper
0. 268
0 . 127
*Fluor ide
12.440
5. 518
Lead
0.059
0 . 027
*Nickel
0 .115
0 . 077
Selenium
0.171
0 . 077
Zinc
0 .213
0 . 088
*Oil & Grease
2.090
2. 090
*TSS
3.135
2. 508
*pH Within the range of 7.0 to 10.0
at all times
*Regulated Pollutant
822
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - XI
TABLE Xl-3 (Continued)
NSPS FOR THE PRIMARY ALUMINUM SUBCATEGORY
Anode Bake Plant Wet Air Pollution Control
Maximum for Maximum for
Pollutant or Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg
of anodes baked
English Units - lbs/million
lbs of anodes baked
Acenaphthene
0.000
0.000
Benzo(a)anthracene
0.000
0 . 000
*Benzo(a jpyrene
0.000
0 .000
Benzo(ghi)perylene
0.000
0.000
Chrysene
0.000
0. 000
Dibenzo(a,h)anthracene
0.000
0.000
Fluoranthene
0.000
0.000
Pyrene
0.000
0. 000
~Aluminum
0.000
0. 000
*Ant imony
0.000
0. 000
Arsenic
0.000
0. 000
Cadmium
0.000
0.000
Chromium
0.000
0 . 000
Copper
0.000
0.000
*Fluor ide
0.000
0.000
Lead
0.000
0 . 000
*Nickel
0.000
0.000
Selenium
0.000
0 .000
Zinc
0.000
0 . 000
*Oil & Grease
0.000
0 . 000
*TSS
0.000
0 . 000
*pH Within the range of 7.0 to 10.0
at all times
~Regulated Pollutant
823
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - XI
TABLE Xl-3 (Continued)
NSPS FOR THE PRIMARY ALUMINUM SUBCATEGORY
Cathode Reprocessinq (Operated With Dry Potline
Scrubbing and Not Commingled With Other Process or
Nonprocess Waters)
Maximum for Maximum for
Pollutant or Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg
of cryolite recovered
English Units - lbs/million
lbs of cryolite recovered
Acenaphthene
1.180
0.546
Benzo(a)anthracene
2.715
1.257
~Benzo(a)pyrene
1.180
0. 546
Benzo(ghi)perylene
1.180
0.546
Chrysene
2.715
1 . 257
Dibenzo(a,h)anthracene
1 . 180
0 . 546
Fluoranthene
13.690
6 . 339
Pyrene
9 .326
4 .317
~Aluminum
273.200
122 . 600
~Antimony
420.400
189.200
Arsenic
48.690
21.720
Cadmium
7 .006
2.802
Chromium
12.960
5 .254
Copper
44.840
21. 370
~Cyan ide
157.600
70.060
~Fluor ide
29 ,430.000
3,
310.000
Lead
9.808
4 . 554
~Nickel
80 . 570
35.030
Selenium
28.720
12.960
Zinc
35.730
14.710
~Oil & Grease
350.300
350.300
~tss
2172.000
945.800
~pH Within the range of 7.0 to 10.0
at all times
~Regulated Pollutant
824
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - XI
TABLE Xl-3 (Continued)
NSPS FOR THE PRIMARY ALUMINUM SUBCATEGORY
Cathode Reprocessing (Operated With Dry Potline
Scrubbing and Commingled Wi th Other Process or
Nonprocess Waters)
Maximum for Maximum for
Pollutant or Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of cryolite recovered
English Units - lbs/million lbs of cryolite recovered
Acenaphthene
1.180
0. 546
Benzo (a) an.thracene
2.715
1. 257
*Benzo(a)pyrene
1.181
0 . 547
Benzo(ghi)perylene
1 .180
0. 546
Ch rysene
2.715
1.257
Dibenzo(a,h)anthracene
1.180
0. 546
Fluoranthene
13.690
6. 339
Pyrene
9.326
4.317
*Alumi num
214.000
94.930
*Ant imony
67.600
30.120
Arsenic
48.690
21.720
Cadmium
7.006
2.802
Chromium
12.960
5. 254
Copper
44.840
21.370
~Cyanide
157.600
70.060
~Fluoride
2084 . 000
924.800
Lead
9.808
4.554
~Nickel
19.270
12.960
Selenium
28.720
12.960
Z inc
35.730
14.710
*Oil & Grease
350.300
350.300
*TSS
2172.000
945.800
*pH
Within the range of 7.0
at all times
to 10.0
~Regulated Pollutant
825
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - XI
TABLE Xl-3 (Continued)
NSPS FOR THE PRIMARY ALUMINUM SUBCATEGORY
Potline Wet Ai r Pollut ion Cont rol
Maximum for Maximum for
Pollutant or Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum produced from electrolytic
reduction
English Units - lbs/million lbs of aluminum produced from
electrolytic
reduction
Acenaphthene
0.000
0 . 000
Benzo(a)anthracene
0.000
0 . 000
*Benzo(a)pyrene
0 . 000
0 .000
Benzo(ghi)perylene
0 . 000
0 .000
Chrysene
0 . 000
0 .000
Dibenzo(a,h)anthracene
0.000
0 . 000
Fluoranthene
0.000
0 . 000
Pyrene
0.000
0 .000
*Aluminum
0.000
0 . 000
*Antimony
0.000
0 . 000
Arsenic
0.000
0.000
Cadmium
0.000
0 . 000
Chromium
0.000
0 . 000
Copper
0.000
0.000
*Fluor ide
0.000
0.000
Lead
0 . 000
0.000
*Nickel
0 . 000
0.000
Selenium
0.000
0 .000
Zi nc
0.000
0 .000
*Oil & Grease
0 . 000
0 . 000
*TSS
0 . 000
0 .000
*pH Within the range of 7.0 to 10.0
at all times
^Regulated Pollutant
826
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - XI
TABLE Xl-3 (Continued)
NSPS FOR THE PRIMARY ALUMINUM SUBCATEGORY
Potroom Wet Air Pollution Control
Maximum for Maximum for
Pollutant or Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum produced from electrolytic
reduction
English Units - lbs/million lbs of aluminum produced from
electrolytic reduction
Acenaphthene
0.000
0 . 000
Benzo(a)anthracene
0.000
0 . 000
*Benzo(a)pyrene
0.000
0.000
Benzoj ghi)perylene
0.000
0.000
Chrysene
0.000
0.000
Dibenzo(a,h)anthracene
0 . 000
0.000
Fluoranthene
0 . 000
0.000
Pyrene
0.000
0.000
*Aluminum
0 . 000
0.000
*Ant imony
0 . 000
0.000
Arseni c
0 . 000
0.000
Cadmium
0 . 000
0.000
Chromi um
0 . 000
0.000
Copper
0 . 000
0.000
*Fluor ide
0 .000
0.000
Lead
0.000
0.000
*Nickel
0.000
0.000
Selenium
0.000
0.000
Zinc
0 . 000
0.000
*Oil & Grease
0 .000
0.000
*TSS
0.000
0.000
*pH
Within the range of 7.0 to 10.0
at all times
*Regulated Pollutant
827
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - XI
TABLE Xl-3 (Continued)
NSPS FOR THE PRIMARY ALUMINUM SUBCATEGORY
Potline SO? Emissions Wet Air Pollution Control
Maximum for Maximum for
Pollutant or Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum produced from electrolytic
reduct ion
English Units - lbs/million lbs of aluminum produced from
electrolytic reduction
Acenaphthene 0.045 0.021
Benzo(a)anthracene 0.104 0.048
*Benzo(ajpyrene 0.045 0.021
BenzojghiJperylene ¦ 0.045 0.021
Chrysene 0.104 0.048
Dibenzo(a,h)anthracene 0.045 0.021
Fluoranthene 0.524 0.243
Pyrene 0.357 0.165
*Aluminum 8.194 3.634
~Antimony 2.588 1.153
Arsenic 1.864 0.831
Cadmium 0.258 0.107
Chromium 0.496 0.201
Copper 1.716 0.818
*Fluoride 79.790 35.400
Lead 0.375 0.174
*Nickel 0.738 0.496
Selenium 1.100 0.496
Zinc 1.368 0.563
*Oil & Grease 13.410 13.410
*TSS 20.120 16.090
*pH Within the range of 7.0 to 10.0
at all times
^Regulated Pollutant
828
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - XI
TABLE Xl-3 (Continued)
NSPS FOR THE PRIMARY ALUMINUM SUBCATEGORY
Degassing Wet Air Pollution Control
Maximum for Maximum for
Pollutant or Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum produced from electrolytic
reduction
English Units - lbs/million lbs of aluminum produced from
electrolytic reduction
Acenaphthene
0.000
0.000
Benzo(a)anthracene
0.000
0 . 000
*Benzo(ajpyrene
0.000
0.000
Benzo(ghi)perylene
0.000
0.000
Chrysene
0.000
0.000
Dibenzo(a,h)anthracene
0.000
0.000
Fluoranthene
0.000
0 .000
Pyrene
0.000
0 . 000
~Aluminum
0.000
0 . 000
~Antimony
0.000
0.000
Arsenic
0.000
0.000
Cadmium
0.000
0.000
Chromium
0.000
0 .000
Copper
0.000
0 . 000
~Fluor ide
0. 000
0.000
Lead
0.000
0.000
~Nickel
0.000
0.000
Selenium
0.000
0 . 000
Zinc
0.000
0 . 000
~Oil & Grease
0.000
0 . 000
~TSS
0.000
0.000
~pH
Within the range of 7.0 to 10.0
at all times
~Regulated Pollutant
829
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - XI
TABLE Xl-3 (Continued)
NSPS FOR THE PRIMARY ALUMINUM SUBCATEGORY
Pot Repai r and Pot Soaking
Maximum for Maximum for
Pollutant or Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum produced from electrolytic
refining
English Units - lbs/million lbs of aluminum produced from
electrolytic
reduction
Acenaphthene
0.000
0 . 000
Benzo(a)anthracene
0.000
0.000
*Benzo(a)pyrene
0.000
0.000
Benzo(ghi)perylene
0.000
0.000
Chrysene
0 . 000
0 .000
Dibenzo(a,h)anthracene
0.000
0 . 000
Fluoranthene
0.000
0 .000
Pyrene
0.000
0.000
~Aluminum
0 . 000
0.000
*Ant imony
0.000
0 . 000
Arsenic
0 . 000
0.000
Cadmium
0.000
0 .000
Ch romium
0.000
0.000
Copper
0.000
0.000
*Fluor ide
0.000
0.000
Lead
0 . 000
0.000
*Nickel
0.000
0 . 000
Selenium
0 . 000
0 . 000
Zinc
0.000
0.000
*Oil & Grease
0.000
0.000
*TSS
0.000
0.000
*pH Within the range of 7.0 to 10.0
at all times
~Regulated Pollutant
830
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - XI
TABLE Xl-3 (Continued)
NSPS FOR THE PRIMARY ALUMINUM SUBCATEGORY
Pirect Chill Casting Contact Cooling
Maximum for Maximum for
Pollutant or Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum product from direct chill
casting
English Units - lbs/million lbs of aluminum product from
direct chill casting
Acenaphthene
0.045
0.021
Benzo(a)anthracene
0.103
0.048
*Benzo(a)pyrene
0.045
0.021
Benzo(ghi Jperylene
0.045
0.021
Chrysene
0.103
0.048
Dibenzo(a,h)anthracene
0.045
0.021
Fluoranthene
0.520
0.240
Pyrene
0.354
0.164
*Alumi num
8.120
3.602
*Ant imony
2.565
1 .143
Arsenic
1.847
0.824
Cadmium
0.266
0. 106
Chromium
0.492
0.199
Copper
1.701
0.811
*Fluor ide
79.080
35.090
Lead
0 . 372
0.173
*Nickel
0.731
0.492
Selenium
1. 090
0.492
Zinc
1.356
0.558
*Oil & Grease
13.290
13. 290
*TSS
19.940
15.950
*pH
Within the range of 7.0
at all times
to 10.0
*Regulated Pollutant
831
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - XI
TABLE Xl-3 (Continued)
NSPS FOR THE PRIMARY ALUMINUM SUBCATEGORY
Continuous Rod Casting Contact Cooling
Maximum for Maximum for
Pollutant or Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum product from rod casting
English Units - lbs/million lbs of aluminum product from
rod casting
Acenaphthene
0.004
0 . 002
Benzo(a)anthracene
0.008
0 . 004
*Benzo(a)pyrene
0.004
0 . 002
Benzo(ghi)perylene
0.004
0.002
Chrysene
0.008
0.004
Dibenzo(a,h)anthracene
0.004
0.002
Fluoranthene
0.041
0.019
Pyrene
0 .028
0.013
*Aluminum
0.635
0 . 282
*Antimony
0.201
0.089
Arsenic
0.145
0.064
Cadmium
0. 021
0.008
Chromium
0. 038
0.016
Copper
0.133
0.063
~Fluoride
6.188
2.746
Lead
0.029
0.014
*Nickel
0.057
0.038
Selenium
0.085
0.038
Zinc
0.106
0.044
*Oil & Grease
1.040
1.040
*TSS
1.560
1.248
*pH
Within the range of 7.0 to 10.0
at all times
*Regulated Pollutant
832
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - XI
TABLE Xl-3 (Continued)
NSPS FOR THE PRIMARY ALUMINUM SUBCATEGORY
Stationary Casting or Shot Casti ng Contact Coolinq
Maximum for
Maximum for
Pollutant or Pollutant Property
Any
One Day
Monthly
Average
Metric Units - rag/kg of aluminum
product from
stationary
casting
or shot casti
ng
English Units - lbs/million
lbs
of aluminum product
from
stationary casting
or
shot casting
Acer.aphthene
0.000
0.000
Benzo(a)anthracene
0.000
0.000
* Benzo ( a ) py'rene
0.000
0.000
Benzo(ghi)perylene
0 . 000
0.000
Chrysene
0 . 000
0.000
Dibenzo(a,h)anthracene
0.000
0.000
Fluoranthene
0.000
0.000
Pyrene
0.000
0 . 000
*Aluminurr.
0 .000
0.000
*Antimony
0.000
0.000
Arsenic
0 . 000
0.000
Cadmium
0.000
0 . 000
Chromium
0.000
0.000
Copper
0.000
0.000
*Fluor ide
0.000
0.000
Lead
0.000
0.000
*Nickel
0.000
0.000
Selenium
0.000
0 .000
Zinc
0.000
0.000
*Oil & Grease
0.000
0.000
*TSS
0. 000
0 . 000
*pH Within
the
range of
7.0 to 10.0
at a
11 times
~Regulated Pollutant
033
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - XII
SECTION XII
PRETREATMENT STANDARDS
Section 307(b) of the Act requires EPA to promulgate pretreatment
standards for existing sources (PSES), which must be achieved
within three years of promulgation. PSES are designed to prevent
the discharge of pollutants which pass through, interfere with,
or are otherwise incompatible with the operation of publicly
owned treatment works (POTW). The Clean Water Act of 1977
requires pretreatment for pollutants, such as heavy metals, that
limit POTW sludge management alternatives. Section 307(c) of the
Act requires EPA to promulgate pretreatment standards for new
sources (PSNS) at the same time that it promulgates NSPS. New
indirect discharge facilities, like new direct discharge
facilities, have the opportunity to incorporate the best
available demonstrated technologies, including process changes,
in-plant controls, and end-of-pipe treatment technologies, and to
use plant site selection to ensure adequate treatment system
installation. Pretreatment standards are to be technology-based,
analogous to the best available technology for removal of toxic
pollutants.
This section describes the control and treatment technologies for
pretreatment of process wastewaters from new sources in the
primary aluminum subcategory. Mass discharge limitations of
regulated pollutants are presented based on the described control
technology.
TECHNICAL APPROACH TO PRETREATMENT
Before proposing and promulgating pretreatment standards, the
Agency examines whether the pollutants discharged by the industry
pass through the POTW or interfere with the POTW operation or its
chosen sludge disposal practices. In determining whether
pollutants pass through a well-operated POTW, achieving secondary
treatment, the Agency compares the percentage of a pollutant
removed by POTW with the percentage removed by direct discharger
applying the best available technology economically achievable. A
pollutant is deemed to pass through the POTW when the average
percentage removed nationwide by well-operated POTW, meeting
secondary treatment requirements, is less than the percentage
removed by direct dischargers complying with BAT effluent
limitations guidelines for that pollutant. (See generally, 46 FR
at 9415-16 (January 28, 1981).)
This definition of pass through satisfies two competing
objectives set by Congress: (1) that standards for indirect
dischargers be equivalent to standards for direct dischargers,
while at the same time, (2) that the treatment capability and
performance of the POTW be recognized and taken into account in
835
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - XII
regulating the discharge of pollutants from indirect dischargers.
The Agency compares percentage removal rather than the mass or
concentration of pollutants discharged because the latter would
not take into account the mass of pollutants discharged to the
POTW from non-industrial sources nor the dilution of the
pollutants in the POTW effluent to lower concentrations due to
the addition of large amounts of non-industrial wastewater.
PRETREATMENT STANDARDS FOR EXISTING SOURCES
There are no indirect discharging primary aluminum plants in the
United States. Consequently, the Agency has elected to not
promulgate pretreatment standards for existing sources.
PRETREATMENT STANDARDS FOR NEW SOURCES
Options for pretreatment of wastewaters are based on increasing
the effectiveness of end-of-pipe treatment technologies. All in-
plant changes and applicable end-of-pipe treatment processes have
been discussed previously in Sections X and XI. The options for
PSNS, therefore, are the same as the NSPS options discussed in
Section XI. Although oil and grease is a conventional pollutant
compatible with treatment provided by POTW, oil skimming is
needed for the PSNS treatment technology to ensure proper
removal. Oil and grease interferes with the chemical addition
and mixing required for chemical precipitation treatment
A description of each option is presented in Section X, while a
more detailed discussion, including pollutants controlled by each
treatment process and achievable treatment concentrations is
presented in Section VII of Vol-1.
Treatment technology options for the PSNS are:
OPTION A
o Preliminary treatment with oil skimming (where required)
o Chemical precipitation and sedimentation
OPTION B
o Preliminary treatment with oil skimming (where required)
o Preliminary treatment of cathode reprocessing wastewater
with ferrous sulfate precipitation
o Chemical precipitation and sedimentation
o In-process flow reduction of casting contact cooling
water
o Dry alumina scrubbing of gaseous emissions from anode
paste plants, anode bake plants, potlines, and potrooms
o Alternate in-line fluxing and filtering
836
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - XII
OPTION C
o Preliminary treatment with oil skimming (where required)
o Preliminary treatment of cathode reprocessing wastewater
with ferrous sulfate precipitation
o Chemical precipitation and sedimentation
o In-process flow reduction of casting contact cooling
water
o Dry alumina scrubbing of gaseous emissions from anode
paste plants, anode bake plants, potlines, and potrooms
o Alternate in-line fluxing and filtering
o Multimedia filtration
OPTION E
o Preliminary treatment with oil skimming (where required)
o Preliminary treatment of cathode reprocessing wastewater
with ferrous sulfate precipitation
o Chemical precipitation and sedimentation
o In-process flow reduction of casting contact cooling
water
o Dry alumina scrubbing of gaseous emissions from anode
paste plants, anode bake plants, potlines, and potrooms
o Alternate in-line fluxing and filtering
o Multimedia filtration
o End-of-pipe treatment with activated carbon adsorption
PSNS OPTION SELECTION
The technology basis for promulgated PSNS is identical to NSPS
(Option C). The treatment scheme consists of preliminary
treatment with ferrous sulfate precipitation and oil skimming
(where required), followed by lime precipitation, sedimentation,
in-process flow reduction, dry alumina scrubbing, and filtration.
EPA knows of no demonstrated technology that provides more
efficient pollutant removal than NSPS and BAT technology.
New plants have the opportunity to design and use the best and
most efficient nonferrous metals manufacturing processes and
wastewater treatment technologies without facing the added costs
and restrictions encountered in retrofitting an existing plant.
The additional flow reduction proposed for new sources can be
achieved by the use of dry air pollution scrubbing. The Agency
believes that the installation of dry scrubbing instead of wet
scrubbing in new facilities reduces the cost of end-of-pipe
treatment by reducing the overall volume of wastewater
discharged.
REGULATED POLLUTANT PARAMETERS
Pollutants and pollutant parameters selected for limitation in
accordance with the rationale of Sections VI and X, are identical
to those selected for limitation for BAT with one exception. EPA
is promulgating PSNS for benzo(a)pyrene, cyanide, nickel, and
837
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - XII
fluoride to prevent pass-through. Limitations for antimony have
not been established because it was shown that a well-operated
POTW removes 60 percent and the Agency estimates the model BAT
treatment technology will remove 55 percent. The conventional
pollutants are not limited under PSNS because they are
effectively controlled by POTW. Aluminum is not regulated
because POTW often use it as an aid to enhance settling.
PRETREATMENT STANDARDS
The PSNS discharge flows are identical to the NSPS discharge
flows for all processes. These discharge flows are listed in
Table XII-1 (page 839). The mass of pollutant allowed to be
discharged per mass of product is calculated by multiplying the
achievable treatment concentration (mg/1) (Table VII-21, Vol-1,
page 248) by the normalized wastewater discharge flow (1/kkg).
Pretreatment standards for new sources, as determined from the
above procedure, are shown in Table XII-2 (page 841) for each
waste stream.
Mass-based standards are promulgated for the primary aluminum
subcategory to ensure that the standards are achieved by means of
pollutant removal rather than by dilution. They are particularly
important since the standards are based upon flow reduction;
pollutant limitations associated with flow reduction cannot be
measured by any other way but as a reduction of mass discharged.
838
-------
Table XII - 1
PSNS WASTEWATER DISCHARGE RATES FOR THE PRIMARY ALUMINUM SUBCATEGORY
00
u>
vo
Wastewater Stream
Anode paste plant wet air
poLLution control
Anode contact cooling and
briquette quenching
Anode bake plant wet air
pollution control
Cathode reprocessing
Hotline wet air pollution
control
Potline SO2 wet air
pollution control
Potroom wet air pollution
control
Pot repair - pot soaking
PSNS Normalized
Discharge Rate
1/kkg gal/ton
0
209
35,028
1 ,341
0
50
8,400
322
Production Normalizing
Parameter
Paste produced
Anodes and briquettes cast
Anodes baked
Cryolite produced from cathode
reprocessing
Aluminum produced from electro-
lytic reduction
Aluminum produced from elec-
trolytic reduction
Aluminum produced from electro-
lytic reduction
Aluminum produced from electro-
lytic reduction
M
s
>
>
t-1
c:
s
M
c:
s
uJ
c:
w
o
>
M
o
o
»
UJ
M
o
X
Degassing wet air pollu-
tion control
0
Aluminum product from degassing
and fluxing
Direct chill casting
coo 1ing
1 ,329
626
Aluminum product from direct
chill casting
-------
Table XII-1 (Continued)
PSNS WASTEWATER DISCHARGE RATES FOR THE PRIMARY ALUMINUM SUBCATEGORY
Wastewater Stream
Continuous rod casting
contact cooling
Stationary and shot
casting contact cooling
3
w
C
M
O
O
~<
W
M
O
i
M
M
PSNS Normalized
Discharge Rate Production Normalizing g
I/kkg gal/ton Parameter S
>
104 25.0 Aluminum product from rod »
casting
>
0 0 Aluminum product from station- g
ary casting
3
-------
PRIMARY ALUMINUM SUBCATEGORY
SECT - XII
TABLE XI1-2
PSNS FOR THE PRIMARY ALUMINUM SUBCATEGORY
Anode and Cathode Paste Plant Wet Air Pollution Control
Pollutant or Pollutant Property
Maximum for
Any One Day
Maximum for
Monthly Average
Metric Units - mg/kg of paste produced
English Units - lbs/million lbs of paste produced
Acenaphthene
Benzo(a)anthracene
*Benzo(a)pyrene
Benzo(ghi)perylene
Chrysene
Dibenzo(a,h)anthracene
Fluoranthene
Pyrene
Antimony
Arsenic
Cadmium
Chromium
Copper
*Fluor ide
Lead
~Nickel
Selenium
Zinc
0,
0,
0,
0,
0.
0,
0,
0,
0.
0,
0,
0
0
0
0
0
000
,000
,000
,000
,000
,000
,000
,000
,000
,000
,000
0.000
0.000
,000
,000
,000
,000
,000
0.000
0.000
0.000
0.000
0.000
0.000
000
000
000
000
000
000
000
0.000
0.000
0.000
0.000
0.000
~Regulated Pollutant
841
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - XII
TABLE XI1-2 (Continued)
PSNS FOR THE PRIMARY ALUMINUM SUBCATEGORY
Anode Contact Cooling and Briquette Quenching
Maximum for Maximum for
Pollutant or Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of
anodes cast
English Units - lbs/million
lbs of anodes cast
Acenaphthene
0 . 007
0 . 003
Benzo(a)anthracene
0 . 016
0 . 007
*Benzo(a jpyrene
0.007
0 . 003
Benzo(ghi)perylene
0 . 007
0.003
Chrysene
0 .016
0. 007
Dibenzo(a,h)anthracene
0. 007
0.003
Fluoranthene
0.082
0.038
Pyrene
0. 056
0. 026
Ant imony
0. 403
0. 180
Arsenic
0. 291
0. 130
Cadmium
0. 042
0. 017
Chromium
0.077
0 .031
Copper
0. 268
0 . 127
*Fluoride
12.440
5. 518
Lead
0.059
0 .027
~Nickel
0.115
0.077
Selenium
0.171
0 . 077
Zinc
0. 213
0. 088
~Regulated Pollutant
842
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - XII
TABLE XI1-2 (Continued)
PSNS FOR THE PRIMARY ALUMINUM SUBCATEGORY
Anode Bake Plant Wet Air Pollution Control
Maximum for Maximum for
Pollutant or Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of
anodes baked
English Units - lbs/million.
lbs of anodes baked
Acenaphthene
0.000
0.000
Benzo(a)anthracene
0.000
0. 000
*Benzo(a)pyrene
0.000
0.000
Benzo(ghi)perylene
0.000
0. 000
Chrysene
0.000
0. 000
Dibenzo(a#h)anthracene
0.000
0. 000
Fluoranthene
0.000
0.000
Pyrene
0.000
0.000
Antimony
0 .000
0.000
Arsenic
0.000
0.000
Cadmium
0.000
0 .000
Chromium
0.000
0.000
Copper
0.000
0.000
*Fluor ide
0.000
0.000
Lead
0.000
0.000
*Nickel
0.000
0 .000
Selenium
0.000
0.000
Zinc
0.000
0.000
*Regulated Pollutant
843
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - XII
TABLE XI1-2 (Continued)
PSNS FOR THE PRIMARY ALUMINUM SUBCATEGORY
Cathode Reprocessing (Operated With Dry Potline
Scrubbing and Not Commingled With Other Process or
Nonprocess Waters)
Maximum for Maximum for
Pollutant or Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg
of cryolite recovered
English Units - lbs/million
lbs of cryolite recovered
Acenaphthene
1.180
0.546
Benzo(a)anthracene
2.715
1.257
*Benzo(a)pyrene
1.181
- 0.547
Benzo(ghi)perylene
1.180
0. 546
Chrysene
2.715
1 . 257
Dibenzo(a,h)anthracene
1.180
0 .546
Fluoranthene
13.690
6.339
Pyrene
9.326
4 .317
Ant imony
67.600
30.120
Arsenic
48.690
21 .720
Cadmium
7 .006
2.802
Chromium
12.960
5.254
Copper
44.840
21.370
*Cyanide
157.600
70.060
*Fluoride
2084.000
924.700
Lead
9.808
4.554
*Nickel
19.270
12.960
Selenium
28.720
12.960
Zinc
35.730
14.710
^Regulated Pollutant
844
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - XII
TABLE XII-2 (Continued)
PSNS FOR THE PRIMARY ALUMINUM SUBCATEGORY
Cathode Reprocessing (Operated With Dry Pot 1ine
Scrubbing and Comminqled With Other Process or
Nonprocess
Waters)
Maximum for
Maximum for
Pollutant or Pollutant Property
Any One Day
Monthly Average
Metric Units - mg/kg
of cryolite recovered
English Units - lbs/million
lbs of cryolite
recovered
Acenaphthene
1.180
0.546
Benzo(a)anthracene
2.715
1. 257
*Benzo(a)pyrene
1.181
0.547
Benzo(ghi)perylene
1.180
0.546
Chrysene
2.715
1. 257
Dibenzo(a,h)anthracene
1.180
0. 546
Fluoranthene
13.690
6.339
Pyrene
9.326
4. 317
Ant imony
67.600
30.120
Arsenic
48.690
21.720
Cadmium
7.006
2.802
Chromium
12.960
5.254
Copper
44.840
21.370
*Cyanide
157.600
70.060
*Fluor ide
29,430.000
3,310.000
Lead
9.808
4.554
*Nickel
80.570
35.030
Selenium
28.720
12.960
Zinc
35.730
14.710
*Regulated Pollutant
845
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - XII
Table XI1-2 (Continued)
PSNS FOR THE PRIMARY ALUMINUM SUBCATEGORY
Potline Wet Air Pollution Control
Maximum for Maximum for
Pollutant or Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum produced from electrolytic
reduct ion
English Units - lbs/million lbs of aluminum produced from
electrolytic reduction
Acenaphthene 0.000 0.000
Benzo(a)anthracene 0.000 0.000
*Benzo(a)pyrene 0.000 0.000
Benzo(ghi)perylene 0.000 0.000
Chrysene 0.000 0.000
Dibenzo(afh)anthracene 0.000 0.000
Fluoranthene 0.000 0.000
Pyrene 0.000 0.000
Antimony 0.000 0.000
Arsenic 0.000 0.000
Cadmium 0,000 0.000
Chromium 0.000 0.000
Copper 0.000 0.000
*Fluoride 0.000 0.000
Lead 0.000 0.000
*Nickel 0.000 0.000
Selenium 0.000 0.000
Zinc 0.000 0.000
~Regulated Pollutant
846
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - XII
TABLE XI1-2
PSNS FOR THE PRIMARY
Pot room Wet Ai r
Pollutant or Pollutant Property
(Continued)
ALUMINUM SUBCATEGORY
Pollution Control
Maximum for Maximum for
Any One Day Monthly Average
Metric Units - mg/kg of aluminum produced from electrolytic
reduction
English Units - lbs/million lbs of aluminum produced from
electrolytic reduction
Acenaphthene
0.045
0.021
Benzo(a)anthracene
0.104
0.048
*Benzo(a jpyrene
0.045
0.021
Benzo(ghi)perylene
0.045
0.021
Chrysene
0.104
0.048
Dibenzo(a,h)anthracene
0.045
0.021
Fluoranthene
0.524
0.243
Pyrene
0.357
0.165
Ant imony
2.588
1.153
Arsenic
1.864
0.831
Cadmium
0. 268
0.107
Chromium
0.496
0.201
Copper
1.716
0.818
*Fluoride
79.790
35.400
Lead
0. 375
0.174
*Nickel
0.738
0.496
Selenium
1.100
0.496
Zinc
1.368
0.563
~Regulated Pollutant
847
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - XII
TABLE XII-2 (Continued)
PSNS FOR THE PRIMARY ALUMINUM SUBCATEGORY
Potline SO? Emissions Wet Air Pollution Control
Maximum for Maximum for
Pollutant or Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum produced from electrolytic
reduction
English Units - lbs/million lbs of aluminum produced from
electrolytic reduction
Acenaphthene 0.000 0.000
Benzo(a)anthracene 0.000 0.000
*Benzo(a)pyrene 0.000 0.000
Benzo(ghi)perylene 0.000 0.000
Chrysene 0.000 0.000
Dibenzo(a,h)anthracene 0.000 0.000
Fluoranthene 0.000 0.000
Pyrene 0.000 0.000
Antimony 0.000 0.000
Arsenic 0.000 0.000
Cadmium 0.000 0.000
Chromium 0.000 0.000
Copper 0.000 0.000
~Fluoride 0.000 0.000
Lead 0.000 0.000
*Nickel 0.000 0.000
Selenium 0.000 0.000
Zinc 0.000 0.000
*Regulated Pollutant
848
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - XII
Table XlI-2 (Continued)
PSNS FOR THE PRIMARY ALUMINUM SUBCATEGORY
Degassing Wet Air Pollution Control
Pollutant or Pollutant Property
Maximum for
Any One Day
Maximum for
Monthly Average
Metric Units - mg/kg of aluminum produced from electrolytic
reduction
English Units - lbs/million lbs of aluminum produced from
electrolytic reduction
Acenaphthene
Benzo(a)anthracene
*Benzo(a)pyrene
Benzo(ghi)perylene
Chrysene
Dibenzo(a,h)anthracene
Fluoranthene
Pyrene
Ant imony
Arsenic
Cadmium
Chromium
Copper
*Fluor ide
Lead
*Nickel
Selenium
Zinc
0,
0
0
0,
0 . 000
0 . 000
0. 000
0.000
000
000
000
000
0 . 000
0 .000
0. 000
0 . 000
0.000
0.000
0.000
0 .000
0 . 000
0 . 000
0.000
0.000
0.000
0.000
0.000
0.000
000
000
000
,000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0,
0
0
0,
^Regulated Pollutant
849
-------
•PRIMARY ALUMINUM SUBCATEGORY
SECT -
XII
TABLE XI1-2 (Continued)
PSNS FOR THE PRIMARY ALUMINUM SUBCATEGORY
Pot Repair and Pot Soaking
Maximura for Maximum for
Pollutant or Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum produced from electrolytic
reduction
English Units - lbs/million lbs of aluminum produced from
electrolytic
reduction
Acenaphthene
0.030
0 .000
Benzo(a)anthracene
0.000
0 .000
*Benzo(a)pyrene
0.0'DO
0 .000
Benzo(ghi)perylene
0. 0©D
0.000
Chrysene
0.090
0.000
Dibenzo(a,h)anthracene
0.000
0 .000
Fluoranthene
0.900
0 .000
Pyrene
0.000
0 .000
Ant imony
0 .£>©0
0.000
Arsenic
0 . QD0
0 .000
Cadmium
0.00(Q
0 . 000
Chromium
o.ooo
0 .000
Copper
0 .000
0 .000
*Fluor ide
0. 000
0 .000
Lead
0 .000
0 .000
*Nickel
0 .000
0 .000
Selenium
0 . O-D O
0 .000
Zinc
0.000
0 .000
*Regulated Pollutant
8 5 0
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - XII
TABLE XII-2 (Continued)
PSNS FOR THE PRIMARY ALUMINUM SUBCATEGORY
Pi rect Chi 11 Casting Contact Cooling
Pollutant or Pollutant Property
Maximum for
Any One Day
Maximum for
Monthly Average
Metric Units - mg/kg of aluminum product from direct chill
casting
English Units - lbs/million lbs of aluminum product from
direct chill casting
Acenaphthene
0.045
Benzo(a)anthracene
0.103
*Benzo(a)pyrene
0.045
Benzo(ghi)perylene
0.045
Chrysene
0.103
Dibenzo(a,h)anthracene
0.045
Fiuoranthene
0. 520
Pyrene
0. 354
Ant imony
2. 565
Arsenic
1.847
Cadmium
0. 266
Chromium
0.492
Copper
1.701
*Fluor ide
79.080
Lead
0.372
*Nickel
0.731
Selenium
1.090
Zinc
1. 356
*Regulated Pollutant
0.021
0.048
0.021
021
048
021
240
0.164
1.143
824
106
199
0,
0
0
0.811
35.090
0. 173
0.492
0.492
0. 558
851
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - XII
Table Xll-2 (Continued)
PSNS FOR THE PRIMARY ALUMINUM SUBCATEGORY
Continuous Rod Castinq Contact Cooling
Maximum for Maximum for
Pollutant or Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg
of aluminum
product from
i rod casting
English Units - lbs/million lbs
of aluminum
product from
rod casting
Acenaphthene
0.004
0.002
Benzol a)anthracene
0.008
0.004
ABenzo(a)pyrene
0.004
0 .002
Benzo(ghi)perylene
0.004
0.002
Chrysene
0.008
0.004
Dibenzo(a,h)anthracene
0.004
0.002
Fluoranthene
0.041
0.019
Pyrene
0.028
0.013
Antimony
0.201
0.089
Arsenic
0 .145
0.064
Cadmium
0.021
0.008
Chromium
0.038
0.016
Copper
0.133
0.063
~Fluoride
6.188
2.746
Lead
0.029
0.014
~Nickel
0.057
0.038
Selenium
0.085
0.038
Zinc
0.106
0.044
~Regulated Pollutant
852
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - XII
TABLE XII-2 (Continued)
PSNS FOR THE PRIMARY ALUMINUM SUBCATEGORY
Stationary Casting or Shot Casting Contact Cooling
Maximum for Maximum for
Pollutant or Pollutant Property Any One Day Monthly Average
Metric Units - mg/kkg of aluminum product from stationary casting
or shot casting
English Units - lbs/billion lbs of aluminum product from
stationary casting or shot casting
Acenaphthene
0.000
0.000
Benzo(a)anthracene
0.000
0.000
*Benzo ( a ) pyirene
0 .000
0.000
Benzo(ghi)perylene
0.000
0 .000
Chrysene
0.000
0 .000
Dibenzo(a,h)anthracene
0 . 000
0.000
Fluoranthene
0 .000
0.000
Pyrene
0 .000
0 .000
Ant imony
0.000
0 .000
Arsenic
0 .000
0 . 000
Cadmium
0.000
0.000
Chromium
0.000
0 .000
Copper
0.000
0.000
*Fluor ide
0.000
0.000
Lead
0 .000
0.000
*Nickel
0.000
0.000
Selenium
0.000
0.000
Zinc
0.000
0.000
~Regulated Pollutant
853
-------
PRIMARY ALUMINUM SUBCATEGORY SECT - XIII
SECTION XIII
BEST CONVENTIONAL POLLUTANT CONTROL TECHNOLOGY
EPA is not promulgating best conventional pollutant control
technology (BCT) for the primary aluminum subcategory at this
time.
855
-------
NONFERROUS METALS MANUFACTURING POINT SOURCE CATEGORY
DEVELOPMENT DOCUMENT SUPPLEMENT
for the
Secondary Aluminum Smelting Subcategory
William K. Reilly
Administrator
Rebecca Hanmer
Acting Assistant Administrator for Water
Martha Prothro, Director
Office of Water Regulations and Standards
,
-------
SECONDARY ALUMINUM SUBCATEGORY
TABLE OF CONTENTS
Section Page
I SUMMARY AND CONCLUSIONS 067
II RECOMMENDATIONS 871
III INDUSTRY PROFILE 889
Description of Secondary Aluminum Production 889
Raw Materials 889
Preliminary Treatment 889
Smelting and Refining 891
Process Wastewater Sources 893
Other Wastewater Sources 894
Age, Production and Process Profile 894
IV SUBCATEGORY AT ION 901
Factors Considered in Subdividing the Secondary 901
Aluminum Subcategory 901
Other Factors 903
Production Normalizing Parameters 903
V WATER USE AND WASTEWATER CHARACTERISTICS 905
Wastewater Sources, Discharge Rates and 906
Characteristics
Scrap Drying Wet Air Pollution Control 909
Scrap Screening and Milling 909
Dross Washing 909
Demagging Wet Air Pollution Control 909
Delacquering Wet Air Pollution Control 910
Ingot Conveyer Casting 910
Direct Chill Casting Contact Cooling Water 910
Shot Casting Contact Cooling Water 911
Stationary Casting Cooling 911
VI SELECTION OF POLLUTANTS 94 3
Conventional and Nonconventional Pollutant 944
Parameters
Conventional and Nonconventional Pollutant 944
Parameters Selected
Toxic Pollutants 945
Toxic Pollutants Never Detected 945
Toxic Pollutants Never Found Above Their 945
Analytical Quantification Limit
861
-------
SECONDARY ALUMINUM SUBCATEGORY
TABLE OF CONTENTS
Section Page
VI Toxic Pollutants Present Below Concentrations 946
Achievable by Treatment
Toxic Pollutants Detected in a Small Number 946
of Sources
Toxic Pollutants Selected for Consideration for 951
Establishing Limitations
VII CONTROL AND TREATMENT TECHNOLOGIES 9 59
Technical Basis of Existing Regulations 959
Scrap Drying Wet Air Pollution Control 960
Scrap Screening and Milling Wastewater 960
Dross Washing Wastewater 960
Demagging Wet Air Pollution Control 960
Delacquering Wet Air Pollution Control 961
Ingot Conveyer Casting Contact Cooling 961
Shot Casting Contact Cooling 962
Control and Treatment Options Considered 962
Option A 962
Option C 962
Control and Treatment Options Rejected 963
VIII COSTS, ENERGY AND NONWATER QUALITY ASPECTS 965
Treatment Options Considered 965
Option A 965
Option C 965
Cost Methodology 966
Nonwater Quality Aspects 967
Energy Requirements 967
Solid Waste 967
Air Pollution 968
IX BEST PRACTICABLE CONTROL TECHNOLOGY CURRENTLY 973
AVAILABLE
X BEST AVAILABLE TECHNOLOGY ECONOMICALLY ACHIEVABLE 975
Technical Approach to BAT 976
Option A 977
Recycle of Casting Contact Cooling Water 977
Recycle of Water Used in Wet Air Pollution Control 977
Option C 978
862
-------
SECONDARY ALUMINUM SUBCATEGORY
TABLE OF CONTENTS
Section Page
X Industry Cost and Pollutant Removal Estimates 978
Pollutant Removal Estimates 978
Compliance Costs 979
BAT Option Selection 979
Wastewater Discharge Rates 981
Scrap Drying Wet Air Pollution Control Wastewater 981
Scrap Screening and Milling 981
Dross Washing Wastewater 981
Demagging Wet Air Pollution Control 982
Delacquering Wet Air Pollution Control 983
Direct Chill Casting Contact Cooling Water 983
ingot Conveyer Casting Contact Cooling Water 984
Stationary Casting Contact Cooling Water 984
Shot Casting Contact Cooling Water 985
Regulat.ed Pollutant Parameters 985
Effluent Limitations 986
XI New Source Performance Standards 997
Introduction 997
Technical Approach to BDT 998
BDT Option Selection 998
Regulated Pollutant Parameters 998
New Source Performance Standards 999
XII PRETREATMENT STANDARDS 1007
Technical Approach to Pretreatment 1007
Pretreatment Standards for Existing and New Sources 1008
Option A 1008
Option C 1008
Industry Cost and Pollutant Removal Estimates 1009
PSES and PSNS Option Selection 1009
Regulated Pollutant Parameters 1009
Pretreatment Standards 1010
XIII BEST CONVENTIONAL POLLUTANT CONTROL TECHNOLOGY 1025
863
-------
SECONDARY ALUMINUM SUBCATEGORY
LIST OF TABLES
Table Title Page
III-l Initial Operating Year Summary of Plants in 895
the Secondary Aluminum Subcategory by
Discharge Type
III-2 Production Ranges for Smelters and Refiners 896
of the Secondary Aluminum Subcategory
III-3 Summary of Subcategory Processes and 897
Associated Waste Streams
V—1 Water Use and Discharge Rates for Scrap Drying 912
Wet Air Pollution Control
V-2 Water Use and Discharge Rates for Scrap 913
Screening and Milling
V-3 Water Use and Discharge Rates for Dross Washing 914
V-4 Secondary Aluminum Sampling Data - Dross 915
Washing Raw Wastewater
V-5 Water Use and Discharge Rates for 918
Demagging Wet Air Pollution Control
V-6 Secondary Aluminum Sampling Data - Demagging 919
Scrubber Liquor Raw Wastewater
V-7 Water Use and Discharge Rates for 923
Delacquering Wet Air Pollution Control
V-8 Water Use and Discharge Rates for 924
Ingot Conveyer Casting
V-9 Water Use and Discharge Rates for 925
Shot Casting
V-10 Secondary Aluminum Sampling Data - Ingot 926
Conveyer Casting Contact Cooling Water,
Raw Wastewater
V-ll Secondary Aluminum Sampling Data - Demagging 927
Wet Air Pollution Control and Casting Contact
Cooling Combined Raw Wastewater
V-12 Secondary Aluminum Sampling Data - Treatment 929
Plant Samples, Plant A
V-13 Secondary Aluminum Sampling Data - Treatment 931
Plant Samples, Plant B
864
-------
de
4
5
1
2
I-
I-
1
2
-1
-2
-3
-4
-5
SECONDARY ALUMINUM SUBCATEGORY
LIST OF TABLES
Title Page
Secondary Aluminum Sampling Data - Treatment 933
Plant Samples, Plant D
Secondary Aluminum Sampling Data - Treatment 936
Plant Samples, Plant E
Frequency of Occurrence of Toxic Pollutants 953
Secondary Aluminum Raw Wastewater
Toxic Pollutants Never Detected 957
Cost of Compliance for the Secondary 970
Aluminum Subcategory Direct Dischargers
Cost of Compliance for the Secondary 971
Aluminum Subcategory Indirect Dischargers
Current Recycle Practices Within the Secondary 987
Aluminum Subcategory
Pollutant Removal Estimates for Secondary 988
Aluminum Direct Dischargers
Raw Wastewater Discharge Rates for the 989
Secondary Aluminum Subcategory
BAT Effluent Limitations for the Secondary 990
Aluminum Subcategory
NSPS Wastewater Discharge Rates for the 1000
Secondary Aluminum Subcategory
NSPS for the Secondary Aluminum Subcategory 1001
Pollutant Removal Estimates for the Secondary 1011
Aluminum Indirect Dischargers
PSES Wastewater Discharge Rates for the 1012
Secondary Aluminum Subcategory
PSNS Wastewater Discharge Rates for the 1014
Secondary Aluminum Subcategory
PSES for the Secondary Aluminum Subcategory 1016
PSNS for the Secondary Aluminum Subcategory 1020
865
-------
SECONDARY ALUMINUM SUBCATEGORY
LIST OF FIGURES
Table Title Page
III-l Secondary Aluminum Smelting Process 898
III-2 Geographic Locations of Secondary Aluminum 899
Plants
V-l Sampling Sites at Secondary Aluminum Plant A 938
V-2 Sampling Sites at Secondary Aluminum Plant B 939
V-3 Sampling Sites at Secondary Aluminum Plant C 940
V-4 Sampling Sites at Secondary Aluminum Plant D 941
V-5 Sampling Sites at Secondary Aluminum Plant E 942
X-l BAT Treatment Scheme Option A, Secondary 995
Aluminum Subcategory
X-2 BAT Treatment Scheme Option C, Secondary 996
Aluminum Subcategory
866
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - I
SECTION I
SUMMARY AND CONCLUSIONS
On April 8, 1974, EPA promulgated technology-based effluent
limitations guidelines and standards for the secondary aluminum
smelting subcategory of the nonferrous metals manufacturing point
source category. These included BPT, and BAT, effluent
limitations and NSPS and PSNS (standards). The purpose of these
effluent limitations and standards was to limit the quantities of
total suspended solids, chemical oxygen demand, fluoride,
ammonia, aluminum, and copper, and the range of pH discharged in
secondary aluminum smelting wastewaters. On December 15, 1976,
EPA promulgated technology-based pretreatment standards for
existing sources (PSES) in the secondary aluminum subcategory.
The purpose of these standards was to limit the quantities of
ammonia, oil and grease, and the range of pH introduced into
publicly owned treatment works in secondary aluminum smelting
wastewater discharges.
Under the settlement agreements, EPA was required to develop BAT
limitations and pretreatment and new source performance standards
for pollutants discharged from twenty one specific industrial
point source categories, including secondary aluminum smelting
taking into account a specific list of 65 pollutants and classes
of pollutants. The list of 65 classes was subsequently clarified
by expanding to a list of 129 specific toxic pollutants. Congress
amended the Clean Water Act in 1977 to encompass most provisions
of the settlement agreements, including the list of 65 classes of
pollutants. As a result of the settlement agreements and the
Clean Water Act Amendments, EPA undertook an extensive program to
develop technology-based BAT limitations and pretreatment and new
source standards for the toxic and other pollutants in the twenty
one categories.
EPA promulgated modifications to BAT, NSPS, PSES and PSNS for the
secondary aluminum subcategory pursuant to the provisions of the
Settlement Agreement and Sections 301, 304, 306, and 307 of the
Clean Water Act and as amended. Consideration must be given to
incorporation of limits on priority pollutant levels in
discharges in these modified standards. This supplement provides
a compilation and analysis-of the background material used to
develop these effluent limitations and standards.
After promulgation of amendments substantially revising BAT, NSPS
and pretreatment for this subcategory, the Aluminum Association,
Kaiser Aluminum and Chemical Core., Reynolds Metals Company, The
Aluminum Recycling Association, and others filed petitions for
review of the amended regulation.
In November, 1985 the aluminum parties entered into two
settlement agreements which resolved issues raised by petitioners
related to the primary and secondary aluminum subcategories. In
867
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - I
accordance with the settlement agreements, EPA published a notice
of proposed rulemaking on May 20, 1986 and solicited comments.
EPA promulgated final amendments for the Secondary Aluminum
Smelting Subcategory on July 7, 1987 (52 FR 25552). The flow
basis for two building blocks, ingot conveyer casting and
demagging wet air pollution control, were revised based on a
re-evaluation of data available in the administrative record of
this rulemaking
The secondary aluminum subcategory is comprised of 47 plants. Of
the 47 plants, 10 discharge directly to waters of the U.S.
(rivers, lakes, or streams); 14 discharge to publicly owned
treatment works (POTW); and 23 achieve zero discharge of process
wastewater.
EPA first studied the secondary aluminum subcategory to determine
whether differences in raw materials, final products,
manufacturing processes, equipment, age and size of plants, water
usage, required the development of separate effluent limitations
and standards for different segments of the subcategory. This
involved a detailed analysis of wastewater discharge and treated
effluent characteristics, including (1) the sources and volume of
water used, the processes used, and the sources of pollutants and
wastewaters in the plant; and (2) the constituents of
wastewaters, including toxic pollutants.
EPA also identified several distinct control and treatment
technologies (both in-plant and end-of-pipe) applicable to the
secondary aluminum subcategory. The Agency analyzed both
historical and newly generated data on the performance of these
technologies, including their nonwater quality environmental
impacts (air quality impacts and solid waste generation) and
energy requirements. EPA also studied various flow reduction
techniques reported in the data collection portfolios (dcp) and
plant visits.
Engineering costs were prepared for each of the control and
treatment options considered for the subcategory. These costs
were then used by the Agency to estimate the impact of
implementing the various options on the subcategory. For each
control and treatment option that the Agency found to be most
effective and technically feasible in controlling the discharge
of pollutants, the number of potential closures, number of
employees affected, and impact on price were estimated. These
results are reported in a separate document entitled Economic
Impact Analysis of Effluent Limitations and Standards for the
Nonferrous Smelting and Refining Industry (EPA number).
Based on consideration of the above factors, EPA identified
various control and treatment technologies which formed the basis
for BPT and selected control and treatment appropriate for each
set of limitations and standards. The mass based, production
related limitations and standards for BPT, BAT, NSPS, PSES and
PSNS are presented in Section II.
868
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - I
For BAT, the Agency has built upon the BPT basis of lime
precipitation and sedimentation by adding in-process control
technologies, preliminary treatment of ammonia by steam
stripping, preliminary treatment of phenolics by activated carbon
adsorption, and multimedia filtration. In-process control
technologies include recycle or reuse of process water from wet
air pollution control and metal contact cooling. Filtration is
added as an effluent polishing step to further reduce metals and
suspended solids concentrations. To meet the BAT effluent
limitations based on this technology, the secondary aluminum
subcategory is estimated to incur a capital cost of $1.1 million
(1982 dollars) and an annual cost of $0.64 million (1902
dollars).
The best demonstrated technology (BDT), which is the technical
basis of NSPS, is equivalent to BAT with the addition of dry
milling to eliminate the discharge from dross washing. In
establishing BDT, EPA recognizes that new plants have the
opportunity to implement the best and most efficient
manufacturing processes and treatment technology. Treatment of
toxic metals is based upon lime precipitation, sedimentation, and
filtration. Oil skimming for the control of oil and grease and
preliminary treatment of phenolics by activated carbon adsorption
are also included.
Pretreatment star.dards for existing sources are based on the same
technology as BAT. The technology basis is in-process flow
reduction, ammonia steam stripping preliminary treatment,
activated carbon adsorption preliminary treatment, lime
precipitation, sedimentation, and multimedia filtration. To meet
PSES, the secondary aluminum subcategory is estimated to incur a
capital cost of $2.3 million (1982 dollars) and an annual cost of
$1.4 million (1982 dollars).
For pretreatment standards for new sources, the technology basis
of in-process flow reduction, preliminary treatment, and end-of-
pipe technology is equivalent to NSPS. As such, PSNS are
identical to NSPS for all waste streams.
869
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - II
SECTION II
RECOMMENDATIONS
This section contains a summary of the effluent limitations and
standards which apply to the secondary aluminum subcategory
taking into account the promulgated amendments of March 8, 1984
and July 7, 1987.
1. EPA has divided the secondary aluminum subcategory into
nine subdivisions or building blocks for the purpose of effluent
limitations and standards. These building blocks are:
(a) Scrap drying wet air pollution control,
(b) Scrap screening and milling,
(c) Dross washing,
(d) Demagging wet air pollution control,
(e) Delacquering wet air pollution control,
(f) Direct chill casting contact cooling,
(g) Stationary casting contact cooling,
(h) Ingot conveyer casting contact cooling, and (i)
Shot casting contact cooling.
2. EPA promulgated BPT effluent limitations for the secondary
aluminum subcategory on April 8, 1974, as Subpart C of 40
CFR Part 421. EPA has not promulgated any modifications
to BPT effluent limitations. The BPT effluent
limitations apply to discharges resulting from magnesium
removal processes (demagging using either chlorine or
aluminum fluoride) and wet residue processes. BPT was
promulgated based on the performance achievable by the
application of chemical precipitation and sedimentation
(lime and settle) technology. The following BPT effluent
limitations were promulgated for existing sources:
(a) The following limitations establish the quantity or
quality of pollutants or pollutant properties, which
may be discharged by a point source subject to the
provisions of this subpart and which uses water for
metal cooling, after application of the best
practicable control technology currently available:
There shall be no discharge of process wastewater
pollutants to navigable waters.
(b) The following limitations establish the quantity or
quality of pollutants or pollutant properties which may
be discharged by a point source subject to the
provisions of this subpart and which uses aluminum
fluoride in its magnesium removal process ("demagging
process"), after application of the best
practicable control technology currently available:
There shall be no discharge of process wastewater
pollutants to navigable waters.
871
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - II
(c) The following limitations establish the quantity or
quality of pollutants or pollutant properties
controlled by this section, which may be discharged by
a point source subject to the provisions of this
subpart and which uses chlorine in its magnesium
removal process, after application of the best
practicable control technology currently available:
Effluent Limitations
Effluent Average of daily values for 30 consecutive
Characteristic days shall not exceed
Metric units (kilograms per 1,000 kg
magnesium removed)
English units (lbs per 1,000 lbs
magnesium removed)
TSS 175
COD 6. 5
pH Within the range of 7.5 to 9.0
872
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - II
(d) The following limitations establish the quantity or
quality of pollutants or pollutant properties which
may be discharged by a point source subject to the
provisions of this subpart and which processes residues
by wet methods, after application of the best
practical control technology currently available:
Effluent Limitations
Effluent Average of daily values for 30 consecutive
Characteristic days shall not exceed
Metric units (kilograms per 1,000 kg
of product removed)
English units (lbs per 1,000 lbs
of product removed)
TSS 1.5
Fluoride 0.4
Ammonia (as N) 0.01
Aluminum 1.0
Copper 0.00 3
COD 1.0
pH Within the range of 7.5 to 9.0
873
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - II
3. EPA is modifying BAT effluent limitations to take into
account the performance achievable by the application
of chemical precipitation, sedimentation, and
multimedia filtration (lime, settle, and filter)
technology, along with preliminary treatment consisting of
ammonia steam stripping and activated carbon adsorption for
selected waste streams. The following BAT effluent
limitations are promulgated for existing sources:
(a) Scrap Drying Wet Air Pollution Control
BAT EFFLUENT LIMITATIONS
Pollutant or
Pollutant Property
Maximum for
Any One Day
Maximum for
Monthly Average
Metric Units - mg/kg of aluminum scrap dried
English Units - lbs/million lbs of aluminum scrap dried
Lead
Zinc
Aluminum
Ammonia (as N)
0.000
0.000
0.000
0.000
0,
0,
0 ,
0.
000
000
000
000
(b) Scrap Screening and Milling
BAT EFFLUENT LIMITATIONS
Pollutant or
Pollutant Property
Maximum for
Any One Day
Maximum for
Monthly Average
Metric Units - mg/kg of aluminum scrap screened and milled
English Units - lbs/million lbs of aluminum scrap screened
and milled
Lead
Zinc
Aluminum
Ammonia (as
N)
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
874
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - II
(c) Dross Washing
BAT EFFLUENT LIMITATIONS
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of dross washed
English Units - lbs/million lbs of dross washed
Lead 3.043 1.413
Zinc 11.090 4.565
Aluminum 66.410 29.450
Ammonia (as N) 1,449.000 636.900
(d) Demagging Wet Air Pollution Control
BAT EFFLUENT LIMITATIONS
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum demagged
English Units - lbs/million lbs of aluminum demagged
Lead 0.216 0.100
Zinc 0.786 0.324
Aluminum 4.711 2.090
Ammonia (as N) 102.800 45.180
(e) Delacquering Wet Air Pollution Control
BAT EFFLUENT LIMITATIONS
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum delacquered
English Units - lbs/million lbs of aluminum delacquered
Lead 0.022 0.010
Zinc 0.082 0.034
Aluminum 0.489 0.217
Ammo nia(asN) 10.670 4.688
Total Phenols 0.001
(4-AAP Method)*
*At the source
875
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - II
(f) Direct Chill Casting Contact Cooling
BAT EFFLUENT LIMITATIONS
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum cast
English Units - lbs/million lbs of aluminum cast
Lead 0.372 0.173
Zinc 1.356 0.550
Aluminum 8.120 3.602
Ammonia (as N) 177.200 77.880
(g) Ingot Conveyer Casting Contact Cooling (When Chlorine
Demagging Wet Air Pollution Control is Not Fracticed On-
Site)
BAT EFFLUENT LIMITATIONS
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum cast
English Units - lbs/million lbs of aluminum cast
Lead 0.019 0.009
Zinc 0.068 0.028
Aluminum 0.409 0.182
Ammonia (as N) 8.931 3.926
(h) Ingot Conveyer Casting Contact Cooling (When Chlorine
Demagging Wet Air Pollution Control is Practiced On-
Site)
BAT EFFLUENT LIMITATIONS
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum cast
English Units - lbs/million lbs of aluminum cast
Lead 0.000 0.000
Zinc 0.000 0.000
Aluminum 0.000 0.000
Ammonia (as N) 0.000 0.000
876
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - II
(i) Stationary Casting Contact Cooling
BAT EFFLUENT LIMITATIONS
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum cast
English Units - lbs/million lbs of aluminum cast
Lead 0.000 0.000
Zinc 0.000 0.000
Aluminum 0.000 0.000
Ammonia (as N) 0.000 0.000
(j) Shot Casting Contact Cooling
BAT EFFLUENT LIMITATIONS
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum cast
English Units - lbs/million lbs of aluminum cast
Lead 0.000 0.000
Zinc 0.000 0.000
Aluminum 0.000 0.000
Ammonia (as N) 0.000 0.000
877
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - II
EPA is modifying NSPS based on the performance
achievable by the application of chemical
precipitation, sedimentation, and multimedia
filtration (lime, settle, and filter) technology, along
with preliminary treatment consisting of activated
carbon adsorption and oil skimming for selected
waste streams. The following effluent standards are
promulgated for new sources:
(a) Scrap Drying Wet Air Pollution Control
Pollutant or
Pollutant Property
Maximum for
Any One Day
NSPS
Maximum for
Monthly Average
Metric Units - mg/kg of aluminum scrap dried
English Units - lbs/million lbs of aluminum scrap dried
Lead
Zinc
Aluminum
Ammonia (as N)
Oil and Grease
TSS
pH
000
000
000
000
000
000
0-000
0.000
0.000
0.000
0.000
0 .000
Within the range of 7.0 to 10
at all times
878
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - II
(b) Scrap Screening and Milling NSPS
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum scrap screened and milled
English Units - lbs/million lbs of aluminum scrap screened
and milled
Lead 0.000 0.000
Zinc 0.000 0.000
Aluminum 0.000 0.000
Ammonia (as N) 0.000 0.000
Oil and Grease 0.000 0,000
TSS 0.000 0.000
pH Within the range of 7.0 to 10.0
at all times
(c) Dross Washing NSPS
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of dross washed
English Units - lbs/million lbs of dross washed
Lead 0.000 0.000
Zinc 0.000 0.000
Aluminum 0.000 0.000
Ammonia (as N) 0.000 0.000
Oil and Grease 0.000 0.000
TSS 0.000 0.000
pH Within the range of 7.0 to 10.0
at all times
(d) Demagging Wet Air Pollution Control NSPS
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum demagged
English Units - lbs/million lbs of aluminum demagged
Lead 0.216 0.100
Zinc 0.786 0.324
Aluminum 4.711 2.090
Ammonia (as N) 102.800 45.180
Oil and Grease 7.710 7.710
TSS 11.570 9.252
pH Within the range of 7.0 to 10.0
at all times
879
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - II
(e) Delacquering Wet Air Pollution Control NSPS
Pollutant or
Pollutant Property
Maximum
Any One
for
Day
Maximum for
Monthly Average
Metric Units - mg/kg of aluminum delacquered
English Units - lbs/million lbs of aluminum delacquered
Lead
Zinc
Aluminum
Ammonia (as N)
Total Phenols
(4-AAP Method)*
TSS
Oil and Grease
pH
0.022
0.082
0.489
10.670
0.001
1.200
0.800
0
0
0
4
010
034
217
688
0.960
0.800
Within the range of 7.0 to 10.0
at all times
*At the source
(f) Direct Chill Casting Contact Cooling NSPS
Pollutant or
Pollutant Property
Max imum
Any One
for
Day
Maximum for
Monthly Average
Metric Units - mg/kg of aluminum cast
English Units - lbs/million lbs of aluminum cast
Lead
Zinc
Alumi num
Ammonia (as
Oil and
TSS
pH
N)
Grease
0,
1,
8
177.
13,
19,
372
356
120
200
290
940
0
0
3
77
13
15
173
558
602
880
290
950
Within the range of 7.0 to 10.0
at all times
880
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - II
(g) Ingot Conveyer Casting Contact 'Cooling NSPS (When
Chlorine Demagging Wet Air Pollution Control is Not
Practiced On-site)
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum cast
English Units - lbs/million lbs of aluminum cast
Lead 0.019 0.009
Zinc 0.068 0.028
Aluminum 0.409 0.182
Ammonia (as N) 8.931 3.926
TSS 1.005 0.804
Oil and Grease 0.670 0.670
pH Within the range of 7.0 to 10.0
at all times
(h) Ingot Conveyer Casting Contact Cooling NSPS (When
Chlorine Demagging Wet Air Pollution Control is
Practiced On-Site)
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum cast
English Units - lbs/million lbs of aluminum cast
Lead 0.000 0.000
Zinc 0.000 0.000
Aluminum 0.000 0.000
Ammonia (as N) 0.000 0.000
TSS 0.000 0.000
Oil and Grease 0.000 0.000
pH Within the range of 7.0 to 10.0
at all times
881
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - II
(i) Stationary Casting Contact Cooling NSPS
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum cast
English Units - lbs/million lbs of aluminum cast
Lead 0.000 0.000
Zinc 0.000 0.000
Aluminum 0.000 0.000
Ammonia (as N) 0.000 0.000
Oil and Grease 0.000 0.000
TSS 0.000 0.000
pH Within the range of 7.0 to 10.0
at all times
(j) Shot Casting Contact Cooling NSPS
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum cast
English Units - lbs/million lbs of aluminum cast
Lead 0.000 0.000
Zinc 0.000 0.000
Aluminum 0.000 0.000
Ammonia (as N) 0.000 0.000
Oil and Grease 0.000 0.000
TSS 0.000 0.000
pH Within the range of 7.0 to 10.0
at all times
5. EPA is modifying PSES based on the performance achievable
by the application of chemical precipitation, sedimentation,
and multimedia filtration (lime, settle, and filter)
technology, along with preliminary treatment consisting of
ammonia steam stripping and activated carbon adsorption for
selected waste streams. The following mass-based
pretreatment standards are promulgated for existing sources:
862
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - II
(a) Scrap Drying Wet Air Pollution Control PSES
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum scrap dried
English Units - lbs/million lbs of aluminum scrap dried
Lead 0.000 0.000
Zinc 0.000 0.000
Ammonia (as N) 0.000 0.000
(b) Scrap Screening and Milling PSES
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum scrap screened and milled
English Units - lbs/million lbs of aluminum scrap screened
and milled
Lead 0.000 0.000
Zinc 0.000 0.000
Ammonia (as N) 0.000 0.000
(c) Dross Washing PSES
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of dross washed
English Units - lbs/million lbs of dross washed
Lead 3.043 1.413
Zinc 11.090 4.565
Ammonia (as N) 1,449.000 636.000
(d) Derr.agging Wet Air Pollution Control PSES
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum demagged
English Units - lbs/million lbs of aluminum demagged
Lead
Zinc
Ammonia (as N)
0.216
0.1
0.786
0.3
102.800
45 .1
883
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - II
(e) Delacquering Wet Air Pollution Control PSES
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum delacquered
English Units - lbs/million lbs of aluminum delacquered
Lead
0.
022
0
.010
Z inc
0.
082
0
. 034
Ammonia (as N)
10.
670
4
.688
Total Phenols
0.
001
--
(4-AAP Method)*
*At the source
(f) Direct Chill Casting Contact Cooling PSES
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum cast
English Units - lbs/billion lbs of aluminum cast
Lead 0.372 0.173
Zinc 1.356 0.558
Ammonia (as N) 177.200 77.800
(g) Ingot Conveyer Casting Contact Cooling PSES (When
Chlorine Demagging Wet Air Pollution Control is Not
Practiced On-site)
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum cast
English Units - lbs/million lbs of aluminum cast
Lead 0.019 0.009
Zinc 0.068 0.028
Ammonia (as N) 8.931 3.926
884
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - II
(h) Ingot Conveyer Casting Contact Cooling PSES (When
Chlorine Demagging Wet Air Pollution Control is
Practiced On-Site)
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum cast
English Units - lbs/million lbs of aluminum cast
Lead 0.000 0.000
Zinc 0.000 0.000
Ammonia (as N) 0.000 0.000
(i) Stationary Casting Contact Cooling PSES
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum cast
English Units - lbs/million lbs of aluminum cast
Lead 0.000 0.000
Zinc 0.000 0.000
Ammonia (as N) 0.000 0.000
(j) Shot Casting Contact Cooling PSES
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum cast
English Units - lbs/million lbs of aluminum cast
Lead 0.000 0.000
Zinc 0.000 0. 000
Ammonia (as N) 0.000 0.000
7. EPA is modifying PSNS based on the performance achievable
by the application of chemical precipitation, sedimentation,
and multimedia filtration (line, settle, and filter)
technology, along with preliminary treatment consisting of
activated carbon adsorption for the delacquering wet air
pollution control waste stream. The following mass-based
pretreatnent standards are promulgated for new sources:
885
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - II
(a) Scrap Drying Wet Air Pollution Control PSNS
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum scrap dried
English Units - lbs/million lbs of aluminum scrap dried
Lead 0.000 0.000
Zinc 0.000 0.000
Ammonia (as N) 0.000 0.000
(b) Scrap Screening and Milling PSNS
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum scrap screened and milled
English Units - lbs/million lbs of aluminum scrap screened
and milled
Lead 0.000 0.000
Zinc 0.000 0.000
Ammonia (as N) 0.000 0.000
(c) Dross Washing PSNS
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of dross washed
English Units - lbs/million lbs of dross washed
Lead 0.000 0.000
Zinc 0.000 0.000
Ammonia (as N) 0.000 0.000
(d) Demagging Wet Air Pollution Control PSNS
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kkg of aluminum demagged
English Units - lbs/billion lbs of aluminum denagged
Lead 0.216 0.100
Zinc 0.786 0.324
Ammonia (as N) 102.800 45.180
886
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - II
(e) Delacqaering Wet Air Pollution Control PSNS
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum delacquered
English Units - lbs/million lbs of aluminum delacquered
Lead 0.022 0.010
Zinc 0.082 0.034
Ammonia (as N) 10.670 4.688
Total Phenols 0.001
(4-AAP Method)*
*At the source
(f) Direct Chill Casting Contact Cooling PSNS
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum cast
English Units - lbs/million lbs of aluminum cast
Lead 0.372 0.173
Zinc 1.356 0.558
Ammonia (as N) 177.200 77.880
(g) Ingot Conveyer Casting Contact Cooling PSNS (When
Chlorine Demagging Wet Air Pollution Control is Not
Practiced On-Site)
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
mg/kg (lb/million lbs) of aluminum cast
Lead 0.019 0.009
Zinc 0.068 0.028
Ammonia (as N) 8.931 3.926
887
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - II
(h) Ingot Conveyer Casting Contact Cooling PSNS (When
Chlorine Demagging Wet Air Pollution Control is
Practiced On-Site)
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
mg/kg (lb/million lbs) of aluminum cast
Lead 0.000 0.000
Zinc 0.000 0.000
Ammonia (as N) 0.000 0.000
(i) Stationary Casting Contact Cooling PSNS
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum cast
English Units - lbs/million lbs of aluminum cast
Lead 0.000 0.000
Zinc 0.000 0.000
Ammonia (as N) 0.000 0.000
(j) Shot Casting Contact Cooling PSNS
Pollutant or Maximum for Maximum for
Pollutant Property Any One Day Monthly Average
Metric Units - mg/kg of aluminum cast
English Units - lbs/million lbs of aluminum cast
Lead
0.000
0 .000
Zinc
0.000
0 .000
Ammonia (as N)
0.000
0 . 000
888
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - III
SECTION III
INDUSTRY PROFILE
This section of the Secondary Aluminum Supplement describes the
raw materials and processes used in producing recycled aluminum
and presents a profile of the secondary aluminum plants
identified in this study.
DESCRIPTION OF SECONDARY ALUMINUM PRODUCTION
Secondary aluminum production involves two basic process steps:
pretreatment and smelting and refining. A pretreatment step is
required before smelting and refining operations can be under
taken because this industry uses scrap aluminum (much of which is
contaminated) for its raw material. The two processes, their
components, and variations are discussed below. Figure III-l
(page 898) represents a general flow diagram of the two process
steps.
RAW MATERIALS
The secondary aluminum subcategory uses aluminum-bearing scrap to
produce metallic aluminum and aluminum alloys. Much of the scrap
used is purchased from scrap dealers of industrial plants. There
are six primary classifications of scrap processed: aluminum
cans, old sheet and castings, new clippings and forgings, borings
and turnings, residues, and high iron.
New scrap is produced during the manufacture of a finished
product and originates from the aircraft industry, aluminum
formers, and other manufacturing plants. Old scrap (sheet and
castings) is comprised of worn out, damaged or obsolete articles
and includes automobile parts, household items, and airplane
parts. Borings and turnings are by-products of the machining of
castings, rods, and forgings by the aircraft and automobile
industry. Residues consist of drosses, skimmings, and slags which
are obtained from primary reduction plants, secondary smelting
plants, casting plants, and foundries. Foil from discarded
packaging constitutes a minor source of raw material for this
subcategory. High iron aluminum scrap which is to be reused in
the secondary aluminum subcategory require more extensive
treatment before smelting than other classificat ions scrap
aluminum,
PRELIMINARY TREATMENT
Preliminary treatment of scrap involves preparing the material
for further processing and removing contaminants. As Figure III-
1 (pace 898) indicates, the scrap pretreatment process varies
deoendir.c cn the source and type of raw material being handled.
There is also variation in the degree to which scrap is
pret rented arr.ong facilities. There are three general methods of
889
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - III
pretreating: mechanical, hydrometallurgical, and
pyrometallurgical, with the method used being dependent on the
type of scrap. The mechanical method involves shredding and
classifying, baling, and milling and screening.
Hydrometallurgical treatment involves leaching with water, and
pyrometallurgical processing involves burning and drying, and
sweating. Depending on the type of raw material, pretreatment
may consist of a combination of these methods before smelting and
refining is effected.
Old sheet, castings, and clippings preparation is a dry process
that can vary from no pretreatment to crushing and screening that
compacts the scrap. New clippings and forgings usually require
little preparation other than sorting; however, they may be
contaminated with cutting oils, and may require crushing and
drying to remove the oils. Can scrap is often pretreated by
burning the lacquer from the cans prior to smelting or rernelting.
Organic fumes emitted during this process are an air pollution
source. Wet scrubbers are normally chosen over afterburners and
baghouses to control emissions because of the explosion hazard
that exists. Cable, which is not considered a major source of
aluminum scrap requires shredding and classifying to remove the
insulation and ferrous portions from the aluminum. The borings
and burnings are also often contaminated by cutting oils and
require burning or drying to remove that contaminant. The entire
procedure consists of (1) crushing the borings and turnings to
compact the scrap, (2) heating the scrap in an oil or gas-fired
rotary dryer to remove organic material and water, (3) screening
to remove aluminum fines, and (4) magnetically removing the tramp
iron.
Aluminum and other metals from junked automobiles are recovered
in a water elutriator system where scrap auto body parts are
separated from light waste materials based on specific gravity
differences. Water, or other flotation media, flow upward and
separate the lightweight materials from the metal which continues
to sink. Metal collected at the bottom of the system is removed
with a perforated conveyer, and the water drains into a holding
tank for settling and then returns to the system.
Residues, such as drosses, skimmings, and slags, contain 10 to 30
percent aluminum, as well as oxides, carbides, nitrides, fluxing
salts, and other contaminants. Metallic aluminum can be
liberated from the impurities using either dry or wet processes.
The dry process consists of milling, screening, and magnetic
separation for iron removal. The wet process involves milling
and leaching with water to remove the contaminants. The washed
material is then screened, dried, and passed through a magnetic
separator. Heavy metallic skims, a minor source of aluminum,
require little pretreatment.
Foil, which is another minor source of raw material for the
subcategory, is usually pretreated by roasting to remove paper or
wax backings. High iron content scrap often is subjected to
sweating treatment to remove impurities. This process involves
890
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - III
placing the iron-contaminated aluminum in a sweating furnace.
This furnace has sloped sides and the molten aluminum flows down
the slope, leaving the higher melting point materials such as
iron behind. Alternately, the high iron scrap also can be
purified by crushing it and removing the iron magnetically.
SMELTING AND REFINING
The second step of the manufacturing process for the secondary
aluminum subcategory is smelting and refining. This step
actually consists of five substeps: charging scrap to the
furnace; addition of fluxing agents; addition of alloying agents;
demagging or degassing; and skimming.
Charging of scrap into the furnace can be a batch process or a
continuous process. Each cycle, called a "heat", will vary in
length depending on the process. Charging wells are often
designed to permit the introduction of chips and scrap below the
surface of a previously melted charge called a "heel." This
design not only minimizes oxidation, but provides for more
efficient application of pollution control systems.
The next step is fluxing the molten charge. There are two
general types of fluxes: cover fluxes that are used to reduce
oxidation of the melt by air, and solvent fluxes that react with
contaminants such as nonmetallics, residues from burned coatings,
and dirt to form insolubles which float on the surface of the
melt as slag.
Next, alloying agents are added to the melt in varying amounts
according to production specifications. Copper, silicon,
manganese, or zinc are typical alloys added. Mixing the furnace
contents is necessary to assure uniform composition. Nitrogen or
other inert gases may be injected to aid in the mixing.
Magnesium is another alloying agent used. However, scrap
aluminum, received by the secondary aluminum smelters averages
about 0.3 to 0.5 percent magnesium, while the product line of
alloys produced averages about 0.1 percent. Therefore, after the
furnace is fully charged and the melt brought up to the desired
chemical specification, it is usually necessary to remove the
excess magnesium (known as "demagging").
Demagging is accomplished with chlorine or chlorinating agents,
such as anyhdrous aluminum chloride or with aluminum fluoride.
Magnesium chloride or magnesium fluoride is formed and collected
in the fluxing agents on top of the molten melt. As the
magnesium is depleted, chlorine will consume aluminum and the
excess aluminum chloride or aluminum fluoride present volatilizes
into the surrounding air and is a source of air pollution.
Magnesium is the only metal removable from the alloy in this
manner. Other metal alloy levels must be adjusted by the
addition of either more aluminum (dilution) or more of the metal.
Chlorination is performed at temperatures between 760 and 815°C.
891
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - III
As a rule of thumb, the reaction requires 3.5 kilograms of
chlorine per kilogram of magnesium removed. Elemental chlorine
gas is fed under pressure through tubes or lances to the bottom
of the melt. As it bubbles through the melt, it reacts with
magnesium and aluminum to form chlorides, which float to the melt
surface where they combine with the fluxing agents and are
skimmed off. Because magnesium is above aluminum in the
electromotive series, aluminum chloride will be reduced by any
available magnesium in the melt. At the beginning of the
demagging cycle, the principal reaction product is magnesium
chloride. As magnesium is removed and there is less available
for reaction with chlorine, the reaction of chlorine with
aluminum becomes more significant, the reduction of the aluminum
chloride by magnesium becomes less likely, and the production of
aluminum chloride, a volatile compound, becomes significant. The
aluminum chloride escapes and considerable fuming results from
the chlorination, making ventilation and air pollution equipment
necessary. Control of fumes is frequently accomplished by wet
scrubbing and, thus, is a source of water contamination.
Aluminum fluoride as a demagging agent reacts with the magnesium
to form magnesium fluoride, which in turn combines with the flux
on top of the melt, where it is skimmed off. In practice, about
4.3 kilograms of aluminum fluoride are required per kilogram of
magnesium removed. The air contaminants exist as gaseous
fluorides or as fluoride dusts and are a source of air pollution.
The fluorides are controlled by either dry or wet methods. When
dry scrubbing is used, a solid waste is generated. When wet
scrubbing is used, both water pollution and solid waste are
generated.
Some facilities in the secondary aluminum subcategory are not
limited by a magnesium content in their product, particularly the
deoxidant manufacturers, and they make no attempt to remove
magnesium. Therefore, these plants do not generate the magnitude
of fumes produced by demagging, and as a result, do not require
extensive air pollution control equipment and related water
usage.
In the skimming step, the dross or slag, with its associated
impurities, is skimmed from the molten aluminum. The cooled slag
is stored for shipment to a residue processor, recycled, or
discarded.
The product line(s) of each smelter can be categorized as
specification alloy ingots, billets, hot metal, notched bar,
shot, and hardeners. Specification alloy ingots, used by
foundries for casting, are the most important products of the
secondary aluminum subcategory. Cooling can be done with either
contact or noncontact cooling water, and air cooling is also
used. Ingot conveyer casting is the most predominant casting
method used in the secondary aluminum subcategory. Molten
aluminum is poured into ingot molds traveling on a conveyer
system. The aluminum is allowed to briefly air cool prior to
contacting the metal surface and mold with water. This allows
892
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - III
the metal surface to solidify so that the aluminum surfaces are
not water marked. Enough heat is extracted from the aluminum for
solidification and to prevent breaking when the aluminum is
removed from the mold. Notched bar, RAI, and redox casting are
three variations of ingot conveyer casting.
Direct chill casting is characterized by continuous
solidification of the metal while it is being poured. The
length of an ingot cast using this method is determined by the
vertical distance it is allowed to drop rather than by mold
dimensions. Molten aluminum is tapped from the melting furnace
and flows through a distributor channel into a shallow mold.
Noncontact cooling water circulates within this mold, causing
solidification of the aluminum. The base of the mold is attached
to a hydraulic cylinder which is gradually lowered as pouring
continues. As the solidified aluminum leaves the mold, it is
sprayed with contact cooling water to reduce the temperature of
the forming ingot. The cylinder continues to descend into a tank
of water, causing further cooling of the ingot as it is immersed.
When the cylinder has reached its lowest position, pouring stops
and the ingot is lifted from the pit. The hydraulic cylinder is
then raised and positioned for another casting cycle.
Plants using contact cooling water recycle systems generate
intermittent discharges (accompanied with sludge removal).
Billets, manufactured for use in extrusion plants, are cooled
with noncontact water that is recycled. Sometimes the molten
metal is poured directly into preheated crucibles, then shipped
while still in a molten form. No water is used. Notched bar
molds may be air or water cooled with either contact or
noncontact water.
Aluminum shot is also used as a deoxidant in the steel industry.
Molten metal is poured into a vibrating feeder, where droplets of
molten metal are formed through perforated openings. The
droplets are cooled in a quench tank. Water is generally
recycled, and periodic sludge removal is required.
PROCESS WASTEWATER SOURCES
The primary areas of water use and wastewater production in the
secondary aluminum subcategory are as follows:
1. Scrap drying wet air pollution control,
2. Scrap screening and milling,
3. Dross washing,
4. Demagging wet air pollution control,
5. Delacquering wet air pollution control,
6. Direct chill casting contact cooling water
7. Ingot conveyer casting contact cooling,
casting contact cooling water, and 9. Shot
cooling water.
8. Stationary
casting contact
893
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - III
OTHER WASTEWATER SOURCES
There are other wastewater streams associated with the production
of secondary aluminum. These include but are not limited to:
1. Maintenance and cleanup water, and
2. Stormwater runoff.
These wastewaters are not considered as part of this rulemaking.
EPA believes that the flows and pollutant loadings associated
with these streams are insignificant relative to the wastewater
streams selected, or are best handled by the appropriate permit
authority on a case-by-case basis under the authority of Section
402 of the CWA.
AGE, PRODUCTION, AND PROCESS PROFILE
Figure III-2 (page 899) shows the location of 47 secondary
aluminum reduction plants. Most of the. plants are located in the
eastern United States, and most are in urban areas near raw
materials and markets. The notations within the states indicated
the type of discharge the facilities use, direct (D), indirect
(I), or zero (Z).
The data in Table III-l (page 895) indicate that the majority of
facilities (34) are less than 35 years old, reflecting the
relatively recent development of this industry.
In addition, most facilities practice zero discharge with only 21
percent (10 facilities) discharging directly to waters of the U.S.
The data in Table III-2 (page 896) indicate that the majority of
facilities produce between 5,000 and 20,000 kkg per year of
secondary aluminum. Table III-3 (page 897) provides a summary of
the plants having the various secondary aluminum processes; the
number of plants generating wastewater from the processes is also
shown.
894
-------
Table 111-1
INITIAL OPERATING YEAR (RANGE) SUMMARY OK PLANTS
IN THE SECONDARY AIJJM1NIM SUBCATEGORY BY DISCHARGE TYPE
Type of 1983- 1973-
Plant 1974 1969
Discharge 0-10 10-15
Direct
Indirect
Zero
00
VO
U1
Total
1968-
1959
15-25
15
1958-
1949
25-35
1948-
1939
35-45
1938-
1929
45-55
1928-
1919
55-65
1918-
'1904
65-80
Before
1904
80+
0
0
Insuff.
Data
1
0
Total
10
14
23
47
w
M
O
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55
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s
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3
M
<=:
s
w
<=:
w
o
>
H
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O
O
K
to
M
O
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - III
TABLE II1-2
PRODUCTION RANGES FOR SMELTERS AND REFINERS
OF THE SECONDARY ALUMINUM SUBCATEGORY
(kkg/yr)
Production Ranges Number of Plants
0 - 2500 4
2501 - 5000 4
5001 - 10000 16
10000 - 20000 8
20001 - 30000 3
30000 - + 3
No Data 6
Total Number of 47
Plants in Survey
896
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - III
TABLE II1-3
SUMMARY OF SUBCATEGORY PROCESSES AND ASSOCIATED WASTE STREAMS
Process
Raw Material Preparation
Number of
Plants With
Process
Scrap drying air pollution 23
cont rol
Scrap screening and milling 18
Dross washing 3
Dust air pollution control 13
Delacquering 5
air pollution control 5
Number of Plants
Generating
Wastewater
1
3
0
Demagging
air pollution control
Casting
Ingot conveyer casting
Shot casting
17
40
14
4
17
14
4
897
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - I
RDCVS2 t«ON
i 5M^o?iwc :cj»cfcn:si
^ Fiyts
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irvruDurjii
fUtAACE
m,o n KLTtr.i ;¦ -uatkdtt
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.-aST'SC
roc-Li*:.
SNIP "CLTLt AiL>llH,?1 SHIP ALL^IfL'** 1NMT5
Figure 111- 1
SECONDARY ALUMINUM SMELTING PROCESS
898
-------
N DAK
S DAM
7
NTI1R
rams
rmih
M ias
c
f"
AlA$KA
t Process Wastewater Discharge Plants
I-Tndirect Wastewater Discharge. Plants
Z-Zero Wastewater Discharge Plants
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Figure 111-2
GEOGRAPHIC LOCATIONS OF SECONDARY ALUMLNUM PLANTS
-------
SECONDARY*ALUMINUM SUBCATEGORY SECT - IV
SECTION IV
SUBCATEGORIZATION
This section summarizes the factors considered during the
designation of the secondary aluminum subcategory and its related
subdivisions, Secondary aluminum was identified as a subcategory
in a final regulation promulgated in 1974 and BPT, BAT, NSPS, and
PSNS effluent limitations and standards were established for the
secondary aluminum subcategory. The purpose of this study is to
support modifications to the BAT, NSPS, and PSNS regulations.
FACTORS CONSIDERED IN SUBDIVIDING THE SECONDARY ALUMINUM
SUBCATEGORY
The factors for general subcategorization were each evaluated
when establishing the secondary aluminum subcategory and its
subdivisions. In the discussion that follows, the factors will
be described as they pertain to this particular subcategory.
Subcategorization of the entire nonferrous metals industry and
evaluation of the factors used in this process are discussed in
Section IV of the General Development Document.
The rationale for dividing the secondary aluminum subcategory
into segments or building blocks considers the diversity in
source of raw materials, the use of certain manufacturing
processes by only a few facilities, and the differences in
available technologies for final product processing (i.e.,
contact cooling water, air cooling, and noncontact cooling
water).
The raw materials used by secondary aluminum plants are either
solid scraps (clippings and forgings, borings and turnings, and
old sheet and castings) or residues from aluminum reduction and
smelting. Since all secondary smelters use the various types of
scraps at one time or another, the type of scrap cannot be used
as a basis for subcategorization. However, many plants have
scrap drying operations. Most of these plants use air pollution
control devices in this process. A few plants use wet scrubbers
which produce wastewater. Some facilities also use water in
scrap screening and milling, generating wastewater. Therefore,
scrap drying wet air pollution control and scrap screening and
milling should be considered segments.
Can scrap is normally heated prior to melting to burn the lacquer
contained on the cans. Wet scrubbers are normally used to
control air pollution rather than afterburners and baghouses
because of the explosion hazard. Explosion potential is
increased if the scrap is shredded due to aluminum fines that
would collect in dry scrubbing systems. Five plants operate wet
scrubbers, indicating that delacquering wet air pollution control
should be considered a segment.
901
Preceding page blank
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - IV
Furnace residue processing to recover aluminum can produce a
wastewater stream with treatable pollutant concentrations. Five
facilities process furnace residues, and four of these use water
for the processing. Since this process produces a potentially
contaminated waste stream it has been identified as a segment.
Plants practicing magnesium removal (demagging), use either a
chlorine or aluminum fluoride process. The demagging process
requires air pollution control devices to minimize fuming. Wet
scrubbing can be practiced with both types of demagging and the
resulting scrubber water is usually treated by pH adjustment and
settling.
Thirty-four plants demag, 20 generate wastewater from fume
scrubbing. Because the demagging process can produce a
contaminated wastewater, it has been identified as a segment
within the secondary aluminum subcategory.
The final secondary aluminum process step is casting. The
technique for cooling the aluminum into various shapes varies
within the subcategory and with the product. Air cooling, water
contact cooling, and water noncontact cooling are all used. When
water contact cooling is used, the cooling water is frequently
recycled. However, a blowdown stream may be necessary to
dissipate the build-up of dissolved solids. This blowdown stream
may have, in addition to treatable dissolved solids, oil and
grease and phenolics, depending on whether lubricants are used in
casting. This manufacturing process has also been considered to
be segment within the secondary aluminum subcategory.
Within the secondary aluminum subcategory the processes that
produce the wastewaters discussed previously, residue processing
wastewater, demagging fume scrubber liquors, and contact cooling
water, are not all present at all facilities. Some facilities
may have one, others combinations of two, and still others all
three. The building block approach used in this regulation
accommodates these differences by establishing limitations and
standards for each wastewater stream.
Limitations will be based on specific flow allowances for the
following subdivisions:
1. Scrap drying wet air pollution control,
2. Scrap screening and milling,
3. Dross washing,
4. Demagging wet air pollution control,
5. Delacquering wet air pollution control,
6. Ingot conveyer casting,
7. Direct chill casting contact coding,
8. Stationary casting contact cooling, and
9. Shot casting contact cooling.
902
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - IV
OTHER FACTORS
The other factors consi
inappropriate bases f
control methods, treat
total energy requiremen
selected subcategoriz
materials, and product
method of subcategori
other factors, such as
employees, were also ev
as bases for subcategor
dered in this evaluation were shown to be
or further segmentation. Air pollution
ment costs, nonwater quality aspects, and
ts were each shown to be functions of the
ation factors — metal product, raw
ion processes. As such, they support the
zation which has been applied. Certain
plant age, plant size, and the number of
aluated and determined to be inappropriate
ization of nonferrous metal plants.
PRODUCTION NORMALIZING PARAMETERS
The effluent limitations and standards developed in this document
establish mass limitations on the discharge of specific pollutant
parameters. To allow these regulations to be applied to plants
with various production capacities, the mass of pollutant
discharged must be related to a unit of production. This factor,
the production normalizing parameter (PNP), is developed for each
segment in conjunction with subcategorization.
In general, the amount of aluminum processed or produced by the
respective manufacturing process segments is used as the PNP.
The PNP's for the nine secondary aluminum segments are:
Segment
Scrap drying wet air pollution
cont rol
Scrap screening and milling
3. Dross washing
4. Demagging wet air pollution
control
5. Delacquering wet air pollution
control
6. Ingot conveyer casting contact
cooling
7. Direct chill casting contact
cooling
8. Stationary casting contact
cooling
9. Shot casting contact cooling
PNP
kkg of aluminum scrap
dr ied
kkg of scrap screened or
milled
kkg of dross washed
kkg of aluminum demagged
kkg of aluminum
delacquered
kkg of aluminum cast
kkg of aluminum cast
kkg of aluminum cast
kkg of aluminum cast
903
-------
SECONDARY ALUMINUM SUBCATEGORY
SECT - IV
THIS PAGE INTENTIONALLY LEFT BLANK
9 C 4
-------
SECONDARY ALUMINUM SUBCATEGORY SECT -V
SECTION V
WATER USE AND WASTEWATER CHARACTERISTICS
This section describes the characteristics of wastewater
associated with the secondary aluminum subcategory. Data used to
quantify wastewater flow and pollutant concentrations are
presented, summarized, and discussed. The contribution of
specific production processes to the overall wastewater discharge
from secondary aluminum plants is identified whenever possible.
Two principal data sources were used in the development of the
effluent limitations and standards for this subcategory; data
collection portfolio (dcp) responses and field sampling results.
Data collection portfolios, completed for each of the secondary
aluminum plants, contained information regarding wastewater flows
and production levels. An additional source of data used in this
document is information and data gathered through comments and
Section 308 requests (used to obtain supporting documentation for
the comments). Additional data were gathered from six plants not
considered at proposal.
Since gathering dcp information for this subcategory, the Agency
has learned that 15 plants have closed. EPA believes that the
data from these plants provide useful measures of the
relationship between production and discharge. In light of this
conclusion, the Agency is using these data in its consideration
of BPT and BAT performance.
In order to quantify the pollutant discharge from secondary
aluminum plants, a field sampling program was conducted. A
complete list of the pollutants considered and a summary of the
techniques used in sampling and laboratory analyses have been
presented previously. samples were collected in two phases:
screening and verification. The first phase, screen sampling,
was to identify which toxic pollutants were present in the
wastewaters from production of the various metals. Screening
samples were analyzed for 128 of the 129 toxic pollutants and
other pollutants deemed appropriate. (Because the analytical
standard for TCDD was judged to be too hazardous to be made
generally available, samples were never analyzed for this
pollutant. There is no reason to expect that TCDD would be
present in secondary aluminum wastewater.) A total of 10 plants
were selected for screening sampling in the nonferrous metals
manufacturing category, one of those being a secondary aluminum
plant.
In general, the samples were analyzed for three classes of
pollutants: toxic organic pollutants, toxic metal pollutants,
and criteria pollutants (which includes conventional and
noncor.vent ional pol lutants ) .
As described in Section IV of this supplement, secondary aluminum
905
-------
SECONDARY ALUMINUM SUBCATEGORY SECT -V
plants have been categorized into nine segments. Differences in
the wastewater characteristics associated with these building
blocks are to be expected. For this reason, wastewater streams
corresponding to each segment are addressed separately in the
discussions that follow.
WASTEWATER SOURCES, DISCHARGE RATES, AND CHARACTERISTICS
The wastewater data presented in this section were evaluated in
light of production process information compiled during this
study. As a result, it was possible to identify the principal
wastewater sources in the secondary aluminum subcategory. The
result of this analysis is summarized in the following
discussion.
Sources of process wastewater within the secondary aluminum
subcategory include:
1. Scrap drying wet air pollution control,
2. Scrap screening and milling,
3. Dross washing,
4. Demagging wet air pollution control,
5. Delacquering wet air pollution control,
6. Ingot conveyer casting contact cooling,
7. Direct chill casting contact cooling water,
8. Stationary casting contact cooling, and
9. Shot casting contact cooling.
Data supplied by data collection portfolio responses were
evaluated, and two flow-to-production ratios were calculated for
each stream. The two ratios, water use and wastewater discharge
flow, were differentiated by the flow value used in calculation.
Water use was defined as the volume of water or other fluid
(e.g., emulsions, lubricants) required for a given process per
mass of aluminum product and was therefore based on the sum of
recycle and make-up flows to a given process. Wastewater flow
discharged after pretreatment or recycle (if these are used) was
used in calculating the production normalized flow -- the volume
of wastewater discharged from a given process to further
treatment, disposal, or discharge per mass of aluminum produced.
Differences between the water use and wastewater flows associated
with a given stream resulted from recycle, evaporation, and
carry-over on the product. The production values in calculations
correspond to the production normalizing parameter, PNP, assigned
to each stream, as outlined in Section IV. The production
normalized flows were compiled by stream type. Where
appropriate, an attempt was made to identify factors that could
account for variations in water use. This information is
.summarized in this section. A similar analysis of factors
affecting the wastewater values is presented in Sections X, XI,
and XII, where representative BAT, BDT, and pretreatment
discharge flows are selected for use in calculating the effluent
limitations and standards. As an example, casting cooling water
wastewater flow is related to the casting production. As such,
the discharge rate is expressed in liters of cooling water per
906
-------
SECONDARY ALUMINUM SUBCATEGORY SECT -V
metric ton of casting production (gallons of cooling water
wastewater per ton of aluminum reduction production).
In order to quantify the concentrations of pollutants present in
wastewater from secondary aluminum plants, wastewater samples
were collected at five plants. Diagrams indicating the sampling
sites and contributing production processes are shown in Figures
V-l to V-5 (pages 938 - 942)
The reported water use and discharge rates for the nine
identified secondary aluminum wet operations are given in Tables
V-l, 2, 3, 5, 7, 8, and 9 (pages 912 to 925). The raw wastewater
sampling data for the facilities sampled are presented in Tables
V-4, V-6, and V-10 (pages 915, 919, and 926). Table V-ll (page
927) shows combined raw wastewater data from demagging scrubbing
and casting contact cooling.
The treated wastewater data are shown in Tables V-12 through V-15
(pages 929 through 936). The locations and stream codes of the
samples taken are identified on the process flow diagrams in
Figures V-l through V-5 (pages 938 through 942). Where no data
is listed for a specific day of sampling, the wastewater samples
for the stream were not collected. If the analysis did not
detect a pollutant in a waste stream, the pollutant was omitted
from the table.
The data tables include some samples measured at concentrations
considered not quantifiable. The base neutral extractable, acid
extractable, and volatile organics are considered not
quantifiable at concentrations equal to or less than 0.010 mg/1.
Below this concentration, organic analytical results are not
quantitatively accurate; however, the analyses are useful to
indicate the possible presence of a particular pollutant. The
pesticide fraction is considered not quantifiable at
concentrations equal to or less than 0.005 mg/1. Nonquantifiable
results are designated in the tables with an asterisk (double
asterisk for pesticides).
These detection limits shown on the data tables are not the same
as published detection limits for these pollutants by the same
analytical methods. The detection limits used were reported with
the analytical data and hence are the appropriate limits to apply
to the data. Detection limit variation can occur as a result of
a number of laboratory-specific, equipment-specific, and daily
operator-specific factors. These factors can include day-to-day
differences in machine calibration, variation in stock solutions,
and variation in operators.
The statistical analysis of data includes some samples measured
at concentrations considered not quantifiable. Data reported as
an asterisk are considered as detected but below quantifiable
concentrations, and a value of zero is used for averaging. Toxic
organic, nonconventional and conventional pollutant data reported
with a "less than" sign are considered as detected, but not
further quantifiable. A value of zero is also used for
907
-------
SECONDARY ALUMINUM SUBCATEGORY SECT -V
averaging. If a pollutant is reported as not detected, it is
excluded in calculating the average. Finally, toxic metal
values reported as less than a certain value were considered at
not detected, and a value of zero is used in the calculation of
the average. For example, three samples reported as ND, *, and
0.021 mg/1 have an average value of 0.010 mg/1.
In the following discussion, water use and field sampling data
are presented for each operation. Appropriate tubing or
background blank and source water concentrations are presented
with the summaries of the sampling data. Figures V-l through V-5
(pages 938 through 942) show the location of wastewater sampling
sites at each facility. The method by which each sample was
collected is indicated by number, as follows:
1 one-time grab
2 24-hour manual composite
3 24-hour automatic composite
4 48-hour manual composite
5 48-hour automatic composite
6 72-hour manual composite
7 7 2-hour automatic composite
In the data collection portfolios, plants were asked to specify
the presence or absence of any of the toxic pollutants in their
effluent. All of the plants that responded to this portion of
the questionnaire indicated that they believed the toxic organic
pollutants to be absent. One exception, hexachloroethane, was
reported believed to be present by two plants. This compound was
not detected in any sample taken in the subcategory.
Although most of the plants indicated that the toxic metals were
believed absent from their effluent, some plants did report that
specific pollutants were known present or believed present. The
responses for the toxic metals are shown in the tabulation below.
Pollutant
Known
Present
Believed Believed
Present Absent
Known
Absent
Ant imony
Arsenic
Beryllium
Cadmium
Chromium
Copper
Lead
Mercury
Nickel
Selenium
Thai1ium
Z inc
1
5
11
1
7
2
5
9
6
6
2
2
1
5
1
23
22
22
17
7
21
10
18
16
22
22
8
1
1
1
9 C 8
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SECONDARY ALUMINUM SUBCATEGORY SECT -V
SCRAP DRYING WET AIR POLLUTION CONTROL
Some scrap may require drying to remove cutting oils and water.
The scrap drying procedure consists of crushing the scrap and
heating in an oil or gas-fired rotary drier. Explosions are
possible in the melting furnace if the scrap is not completely
dried prior to charging. Twenty-nine secondary aluminum plants
control air emissions from scrap drying operations. Three plants
reported the use of scrubbers, while 26 used baghouses. Scrap
drying wet air pollution control water use and discharge rates
are shown in Table V-l (page 912) in liters per metric ton
(gal/ton) of aluminum scrap dried. Plants 427 and 4102 have
either installed a dry system or discontinued the use of the
scrubber, and plant 640 has ceased operations.
The Agency did not sample raw wastewater from scrap drying
scrubbers, however, this wastewater should contain total
suspended solids and treatable concentrations of aluminum. Toxic
organic pollutants should not be present at measurable
concentrations.
SCRAP SCREENING AND MILLING
Only two plants reported using water in scrap screening and
milling. The discharge rates from these plants are presented in
Table V-2 (page 913) in liters per metric ton of aluminum scrap
screened or milled. The Agency did not sample scrap screening
and milling wastewater but this waste stream should contain total
suspended solids and treatable concentrations of aluminum, as
well as toxic metals.
. DROSS WASHING WASTEWATER
Sources of aluminum for the secondary aluminum subcategory are
residues such as drosses, skimmings, and slags. These residues
must be pretreated before charging them into the smelters. Both
wet and dry processes are available for this pretreatment. Of
the facilities surveyed, four used the wet process to prepare
their residues for smelting. The quantities of water used and
discharged, expressed as a function of dross processed, are
presented in Table V-3 (page 914).
The data in Table V-4 (page 915) indicate that this wastewater
contains treatable concentrations of suspended solids (aluminum
oxide and hydrated alumina), ammonia, and metals such as
aluminum, copper, and lead.
DEMAGGING WET AIR POLLUTION CONTROL
As discussed in Section III, demagging consists of injecting
chlorine or aluminum fluoride into the molten aluminum to remove
magnesium. During this process, heavy fuming can result. Of the
26 facilities supplying data, 17 reported using a wet process to
control emissions from this process, while nine reported using a
dry process. The flow rates used and discharged, expressed in
909
-------
SECONDARY ALUMINUM SUBCATEGORY SECT -V
liters/metric ton of aluminum demagged, for those plants with wet
air pollution control are shown in Table V-5 (page 918).
The wastewaters associated with this scrubbing operation may
contain treatable concentrations of suspended solids and
chlorides or fluorides, and of heavy metals. Table V-6 (page
919) summarizes the wastewater sampling data associated with
demagging scrubber wastes.
DELACQUERING WET AIR POLLUTION CONTROL
Five plants reported using wet scrubbers to control air pollution
from delacquering operations. Aluminum can scrap is charged to a
furnace where paint and lacquers are burned from the metal
surface. Aluminum fines emitted during shredding prior to
delacquering may also be controlled by the delacquering scrubber.
Delacquering wet air pollution control water use and discharge
rates are shown in Table V-7 (page 923) in liters per metric ton
(gal/ton) of aluminum delacquered.
Analytical data supplied to the Agency show treatable
concentrations of total phenolics (0.346 mg/1 to 26.8 mg/l)f
suspended solids (9 mg/1 to 60.8 mg/1), and the presence of zinc,
lead, and copper. Zinc was reported in treatable concentrations
in three of five samples with one sample reported as 7.3 mg/1.
GC/MS data supplied to the Agency show phenol, isophorone,
naphthalene, and phenanthrene at 5.4, 0.045, 0.011, and 0.012
mg/1, respectively. The remaining toxic organics were all
reported at less than 0.010 mg/1.
INGOT CONVEYER CASTING
The predominant method of casting in the secondary aluminum
subcategory is ingot conveyer casting. There are 17 reported
plants in the Agency's data base that use contact cooling water
in ingot conveyer casting. There are additional plants that may
use ingot conveyer casting; however, noncontact cooling water is
used. Water use and discharge rates obtained from the dcp are
presented in Table V-8. Three plants reported recycling cooling
water, while 14 plants indicated they do not incorporate any
recycle. One plant reported using ingot conveyer casting contact
cooling water as demagging scrubber liquor makeup.
Table V-10 presents casting contact cooling water sampling data
from a secondary aluminum plant utilizing ingot conveyer casting.
Extensive sampling data of direct chill casting is presented in
the aluminum forming point source category development document.
These data, which are not expected to be significantly different
than ingot conveyer casting, indicate suspended solids, oil and
grease, and toxic metals may be present in both types of cooling
waters.
DIRECT CHILL CASTING CONTACT COOLING WATER
The Agency is unaware of any secondary aluminum plants in the
910
-------
SECONDARY ALUMINUM SUBCATEGORY SECT -V
United States using direct chill casting. There are, however,
several plants that remelt aluminum scrap for forming operations
that use direct chill casting. Casting of aluminum scrap for use
in a forming plant is covered by the aluminum forming point
source category. Water use and discharge rates for direct chill
casting are presented in Section V of the primary aluminum
subcategory supplement.
SHOT CASTING CONTACT COOLING WATER
Four secondary aluminum plants reported casting shot for
subsequent use as a deoxidizer in the iron and steel industry.
Water use and discharge rates for shot casting are presented in
Table V-9. Temperature of the cooling water severely affects the
quality of the aluminum shot. It is reported that the
temperature of the quench bath must be maintained between 80F and
85F in the inlet and the outlet. Temperatures should not exceed
105F. Two plants used fresh make-up water to maintain the
correct temperature. The other two plants, however, reported
using cooling towers with no blowdown. Pollutant loadings of
shot casting contact cooling water are expected to be very
similar to ingot conveyer casting and direct chill casting, since
all of these processes use water to cool and cast the molten
metal. Oil and grease should not be present because mold
lubrication is not required for shot casting.
STATIONARY CASTING COOLING
In the stationary casting method, molten aluminum is poured into
cast iron molds and the generally allowed to air cool. The
Agency is aware of the use of spray quenching to quickly cool the
surface of the molten aluminum once it is cast into the molds;
however, this water evaporates on contact with the molten
aluminum. This operation is similar throughout the secondary
aluminum and primary aluminum subcategories, and the aluminum
forming category, and no discharge of process water has been
reported.
911
-------
SECONDARY ALUMINUM SUBCATEGORY SECT -V
TABLE V-l
WATER USE AND DISCHARGE RATES FOR
SCRAP DRYING WET AIR POLLUTION CONTROL
(1/kkg of aluminum scrap dried)
Production Production
Percent Normalized Normalized
Plant Code Recycle Water Use Discharge Rate
00427
0
1057
1057
04102
100
5111
0
00640
100
567 . 6
0
912
-------
SECONDARY ALUMINUM SUBCATEGORY SECT -V
TABLE V-2
WATER USE AND DISCHARGE RATES FOR
SCRAP SCREENING AND MILLING
(1/kkg of aluminum scrap dried)
Plant Code
00296
00301*
Percent
Recycle
100
100
Production
Normalized
Water Use
13B27
NR
Production
Normalized
Discharge Rate
0
0
* — HEAVY MEDIA SEPARATION
NR — DATA NOT REPORTED
913
-------
SECONDARY ALUMINUM SUBCATEGORY SECT -V
TABLE V-3
WATER USE AND DISCHARGE RATES FOR
DROSS WASHING
(1/kkg of dross washed)
Production Production
Percent Normalized Normalized
Plant Code Recycle Water Use Discharge Rate
04104
67
32993
10868
04101
100
78840
0
04102
100
58408
0
04103
67*
NR
0
* — Wastewater is all evaporated
NR -- Data not reported
914
-------
Table V-4
SECONDARY ALUMINUM SAMPLING DATA
DROSS WASHING
RAW WASTEWATER
vo
(_n
Pollutant (a)
Toxic Pollutants
Concentrations (mg/1, except as noted)
Stream Sample
Code Type + Source Day__L Day 2 Day 3 Average
23.
chloroform
70
2
0.022
0.061
0.057
0.059
30.
1 ,2-trans-dichloro-
ethy lene
70
2
ND
0.058
0.057
0.0575
39.
fluoranthene
70
3
~
0.02
0.02
66.
bis(2-ethylhexyl)
phthalate
70
3
0.038
2.03
2.03
67.
butyl benzyl
phthalate
70
3
ND
0.098
0.098
00
•
di-n-buty1
phthalate
70
3
~
0.022
0.022
69.
di-n-octyl
phthalate
70
3
0.011
0.036
0.036
71.
dimethyl phthalate
70
3
ND
0.056
0.056
76.
chrysene
70
3
~
0.1 98
0.1 98
•
00
tri chloroethylene
70
2
0.022
<0.021
<0.015
<0.018
115.
arsen ic
70
3
<0.01
0.02
0.02
117.
bery11ium
70
3
<0.001
0.05
0.05
c/i
M
O
O
55
o
>
w
K
>
t"1
C
s
M
55
c
3
in
c:
w
o
>
1-3
M
Q
O
»
K
W
m
0
1-3
1
<
-------
Table V-4 (Continued)
SECONDARY ALUMINUM SAMPLING DATA
DROSS WASHING
RAW WASTEWATER
Stream Sample
Concentrations (mg/I, except as noted)
I-*
cn
Pollutant
Code
Type
+ Source Day 1
Day 2
Day 3 Average
118.
cadmium
70
3
0.02 0.40
0.4
1 19.
chromium
70
3
0.009 2.0
2.0
1 20.
copper
70
3
0.02 10.0
10.0
1 22.
lead
70
3
<0.02 8.0
8.0
1 23.
mercury
70
3
<0.0001 0.0006
0.0006
1 24.
nickel
70
3
<0.005 1.0
1 .0
1 26.
s ilver
70
3
<0.02 0.07
0.07
1 27.
thallium
70
3
<0.01 1.0
1 .0
1 28.
zinc
70
3
<0.06 8.0
8.0
Nonconventionals
aluminum
70
3
0.05 2,000
2,000
ammonia
70
2
240
1 50
195.0
chemical oxygen
demand (COD)
70
3
933
933
phenols (total; by
4-AAP method)
70
2
0.006
0.016
0.01 1
total organic
carbon (TOC)
70
3
220
220.0
Ui
w
n
O
2:
o
>
50
K
>
G
3
M
2:
G
3
W
G
CO
n
>
t-3
W
-------
Table V-4 (Continued)
SECONDARY ALUMINUM SAMPLING DATA
DROSS WASHING
RAW WASTEWATER
M
Pollutant
Convent ionaIs
oil and grease
total suspended
solids (TSS)
pH (standard units)
Concentrations (mg/1, except as noted)
Stream Sample
Code Type + Source
70
70
70
2
2
1
Day 1
20.0
20.140
Day 2 Day 3
29.0
9.6
Average
24.50
20.140
(a) No samples were analyzed for the acid extractable toxic organic pollutants. One
sample was analyzed for the pesticide fraction; none was detected above its
analytical quantification limit. One sample was analyzed for PCBs; none was
detected.
+Sample Type. Note: These numbers also apply to subsequent sampling data tables
in this section.
1 - one-time grab
2 - 24-hour manual composite
3 - 24-hour automatic composite
4 - 48-hour manual composite
5 - 48-hour automatic composite
6 - 72-hour manual composite
7 - 72-hour automatic composite
in
pi
o
O
55
O
>
w
K
>
tr1
<=:
2
M
55
C
2
(/>
C
(I)
o
>
H
M
O
O
W
K
W
M
O
H
* Indicates less than or
** Indicates less than or
equal to 0.01 mg/1
equal to 0.005 mg/1
-------
SECONDARY ALUMINUM SUBCATEGORY SECT -V
TABLE V-5
WATER USE AND DISCHARGE RATES FOR
DEMAGGING WET AIR POLLUTION CONTROL
(1/kkg of aluminum demagged)
Production Production
Percent Normalized Normalized
Plant Code Recycle Water Use Discharge Rat
296
100
43059
0
4104
0
6885
6885
332
0
1867
1867
532
100
1740
0
37
0
1289
1289
660
86.9
997
131
330
0
680
680
4209
0
596
596
320
NR
547
547
329
0
518
518
48
28.6
456
326
427
0
447
447
333
0
361
361
313
0
313
313
628
0
283
283
326
0
223
223
6202
100
132
0
313
0
NR
NR
319
NR
NR
NR
625
0
NR
NR
— Data not reported
918
-------
Table V-6
S ECONDARY ALUMINUM SAMPLING DATA
DEMAGGING SCRUBKER LIQUOR
RAW WASTEWATER
10
(-¦
vo
S t ream
Pollutant (a) Code
Sample
Type
t
Source
Concentrations (mg/1, except
Day 1 Day 2 Day 3
as noted)
Average
Tox ic
Pollutants
4.
benzene
3
2
0.1 36
<0.013
<0.018
0.045
68
2
0.017
*
*
*
*
23.
chloroform
3
2
0.41
0.041
0.064
0.1 7
68
2
0.022
0.019
0.071
0.019
0.36
29.
1,1-dichloro-
3
2
0.099
ND
ND
0.099
ethylene
68
2
ND
ND
ND
ND
30.
1,2-1rans-dichloro-
3
2
ND
ND
*
*
ethylene
68
2
ND
0.07
0.03
0.019
0.4
44.
methylene chloride
3
2
0.37
ND
ND
0.37
68
2
ND
ND
ND
ND
•C-
00
•
dichlorobromo-
3
2
ND
ND
ND
methane
68
2
ND
ND
0.019
ND
0.019
66.
bis(2-ethylhexyl)
3
7
ND
phthalate
68
7
0.038
0.228
0.228
85.
tetrachloroethylene
3
2
0.378
ND
*
0.1 89
68
ND
to
m
o
o
55
o
>
w
~<
>
t"1
c:
2
M
z
c:
s
to
G
®
O
>
H
M
O
O
W
K
to
M
0
H
1
<
87. trichloroethylene
3
68
2
2
0.022
0.787
<0.03
ND
<0.030
<0.089
<0.031
<0.39
<0.030
-------
Table V-6 (Continued)
SECONDARY ALUMINUM SAMPLING DATA
DEMAGGING SCRUBBER LIQUOR
RAW WASTEWATER
Stream Sample
Concentrations (mg/1, except as noted)
VO
tv)
o
Pollutant
(a)
Code
Type Source
Day 1
Day 2
Day 3
Average
106.
1 07.
108.
PCB-1242
PCB-1254
PCB-1221
(b)
(b)
(b)
3
68
7
7 **
<0.020
**
<0.02
~ ~
109.
1 10.
111.
112.
PCB-1232
PCB-1248
PCB-1260
PCB-1016
(c)
(c)
(c)
(c)
3
68
7
7 **
<0.025
**
<0.025
~ ~
1 13.
toxaphene
3
68
7
7 ND
<0.011
ND
<0.011
1 1 4.
ant imony
3
68
7
7 <0.1
0.3
<0.1
0.3
<0.1
115.
arsenic
3
68
7
7 <0.01
4
<0.01
4
<0.01
1 17.
bery1lium
68
7 <0.001
0.2
0.2
1 18.
cadmi urn
68
7 0.02
0.5
0.5
1 19.
chromium
68
7 0.009
<0.05
<0.05
120.
copper
68
7 0.02
0.2
0.2
12 1.
cyan i de
3
68
7
7
<0.001
<0.001
0.003
<0.001
<0.001
0.003
c/i
m
o
O
z
o
>
w
K
>
f
c
s
M
z
c
s
c/i
c
00
n
>
H
W
O
o
w
K
C/l
m
o
H
-------
Table V-6
(Cont inued)
SECONDARY ALUMINUM SAMPLING DATA
DEMAGGING SCRUBBER LIQUOR
RAW WASTEWATER
vo
to
Pollutant
122. lead
12 3. mercury
124. nickel
125. selenium
128. zinc
Nonconvent ionals
aluminum
ammonia
chemical oxygen
demand (COD)
chloride
phenols (total by
4-AAP method)
total organic
carbon (TOC)
Stream Sample
Code Source
68
3
68
68
3
68
68
3
68
3
68
3
68
3
68
3
68
3
68
2
2
1
2
2
2
2
2
2
2
2
2
<0.02
<0.0001
<0.005
<0.01
<0.06
0.05
Concentrations (mg/1, except as noted)
Day 1 Day 2 Day 3 Average
0.0064
0.001
<0.05
0.2
<0.01
500
<0.1
0.84
48
50
6,000
3.241
0.021
3
9
ND
0.023
ND
<0.1 <0.1
0.42
0.032
0.007
0.0064
0.001
<0.05
0.2
<0.01
500
<0.1
0.63
48
50
6,000
3,241
0.02 5
0.007
3
9
w
m
o
o
52
O
>
w
~<
>
c
s
w
52
c
s
w
G
00
O
>
m
o
o
»
~<
U)
M
n
H
-------
Table V-6 (Continued)
SECONDARY ALUMINUM SAMPLING DATA
DEMAGGING SCRUBBER LIQUOR
RAW WASTEWATER
Concentrations (mg/i, except as noted)
vo
K)
M
Pollutant
S t ream
Code
Sample
Type Source
Day 1
Day 2
Day 3
Average
Convent ionals
oil and grease
3
2
121
16
1 57
98
68
2
7
7
tocal suspended
3
2
89
89
solids (TSS)
68
2
2,082
2 , U82
pH (standard units)
3
1
2.8
3.6
2.5
68
1
6
6.4
6.1
w
rc
o
o
25
o
>
50
~<
>
tr"
G
2
M
Z
G
2
{/)
G
DO
O
>
t-3
n
o
o
50
K
w
tn
o
(a) One sample from one stream was analyzed for the acid extractable toxic organic 1-3
pollutants; none was detected. •
<
(b), (c) Reported together.
-------
SECONDARY ALUMINUM SUBCATEGORY SECT -V
TABLE V-7
WATER USE AND DISCHARGE RATES FOR
DELACQUERING WET AIR POLLUTION CONTROL
(l/kkg of aluminum scrap dried)
Plant Code
Percent
Recycle
Production
Normalized
Water Use
Production
Normali zed
Discharge Rate
340
0
296
296
342
NR
NR
NR
505
98
10010
167
313
97
8170
221
4101
98
25366
610
923
-------
SECONDARY ALUMINUM SUBCATEGORY SECT -V
TABLE V-8
WATER USE AND DISCHARGE RATES FOR
SCRAP DRYING WET AIR POLLUTION CONTROL
(1/kkg of aluminum scrap dried)
Percent
Plant Code
Recycle
14
50
18
0
37
0
307
0
309
0
312
0
313
0
326
0
327
0
328
0
329
0
335
96
427
0
624
85
626
0
628
0
6202
0
Production Production
Normalized Normalized
Water Use Pischarge Rate
362
181
543
543
685
685
496
496
4347
4347
76
76
906
906
2824
2824
110
110
1139
1139
366
366
500
20
76
76
109
16
319
319
502
502
227
227
924
-------
SECONDARY ALUMINUM SUBCATEGORY SECT -V
TABLE V-9
WATER USE AND DISCHARGE RATES FOR
SCRAP DRYING WET AIR POLLUTION CONTROL
(1/kkg of aluminum scrap dried)
Production Production
Percent Normalized Normalized
Plant Code Recycle Water Use Discharge Rate
51
100
NR
0
326
0
10578
10578
634
100
NR
0
4501
NR
175
NR
925
-------
Table V-10
SECONDARY ALUMINUM SAMPLING DATA
INGOT CONVEYOR CASTING CONTACT COOLING WATER
RAW WASTEWATER
VO
NJ
>
tr1
a
s
n
Z
a
s
t/i
a
a
n
>
m
8
K
c/i
m
n
H
-------
Table V-1 1
SECONDARY ALUMINUM SAMPLING DATA
DEMAGGING WET AIR POLLUTION CONTROL AND CASTING CONTACT COOLING
COMBINED RAW WASTEWATER
\D
NJ
-J
Pollutant (a)
S t ream
Code
Sample
Type
Source
Cone
Day 1
etjt rat ions
Day 2
(ITI^/ 1 ,
Day 3
except as noted)
Average
Tox ic
Pollutants
23.
chloroform
84
2
0.01 7
0.024
*
0.01 5
0.013
73.
benzo(a)pyrene
84
3
ND
ND
0.012
0.01 2
1 17.
beryllium
84
3
0.004
0.010
0.00 7
1 18.
cadmium
84
3
0.02
0.05
0.035
120.
copper
84
3
0.070
0.070
0.070
121 .
cyan ide
84
3
0.003
0.002
0.007
0.004
122.
lead
84
3
0.06
0.07
0.065
123.
mercury
84
3
0.0002
0.0002
0.0002
128.
zinc
84
3
2.0
2.0
2.0
Nonconvent ionals
a luminum
84
3
70
90
80
chemical oxygen
demand (COD)
84
3
<5
1 1
16
14
phenols (total; by
4-AAP method)
84
2
9.0
<0.001
<0.001
3.0
m
n
o
o
55
O
>
pa
>
t-1
c
3
M
a:
c
3
m
C
O)
o
>
M
O
O
pa
K
w
w
n
I
<
-------
Table V — 11 (Continued)
SECONDARY ALUMINUM SAMPLING DATA
DEMAGGING WET AIR POLLUTION CONTROL AND CASTING CONTACT COOLING
COMBINED RAW WASTEWATER
vo
NJ
00
Pollutant
total organic
carbon (TOC)
Convent ionals
Oil and grease
total suspended
solids (TSS)
pM (standard units)
Stream Sample
Code Type
84 3
Concentrations (mg/1, except as noted)
Source Day 1 Day 2 Day 3 Average
5 6 9 7.5
84
84
84
1
3
5
60
6.8
6.6
1 3
74
6.5
8.3
67
i/i
M
rt
o
2:
o
>
~<
>
It"
c
s
M
z
c
3
(/)
c
CD
n
>
H
o
o
30
K
(a) No samples were analyzed for the acid extractable toxic organic pollutants. Two
samples were analyzed for the pesticide fraction; none was reported present above
its analytical quantification limit. PCBs were analyzed for and detected below
the quantification limit in two samples.
c/i
m
n
H
-------
Table V-12
SKCONDAKY ALUMINUM SAMPLING DATA
TREATMENT PLANT SAMPLES
PLANT A
Pollutant
Toxic Pollutants
23. chloroform
hi. bromoform
66. bis (2-ethylhexyl
phthalate)
1 1 A. ant imony
115. arsenic
121. cyan ide
Noneonvent iona Is
chemical oxygen
demand (COD)
phenols (total; by
A-AAP method)
total organic
carbon (TOC)
Concentrations (mg/1, except as noted)
Stream Sample
Code Type Source Day 1 Day 2 Day 3 Average
81
81
81
81
81
81
81
81
81
<0.1
<0.01
ND
ND
0.01 2
0.01 1
0.025
<0.001
1 .1
0.07
0.009 <0.001
1 .h
0.008 0.007 0.004
0.125
0.0055
0.01 2
1 .1
0.07
0.003
1 .4
0.006
-------
Table V-12 (Gontinued)
SECONDARY ALUMINUM SAMPLING DATA
TREATMENT PLANT SAMPLES
PLANT A
VD
U>
O
Pollutant
Convent ionals
oil and grease
total suspended
solids (TSS)
pH (standard units)
S tream
Code
81
81
81
Concentrations (mg/1, except as noted)
Sample
Type Source
Day 1
3
212
1 .4
Day 2 Day 3
28
0.9
ND
1.5
Average
1 6
212
(/)
F1
O
O
55
O
>
K
>
tr1
C
3
M
z
c
3
(/)
a,
CO
o
>
tn
o
o
»
K
(/)
tn
n
-------
Table V-1 3
SECONDARY ALUMINUM SAMPLING DATA
TREATMENT PLANT SAMPLES
PLANT B
Pollutant
S t ream
Code
Samp 1e
Type
Concent rat ions
Source Day 1
(mg/1, except as
Day 2 Day
not ed)
3 Averap.e
to
m
o
Tox ic
Pollutants
O
z
o
>
>
tr<
23.
chloroform
69
1 33
2
1
0.022
0.022
0.132
ND
0.037
0.095
30.
1,2-trans-dichlo-
roethylene
69
1 33
2
1
ND
ND
0.088
*
0.028
0.058
*
c;
2
H
z
c
48.
dichlorobromo-
methane
69
1 33
2
1
ND
ND
0.014
ND
ND
0.01 4
to
C
M
O
>
M
O
r\
6 6.
bis(2-ethylhexyl)
ph thalat e
69
133
3
1
0.038
0.038
1 .259
0.036
1 .259
0.036
6tf.
di-n-butyl phthal-
ate
69
1 33
3
1
*
*
*
0.012
*
0.012
U
»
1 15.
arsenic
69
1 33
3
1
<0.01
<0.01
<0.01
0.01
<0.01
0.01
to
M
o
. -%
117.
beryllium
69
1 33
3
1
<0.001
<0.001
0.02
0.05
0.02
0.05
*-1
1
<
1 18.
cadmi urn
69
1 33
3
1
0.02
0.02
<0.02
0.3
<0.02
0.3
119.
chromium
69
1 33
3
1
0.009
0.009
<0.05
0.09
<0.05
0.01
-------
Table V — 13 (Continued)
SECONDARY ALUMINUM SAMPLING DATA
TREATMENT PLANT SAMPLES
PLANT R
vo
UJ
NJ
1 28.
Pollutant
120. copper
121. cyanide
122. lead
123. mercury
124. nickel
zinc
Nonconventionals
aluminum
S tream
Code
69
1 33
69
1 33
69
1 33
69
133
69
1 33
69
1 33
69
1 33
Sample
TyPe
3
1
Concentrations (mg/1, except as noted)
Source
0.02
0.02
2
1
<0.02
<0.02
<0 .0001
<0.0001
<0.005
<0.005
<0.06
<0.06
0.05
0.05
Day 1
<0.06
2
0.002
<0.02
2
0.0002
0.0006
<0.05
0.2
<0.06
4
23.1
200
Day 2 Day 3 Average
<0.01
0.01
0.004
0.004
0.002
<0.02
2
0.0002
0.0006
<0.05
0.2
<0.06
4
23.1
200
w
w
o
o
2:
o
>
JO
~<
>
c
3
M
2:
c
3
w
c
tr)
o
>
w
-------
Table V- 13 (Continued)
SECONDARY ALUMINUM SAMPLING DATA
TREATMENT PLANT SAMPLES
PLANT B
u>
U)
Pollutant
chemical oxygen demand
(COD)
chloride
total organic carbon
(TOC)
phenols (total; by
4-AAP method)
Convent ionaIs
oil and grease
S t ream
Code
69
1 33
69
1 33
69
1 33
69
133
69
1 33
Sample
TVPe
2
1
2
1
2
1
2
1
Concentrations (mg/1, except as noted)
Source
Day 1
54
67
5500
3691
9
20
0.006
1 1
Day 2 Day 3 Average
54
67
0.02
5500
3691
9
20
1 3
0.02
0.006
1 3
1 1
to
w
o
O
55
O
>
~<
>
f
G
3
M
55
G
3
to
c;
w
o
>
M
O
O
»
~<
total suspended solids
(TSS)
pH (standard units)
69
133
69
2
1
240
1 1 32
5.4
240
1 132
to
M
o
-------
Table V-14
SECONDARY ALUMINUM SAMPLING DATA
TREATMENT PLANT SAMPLES
PLANT D
Concentrations (mg/L, except as noted)
S t ream
Pollutant Code
Sample
Type
Source
Day 1
Day 2
Day 3
Average
01
ra
o
Toxic
Pollutants
o
z
o
>
23.
chloroform
99
3
0.033
0.222
0.216
0.126
0.188
48.
d ichlorobromo-
methane
99
3
ND
0.0255
0.01 8
0.018
0.021
>
tr1
c
s
M
51 .
chlorodibromo-
methane
99
3
ND
<0.025
ND
0.029
0.0145
z
c
3
in
66.
bis(2-ethylhexyl)
phthalate
99
3
0.071
*
0.021
0.746
0.26
c
tr)
n
>
H
m
o
o
SO
68.
di-n-butyl phthalate
99
3
*
*
0.055
0.033
0.029
69.
di-n-ocytl phthalate
99
3
ND
*
*
0.101
0.0337
~<
1 18.
cadmium
99
3
0.004
0.008
0.3
0.04
0.1 2
c/)
ra
n
H
1 19.
chromium
99
3
0.01
0.4
0.6
0.5
0.5
1 20.
copper
99
3
<0.006
0.02
0.08
<0.06
0.033
i
<
1 21 .
cyan ide
99
3
0.003
<0.001
<0.001
0.001
1 2.2.
lead
99
3
<0.02
<0.02
0.9
0.3
0.4
1 23.
mercu ry
99
3
<0 .0001
0.004
0.0061
0.0042
0.0048
-------
Table V-14 (Continued)
SECONDARY ALUMINUM SAMPLING DATA
KD
OJ
U1
TREATMKNT PLANT
PLANT D
SAMPLES
Pollutant
S t ream
Code
Sample
Type
Concentrations (mg/1, except as noted)
Source Day 1 Day 2 Day 3 Average
124. nickel
99
3
<0.005
0.03 0.08 0.4
0.17
127. thallium
99
3
<0.1
•
o
•
o
•
o
0.033
128. zinc
99
3
<0.06
0.1 <0.6 <0.6
0.033
Nonconvent ionals
aluminum
99
3
<0.05
2 3 1
2
chemical oxygen demand
(COD)
99
3
10 6 <5
5
chloride
99
3
2510 2270 2170
231 7
phenols (total; by
4-AAP method)
99
1
0.022 <0.001 <0.001
O
O
•
O
total organic carbon
(TOC)
99
3
6 6 6
6
Conventlonals
oil and grease
99
1
4 8 5
6
total suspended solids
99
3
9 9 13
10
U)
rc
o
o
z
o
>
K
>
t"1
C
s
w
c
w
o
>
H
rc
o
o
»
K
t/i
M
0
t-3
1
<
(TSS )
-------
Table V-15
SECONDARY ALUMINUM SAMPLING DATA
TREATMENT PLANT SAMPLES
PLANT E
u>
cn
Pollutant:
Toxic Pollutants
4. benzene
10. 1,2-dichloroethane
11. 1 ,1 ,1 -1 ri chloro-
ethane
15.
1,1,2,2-1 et rachlo-
roethane
23. chloroform
29. 1,1-dichloro-
ethylene
44. methylene chloride
51. chlorodibromometh-
ane
85. tetrachloroethylene
87. trichloroethylene
114. ant imony
S t ream
Code
4
4
4
4
4
4
4
4
4
4
Sample
'1'ype
2
2
2
Concentrations (mg/1, except as noted)
Source Day 1 Day 2 Day 3 Average
2
2
2
2
2
2
2
0.018
0.047
ND
ND
0.386
0.109
0.473
ND
0.025
0.098
0.06
<0.018
ND
ND
ND
0.056
ND
ND
0.012
ND
<0.098
<0.014
0.124
0.016
<0.011
0.085
ND
ND
ND
<0.011
<0.074
0.06
0.086
0.01 6
<0.011
0.18
0.109
0.473
0.012
0.01 2
0.033
0.06
in
m
n
o
•z
o
>
JO
~<
>
f
c
s
i—i
2:
c
s
w
c
w
n
>
H
M
O
O
JO
K
W
n
-------
Table V-15 (Continued)
SECONDARY ALUMINUM SAMPLING DATA
TREATMENT PLANT SAMPLES
PLANT E
vo
u>
S t ream
Code
4
4
4
Pol Intrant
121. cyanide
123. mercury
125. selenium
Nonconventionals
ammonia 4
chemical oxygen demand 4
(COD)
chloride 4
phenols (total; by 4
4-AAP method)
total organic carbon (TOC) 4
Convent ionaIs
oil and grease 4
total suspended solids 4
(TSS)
Sample
Type
2
2
2
2
2
2
2
2'
1
2
Concentrations (mg/1, except as noted)
Source Day 1 Day 2 Day 3 Average
<0.001 <0.001 0.001 0.0003
0.0035 0.0035
0.02 0.02
<0.1
40
4140
0.01 2
122
7
1950
>0.1
0.005
<0.1
<0.1
40
4140
0.017 0.011
122
8 7
1950
to
m
n
o
55
O
>
K
>
G
3
M
G
3
to
G
DO
n
>
•-a
M
o
o
»
K
to
m
n
pH (standard units)
7.0
7.8
6.8
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - V
SOURCE
WATER
DE2'ACGItlc; I
SCK'w'BBER
water
0 73 VOA SLAtfK
SETTLING
!' 081
J"
0.005
MGD
DISCIIARC.F.
CASTING
CONTACT &
SCNC0N7ACT
COOLING
WATER
0.C05 MGB
Figure V-l
SAMPLING SITES AT SECONDARY ALUMINUM PLANT A
938
-------
SECONDARY ALUMINUM SUBCATEGORY SECT
- V
SOURCE
BAY
WATER
i 066 i VOA BLANK
foeTl
i 1 .
1
t
a
DROSS
KILLING
o
o
070
&
•v .
i
FIRST j
LAGOON l
7 KGD
DEV-ACGING
SCRU3BER
water
063
&
SECOND
LAGOON
THIRD
LAGOON
;.oi40 yc:
RECYCLE TO BALL MILL
133
D1 SOURCE
Figure V-2
SAMPLING SITES AT SECONDARY ALUMINUM PLANT B
939
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - V
SOURCE
WATER
VOA 3LANK
083
SHCT
CASTING
CKLISC
WATER
SCRUBBER
WATER
Figure V-3
SAMPLING SITES AT SECONDARY ALUMINUM PLANT C
940
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - V
098
(NaOK AEDES DURING RSCTCU3G
0.0052 >CD
SOlTtCE
WATER
SECONDARY
SETTLING
DISCHARTE
Figure V-4
SAMPLING SITES AT SECONDARY ALUMINUM PLANT D
941
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - V
SOURCE WATER
0.036 MGD
0C3
004
036 mc;
Figure V-5
SAMPLING SITES AT SECONDARY ALUMINUM PLANT E
942
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - VI
SECTION VI
SELECTION OF POLLUTANTS
This section examines the chemical analysis data presented in
section V and discusses the selection or exclusion of pollutants
for potential limitation. The basis for the regulation of toxic
and other pollutants is presented in Section VI of volume I of
this document. Additionally, each pollutant selected for
potential limitation is discussed there. That discussion provides
information about where the pollutant originates (i.e., whether
it is a naturally occurring substance, processed metal, or a
manufactured compound); general physical properties and the form
of the pollutant; toxic effects of the pollutant in humans and
other animals; and behavior of the pollutant in POTW at the
concentrations expected in industrial discharges. The discussion
that follows describes the analysis that was performed to select
or exclude pollutants for further consideration in the
limitation for this subcategory.
The discussion that follows describes the analysis that was
performed to select or exclude pollutants for further
consideration for limitations and standards. Pollutants will be
further considered if they are present in concentrations
treatable by the technologies considered in this analysis. The
treatable concentration used for the toxic metals were the long-
term average performance values achievable by lime precipitation,
sedimentation, and filtration. The treatable concentrations used
for the toxic organics were the long-term performance values
achievable by carbon adsorption.
After proposal, the Agency re-evaluated the treatment performance
of activated carbon adsorption to control toxic organic
pollutants. The treatment performance for the acid extractable,
base-neutral extractable, and volatile organic pollutants has
been set equal to the analytical quantification limit of 0.010
mg/1. The analytical quantification limit for pesticides and
total phenols (by 4-AAP method) is 0.005 mg/1, which is below the
0.010 mg/1 accepted for the other toxic organics. However, to be
consistent, the treatment performance of 0.010 mg/1 is used for
pesticides and total phenols. The 0.010 mg/1 concentration is
achievable, assuming enough carbon is used in the column and a
suitable contact time is allowed. The frequency of occurrence
for 36 of the toxic pollutants has been redetermined based on the
revised treatment performance value. No toxic organic pollutants
have been selected Cor further consideration for limitation as a
result of the revised treatment performance. However, sampling
data for delacquering wet air pollution control submitted to the
Agency through data collection requests have demonstrated the
presence of 4-AAP phenols and phenol (pollutant number 65). As
discussed below, these pollutants, which were not considered for
limitation at proposal, have been selected for consideration for
limitation.
943
-------
SECONDARY ALUMINUM SUBCATEGORY
SECT - VI
CONVENTIONAL AND NONCONVENTIONAL POLLUTANT PARAMETERS
This study examined samples
gory for three conventional
total suspended solids, and
tant parameters (ammonia,
from the secondary aluminum subcate-
pollutant parameters (oil and grease,
pH) and seven nonconventional pollu-
chemical oxygen demand, chloride,
fluoride, aluminum, total organic carbon, and total phenols)
CONVENTIONAL AND NONCONVENTIONAL POLLUTANT PARAMETERS SELECTED
The conventional and nonconventional pollutants or pollutant
parameters selected for consideration for limitation in this
subcategory ares
aluminum
ammonia
total phenols (4-AAP)
total suspended solids (TSS)
oil and grease
pH
Aluminum was found above the 1.49 mg/1 concentration attainable
by identified treatment technology in four of six samples in
three plants. Because it is the major product of plants in this
subcategory and was found at treatable concentrations, aluminum
is selected for consideration for limitation.
Ammonia was measured at three sites at two plants. The
concentration of ammonia in these samples varied widely,
depending on the stage and type of manufacturing process. Those
plants that produce treatable concentrations of ammonia will be
considered for limitation for that pollutant.
Total suspended solids ranged from 60 to 20,140 mg/1 in six
samples. All of the measured concentrations are well above the
concentration achievable by identified treatment technology.
Furthermore, most of the technologies used to remove toxic metals
do so by converting these metals to precipitates, and these
toxic-metal-containing precipitates should not be discharged.
Meeting a limitation on total suspended solids also ensures that
sedimentation to remove precipitated toxic metals has been
effective. For these reasons, total suspended solids is
considered for limitation in this subcategory.
Data solicited by the Agency through data collection requests
have demonstrated the presence of 4-AAP phenols in delacquering
scrubber liquor. Five sample analyses were submitted to EPA with
phenolics concentrations ranging from 0.346 mg/1 to 26.8 mg/1.
Three concentrations were greater than 3 ma/l. The toxic
pollutant phenol (number 65) was found at 5.4 mg/1 in one sample.
Based on this concentration and its frequency in delacquering wet
air pollution control wastewater, total phenols (4-AAP) is
selected for consideration for limitation.
944
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - VI
Oil and grease was found above its treatable concentration (10
mg/1) in six of seven samples with concentrations ranging from 16
to 157 mg/1. Sampling data from direct chill casting raw
wastewater taken at aluminum forming plants show oil and grease
present at treatable concentrations in 15 of 23 samples. The
treatable concentrations range from 15 to 226 mg/1. Therefore,
oil and grease is selected for consideration for limitation.
The pH of a wastewater measures its relative acidity or
alkalinity. In this study, the pH values observed in raw
wastewater ranged from 2.8 to 9.6. Effective removal of toxic
metals by precipitation requires careful control at pH.
Therefore, pH is considered for limitation in this subcategory.
TOXIC POLLUTANTS
The frequency of occurrence of the toxic pollutants in the
wastewater samples taken is presented in Table VI-1 (page 953).
These data provide the basis for the categorization of specific
pollutants, as discussed below. Table VI-1 is based on the raw
wastewater data from streams 3, 68, 70, 80, and 84 (see Section
V). Treatment plant sampling data were not considered in the
frequency count.
TOXIC POLLUTANTS NEVER DETECTED
The toxic pollutants listed in Table VI-2 (page 957) were not
detected in any wastewater samples from this subcategory;
therefore, they were not selected for consideration in
establishing limitations.
TOXIC POLLUTANTS NEVER FOUND ABOVE THEIR ANALYTICAL
QUANTIFICATION LIMIT
The toxic pollutants listed below were never found above their
analytical quantification level in any wastewater samples from
this subcategory; therefore, they were not selected for
consideration in establishing limitations.
91.
chlordane
92.
4,4'-DDT
93.
4,4'-DDE
98.
endrin
99.
endrin aldehyde
100 .
heptachlor
101 .
heptachlor
epoxide
102 .
alpha-BHC
103 .
beta-BHC
104 .
gamma-BHC
106 .
PCB-124 2
(a)
107 .
PBC-1254
(a)
108.
PC3-1221
(a)
109 .
PC3-1232
( b)
110 .
PC3-1248
(b)
Ill .
PC3-1260
(b)
945
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - VI
112. PCB-1016 (b)
113. toxaphene
121. cyanide
(a),(b) Reported together.
TOXIC POLLUTANTS PRESENT BELOW CONCENTRATIONS ACHIEVABLE BY
TREATMENT
The pollutants listed below were not selected for consideration
in establishing limitations because they were not found in any
wastewater samples from this subcategory above concentrations
considered achievable by existing or available treatment
technologies. These pollutants are discussed individually
following the list.
114. antimony
117. beryllium
123. mercury
125. selenium
126. silver
Antimony was found above its analytical quantification limit in
one of six samples collected at four plants. The concentration
found was 0.3 mg/1, which was below that achievable by
identified technology. Therefore, antimony was not considered
for limitation.
Beryllium was found above its analytical quantification limit in
three of four samples. The maximum concentration measured was
0.20 mg/1. The concentration achievable by identified treatment
technology are 0.20 mg/1. Therefore, beryllium was not
considered for limitation.
Mercury was detected above its analytical quantification limit in
all five samples of this subcategory, ranging from 0.0002 to
0.0064 mg/1. All of the values were below the 0.036 mg/1
concentration achievable by identified treatment technology.
Therefore, mercury was not considered for limitation.
Selenium was found above its quantification concentration in one
of three samples collected at three plants. The concentration
found was 0.20 mg/1, which was the concentration achievable by
identified treatment technology. Therefore, selenium was not
considered for limitation.
Silver was found above its analytical quantification limit in one
of three samples with a value of 0.07 mg/1. This concentration
was equal to that achievable by identified treatment technology.
Therefore, silver are not considered for limitation.
TOXIC POLLUTANTS DETECTED IN A SMALL NUMBER OF SOURCES
The following pollutants were not selected for consideration for
limitation on the basis they were detectable in the effluent from
946
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - VI
only a small number of sources within the subcategory and it is
uniquely related to only those sources.
4.
benzene
23.
chloroform
27.
1,4-dichlorobenzene
29.
1,1-dichloroethylene
30.
1,2-trans-dichloroethylene
39.
fluoranthene
44.
methylene chloride
48.
dichlorobromomethane
66.
bis(2-ethylhexyl) phthalate
67.
butyl benzyl phthalate
68.
di-n-butyl phthalate
69.
di-n-octyl phthalate
71.
dimethyl phthalate
73.
benzo(a)pyrene
76.
chrysene
77.
acenaphthylene
84.
•pyrene
85.
tetrachloroethylene
87.
trichloroethylene
115.
arsenic
119.
chromium
120.
copper
124.
nickel
127.
thallium
Although these pollutants were not selected for consideration in
establishing nationwide limitations, it may be appropriate, on a
case-by-case basis, for the permit writer to specify effluent
limitations.
Benzene was found above its analytical quantification limit in
one of 12 samples collected at four plants. The concentration of
0.136 mg/1 was above the concentration achievable by identified
treatment technology. Also, all secondary aluminum plants
indicated in the dcp that this pollutant was known to be absent
or believed to be absent from their wastewater. Because it was
found above a treatable concentration at only one plant, benzene
was not considered for limitation.
Chloroform, a common laboratory solvent, was found above its
analytical quantification limit in 10 of 12 samples collected at
four plants. The 10 samples ranged from values of 0.019 to 0.410
mg/1 which were at concentrations above that achievable by
treatment. All secondary aluminum plants indicated in the dcp
that this pollutant was known to be absent or believed to be
absent from their wastewater. Because the possibility of sample
contamination is likely, chloroform was not considered for
limitation.
1,4-Dichlorobenzene was found above its analytical quantification
concentration in only one of six samples collected from three
plants with a concentration of 0.026 mg/1, which was treatable by
947
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - VI
identified technology. However, all secondary aluminum plants
indicated in the dcp that this pollutant was known to be absent
or believed to be absent from their wastewater. Since it was
detected in only one plant, 1,4-dichlorobenzene was not
considered for limitation.
1.1-Dichloroethylene was detected in only one of 12 samples
collected at four plants. Its concentration was 0.099 mg/1,
which was above the concentration achievable by available
treatment (0.010 mg/1). Because it was found at only one plant,
indicating the pollutant is site-specific, 1/1-dichloroethylene
was not considered for limitation.
1.2-trans-Dichloroethylene was found above its treatable
concentration (0.010 mg/1) in five of 12 samples. All five
samples were taken at the same plant, including three from
demagging scrubber wastewater. However, this pollutant was not
detected in six samples from three other plants. Five of these
six samples were taken from demagging scrubber wastewater or
combined wastewater including demagging scrubber wastewater.
Also, all secondary aluminum plants reporting in the dcp
indicated that this pollutant was believed to be absent from
their wastewater. Since this pollutant was found in treatable
concentrations at only one plant, indicating it is site-specific,
1,2-trans-dichloroethylene was not considered for limitation.
Fluoranthene was detected above its analytical quantification
limit in only one of six samples collected at three plants. The
reported fluoranthene concentration, 0.020 mg/1, was above the
concentration achievable by available treatment. However, all
secondary aluminum plants indicated in the dcp that this
pollutant was known to be absent or believed to be absent from
their wastewater. Because it was found at only one plant,
indicating the pollutant is site-specific, fluoranthene was not
considered for limitation.
Methylene chloride was found above its analytical quantification
limit in one of 12 samples. The measurable concentration was
0.370 mg/1. This pollutant was not attributable to specific
materials or processes associated with the secondary aluminum
subcategory; however, it is a common solvent used in analytical
laboratories. Also, all secondary aluminum plants indicated in
the dcp that this pollutant was known to be absent or believed to
be absent from their wastewater. Since the possibility of sample
contamination was likely, methylene chloride is not considered
for limitation.
Dichlorobromomethane was detected in only one of 12 samples
collected at four plants. Its concentration was 0.019 mg/1,
which was above the" concentration achievable by available
treatment (0.010 mg/1). Because it was found at only one plant,
indicating the pollutant was site-specific, dichlorobromomethane
was not considered for limitation.
Bis(2-ethylhexyl) phthalate was found above its analytical
948
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - VI
quantification limit in three of six samples. The concentrations
measured were 0.075, 0.28, and 2.03 mg/1. The presence of this
pollutant was not attributable to materials or processes
associated with the secondary aluminum subcategory. It is
commonly used as a plasticizer in laboratory and field sampling
equipment. EPA suspects sample contamination as the source of
this pollutant. Also, all secondary aluminum plants indicated
in the dcp that this pollutant was known to be absent or believed
to be absent from their wastewater. Therefore, bis(2-ethylhexyl)
phthalate was not considered for limitation.
Butyl benzyl phthalate was found above its analytical
quantification limit in two of six samples collected from three
plants. The measured values were 0.014 and 0.098 mg/1. The
presence of this pollutant was not attributable to materials or
processes associated with the secondary aluminum subcategory. It
is commonly used as a plasticizer in laboratory and field
sampling equipment. EPA suspects sample contamination as the
source of this pollutant. Also, all secondary aluminum plants
indicated in the dcp that this pollutant was known to be absent
or believed to be absent from their wastewater. For these
reasons, butyl benzyl phthalate was not considered for
limitation.
Di-n-butyl phthalate was found above its analytical
quantification limit in two of six samples, with concentrations
of 0.022 and 0.045 mg/1. The presence of this pollutant was not
attributable to materials or processes associated with the
secondary aluminum subcategory. It is commonly used as a
plasticizer in laboratory and field sampling equipment. EPA
suspects sample contamination as the source of this pollutant.
Also, all secondary aluminum plants indicated in the dcp that
this pollutant was known to be absent or believed to be absent
from their wastewater. Therefore, di-n-butyl phthalate was not
considered for limitation.
Di-n-octyl phthalate was found above its analytical
quantification limit in only one of six samples collected at
three plants, at a concentration of 0.036 mg/1. The presence of
this pollutant was not attributable to materials or processes
associated with the secondary aluminum subcategory. It is
commonly used as a plasticizer in laboratory and field sampling
equipment. EPA suspects sample contamination as the source of
this pollutant. Also, all secondary aluminum plants indicated in
the dcp that this pollutant was known to be absent or believed to
be absent from their wastewater. For these reasons, di-n-octyl
phthalate was not considered for limitation.
Dimethyl phthalate was detected at a concentration greater than
its analytical quantification limit in only one of six samples
collected at three plants. The measured concentration of this
toxic pollutant was 0.056 mg/1. Also, all secondary aluminum
plants indicated in the dcp that this pollutant was known to be
absent or believed to be absent from their wastewater. Because
it was found at just one plant, dimethyl phthalate was not
949
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - VI
considered for limitation.
Benzo(a)pyrene was detected at a concentration above its
analytical quantification limit in only one of six samples
collected at three plants. The 0.012 mg/1 concentration measured
was above the concentration achievable by identified treatment
technology. However, all secondary aluminum plants indicated in
the dcp that this pollutant was known to be absent or believed to
be absent from their wastewater. Because it was found at only
one plant, benzo(a)pyrene was not considered for limitation.
Chrysene was detected at a concentration above its analytical
quantification limit in only one of six samples collected at
three plants. The 0.017 mg/1 concentration measured was above
the concentration achievable by identified treatment technology.
However, all secondary aluminum plants indicated in the dcp that
this pollutant was known to be absent or believed to be absent
from their wastewater. Because it was found only at one plant,
chrysene was not considered for limitation.
Acenaphthylene was detected at a concentration above its
analytical quantification limit in only one of six samples
collected at three plants. The 0.017 mg/1 concentration measured
was above the concentration achievable by identified treatment
technology. Also, all secondary aluminum plants indicated in the
dcp that this pollutant was known to be absent or believed to be
absent from their wastewater. Because it was found at only one
plant, acenaphthylene was not considered for limitation.
Pyrene was measured at a concentration greater than its
analytical quantification limit in only one of six samples
collected at three plants. The concentration of this toxic
pollutant was 0.024 mg/1. Also, all secondary aluminum plants
indicated in the dcp that this pollutant was known to be absent
or believed to be absent from their wastewater. Because it was
found at just one plant, pyrene was not considered for
limitation.
Tetrachloroethylene was found above its analytical quantification
limit and above the concentration attainable by available
treatment in only one of 12 samples collected from four plants,
indicating the pollutant was site-specific. The measured
concentration was 0.378 mg/1. Also, all secondary aluminum
plants indicated in the dcp that this pollutant was known to be
absent or believed to be absent from their wastewater.
Therefore, tetrachloroethylene was not considered for limitation.
Trichloroethylene was found above its analytical quantification
limit and treatable concentration in one of 12 samples collected
from four plants. The sample concentration was 0.787 mg/1. Also,
all secondary aluminum plants indicated in the dcp that this
pollutant was known to be absent or believed to be absent from
their wastewater. Since this pollutant was found at only one
plant, trichloroethylene was not considered for limitation.
950
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - VI
Arsenic was found above its treatable concentration in one of
three samples collected at four plants. The concentration of
arsenic was 4.0 mg/1. Since it was found at a treatable
concentration only one plant, arsenic was not considered for
limitation.
Chromium was found above its treatable concentration in one of
three samples collected at two plants. This sample contained 2.0
mg/1 of chromium. Since a treatable concentration of chromium
was collected at only one plant, chromium was not considered for
limi tat ion.
Copper was found above its treatable concentration in one of four
samples, with a value of 10.0 mg/1. Since copper was found at
only one plant, it was considered specific to that site and was
not considered for limitation.
Nickel was detected above its treatable concentration in one of
three samples (1.0 mg/1). Since it was found in only one plant,
nickel was not considered for limitation.
Thallium was detected above its treatable concentration in one of
three samples collected at three plants. Because it was found at
only one plant, thallium was not considered for limitation.
TOXIC POLLUTANTS SELECTED FOR CONSIDERATION FOR ESTABLISHING
LIMITATIONS
The pollutants listed below were selected for further
consideration in establishing limitations and standards for this
subcategory. The toxic pollutants selected are each discussed
following the list.
65. phenol
118. cadmium
122. lead
128. zinc
Phenol was detected in one of three samples above treatable
concentrations. Delacquering wet air pollution control
wastewater, based on data from one sample submitted to the
Agency, contains phenol. Also, the data show that delacquering
wet air pollution control wastewater contains total phenolics in
concentrations up to 26.8 mg/1. In five analyses submitted to
the Agency, total phenolics was above treatable concentrations in
all five samples. Therefore, phenol was selected for
consideration for limitation.
Cadmium was detected above its analytical quantification limit in
four samples collected at two plants. The values ranged from
0.020 to 0.500 mg/1. Three of the concentrations were above the
concentration of 0.049 mg/1, which is achievable by the
identified treatment technology. Data supplied to EPA by an
industry representative showed cadmium at 0.64 mg/1 in one sample
from delacquering wet air pollution control. Therefore, cadmium
951
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - VI
was selected for consideration for limitation.
Lead was detected present above its analytical quantification
limit in all four samples collected at two plants. The reported
lead concentrations ranged from 0.060 to 8.0 mg/1. A lead
concentration of 0.08 mg/1 is achievable by identified treatment
technology. Data supplied to EPA by industry representatives
showed lead above treatable concentrations in two of five samples
(0.1 and 2.1 mg/1) for delacquering wet air pollution control.
Therefore, lead was selected for consideration for limitation.
Zinc was detected above its analytical quantification limit in
all four samples collected at two plants. The concentrations of
zinc reported ranged from 2.0 to 8.0 mg/1. The concentration of
zinc achievable by identified treatment technology is 0.23 mg/1.
Data supplied to EPA by industry representatives showed zinc
above treatable concentrations in three of five samples (0.824,
0.898, and 7.3 mg/1) for delacquering wet air pollution control.
Therefore, zinc was selected for consideration for limitation.
952
-------
Table VI-1
FREQUENCY OF OCCURRENCE OF TOXIC POLLUTANTS
SECONDARY ALUMINUM
RAW WASTEWATER
vo
LP
UJ
Analyt tea!
Treatable
Quant IfIcatIon
Concentra-
Nuntoer of
Nunfcer of
Concentration
tion
Si reams
SOTple-s
Pollutant
(ma/l)(a)
(n«/l)(b)
Analyzed
Analyzed
ND
1. acenaphthene
0.010
0.010
5
6
6
2. acrolein
0.010
0.010
5
12
12
3. acrylonltrlle
0.010
0.010
5
12
12
U. benzene
0.010
0.010
5
12
6
3. benzidine
0.010
0.010
5
6
6
6. carbun tetrachloride
0.010
0.010
5
12
12
7. chlorohen7.CT>e
0.010
0.010
5
12
12
8. 1,2.4-trlchlorobenzene
0.010
0.010
5
6
6
9. hexachlorobrnzfTK*
0.010
0.010
6
6
10. 1,2-dlchloroethane
0.010
0.010
5
12
12
11. 1,1,1-trlchloroethane
0.010
0.010
5
12
12
12. hcnadilororlhnne
0.010
0.010
5
6
6
13. 1,1 -dlchloroelh.me
0.010
0.010
5
12
12
14. 1 ,1,2-trlcb1ororth«nr
0.010
0.010
5
12
12
13. 1.1,2,2-tetrachloroethane
0.010
0.010
5
12
12
16. cbloroethane
0.010
0.010
5
12
12
17. b!s(cbloro»rr»thyl) ether
0.010
0.010
5
12
12
18. bls(2-chloroethyl) ether
0.010
0.010
5
6
6
19. 2-chloroethyl vinyl ether
0.010
0.010
5
12
12
20. 2-chloronnphthalene
21. 2,4,6-trlchlorophenol
0.010
0.010
5
6
6
0.010
0.010
2
2
2
22. paradilorometa cresol
0.010
0.010
2
2
2
23. chloroform
0.010
0.010
5
12
2U. 2-chlorophCT»l
0.010
0.010
2
2
2
25. 1,2-dtchlorobenz«>e
0.010
0.010
5
6
6
26. 1,3-dlchlorobenzene
0.010
0.010
5
6
6
27. 1,4-dlchloroberweno
0.010
0.010
5
6
5
28. 3,3'-dlchlorobenzldlne
0.010
0.010
5
6
6
29. 1,1 -dlchloroeLhy Ime
0.010
0.010
5
12
11
30. 1,2-trans-dlrhloroethylene
0.010
0.010
5
12
6
31. 2.6-dlchlorophcnol
0.010
0.010
2
2
2
32. 1,2-dlchloropropane
0.010
0.010
5
12
12
33. 1.3-dlchloroprcpyle>e
0.010
0.010
5
12
12
34. 2,4-dlroethy 1 phenol
0.010
0.010
2
2
2
33. 2,4-dlnltrotoluFne
0.010
0.010
5
6
6
36. 2,6-dlnltrotoluene
0.010
0.010
5
6
6
'37. 1,2-dlphenylhydrazlne
0.010
0.010
5
6
6
Detected Below
Quant IfIcatIon
Concentration
Dp tected
Below Treat-
able Concen-
tration
Detected
Above Treat-
able Concen-
tration
II
in
m
O
o
55
O
£
K
>
C/l
c
W
O
>
1-3
M
O
O
W
K
Cn
W
O
H3
-------
Table VI-1 (Continued)
FREQUENCY OF OCCURRENCE OF TOXIC POLLUTANTS
SECONDARY ALUMINUM
RAW WASTEWATER
U1
•fe.
Analytical
Treatable
l>etected Detected
Quantification
Concentra-
Number of
Number of
Detected Below
Below Treat- Above Treat-
Concentration
tion
Stream
Samples
Quint If leaf Ion
able Concen- able Concen-
Pollutant
(nR/l)(a)
(n*/l)(b)
Analyzed
5
Analyzed
NO
Concentration
tration trat Ion
38. ethylbenzene
0.010
0.010
12
12
39. fhioranthene
0.010
0.010
5
6
5
1
AO. 4-chlorophenyl phenyl ether
0.010
0.010
5
6
6
41. 4-bromnphenyl phenyl ether
0.010
0.010
3
6
6
42. bi9(2-chlorolsopropyl) ether
0.010
0.010
5
6
6
43. bls(2-chloroethoJcy) meth«ne
0.010
0.010
b
6
6
44. methylene chloride
0.010
0.010
b
12
II
1
45. methyl dilorlde
0.010
0.010
b
12
12
46. methyl bromide
0.0)0
0.010
b
12
12
47. bromoforro
0.010
0.010
b
12
12
48. dlchlorobroraometh»ie
0.010
0.010
b
12
11
1
49. trlchlorofluororoethflne
0.010
0.010
b
12
12
50. dlchlorodl fluoromethme
0.010
0.010
b
12
12
51. ch lorod I bromomethane
0.010
0.010
b
12
12
52. hcxachlorobutadlene
0.010
0.010
b
6
6
53. hexachlorocyclnpentadlene
0.010
0.010
5
6
6
54. 1aophorone
0.010
0.010
b
6
6
55. naphthalan**
0.010
0.010
b
6
6
56. nltrohenzme
0.010
0.010
b
6
6
57. 2-nltrophenol
0.010
0.010
2
2
2
58. 4-nltrophenol
0.010
0.010
2
2
2
59. 2,4-dlnltrophenol
0.010
0.010
2
2
2
60. 4.6-dlnltro-o-creeol
0.010
0.010
2
2
2
61. N-nltrosodlmethylanlne
0.010
0.010
b
6
6
62. N-nltrosodlphenylaralne
0.010
0.010
b
6
6
63. N-nItrosodI-n-propylamine
0.010
0.010
b
6
6
64. pent achlorophaiol
0.010
0.010
2
2
2
65. phc^wl
0.010
0.010
2
2
2
66. bl9(2-ethylhexyl) phthalate
0.010
0.010
b
6
3
)
67. butyl benzyl phthalate
0.010
0.010
b
6
4
2
68. dl-n-butyl phthaLite
0.010
0.010
b
6
l>
2
69. dl-n-octyl phthalate
0.010
0.010
b
6
b
1
70. diethyl phthaLate
0.010
0.010
b
6
6
71. dimethyl phthalate
0.010
0.010
b
6
b
1
72. hcnzo(a)anthracaie
0.010
0.010
b
6
6
73. ben7.o(a)pyr**w»
0.010
0.010
b
6
b
1
74. 3,4-ben7.otluoranth<*ie
0.010
0.010
b
6
6
(/)
w
n
o
55
D
>
K
>
r>
a
s
M
25
a
2
c/i
c
m
n
>
w
o
o
50
K
w
M
n
t-3
-------
Table VI-1 (Continued)
FREQUENCY OF OCCURRENCE OF TOXIC POLLUTANTS
SECONDARY ALUMINUM
RAW WASTEWATER
VO
U1
en
Analytical
Treatable
Delectwl Detected
Quant If leal Inn
Concentra-
Nuifcer of
Number of
Detected Below
BelcwTreat- Abovt' Treat
Concent rat tern
l Ion
Streams
Samples
C^iantlflcatlon
able Concen- able Concen
Pollutant
(m*/l)(a)
to/pty
Analyzed
Analyzed
NO
Concentration
(ration trntlon
75. benzoOOfluoranthene
0.010
0.010
5
6
6
76. chrysoie
0.010
0.010
5
6
5
1
77. acenaphthylene
0.010
0.010
5
6
5
1
78. anthracene (c)
0.010
0.010
5
6
6
79. benzo(ghl)perylene
0.010
0.010
5
6
6
80. fluorene
0.010
0.010
5
6
6
81. phenanthrene (c)
0.010
0.010
5
6
6
82. dlbenzo(a,h)anthr»cene
0.010
0.010
5
6
6
83. IndenoO ,2, 3-cd)pyrene
0.010
0.010
5
6
6
84. pyrene
0.010
0.010
5
6
5
1
85. tetrachloroethylene
0.010
0.010
5
12
7
4
1
86. toluene
0.010
0.010
5
12
12
87. trlchloroethylene
0.010
0.010
5
12
5
6
1
88. vinyl chloride
0.010
0.010
5
12
12
89. aldrln
0.005
0.010
5
6
6
•
90. dleldrln
0.005
0.010
5
6
6
91. chlordane
0.005
0.010
5
6
2
4
92. 4,4"-DOT
0.005
0.010
5
6
2
4
93. 4.4'-DOC
0.005
0.010
5
6
3
3
94. 4,4,-W»
0.005
0.010
5
6
6
95. alpha-endo9ulfm
0.005
0.010
5
6
6
96. beta-endasulfan
0.005
0.010
6
6
97. endoaulftai sulfate
0.005
0.010
5
6
6
98. endrln
0.005
0.010
5
6
5
1
99. enrfrln aldehyde
0.005
0.010
5
6
4
2
100. heptachlor
0.005
0.010
5
6
2
4
101. heptachlor epoxide
0.005
0.010
5
6
4
2
102. alpha-BHC
0.005
0.010
5
6
4
2
103. beta-BIIC
0.005
0.010
5
6
2
4
104. gonna-BHC
0.005
0.010
5
6
3
3
105. delta-BHC
0.005
0.010
5
6
6
106. PCB-1242 (d)
0.005
0.010
5
6
1
5
107. PCB-1254 (d)
0.005
108. PCB-I22I (d)
0.005
109. PCB-1232 (e)
0.005
0.010
5
6
1
5
110. PUB-I248 (e)
0.005
111. PCB-1260 (e)
0.005
112. PCB-I0I6 (e)
0.005
Ui
M
n
o
2:
o
>
>
r
c
s
Ui
c
Cd
n
>
t-3
M
Q
O
»
Ui
w
n
t-3
-------
Table VI-1 (Continued)
FREQUENCY OF OCCURRENCE OF TOXIC POLLUTANTS
SECONDARY ALUMINUM
RAW WASTEWATER
Pollutant
Analytical
Qamt I f lent Ion
Gottceril rat ton
(hr/ i) (a)
Treatable
Concent ra-
t ion
(iHR/l)(b)
Number of
St rc.mB
Analyzed
thmfyer of
Sanples
Analyzed
ND
Detected Below
(Jjantl float Ion
Concentration
Detected
Below Trent -
able Concen-
tratIon
Detected
Abwe Treat-
able Concen-
tration
vO
tn
ON
113. toxaphwie
0.005
0.010
5
6
5
1
Hi. antimmy
0.100
0.47
3
3
2
I
115. arsenic
0,010
0.14
3
3
1
1
1
116. asbestos
10 MFl.
10 m.
1
1
1
117. beryllium
0.010
0.20
3
4
I
3
118. catAnlus
0.002
0.049
3
4
1
3
U9. chromium
0,005
0.07
3
4
3
1
120. copi»er
0.009
0.39
3
4
3
1
121. cyanide (f)
0.02
0.04?
5
10
9
1
122. lead
0.020
0.08
3
4
2
2
123. mercury
0.0001
0.016
4
5
5
124. nickel
0.005
0.22
3
3
2
1
125. selenium
0.01
0.20
3
3
2
1
126. si Ivor
0.02
0.07
3
3
2
1
127. thallium
0.100
0.34
3
3
2
1
128. zinc
0.050
0.23
3
4
4
129. 2,3.7,8-tetrachlorodlbenzo-
Not Analyzed
p-dloxln (TOO)
(a) Analytical quantification concentration was reported with the data (see Section V).
(b) Treatable concentrations are based an performance of lime precipitation, sedimentation, and flit ratli*i for toxic metal pollutanr r aid activated
carbon adsorption for toxic organic pollutants.
(c),(d),(e) Reported together.
(f) Analytical quantification concentration for EPA Method 335.2, Total Cyanide Methods for ChHnlcal Analysis of Uater and Wastes, EPA-600/4-79-020,
March 1979.
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - VI
TABLE VI-2
TOXIC POLLUTANTS NEVER DETECTED
1.
acenaphthene
2.
acrolein
3.
acrylonitrile
5.
benzidine
6.
carbon tetrachloride
7.
chlorobenzene
8.
1,2,4-tr ichlorobenzene
9.
hexachlorobenzene
10.
1,2-dichloroethane
11.
1,1,1-trichloroethane
12.
hexachloroethane
13.
1,1-dichloroethane
14.
1,1,2-tr ichloroethane
15.
1,1,2,2-tetrachloroethane
16.
chloroethane
17.
DELETED
18.
bis(2-chloroethyl) ether
19 .
2-chloroethyl vinyl ether
20.
2-chloronaphthalene
21.
2,4,6-trichlorophenol
22.
parachlorometa cresol
24 .
2-chlorophenol
25.
1,2-dichlorobenzene
26.
1,3-dichlorobenzene
28.
3,3'-dichlorobenzidine
31.
2,4-dichlorophenol
32.
1,2-dichloropropane
33.
1,3-dichloropropylene
34 .
2,4-dimethylphenol
35.
2,4-dinitrotoluene
36.
2,6-dinitrotoluene
37.
1,2-diphenylhydraz ine
38.
ethylbenzene
40.
4-chlorophenyl phenyl ether
41.
4-bromophenyl phenyl ether
42.
bis(2-chloroisopropyl) ether
43.
bis(2-chloroethoxy) methane
45.
methyl chloride
46.
methyl bromide
47 .
bromoform
49.
DELETED
50 .
DELETED
51.
chlorodibromomethane
52.
hexachlorobutadiene
53 .
hexachlorocyclopentadiene
54 .
isophorone
55 .
naphthalene
56 .
nitrobenzene
57 .
2-n it rophenol
957
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SECONDARY ALUMINUM SUBCATEGORY SECT - VI
TABLE VI-2 (Continued)
TOXIC POLLUTANTS NEVER DETECTED
58. 4-nitrophenol
59. 2,4-dinitrophenol
60. 4,6-dinitro-o-cresol
61. N-nitrosodimethylamine
62. N-nitrosodiphenylamine
63. N-nitrosodi-n-propylamine
64. pentachlorophenol
70. diethyl phthalate
72. benzo(a)anthracene
74. 3,4-benzofluoranthene
75. benzo(k)fluoranthene
78. anthracene (a)
79. benzo(ghiJperylene
80. fluorene
81. phenanthrene (a)
82. dibenzo(a,h)anthracene
83. indeno (1,2,3-cd)pyrene
86. toluene
88. vinyl chloride
89. aldrin
90. dieldrin
94. 4/4'-DDD
95. alpha-endosulfan
96. beta-endosulfan
97. endosulfan sulfate
105. delta-BHC
116. asbestos
129. 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)
(a) Reported together
958
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SECONDARY ALUMINUM SUBCATEGORY SECT - VII
SECTION VII
CONTROL AND TREATMENT TECHNOLOGIES
The preceding sections of this supplement discussed the
wastewater sources, flows, and characteristics of the wastewaters
from secondary aluminum plants. This section summarizes the
description of these wastewaters and indicates the level of
treatment which is currently practiced by in secondary aluminum
subcategory for each waste stream. Since gathering data through
data collection portfolios, the Agency has learned that 15 plants
have closed. Treatment methods used by these plants are still
presented in this section because they play an integral part in
BAT technology selection.
This section presents a summary of the control and treatment
technologies that are currently being applied to each of the
sources generating wastewater in this subcategory. As discussed
in Section V, wastewater associated with the secondary aluminum
subcategory is characterized by the presence of the toxic metal
pollutants and suspended solids. The raw (untreated) wastewater
data are presented for specific sources as well as combined waste
streams in Section V. Generally, these pollutants are present in
each of the waste streams at treatable concentrations, so these
waste streams are commonly combined for treatment to reduce the
concentrations of these pollutants. Construction of one
wastewater treatment system for combined treatment allows plants
to take advantage of economies of scale and, in some instances,
to combine streams of differing alkalinity to reduce treatment
chemical requirements. Three plants in this subcategory
currently have combined wastewater treatment systems, one has
lime precipitation and sedimentation, and no plants have lime
precipitation, sedimentation and filtration. As such, two
options have been selected for consideration for BAT, BDT, and
pretreatment in this subcategory, based on combined treatment of
these compatible waste streams.
TECHNICAL BASIS OF EXISTING REGULATIONS
As mentioned in Section III, EPA promulgated BPT effluent
limitations guidelines for the secondary aluminum smelting
subcategory on April 8, 1974. In order to put the treatment
practices currently in place and the technologies selected for
BAT options into the proper perspective, it is necessary to
describe the technologies selected by EPA for BPT, BAT, and
pretreatment standards. The BPT regulations established by EPA
limited the discharge of aluminum, copper, ammonia, chemical
oxygen demand, fluoride, and total suspended solids and required
the control of pH (refer to Section IX). The BAT regulation
required zero discharge based on in-process changes which
eliminated the need for demagging wet air pollution control and
dross washing. Zero discharge of metal cooling water was based
on 100 percent recycle. Pretreatment for existing sources
959
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SECONDARY ALUMINUM SUBCATEGORY SECT - VII
required oil skimming, pH adjustment, and ammonia air stripping.
SCRAP DRYING WET AIR POLLUTION CONTROL
Wet and dry control devices are used to control air emissions
from scrap drying operations. Three plants use scrubbers; 26
plants use baghouses. Two plants practice 100 percent recycle,
resulting in zero discharge. One plant discharges this
wastewater, which may contain suspended solids and aluminum.
Alkali addition and sedimentation can be used to remove suspended
solids and some metals. The one plant producing this wastewater
reported no treatment before discharging to a municipal sewer
system.
SCRAP SCREENING AND MILLING WASTEWATER
Two plants operate scrap screening and milling operations. Both
plants practice 100 percent reycle of this wastewater, which may
contain total suspended solids, toxic metals, and aluminum at
treatable concentrations. Alkali addition and sedimentation may
be used to reduce suspended solids and some metals.
DROSS WASHING WASTEWATER
Of the four plants that practice wet dross processing, two
practice 100 percent recycle and one attains zero discharge by
solar evaporation. Two plants recycle 67 percent of this
wastewater, which contains toxic metals, aluminum, ammonia, and
suspended solids.
The only currently practiced reduction of primary aluminum
residues and secondary aluminum slags uses wet milling with a
countercurrent flow process to reduce or possibly eliminate salt
impregnation of runoff and ground water from discarded solid
waste. Such salt recovery installations are operating in England
and Switzerland, and the salts recovered assist in paying for the
operation since they are reusable as fluxing salts in the
secondary aluminum subcategory. By using a countercurrent
milling and washing approach, two advantages are realized. The
final recovered metal is washed with clean water, providing a
low-salt feed to the melting furnaces. The wastewater, with the
insolubles removed, would be of a concentration suitable for
economical salt recovery by evaporation and crystallization.
Heat for evaporation could be supplied by the waste heat from the
furnaces. The process would have to contend with the ultimate
disposal of dirt, trace metals, and insoluble salts not removed
from the dross during milling. Sedimentation with recycle is the
treatment method currently used at the one discharging facility.
DEMAGGING WET AIR POLLUTION CONTROL
During the smelting process it is often necessary to remove
magnesium from the molten aluminum. This process of demagging
can be performed with chlorine or aluminum fluoride. Most
960
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SECONDARY ALUMINUM SUBCATEGORY SECT - VII
facilities (25 of the 37 that demag) use chlorine to accomplish
the demagging. Aluminum fluoride is more expensive than chlorine
and is not regarded as effective in removing magnesium. In
addition, the furnace refractory lining life is shorter when
aluminum fluoride is used since residues resulting from its use
in the demagging process are more corrosive than chlorine
generated residues.
However, demagging with chlorine complicates emissions control
because of the formation of hydrochloric acid in the smelting
emissions, due to the hydrolysis of aluminum and magnesium
chloride when wet scrubbing is used. Emissions from aluminum
fluoride demagging are usually controlled with dry processes.
Demagging scrubbing wastewater contains toxic metals, aluminum,
total suspended solids, and oil and grease.
Of the 58 facilities surveyed, 20 use some form of wet process
control of demagging air emissions. Four of the 20 practice 100
percent recycle. Four of the facilities discharge (either
directly or to a POTW) with no prior treatment, and one facility
only settles the waste stream before discharging it. The six
facilities that treat this waste stream all neutralize the stream
(often with soda ash) before discharge. This neutralization step
is usually followed by a settling procedure since pH adjustment
to 5.0 to 7.0 will precipitate most of the aluminum and
magnesium.
DELACQUERING WET AIR POLLUTION CONTROL
Wet scrubbers are used to control air pollution from delacquering
operations at five plants. Two plants report using
sedimentation, one plant neutralizes with caustic, and one plant
uses lime and settle treatment. The fifth plant did not report
its treatment method. Three plants reported recycle rates of 97
percent and above.
Analytical data submitted to the Agency show delacquering wet air
pollution control wastewater to contain total phenolics and
treatable concentrations of zinc. The pH of the scrubber liquor
is approximately 6.5 and TSS concentrations are typically below
70 mg/1.
INGOT CONVEYER CASTING CONTACT COOLING
Ingot molds traveling on conveyers are sprayed with water to cool
and solidify the molten metal.
Oil and grease, used to lubricate mold conveyer systems, is
washed from the equipment as the product is sprayed with water.
The quantity of ingot conveyer wastewater can be reduced by
recycle or the reuse of the water in demagging wet air pollution
control.
Casting contact cooling water contains treatable concentrations
961
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SECONDARY ALUMINUM SUBCATEGORY SECT - VII
of aluminum, oil and grease, and suspended solids.
Of the 17 facilities known to have ingot conveyer casting, only
one plant uses any sort of treatment prior to discharge.
Wastewater treatment at this plant consists of flotation and grit
removal. Recycle is practiced at three plants.
SHOT CASTING CONTACT COOLING
The manufacture of deoxidizer shot involves allowing molten
aluminum to flow through a mesh screen and fall (forming a
spherical shot product) into a quenching tank. There are four
plants known to manufacture shot, two of them are zero discharge
through holding tanks and cooling towers. Chemical treatment of
the wastewater is not practiced at any of the four plants.
CONTROL AND TREATMENT OPTIONS CONSIDERED
Based on an examination of the wastewater sampling data, two
treatment technologies that effectively control the pollutants
found in secondary aluminum wastewaters were selected for
evaluation. These technology options are discussed below.
OPTION A
Option A for the secondary aluminum subcategory is analogous to
BPT treatment with a few modifications. Option A requires
control and treatment technologies to reduce the discharge of
wastewater volume and pollutant mass. Recycle of casting contact
cooling water is the control mechanism for flow reduction.
The Option A treatment model consists of ammonia stream
stripping pretreatment applied to the dross washing wastewater
stream, activated carbon adsorption pretreatment for total
phenolics, pretreatment of casting cooling water with oil
skimming, and lime and settle technology (chemical precipitation
and sedimentation) applied to the combined stream of steam
stripper effluent, demagging air pollution scrubbing wastewater,
delacquering air pollution scrubbing wastewater, and casting
contact cooling wastewater. Chemical precipitation is used to
remove metals by 'the addition of lime followed by gravity
sedimentation: Suspended solids are also removed from the
process. Option A varies slightly from the promulgated BPT
technology in that the existing BPT requires zero discharge of
metal cooling water. Data submitted to the Agency (see Section
IX) have demonstrated the need for a blowdown from ingot conveyer
casting when demagging scrubbers are not operated. Therefore,
Option A includes 90 percent recycle of cooling water when
demagging wet air pollution control is not practiced, and 100
percent reuse when demagging wet air pollution control is
practiced.
OPTION C
Option C for the secondary aluminum subcategory consists of
962
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - VII
preliminary treatment with ammonia steam stripping, oil skimming,
activated carbon adsorption, in-process flow reduction, and the
chemical precipitation and sedimentation technology considered in
Option A plus multimedia filtration end-of-pipe technology.
Multimedia filtration is used to remove suspended solids,
including precipitates of metals, beyond the concentration
attainable by gravity sedimentation. The filter suggested is of
the mixed media type, although other forms of filters such as
rapid sand filters or pressure filters would perform
satisfactorily. The addition of filters also provides consistent
removal during periods in which there are rapid increases in
flows or loadings of pollutants to the treatment scheme.
CONTROL AND TREATMENT OPTIONS REJECTED
Prior to proposing mass limitations for the secondary aluminum
subcategory, the Agency•evaluated reverse osmosis as an end-of-
pipe treatment technology. However, reverse osmosis was rejected
because it is not demonstrated in the nonferrous metals
manufacturing subcategory, nor is it clearly transferable. The
Option F treatment scheme is discussed below.
Option F for the secondary aluminum subcategory consisted of
preliminary treatment with ammonia steam stripping and oil
skimming in-process flow reduction, chemical precipitation,
sedimentation, and multimedia filtration technology considered in
Option C with the addition of reverse osmosis and evaporation
end-of-pipe technology. Option F is used for complete recycle of
the treated water by controlling the concentration of dissolved
solids. Multiple-effect evaporation is used to dewater the brines
rejected from reverse osmosis.
963
-------
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - VIII
SECTION VIII
COSTS, ENERGY, AND NONWATER QUALITY ASPECTS
This section describes the method used to develop the costs
associated with the control and treatment technologies discussed
in Section VII for wastewaters from secondary aluminum plants.
The energy requirements of the considered options, as well as
solid waste and air pollution aspects, are also discussed in this
section.
TREATMENT OPTIONS CONSIDERED
As discussed in Section VII, two control and treatment options
are considered for treating wastewater from the secondary
aluminum subcategory. Cost estimates, in the form of annual cost
curves, have been developed for each of these control and
treatment options. The control and treatment options are
presented schematically in Figures X-l and X-2 (pages 995 and
996) and summarized below.
OPTION A
Option A for the secondary aluminum subcategory requires control
and treatment technologies to reduce the discharge of wastewater
volume and pollutant mass. The recycle of ingot conveyer casting
contact cooling water through cooling towers or 100 percent reuse
in demagging scrubbers and the recycle of scrap drying and
delacquering scrubber water through holding tanks are the control
mechanisms for flow reduction. The Option A treatment technology
consists of ammonia steam stripping preliminary treatment applied
to the dross washing wastewater stream, and oil skimming
preliminary treatment applied to the casting contact cooling
water stream. Activated carbon adsorption preliminary treatment
is required for phenolics in delacquering scrubber liquor.
Preliminary treatment is followed by lime precipitation and
sedimentation applied to the combined stream of steam stripper
effluent, casting contact cooling water, delacquering scrubber
blowdown, and demagging scrubber water.
OPTION C
Option C for the secondary aluminum subcategory consists of all
the control and treatment technologies of Option A (in-process
flow reduction through holding tanks and cooling towers, ammonia
steam stripping and oil skimming preliminary treatment, and lime
precipitation and sedimentation end-of-pipe treatment) with the
addition of multimedia filtration to the end-of-pipe treatment
scheme.
965
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SECONDARY ALUMINUM SUBCATEGORY SECT - VIII
Cost Methodology
A detailed discussion of the methodology used to develop the
compliance costs is presented in Section VIII of the General
Development Document. Plant-by-plant compliance costs have been
estimated for the secondary aluminum subcategory and are
presented in the administrative record supporting this
regulation. A comparison of the costs developed for proposal and
the revised costs for the final regulation are presented in
Tables VIII-1 and VIII-2 (pages 970 and 971) for the direct and
indirect dischargers, respectively.
Each of the major assumptions used to develop compliance costs is
presented in Section VIII of the General Development Document.
Each subcategory contains a unique set of waste streams requiring
certain subcategory-specific assumptions to develop compliance
costs. Seven major assumptions are discussed briefly below.
(1) Annual costs (except for amortized investment) for lime
and settle treatment were incurred to comply with the
promulgated BPT regulation. These costs were not
included in the current regulation if lime and settle
treatment is in place.
(2) Chemical precipitation costs were based on lime addi-
tion except for plants that currently utilize sodium
hydroxide or soda ash. In these cases, sodium
hydroxide addition was assumed for cost estimation.
(3) Activated carbon adsorption was included as a prelimi-
nary treatment step for delacquering scrubber blow-
down to control phenolics. Analytical data supplied to
the Agency indicate TSS concentrations were small enough
not to cause plugging, so pretreatment prior to enter-
ing the column was unnecessary.
(4) Ammonia steam stripping was included as a preliminary
treatment step for dross washing. Since the steam
requirements for such treatment may exceed the excess
steam generation capacity of a given plant, a steam
generation unit was included in the costs.
(5) The ingot conveyer casting contact cooling water was
routed to the demagging scrubber operation (if this
operation was present), and the costs of this routing
were included. When demagging wet air pollution control was not
practiced at the plant, compliance costs were based on
90 percent recycle through cooling towers.
(6) Recycle of air pollution control scrubber liquor was
based on recycle through holding tanks. Annual costs
associated with maintenance and sludge disposal were
included in the estimated compliance costs. Spent
activated carbon was assumed to be regenerated or dis-
posed of as a hazardous waste depending on volume
966
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SECONDARY ALUMINUM SUBCATEGORY SECT - VIII
generated. If a plant currently recycles scrubber
liquor, capital costs of the recycle equipment (piping,
pumps, and holding tanks) were not included in the
compliance costs.
(7) Capital and annual costs for plants discharging in both
the secondary and primary aluminum subcategories were
based on a combined treatment system and were appor-
tioned to each subcategory on a flow-weighted basis.
NONWATER QUALITY ASPECTS
A general discussion of the nonwater quality aspects of the
control and treatment options considered for the nonferrous
metals category is contained in Section VIII of the General
Development Document. Nonwater quality impacts specific to the
secondary aluminum subcategory including energy requirements,
solid waste, and air pollution are discussed below.
ENERGY REQUIREMENTS
The methodology used for determining the energy requirements for
the various options is discussed in Section VIII of the General
Development Document. Implementation of Option A technology is
estimated to require 2.4 MW-hr/yr, while Option C would require
2.5 MW-hr/yr for the subcategory. At a typical secondary
aluminum plant, Option A represents a 2.3 percent increase in
overall electrical consumption, and Option C represents a 2.4
percent increase in overall electrical consumption. Therefore,
it is concluded that the technology options considered will have
a minimal impact on energy consumption in the secondary aluminum
subcategory.
SOLID WASTE
Sludges associated with the secondary aluminum subcategory will
necessarily contain toxic quantities (and concentrations) of
toxic metal pollutants. The Agency examined the solid wastes
that would be generated at secondary aluminum plants by lime,
settle, and filter treatment technologies and believes they are
not hazardous wastes under the Agency's regulations implementing
Section 3001 of the Resource Conservation and Recovery Act. None
of these wastes is listed specifically as hazardous. Nor are
they likely to exhibit a characteristic of hazardous waste. By
the addition of excess lime during treatment, similar sludges,
specifically toxic metal bearing sludges, generated in other
industrial categories such as the iron and steel and
electroplating categories, passed the Extraction Procedure (EP)
toxicity test. See 40 CFR S261.24. Thus, the Agency believes
that the wastewater sludges will similarly not be EP toxic if the
recommended technology is applied.
Certain secondary aluminum plants also will generate spent
activated carbon which will be contaminated with phenols. Such
spent carbon is not listed as a hazardous waste and would be
967
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SECONDARY ALUMINUM SUBCATEGORY SECT - VIII
unlikely to exhibit a characteristic of hazardous waste.
Nevertheless, the Agency has included costs for disposing of
spent carbon as a hazardous waste, or (where volumes justify the
practice) of regenerating it. Spent carbon is not currently
subject to RCRA regulation when stored before recycling. See 40
CFR 8261.6(a).
Although it is the Agency's view that solid wastes generated as a
result of these guidelines are not expected to be hazardous,
generators of these wastes must test the waste to determine if
the wastes meet any of the characteristics of hazardous waste
(see 40 CFR 262.11).
If these wastes should be identified or are listed as hazardous,
they will come within the scope of RCRA's "cradle to grave"
hazardous waste management program, requiring regulation from the
point of generation to point of final disposition. EPA's
generator standards require generators of hazardous nonferrous
metals manufacturing wastes to meet containerization, labeling,
record keeping, and reporting requirements. If plants dispose of
hazardous wastes off-site, they are required to prepare a
manifest which tracks the movement of the wastes from the
generator's premises to a permitted off-site treatment, storage,
or disposal facility. See 40 CFR 262.20 (45 FR 33142, May 19,
1980, as amended at 45 FR 86973, December 31, 1980). The
transporter regulations require transporters of hazardous wastes
to comply with the manifest system to assure that the wastes are
delivered to a permitted facility. (See 40 CFR 263.20 45 FR
33151, May 19, 1980, as amended at 45 FR 86973, December 31,
1980). Finally, RCRA regulations establish standards for
hazardous waste treatment, storage, and disposal facilities
allowed to receive such wastes. (See 40 CFR Part 264, 46 FR
2802, January 12, 1981, 47 FR 32274, July 26, 1982).
Even if these wastes are not identified as hazardous, they still
must be disposed of in compliance with the Subtitle D open
dumping standards, implementing 4004 of RCRA. (See 44 FR 53438,
September 13, 1979). The Agency has calculated as part of the
costs for wastewater treatment the cost of hauling and disposing
of these wastes. The Agency estimates implementation of lime and
settle technology will generate approximately 11,000 tons per
year of wastewater treatment sludge. Treatment of delacquering
wet air pollution control will generate approximately 177 pounds
per year of spent carbon. Multimedia filtration technology will
not result in any significant amount of sludge over that
generated by lime precipitation.
AIR POLLUTION
There is no reason to believe that any substantial air pollution
problems will result from implementation of ammonia steam
stripping, oil skimming, chemical precipitat ion, sedimentation,
and multimedia filtration. These technologies transfer
pollutants to solid waste and do not involve air stripping or any
other physical process likely to transfer pollutants to air.
968
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SECONDARY ALUMINUM SUBCATEGORY SECT - VIII
Water vapor containing some particulate matter will be released
in the drift from the cooling tower systems which are used as the
basis for flow reduction in the secondary aluminum subcategory.
However, the Agency does not consider this impact to be
signi ficant.
969
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SECONDARY ALUMINUM SUBCATEGORY SECT - VIII
Table VIII-1
COST OF COMPLIANCE FOR THE SECONDARY ALUMINUM SUBCATEGORY
DIRECT DISCHARGERS*
Proposal Promulgation
Option Capital Cost Annual Cost Capital Cost Annual Cost
A 2,000,000 1,800,000 1,000,000 600,000
C 2,200,000 1,900,000 1,100,000 640,000
*1982 dollar
970
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SECONDARY ALUMINUM SUBCATEGORY SECT - VIII
Table VIII-2
COST OF COMPLIANCE FOR THE SECONDARY ALUMINUM SUBCATEGORY
INDIRECT DISCHARGERS*
Proposal Promulgation
Opt ion Capital Cost Annual Cost Capital Cost Annual Cost
A 3,000,000 2,000,000 2,100,000 1,300,000
C 3,300,000 2,200,000 2,300,000 1,400,000
*1982 dollars
971
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SECONDARY ALUMINUM SUBCATEGORY SECT - IX
SECTION IX
BEST PRACTICABLE CONTROL TECHNOLOGY CURRENTLY AVAILABLE
EPA promulgated best practicable control technology currently
available (BPT) effluent limitations standards for the secondary
aluminum industry on April 8, 1974 as Subpart C of 40 CFR Part
421. Pollutants regulated by these standards are aluminum,
copper, chemical oxygen demand, ammonia, fluoride, TSS, and pH.
Unlike the current rulemaking, the BPT standards were developed
on the basis of two subdivisions of the secondary aluminum
process, not on the basis of segments that isolate individual
wastewater streams. BPT standards were established for magnesium
removal processes (demagging using either chlorine or aluminum
fluoride) and wet residue processes. The effluent limitations
established by the 1974 BPT standards also require zero discharge
of metal cooling water.
(a) The following limitations establish the quantity or
quality of pollutants or pollutant properties, which
may be discharged by a point source subject to the
provisions of this subpart and which uses water for
metal cooling, after application of the best practi-
cable control technology currently available: There
shall be no discharge of process wastewater pollutants
to navigable waters.
(b) The following limitations establish the quantity or
quality of pollutants or pollutant properties which may
be discharged by a point source subject to the provi-
sions of this subpart and which uses aluminum fluoride
in its magnesium removal process ("demagging process"),
after application of the best practicable control
technology currently available: There shall be no
discharge of process wastewater pollutants to navi-
gable waters.
(c) The following limitations establish the quantity or
quality of pollutants or pollutant properties con-
trolled by this section, which may be discharged by
a point source subject to the provisions of this
subpart and which uses chlorine in its magnesium
removal process, after application of the best
practicable control technology currently available:
973
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SECONDARY ALUMINUM SUBCATEGORY SECT - IX
Effluent Limitations
Effluent Average of daily values for 30 consecutive
Characteristic days shall not exceed
Metric units (kilograms per 1,000 kg
magnesium removed)
English units (lbs per 1/000 lbs
magnesium removed)
TSS 175
COD 6.5
pH Within the range of 7.5 to 9.0
(d) The following limitations establish the quantity or
quality of pollutants or pollutant properties which
may be discharged by a point source subject to the
provisions of this subpart and which processes resi-
dues by wet methods/ after application of the best
practical control technology currently available:
Effluent Limitations
Effluent Average of daily values for 30 consecutive
Characteristic days shall not exceed
Metric units (kilograms per 1,000 kg
magnesium removed)
English units (lbs per 1,000 lbs
magnesium removed)
TSS 1.5
Fluoride- 0.4
Ammonia (as N) 0.01
Aluminum 1.0
Copper 0.00 3
COD 1.0
pH Within the range of 7.5 to 9.0
974
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SECONDARY ALUMINUM SUBCATEGORY SECT - X
SECTION X
BEST AVAILABLE TECHNOLOGY ECONOMICALLY ACHIEVABLE
The effluent limitations are based on the best control and
treatment technology used by a specific point source within the
industrial category or subcategory, or by another industry where
it is readily transferable. Emphasis is placed on additional
treatment techniques applied at the end of the treatment systems
currently used for BPT, as well as reduction of the amount of
water used and discharged, process control, and treatment
technology optimization.
The factors considered in assessing best available technology
economically achievable (BAT) include the age of equipment and
facilities involved, the process used, process changes, nonwater
quality environmental impacts (including energy requirements),
and the costs of application of such technology (Section 304(b)
(2)(B) of the Clean Water Act). At a minimum, BAT represents the
best available technology economically achievable at plants of
various ages, sizes, processes, or other characteristics. Where
the Agency has found the existing performance to be uniformly
inadequate, BAT may be transferred from a different subcategory
or category. BAT may include feasible process changes or
internal controls, even when not in common industry practice.
The required assessment of BAT considers costs, but does not
require a balancing of costs against effluent reduction benefits
(see Weyerhaeuser v. Costle, 590 F.2d. 1011 (D.C. Cir. 1978)).
However, in assessing the proposed BAT, the Agency has given
substantial weight to the economic achievability of the
technology.
On April 8, 1974, EPA promulgated technology-based BAT effluent
limitations guidelines for the secondary aluminum subcategory.
BAT required zero discharge based on 100 percent recycle of
casting contact cooling water and in-process changes which
eliminate demagging wet air pollution control and residue milling
(dross washing). Elimination of demagging scrubbers was based on
the installation of the Durham process, ALCOA process, and the
Teller process, which significantly reduces fuming during
demagging and the need for wet scrubbers. The Agency believed
that each of these processes was sufficiently well demonstrated
to be installed and become operational by 1984. Consequently,
there was no justification for a discharge allowance associated
with this waste stream. However, new information shows that the
technologies are not sufficiently demonstrated nor are they
applicable to plants on a nationwide basis.
A similar situation exists for dross washing. Zero discharge for
this operation was based on demonstrated dry milling in the
subcategory. However, the extensive retrofits of installing dry
milling have prompted EPA to reevaluate the existing BAT zero
975
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SECONDARY ALUMINUM SUBCATEGORY SECT - X
discharge requirement. For these reasons, the existing BAT is
modified to allow a discharge for demagging wet air pollution
control and dross washing.
TECHNICAL APPROACH TO BAT
In pursuing this second round of effluent regulations, EPA
reviewed a wide range of technology options and evaluated the
available possibilities to ensure that the most effective and
beneficial technologies were used as the basis of BAT. To
accomplish this, the Agency elected to examine two technology
alternatives which could be applied to the secondary aluminum
subcategory as BAT options.
In summary/ the treatment technologies considered for BAT are
presented below:
Option A (Figure X-l, page 995) is based on
o Preliminary treatment with oil skimming (where required)
o Preliminary treatment of dross washing wastewater with
ammonia steam stripping
o Preliminary treatment of delacquering wet air pollution
control wastewater with activated carbon adsorption
o In-process flow reduction of casting contact cooling
water and scrubber liquor resulting from scrap drying and
delacquering wet air pollution control
o Chemical precipitation and sedimentation
Option C (Figure X-2, page 996) is based on
Preliminary treatment with oil skimming (where required)
Preliminary treatment of dross washing wastewater with
ammonia steam stripping
o Preliminary treatment of delacquering wet air pollution
control wastewater with activated carbon adsorption
o In-process flow reduction of ca'sting contact cooling
water and scrubber liquor resulting from scrap drying and
delacquering wet air pollution control
o Chemical precipitation and sedimentation
o Multimedia filtration
The two options for BAT are discussed in greater detail below.
The first option considered is analogous to the BPT treatment and
control technology.
OPTION A
Option A requires control and treatment techologies to reduce the
discharge of wastewater volume and pollutant mass. These
measures include in-process changes, resulting in the elimination
of some wastewater streams and the concentration of pollutants
in other effluents. As explained in Section VII of the General
Development Document, treatment of a more concentrated effluent
o
o
976
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - X
allows achievement of a greater net pollutant removal and
introduces the possible economic benefits associated with
treating a lower volume of wastewater. Methods used in Option A
to reduce process wastewater generation or discharge rates
include the following:
Recycle of Casting Contact Coolinq Water
The function of casting contact cooling water is to quickly
remove heat from the newly formed ingot or bar. Therefore, the
principal requirements of the water are that it be cool and not
contain dissolved solids at a concentration that would cause
water marks or other surface imperfections. There is sufficient
category experience with casting contact cooling wastewaters to
assure the success of this technology using cooling towers or
heat exchangers (refer to Section VII of the General Development
Document). A blowdown or periodic cleaning is likely to be
needed to prevent a build-up of dissolved and suspended solids.
(EPA has determined that a blowdown of 10 percent of the water
applied in a process is adequate.)
Reuse of casting contact cooling water is also an effective means
of reducing flow. One plant in the secondary aluminum
subcategory has demonstrated that ingot conveyer casting contact
cooling water can be reused as demagging scrubber liquor make-up.
EPA knows of no engineering reason why this water is unsuitable
for make-up water to the demagging scrubber.
Recycle of Water Used in Wet Air Pollution Control
There are three wastewater sources associated with wet air
pollution control which are regulated under these effluent
limitations:
1. Delacquering,
2. Scrap drying, and
3. Demagging.
Table X-l (page 987)presents the number of plants reporting
wastewater use with these sources, the number of plants
practicing recycle of scrubber liquor, and the range of recycle
values being used.
The Option A treatment model includes in-process flow reduction,
steam stripping and activated carbon adsorption preliminary
treatment of wastewaters containing ammonia and phenolics at
treatable concentrations and oil skimming, where required.
Preliminary treatment is followed by chemical precipitation and
sedimentation (see Figure X-l, page 987). Although oil and
grease is a conventional pollutant limited under best practicable
technology (BPT), oil skimming is needed for BAT to ensure proper
metals removal. Oil and grease interferes with the chemical
addition and mixing required for chemical precipitation
treatment. Chemical precipitation is used to remove metals by
the addition of lime followed by gravity sedimentation.
977
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SECONDARY ALUMINUM SUBCATEGORY SECT - X
Suspended solids are also removed from the process.
OPTION C
Option C for the secondary aluminum subcategory builds upon the
Option A control and treatment technology of in-process flow
reduction, oil skimming (where required), ammonia steam
stripping, activated carbon adsorption, chemical precipitation,
and sedimentation by adding multimedia filtration technology at
the end of the Option A treatment scheme (see Figure X-2, page
988). Multimedia filtration is used to remove suspended solids,
including precipitates of metals, beyond the concentration
attainable by gravity sedimentation. The filter suggested is of
the gravity, mixed media type, although other forms of filters,
such as rapid sand filters or pressure filters, would perform
satisfactorily.
INDUSTRY COST AND POLLUTANT REMOVAL ESTIMATES
As a means of evaluating each technology option, EPA developed
estimates of the pollutant removal estimates and the compliance
costs associated with each option. The methodologies are
described below.
POLLUTANT REMOVAL ESTIMATES
A complete description of the methodology used to calculate the
estimated pollutant reduction achieved by the application of the
various treatment options is presented in Section X of the
General Development Document. The pollutant removal estimates
have been revised from proposal based on comments and new data.
However, the methodology for calculating pollutant removals has
not changed. The data used for estimating pollutant removals are
the same as those used to revise the compliance costs.
Sampling data collected during the field sampling program were
used to characterize the major waste streams considered for
regulation. At each sampled facility, the sampling data were
production normalized for each unit operation (i.e., mass of
pollutant generated per mass of product manufactured). This
value, referred to as the raw waste, was used to estimate the
mass of toxic pollutants generated within the secondary aluminum
subcategory. By multiplying the total subcategory production for
a unit operation by the corresponding raw waste value, the mass
of pollutant generated for that unit operation was estimated.
The volume of wastewater discharged after the application of each
treatment option was estimated for each operation at each plant
by comparing the actual discharge to the regulatory flow. The
smaller of the two values was selected and summed with other
plant flows. The mass of pollutant discharged was then estimated
by multiplying the achievable concentration values attainable by
the option (mg/1) by the estimated volume of process wastewater
discharged by the subcategory. The mass of pollutant removed is
simply the difference between the estimated mass of pollutant
978
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SECONDARY ALUMINUM SUBCATEGORY SECT - X
generated within the subcategory and the mass of pollutant
discharged after application of the treatment option. Pollutant
removal estimates for the secondary aluminum direct dischargers
are presented in Table X-2 (page 988).
COMPLIANCE COSTS
Compliance costs presented at proposal were estimated using cost
curves, which related the total costs associated with
installation and operation of wastewater treatment technologies
to plant process wastewater discharge. EPA applied these curves
on a per plant basis, a plant's costs (both capital/ and
operating and maintenance) being determined by what treatment it
has in-place and by its individual process wastewater discharge
(from dcp). The final step was to annualize the capital costs,
and to sum the annualized capital costs, and the operating and
maintenance costs, yielding the cost of compliance for the
subcategory.
Since proposal, the cost estimation methodology has been changed
as discussed in Section VIII of this supplement. A design model
and plant-specific information were used to size a wastewater
treatment system for each discharging facility. After completion
of the design, capital and annual costs were estimated for each
unit of the wastewater treatment system. Capital costs rely on
vendor quotes, while annual costs were developed from the
literature. The revised compliance costs for direct dischargers
are presented in Table VIII-1 (page 970).
BAT OPTION SELECTION
EPA has selected Option C as the basis of BAT in this
subcategory. The BAT treatment scheme proposed consists of flow
reduction, oil skimming (where required), preliminary treatment
of ammonia steam stripping and activated carbon, lime
precipitation, sedimentation, and filtration for control of toxic
metals. The selected option increases the removal of toxic
pollutants from raw wastewater by approximately 9,600 kg/yr, 530
kg/yr of phenolics, and nonconventional pollutants by
approximately 90,800 kg/yr. This option also removes
approximately 8.2 kg/yr of toxic pollutants and 36 kg/yr of
nonconventional pollutants over the estimated BPT discharge. The
estimated capital cost of proposed BAT is $1.1 million (1982
dollars) and the annual cost is $0.64 million (1982 dollars).
Ammonia steam stripping is demonstrated in the nonferrous metals
manufacturing category by two plants in the primary columbium-
tantalum subcategory, and three plants in the primary tungsten
subcategory. Activated carbon is not demonstrated in the
subcategory, but it is a classic means of removing phenols from
wastewater.
Activated carbon is demonstrated in the iron and steel
(cokemaking) category as a phenols removal technology. The
treatment performance used for activated carbon to develop mass
979
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SECONDARY ALUMINUM SUBCATEGORY SECT - X
limitations for total phenolics is based on the attainable
quantification limit of 0.010 mg/1. EPA believes this value is
achievable when adequate quantities of carbon are used.
At the source requirements (i.e., requiring that compliance be
demonstrated and monitoring conducted prior to commingling with
process or nonprocess waters) are promulgated for phenol in
delacquering wet air pollution control wastewaters. This is
because there is a distinct possibility that plants may be able
to meet the limits for toxic organics through dilution unless the
compliance point is at-the-source, rather than end-of-pipe. This
is because the organic pollutants are present in wastewater from
only certain unit operations, and are present at concentrations
that could be reduced below the analytical detection levels after
commingling with other process wastewaters. The plants known to
currently operate delacquering scrubbers are principally primary
aluminum and aluminum forming plants, which generate much larger
volumes of process wastewater than the delacquering operation.
Therefore# at-the-source requirements are promulgated to prevent
dilution.
Carbon adsorption may require preliminary treatment to remove
suspended solids and oil and grease. Suspended solids
concentrations in the influent should be reduced to minimize
backwash requirements. Four sample analyses of delacquering
scrubber liquor submitted to the Agency showed suspended solids
concentrations of 22, 9.0, 17.2, and 60.8 mg/1.
These concentrations are essentially those achievable with lime
and settle treatment (19.5 mg/1 ten day average). Therefore, it
appears pretreatment for TSS is not required prior to activated
carbon adsorption pretreatment. Oil and grease data were not
submitted.
Since filtration removes additional toxic and nonconventional
pollutants, and is economically achievable, it is included as
part of proposed BAT. Filtration also adds to the treatment
system reliability by making it less susceptible to operator
error and to sudden changes in raw wastewater flows and
concentrations. Further, the selection of filters is an
appropriate balance to the elimination of previously promulgated
no discharge BAT requirements for ingot conveyer casting and
dross washing. Providing these two allowances is only justified
when the Agency can assume that most of the pollutants contained
in these discharges will be removed by treatment.
For the Secondary Aluminum Subcategory, EPA promulgated final
amendments on July 7, 1987 (52 FR 25552) to the regulation
concerning two topics, which are described here.
EPA has amended the flow basis for two subdivisions based on a
re-evaluation of data available in the Administrative Record for
this rulemaking. These two subdivisions are ingot conveyer
casting and demagging wet air pollution control.
980
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - X
WASTEWATER DISCHARGE RATES
Specific wastewater streams associated with the secondary
aluminum subcategory are generated from scrap drying air
pollution control, scrap screening and milling, dross washing,
demagging wet air pollution control, delacquering wet air
pollution control, direct chill casting contact cooling, ingot
conveyer casting contact cooling, shot casting contact cooling,
and stationary casting contact cooling.
Table X-3 (page 989) lists the production normalized wastewater
discharge rates allocated at BAT for these wastewater streams.
The values represent the best existing practices of the industry,
as determined from the analysis of dcps. Individual discharge
rates from the plants surveyed are presented in Section V of this
supplement for each wastewater stream.
SCRAP DRYING WET AIR POLLUTION CONTROL WASTEWATER
No BAT wastewater discharge allowance was proposed for scrap
drying air pollution control. Only three of 29 plants use
scrubbers to control emissions; the remaining 26 plants use
baghouses. Two of the three plants with scrubbers achieve zero
discharge by 100 percent recycle. One plant is a once-through
discharger with a rate of 1,057 1/kkg (253.5 gal/ton) of aluminum
scrap produced. This plant also reported that it planned to
discontinue the use of the scrubber. Wastewater rates are
presented in Section V (Table V-l, page 912). The BAT allowance
is zero discharge of wastewater pollutants based on the
attainment of no discharge by 28 of 29 plants, including two of
the three operations using wet air pollution control. No data or
information were submitted to the Agency demonstrating zero
discharge as proposed is not attainable.
SCRAP SCREENING AND MILLING
No BAT wastewater discharge rate was proposed for scrap screening
and milling. Both plants reporting this wastewater are zero
dischargers because of 100 percent recycle or reuse. Therefore,
the Agency believes that zero discharge is possible for all
secondary aluminum scrap screening and milling processes. No
data or information were submitted to the Agency demonstrating a
discharge allowance is needed for scrap screening and milling.
DROSS WASHING WASTEWATER
The proposed BAT wastewater discharge rate was 10,868 1/kkg
(2,607 gal/ton) of dross processed. Four plants reported
producing this wastewater. Two plants discharge from the process
after 67 percent recycle. One plant completely evaporates this
wastewater. The BAT rate is the discharge from plant 4104. Two
plants recycle 100 percent of the wastewater. No data or
information were submitted to the Agency demonstrating that the
proposed discharge allowance was not appropriate; therefore, the
promulgated discharge rate is equal to that proposed. EPA
981
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - X
considers the zero discharge practices for this waste stream to
be site-specific and not applicable on a nationwide basis.
Wastewater rates for dross washing are presented in Section V
(Table V-3, page 914).
DEMAGGING WET AIR POLLUTION CONTROL
The proposed BAT wastewater discharge rate was 800 1/kkg (192
gal/ton) of aluminum demagged. This rate is allocated only for
plants practicing wet air pollution control of demagging
operations. Of the 37 demagging operations reported, 20 use
water for emissions control. Nine plants using water reported no
wastewater discharge, achieved by recycle or reuse. Eight of the
nine plants completely recycle the wastewater, while one plant
did not report a recycle percentage. Another plant practices a
partial recycle of 40 percent. Nine plants were thought to have
once-through operations, eight of these discharging 223.3 to
1,956.24 1/kkg (54.5 to 469.2 gal/ton). No flow data were
provided by one of the discharging plants. A distribution of
wastewater rates considered is presented in the proposed
secondary aluminum supplemental development document. Industry
comments prior to proposal asserted that the use of recirculation
systems using treated water reduces demagging scrubber
efficiency. Therefore, recycle of scrubber liquor was not used
as a basis for the BAT discharge rate for demagging wet air
pollution control. The BAT discharge rate was based on the
average of the nine discharging plants.
Commenters on the proposed mass limitations questioned the
reported 100 percent recycle of demagging scrubber liquor in the
proposed supplemental development document. In addition,
commenters questioned the calculation of the demagging scrubber
discharge allowance. Based on these comments, the Agency
re-evaluated the discharge rate for demagging scrubber liquor.
Four plants were identified and confirmed to achieve zero
discharge of demagging scrubber liquor. Zero discharge at these
plants is site-specific and not appropriate on a national basis.
A blowdown from demagging scrubbers is required to control
chloride concentrations in the scrubber liquor. Those plants
reporting zero discharge recycle from ponds with large
capacitites and they may also be losing water through
percolation.
The most predominant scrubber used for demagging is the Intecbell
scrubber. Three plants reported using venturi scrubbers and one
plant uses a packed tower. Water use between these three
scrubbers is not significantly different; therefore, all data
were considered together in selecting the BAT discharge rate. The
promulgated BAT discharge rate was 697 1/kkg of aluminum
demagged. This rate represented the average water use at those
plants using less than 6,885 1/kkg. Two plants were above this
rate, and they were not considered because they use an
inordinately large amount of scrubber liquor when compared to the
other plants.
982
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - X
The Agency has amended the flow rate for demagging wet air
pollution control upon which are based the BAT limitations and
NSPS, PSES, and PSNS for the demagging wet air pollution control
subdivision. Secondary aluminum petitioners claimed that the
control flow allowance of 697 1/kkg was incorrect due to a data
interpretation error regarding the number of scrubbers associated
with the water usage for one facility. The Agency agrees that it
made an error in this calculation and has adjusted the water
usage for this plant upwards. As a result, the final regulatory
flow allowance is 771 1/kkg.
DELACQUERING WET AIR POLLUTION CONTROL
A BAT discharge rate has been added to account for wastewater
associated with wet scrubbing of air pollution generated through
the recycle of aluminum cans. Five plants reported the use of
this scrubber as shown in Table V-7. The BAT discharge rate is
based on the average reported discharge for plants 505, 313, and
4101. Each of these plants practices recycle of 97 percent or
greater and uses a venturi scrubber. The BAT discharge rate is
80 1/kkg. Plant 340 was not included in the average because it
uses a rotoclone scrubber. Water discharged for plant 340 with
no recycle compares well with the plants practicing recycle.
DIRECT CHILL CASTING CONTACT COOLING WATER
The BAT wastewater discharge rate for direct chill casting
contact cooling water was proposed as 1,999 1/kkg (479.4 gal/ton)
of aluminum cast. Direct chill casting practices and the
wastewater discharge from this operation are similar in aluminum
forming, primary aluminum reduction and secondary aluminum
plants. The information available does not indicate any
significant difference in the amount of water required for direct
chill casting in primary aluminum, secondary aluminum and
aluminum forming plants. For this reason, available wastewater
data from aluminum forming and primary aluminum plants were
considered together in establishing BPT effluent limitations. No
data for direct chill casting water use were provided by
secondary aluminum plants.
In all, 26 primary aluminum plants and 61 aluminum forming plants
have direct chill casting operations. Recycle of the contact
cooling water is practiced at 30 aluminum forming and eight
primary aluminum plants. Of these, eight plants indicated that
total recycle of this stream made it possible to avoid any
discharge of wastewater; however, the majority of the plants
discharge a bleed stream. The discharge flow for this operation
was based on the average of those plants practicing 50 percent
recycle or greater.
The Agency was in error in this determination (as pointed out by
a commenter from the aluminum industry) as it considers 90
percent recycle or greater BAT technology. (See 48 FR at 7052,
Feb. 17, 1983). Therefore, the BAT discharge allowance has been
recalculated based on those plants (both primary aluminum and
983
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - X
aluminum forming) that have recycle rates between 90 and 100
percent. The revised BAT discharge rate is thus 1,329 1/kkg (319
gal/ton) of aluminum cast. Although there are no reported
secondary aluminum plants with direct chill casting, the Agency
will promulgate mass limitations for this segment. It is
possible new or existing sources may install direct chill casting
in the future.
INGOT CONVEYER CASTING CONTACT COOLING WATER
In the proposed guidelines for this subcategory, ingot conveyer
casting was considered stationary casting because of the
promulgated zero discharge for metal cooling in the existing BPT
and BAT effluent limitations. However, information and data
submitted to the Agency indicate zero discharge of ingot conveyer
casting is not demonstrated except when the discharge is recycled
to a demagging air pollution scrubber. Therefore, a discharge
allowance was provided in the promulgated regulation for ingot
conveyer casting. The discharge rate, based on 90 percent
recycle, was 43 1/kkg (10.3 gal/ton) of aluminum cast. This rate
was based on the average water usage with the exception of plants
309 and 326. Data from these two plants were not used because of
excessive water use as determined through comparison with the
other plants. Only those plants not operating demagging scrubbers
are provided the ingot conveyer casting allowance. One hundred
percent reuse of casting water or demagging scrubber make-up
water is demonstrated at one secondary aluminum facility.
The Agency has amended the flow rate upon which the BAT
limitations and NSPS, PSES, and PSNS for ingot conveyer casting
are based. Petitioners claimed that the regulatory flow
allowance of 43 1/kkg was incorrect due to data interpretation
mistakes and because the Agency unnecessarily excluded the water
usage of plants that reported achieving zero discharge. EPA has
promulgated an amended flow allowance of 67 1/kkg, which is based
on corrected water usage data from five plants (these data
involving water usage and operating schedules which were
interpreted incorrectly by the Agency in constructing the flow
allowance in the final rule) and includes three plants' water
usage that reported achieving zero discharge. This is consistent
with EPA's methodology employed throughout the nonferrous metals
rulemaking, where the Agency typically used water usage at zero
discharge plants in determining what degrees of flow reduction
represent BAT, PSES, NSPS, and PSNS.
STATIONARY CASTING CONTACT COOLING WATER
No BAT wastewater discharge allowance is provided for stationary
casting cooling. In the stationary casting method, molten
aluminum is poured into cast iron molds and then generally
allowed to air cool. The Agency is aware of the use of spray
quenching to quickly cool the surface of the molten aluminum
once it is cast into the molds; however, this water evaporates on
contact with the molten aluminum. As such, the Agency believes
that there is no basis for a pollutant discharge allowance.
984
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - X
SHOT CASTING CONTACT COOLING WATER
No BAT wastewater discharge allowance is provided for shot
casting contact cooling. Through information requests the Agency
has found zero discharge of shot casting cooling water
demonstrated at two secondary aluminum facilities (of the four
reporting the practice). Both of these plants reported no
product quality constraints due to 100 percent recycle. Based on
the demonstrated zero discharge practices for shot casting, the
promulgated flow allowance requires zero discharge of process
wastewater pollutants.
REGULATED POLLUTANT PARAMETERS
In implementing the terms of the Clean Water Act Amendments of
1977, the Agency placed particular emphasis on the toxic
pollutants. The raw wastewater concentrations from individual
operations and the subcategory as a whole were examined to select
certain pollutants and pollutant parameters for consideration for
limitation. This examination and evaluation, presented in
Section VI, concluded that 10 pollutants and pollutant
parameters are present in secondary aluminum wastewaters at
concentrations that can be effectively reduced by identified
treatment technologies.
However, the cost associated with analysis for toxic metal
pollutants has prompted EPA to develop an alternative method for
regulating and monitoring toxic pollutant discharges from the
nonferrous metals manufacturing category. Rather than developing
specific effluent mass limitations and standards for each of the
toxic metals found in treatable concentrations in the raw
wastewaters from a given subcategory, the Agency is promulgating
effluent mass limitations only for those pollutants generated in
the greatest quantities as shown by the pollutant removal
estimate analysis. The pollutants selected for specific
limitation are listed below:
122. lead
128. zinc
total phenols (4-AAP)
aluminum
ammonia
By establishing limitations and standards for certain toxic metal
pollutants, dischargers will attain the same degree of control
over toxic metal pollutants as they would have been required to
achieve had all the toxic metal pollutants been directly limited.
This approach is justified technically since the treatable
concentrations used for lime precipitation and sedimentation
technology are based on optimized treatment for concomitant
multiple metals removal. Thus, even though metals have somewhat
different theoretical solubilities, they will be removed at very
nearly the same rate in a lime precipitation and sedimentation
985
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SECONDARY ALUMINUM SUBCATEGORY SECT - X
treatment system operated for multiple metals removal.
Filtration as part of the technology basis is likewise justified
because this technology removes metals non-preferentially. Thus,
cadmium is excluded from limitation on the basis that it is
effectively controlled by the limitations developed for lead and
zinc.
The toxic metal pollutants selected for specific limitation in
the secondary aluminum subcategory to control the discharges of
toxic metal pollutants are lead and zinc. Ammonia and total
phenolics are also selected for limitation since the methods used
to control lead and zinc are not effective in the control of
ammonia and total phenolics.
In Section VI, phenol was selected for further consideration for
limitation. However, data submitted to the Agency are primarily
in the form of total phenolics. Since phenol is contained in the
total phenolics analysis, limitation of total phenols will also
control the toxic pollutant phenol.
EFFLUENT LIMITATIONS
The treatable concentrations achievable by application of the BAT
treatment are discussed in Section VII of this supplement. The
treatable concentrations (both one day maximum and monthly
average values) are multiplied by the BAT normalized discharge
flows summarized in Table X-3 (page 989) to calculate the mass of
pollutants allowed to be discharged per mass of product. The
results of these calculations in milligrams of pollutant per
kilogram of product represent the BAT effluent limitations and
are presented in Table X-4 (page 990) for each waste stream.
986
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SECONDARY ALUMINUM SUBCATEGORY SECT - X
Table X-1
CURRENT RECYCLE PRACTICES WITHIN THE SECONDARY ALUMINUM
SUBCATEGORY
Waste Stream
Delacquering Wet Air
Pollution Control
Scrap Drying Wet Air
Pollution Control
Demagging Wet Air
Pollution Control
Ingot Conveyor Casting
Shot Casting
Number of
Plants With
Wastewater
3
20
1 7
U
Number of
Plants
Practicing
Recycle
Range of
Recycle
Values (%)
97 - 98
100
40 - 100
50 - 96
100
987
-------
POLLUTANT REMOVAL ESTIMATES
Table X-2
FOR SECONDARY ALUMINUM DIRECT DISCHARGERS
10
00
00
POLLUTANT
TOTAL
RAW WASTE
(kg/yr)
OPTION A
DISCHARGED
(kg/yr)
OPTION A
REMOVED
(kg/yr)
OPTION C
DISCHARGED
(kg/yr)
OPTION C
REMOVED
(kg/yr)
Cadralum
8,500.0
3.8
8.496.2
2.4
8,497.6
Lead
400.1
5.8
394.4
3.H
396.3
Zinc
704.6
15.8
688.8
11 .0
693.6
TOTAL TOXIC METALS
9,604.7
25.4
9.579.3
17.2
9.587.5
Phenollcs (4-AAP)
576.0
0.5
525.5
0.5
525.5
Alumlnum
90,366.8
107.5
90,259.3
71 .5
90,295.3
TOTAL NONCONVENTIONALS
90,892.7
108.0
90. 784. 7
72.0
90.820.7
TSS
198,351 .1
575.9
1 97 , 7 75 .2
124.8
198.226.3
Oil k Crease
1 2,613.6
479.9
1 2.IJ 3. 7
479.9
12,133.7
TOTAL C0NVENT10NALS
210.964.7
1.055.8
209,909.0
604.7
210. 360.1
TOTAL POLLUTANTS
31 1 .462.2
1.189.1
310,273.0
693.9
310,768.3
FLOW (l/yr)
4 7,990,000
4 7.990,000
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NOTE: TOTAL TOXIC MKTAl.S - Cadmium + Lend + Zinc
TOTAL N0NC0NVENT10NALS - Aluminum + Phenollea
TOTAL C0NVENT10NALS - TSS » 011 k Grease
TOTAL POLLUTANTS = Total Toxic Metals ~ Total NonconventlonaIs + Total Convent 1ona19
OPTION A - Oil Skimming, Ammonia Steam Stripping, Activated Carbon Adsorption, In-process Flow Reduction,
and Lime Precipitation and Sedimentation
OPTION C " Option A, plus Multimedia Filtration
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Table X-3
BAT WASTEWATER DISCHARGE RATES FOR THE SECONDARY ALUMINUM SUBCATEGORY
l£>
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l£>
Waste Stream
Scrap Drying Wet Air Pollution
Control
Scrap Screening and Milling
Dross Washing
Demagging Wet Air Pollution
Control
Delacquering Wet Air Pollution
Control
Direct Chill Casting Contact
Cooling
Ingot Conveyor Casting Contact
Cooling (When Chlorine Demag-
ging Wet Air Pollution Control
is Not Practiced On-Site)
Ingot Conveyor Casting Contact
Cooling (When Chlorine Demag-
ging Wet Air Pollution Control
is Practiced On-Site)
Stationary Casting Contact
Cooling
Shot Casting Contact Cooling
BAT Normalized
Discharge Rate
1/kkg gal/ton
0
0
10,868
697
80
1 , 329
43
0
0
2, 607
167
19
319
10
0
0
Production
Normalizing Parameter
kkg of aluminum scrap dried
kkg of aluminum scrap
screened and milled
kkg of dross washed
kkg of aluminum demagged
kkg of aluminum delacquered
kkg of aluminum cast
kkg of aluminum cast
kkg of aluminum cast
kkg of aluminum cast
kkg of aluminum cast
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SECONDARY ALUMINUM SUBCATEGORY SECT - X
TABLE X-4
BAT EFFLUENT LIMITATIONS FOR THE
SECONDARY ALUMINUM SUBCATEGORY
Scrap Drying Wet Air Pollution Control
Pollutant or Maximum for Maximum for
Pollutant property any one day monthly average
Metric Units - mg/kg of aluminum scrap dried
English Units - lbs/million lbs of aluminum scrap dried
Cadmium 0.000 0.000
*Lead 0.000 0.000
*Zinc 0.000 0.000
~Aluminum 0.000 0.000
~Ammonia (as N) 0.000 0.000
~Regulated Pollutant
Scrap Screening and Milling
Pollutant or Maximum for Maximum for
Pollutant property any one day monthly average
Metric Units - mg/kg of aluminum scrap screened and milled
English Units-lbs/million lbs of aluminum scrap screened and milled
Cadmium 0.000 0.000
~Lead 0.000 0.000
~Zinc 0.000 0.000
~Aluminum 0.000 0.000
~Ammonia (as N) 0.000 0.000
~Regulated Pollutant
990
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - X
TABLE X-4 (Continued)
BAT EFFLUENT LIMITATIONS FOR THE
SECONDARY ALUMINUM SUBCATEGORY
Dross Washing
Pollutant or Maximum for Maximum for
Pollutant property any one day monthly average
Metric Units - mg/kg of aluminum dross washed
English Units - lbs/million lbs of aluminum dross washed
Cadmium 2.174 0.869
*Lead 3.043 1.413
~Zinc 11.090 4.565
~Aluminum 66.400 29.450
*Ammonia (as N) 1449.000 636.900
~Regulated Pollutant
Demagging Wet Air Pollution Control
Pollutant or Maximum for Maximum for
Pollutant property any one day monthly average
Metric Units - mg/kg of aluminum scrap demagged
English Units - lbs/million lbs of aluminum scrap demagged
Cadmium
0.139
0.056
~Lead
0.195
0.091
~Zinc
0.711
0. 293
~Aluminum
4. 250
1.889
~Ammonia (as N)
92.910
40.850
~Regulated Pollutant
991
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - X
TABLE X-4 (Continued)
BAT EFFLUENT LIMITATIONS FOR THE
SECONDARY ALUMINUM SUBCATEGORY
Delacquerinq Wet Air Pollution Control
Pollutant or Maximum for Maximum for
Pollutant property any one day monthly average
Metric Units - mg/kg of aluminum delacquered
English Units - lbs/million lbs of aluminum delacquered
Cadmium 0.016 0.006
~Lead 0.022 0.010
~Zinc 0.082 0.034
~Aluminum 0.489 0.217
~Ammonia (as N) 10.670 4.688
*Total Phenols(4-AAP) ~* 0.001
~Regulated Pollutant
**At the source
Direct Chi 11 Casting Contact Cooling
Pollutant or Maximum for Maximum for
Pollutant property any one day monthly average
Metric Units - mg/kg of aluminum cast
English Units - lbs/million lbs of aluminum cast
Cadmium 0.266 0.106
~Lead 0.372 0.173
~Zinc 1.356 0.558
~Aluminum 8.120 3.602
~Ammonia (as N) 177.200 77.880
~Regulated Pollutant
992
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - X
TABLE X-4 (Continued)
BAT EFFLUENT LIMITATIONS FOR THE
SECONDARY ALUMINUM SUBCATEGORY
Ingot Conveyer Casting Contact Cooling (When Chlorine Demagging
Wet Air Pollution Control is Not Practiced On-sTte)
Pollutant or Maximum for Maximum for
Pollutant property any one day monthly average
Metric Units - mg/kg of aluminum cast
English Units - lbs/million lbs of aluminum cast
Cadmium
*Lead
*Zinc
~Aluminum
*Ammonia (as N)
~Regulated Pollutant
0.
0,
0.
0,
5,
009
012
044
263
732
003
006
,018
,117
,520
Ingot Conveyor Casting Contact Cooling (When Chlorine Demagging
Wet Air Pollution Control is Practiced On-Site)
Pollutant or Maximum for Maximum for
Pollutant property any one day monthly average
Metric Units - mg/kg of aluminum screened & milled
English Units - lbs/million lbs of aluminum screened & milled
Cadmium
0. 000
0.000
*Lead
0. 000
0.000
*Zinc
0.000
0.000
~Aluminum
0.000
0 .000
*Ammonia (as N)
0. 000
0.000
~Regulated Pollutant
993
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - X
TABLE X-4 (Continued)
BAT EFFLUENT LIMITATIONS FOR THE
SECONDARY ALUMINUM SUBCATEGORY
Stationary Casting Contact Cooling
Pollutant or
Pollutant property _
Metric Units
English Units
Cadmium
*Lead
*Zinc
*Aluminum
~Anunonia (as N)
~Regulated Pollutant
Maximum for Maximum for
any one day monthly average
mg/kg of aluminum cast
lbs/million lbs of aluminum cast
0,
0,
0,
0,
0,
000
000
000
000
000
0.000
0 .000
0.000
0.000
0.000
Shot Casting Contact Cooling
Pollutant or
Pollutant property
Maximum
any one
for
day
Maximum for
monthly average
Metric Units - mg/kg of aluminum cast
English Units - lbs/million lbs of aluminum cast
Cadmium
*Lead
*Z inc
~Aluminum
~Ammonia (as N)
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0 .000
~Regulated Pollutant
994
-------
io ammonia nccovEnv
vo
VD
Ln
Drosn Washing Wastewater
AMMONIA
SltAM
ginrrwa
9VEAM
D*IncquerIng Scruhhrr Liquor
Carbon to
Rpp.ener.it lor
or Disposal
Art lulled
Cnrhon
Adsorpt Ion
DemaRRlnR
Scrubber
Dcmngglng Scrubber Liquor
?n*ot
Conveyor
Cast Ing
Ingot Conveyor Casting Contact Cooling Water.
Direct Chill Casting Contact Cooling Water
Recycle
\ CoolInR
\ Tower
Chrmlc a I Add 11 Ion
Fqna1!
?atIon
I^VtV
f ,A^A.^X A A
Oil
S|»(mining
ChemlcoI
Precipitation
rJ.~y
*7
Dlscharee
SedlmentatIon
Removal of
Oil And
Crease
Shot Casting Contact C<
t Cooling Water A Cooling /
Tower J J
Recycle <4 1
Sludge
Sludge Recycle
Sludge to
Disposal
Vacuum Filtrate
SludRe Dew,Her Ing
imhiwbm
Recyc
Stationary Canting Contact Cooling Water _ Complete Evaporation
—* - ¦ 1 w
Recycle
Scrap Drying Scrubber Liquor
V
Holding
Tank
Scrap Screening and Milling ^
Mote: Innot Convovor Casting H,iflrew.iter Is
inn? rented In tlie* nom.iRdlnR SrruKher
If rhlnrlnr Dem.ip.p.Inp. Is pr.irMced "n
site.
l Slmlftr
If)
W
O
O
55
a
>
~<
>
f
c
3
H
tz
c:
3
m
C
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w
Q
o
w
~<
V)
w
0
1-3
1
X
Figure X-1
BAT TREATMENT SCHEME OPTION A
SECONDARY ALUMINUM SUBCATEGORY
-------
IO AMMONIA neCOVERV
nronft Washing Wantewnter
Delacquorlng Scrubber Liquor
"emjigglng
Scrubber
Ingot
Conveyor
CastIng
Carbon to
RcgeneratIon
or Disposal
Demagglng Scruhber Liquor
Act Ivated
Carbon
Ad^orpt lott
81EAM
Backwash
Inp.ot Conveyor Casting Contact Cooling Water
Direct Chill Casting Contact Cooling Water
\ Cooling /
\ Tower /
Recycle
Chemical Addition
Equal 1-
?.at Ion
Tank
i',a/aX«:a
on
Skimming
Removal of
Oil and
Crease
Cbemlcii 1
PrecIpltatIon
1*3
Sedlment.it Ion
Sludge
Sludge Recycle
Vacuum filtrate
Hu1tinedIn
Flit rat Ion
Backwash
Sludge to
D1 sposaI
Shot Casting Contact Cooling Water
Coo 1Ing
Tower i
Recycle
M'Mrir:;
Sludge Devaterlng
Stationary Casting Contact Cooling Water Complete Evaporation
Recycle
Note: Ingot Conveyor Casting Wastewater Is
100Z reused in the Pcmagglng Scrubber
(f Chlorine Pemaggittg 1* practiced on
site.
Scrap Drying Scrubber Liquor
Scrap Screening and Hilling
HoidIng
Tank
J
Sludge Removal
Figure X-2
BAT TREATMENT SCHEME OPTION C
SECONDARY ALUMINUM SUBCATEGORY
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - XI
SECTION XI
NEW SOURCE PERFORMANCE STANDARDS
The basis for new source performance standards (NSPS) under
Section 306 of the Act is the best available demonstrated
technology (BDT). New plants have the opportunity to design the
best and most efficient production processes and wastewater
treatment technologies, without facing the added costs and
restrictions encountered in retrofitting an existing plant.
Therefore, Congress directed EPA to consider the best
demonstrated process changes, in-plant controls, and end-of-pipe
treatment technologies which reduce pollution to the maximum
extent feasible.
This section describes the control technology for treatment of
wastewater from new sources and presents mass discharge
limitations of regulatory pollutants for NSPS in the secondary
aluminum subcategory, based on the described control technology.
TECHNICAL APPROACH TO BDT
All of the treatment technology options applicable to a new
source were previously considered for the BAT options. For this
reason, two options were considered for BDT, all identical to the
BAT options discussed in Section X. The treatment technologies
used for the two BDT options are:
OPTION A
o
o
o
o
OPTION C
o
o
o
o
o
997
Preliminary treatment with oil skimming (where required)
Preliminary treatment of delacquering wet air pollution
control wastewater with activated carbon adsorption
In-process flow reduction of casting contact cooling
water and scrubber liquor resulting from scrap drying and
delacquering wet air pollution control
Chemical precipitation and sedimentation
Preliminary treatment with oil skimming (where required)
Preliminary treatment of delacquering wet air pollution
control wastewater with activated carbon adsorption •
In-process flow reduction of casting contact cooling
water and scrubber liquor resulting from scrap drying and
delacquering wet air pollution control
Chemical precipitation and sedimentation
Multimedia filtration
-------
SECONDARY ALUMINUM SUBCATEGORY
SECT - XI
Partial or complete reuse and recycle of wastewater is an
essential part of each option. Reuse and recycle can precede or
follow end-of-pipe treatment. A more detailed discussion of
these treatment options is presented in Section X.
BDT OPTION SELECTION
EPA promulgated the best available demonstrated technology for
the secondary aluminum subcategory on April 8, 1974 as Subpart C
of 40 CFR Part 421. The promulgated NSPS prohibits the discharge
of process wastewater except for an allowance, if determined to
be necessary, which allows the discharge of process wastewater
from chlorine demagging. In this respect, promulgated NSPS was
less stringent than promulgated BAT. The Agency did this
recognizing that NSPS became effective on the date of
promulgation and did not believe that the dry chlorine demagging
processes were immediately available. The Agency believed that
they were appropriate for BAT with its compliance date being 10
years later.
In February of 1983, EPA proposed to modify the promulgated NSPS
to allow for a discharge from chlorine demagging and direct chill
casting. The technology basis was identical to that of the
proposed BAT treatment consisting of in-process flow reduction,
preliminary treatment by oil skimming and ammonia steam
stripping, lime precipitation, sedimentation, and filtration
(Option C).
With the exception of dross washing, the modified NSPS
promulgated for the secondary aluminum subcategory is equivalent
to the BAT technology. Dross washing is not provided a discharge
allowance in the NSPS due to the demonstration of dry milling in
the subcategory. In the 1974 development document for secondary
aluminum, it is stated that 17 of the 23 plants processing
residues (drosses) practice dry milling to eliminate wastewater.
Impact mills, grinders, and screening operations are used to
remove the metallic aluminum values from the nonmetallic values.
Dry milling is not required for existing sources due to the
extensive retrofits of installing mills, grinders, and screening
operations. New sources, however, have the ability to install
the best equipment without the costs of major retrofits.
Therefore, dry milling is considered appropriate for new sources.
For the remaining waste streams, the Agency believes that BAT, as
promulgated, is the best demonstrated technology. Additional
flow reduction and more stringent treatment technologies are not
demonstrated or readily transferable to the secondary aluminum
subcategory.
REGULATED POLLUTANT PARAMETERS
The Agency has no reason to believe that the pollutants that will
be found in treatable concentrations in processes within new
sources will be any different than with existing sources.
Accordingly, pollutants and pollutant parameters selected for
limitation under NSPS, in accordance with the rationale of
998
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - XI
Sections VI and X, are identical to those selected for BAT. The
conventional pollutant parameters TSS, oil and grease, and pH are
also selected for limitation.
NEW SOURCE PERFORMANCE STANDARDS
The NSPS discharge flows for each wastewater source are the same
as the discharge rates for all the BAT options and are presented
in Table XI-1 (page 1000). The mass of pollutant allowed to be
discharged per mass of product is calculated by multiplying the
appropriate achievable treatment concentration by the production
normalized wastewater discharge flows (1/kkg). New source
performance standards for the secondary aluminum subcategory
waste streams are presented in Table XI-2 (page 1001).
999
-------
Table XI-1
NSPS WASTEWATER DISCHARGE RATES FOR THE SECONDARY ALUMINUM SUBCATEGORY
o
o
o
Waste Stream
Scrap Drying Wet Air Pollution
Control
Scrap Screening and Milling
Dross Washing
Demagging Wet Air Pollution
Control
Delacquering Wet Air Pollution
Control
Direct Chill Casting Contact
Cooling
Ingot Conveyor Casting Contact
Cooling (When Chlorine
Demagging Wet Air Pollution
Control is Not Practiced
On-S i te)
Ingot Conveyor Casting Contact
Cooling (When Chlorine
Demagging Wet Air Pollution
Control is Practiced On-Site)
Stationary Casting Contact
Cooling
NSPS Normalized
Discharge Rate
1/kkg gal/ton
0 0
0
0
697
80
1 ,329
43
0
0
167
19
319.
10
Production
Normalizing Parameter
kkg of aluminum scrap dried
kkg of aluminum scrap
screened and milled
kkg of dross washed
kkg of aluminum demagged
kkg of aluminum delacquered
kkg of aluminum cast
kkg of aluminum cast
kkg of aluminum cast
kkg of aluminum cast
Crt
w
n
O
25
O
S
>
f1
C
3
in
G
ca
n
>
t-3
M
O
O
W
~<
w
M
n
X
Shot Casting Contact Cooling
kkg of aluminum cast
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - XI
TABLE XI-2
NSPS FOR THE SECONDARY ALUMINUM SUBCATEGORY
Scrap Drying Wet Air Pollution Control
Pollutant or Maximum for Maximum for
Pollutant property any one day monthly average
Metric Units - mg/kg of aluminum scrap dried
English Units - lbs/million lbs of aluminum scrap dried
Cadmium
~Lead
~Zinc
~Aluminum
~Ammonia (as N)
~Oil and Grease
~TSS
~pH
~Regulated Pollutant
0.000 0.000
0.000 0.000
0.000 0.000
0.000 0.000
0.000 0.000
0.000 0.000
0.000 0.000
Within the range of 7.0 to 10.0
at all times
Scrap Screening and Milling
Pollutant or Maximum for Maximum for
Pollutant property any one day monthly average
Metric Units - mg/kg of aluminum screened and milled
English Units - lbs/million lbs of aluminum screened and milled
Cadmium
0.000
0.000
~Lead
0.000
0.000
~Zinc
0.000
0.000
~Aluminum
0.000
0.000
~Ammonia (as N)
0.000
0.000
~Oil and Grease
0.000
0.000
~TSS
0.000
0.000
~pH
Within the range
at all
of 7.0
times
to 10.0
~Regulated Pollutant
1001
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - XI
TABLE XI-2 Continued)
NSPS FOR THE SECONDARY ALUMINUM SUBCATEGORY
Dross Washing
Pollutant or Maximum for Maximum for
Pollutant property any one day monthly average
|jnits _ mg/kg of aluminum dross washed
English Units - lbs/million lbs of aluminum dross washed
Cadmium
~Lead
~Zinc
~Aluminum
*Ammonia (as N)
~Oil and Grease
~TSS
~pH
~Regulated Pollutant
0.000
0.000
0.000
0 . 000
0.000
0.000
0 . 000
Within the range of 7.0
at all times
,000
.000
.000
,000
.000
0.000
0.000
to 10.0
0
0
0
0
0
Demagging Wet Air Pollution Control
Pollutant or
Maximum for
Maximum for
Pollutant property any one day monthly average
Metric Units - mg/kg of aluminum demagged
English Units - lbs/million lbs of aluminum demagged
Cadmium
~Lead
~Zinc
~Aluminum
~Ammonia (as N)
*Oil and Grease
*TSS
*pH
~Regulated Pollutant
0.139 0.056
0.195 0.091
0.711 0.293
4.250 1.669
92.910 40.850
6.970 6.970
10.460 6.364
Within the range of 7.0 to 10.0
at all times
1002
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - XI
TABLE XI-2 Continued)
NSPS FOR THE SECONDARY ALUMINUM SUBCATEGORY
Delacquering Wet Air Pollution Control
Pollutant or Maximum for Maximum for
Pollutant property any one day monthly average
Metric Units - mg/kg of aluminum delacquered
English Units - lbs/million lbs of aluminum delacquered
Cadmium
0.016
0.006
*Lead
0.022
0.010
*Zinc
0.082
0.034
~Aluminum
0.489
0.217
~Ammonia (as N)
10.670
4.688
~Total Phenols(4-AAP)
0.001
~Oil and Grease
0.800
0.800
~TSS
1.200
0.960
~pH
Within the range of 7.0 to 10.0
at all time
~Regulated Pollutant
~~At the source
Pirect Chill Casting Contact Cooling
Pollutant
Pollutant
or
property
Maximum
any one
for
day
Metric Units - mg/kg of aluminum cast
English Units - lbs/million lbs of aluminum cast
Maximum for
monthly average
Cadmium
~Lead
~Zinc
~Aluminum
~Ammonia (as N)
~Oil and Grease
~TSS
*pH
~Regulated Pollutant
0,
0,
1,
266
372
356
8.120
177.200
13.290
19.940
Within the range of 7.(
at all times
0
0
0,
3,
106
173
558
602
77.880
13.290
15.950
to 10.0
1003
-------
SECONDARY ALUMINUM SUBCATEGORY
SECT - XI
TABLE XI-2 Continued)
NSPS FOR THE SECONDARY ALUMINUM SUBCATEGORY
Ingot Conveyer Castinq Contact Cooling (When Chlorine
Demagging Wet Air Pollution Control is Not Practiced On-Site)
Pollutant or
Pollutant property
Maximum for
any one day
Metric Units - mg/kg of aluminum cast
English Units - lbs/million lbs of aluminum cast
Maximum for
monthly average
Cadmium
~Lead
~Zinc
~Aluminum
~Ammonia (as N)
~Oil and Grease
*TSS
*pH
~Regulated Pollutant
0.009 0.003
0.012 0.006
0.044 0.018
0.263 0.117
5.732 2.520
0.430 0.430
0.645 0.516
Within the range of 7.0 to 10.0
at all times
Ingot Conveyer Casting Contact Cooling (When Chlorine
Demaqging Wet Air Pollution Control is Practiced On-Site)
Pollutant or Maximum for Maximum for
Pollutant property any one day monthly average
Metric Units - mg/kg of aluminum cast
English Units - lbs/million lbs of aluminum cast
Cadmium
0.000
0.000
*Lead
0.000
0.000
~Zinc
0.000
0 . 000
~Aluminum
0.000
0.000
~Ammonia (as N)
0.000
0.000
~Oil and Grease
0.000
0.000
~TSS
0.000
0.000
~pH
Within the range
at all
of 7.0
times
to 10.0
~Regulated Pollutant
1004
-------
SECONDARY ALUMINUM SUBCATEGORY
SECT - XI
TABLE XI-2 Continued)
NSPS FOR THE SECONDARY ALUMINUM SUBCATEGORY
Stationary Casting Contact Cooling
Pollutant or Maximum for Maximum for
Pollutant property any one day monthly average
Metric Units - mg/kg of aluminum cast
English Units - lbs/million lbs of aluminum cast
Cadmium
*Lead
*Zinc
~Aluminum
~Ammonia (as N)
~Oil and Grease
~TSS
~pH
•Regulated Pollutant
0.000 0.000
0.000 0.000
0.000 0.000
0.000 0.000
0.000 0.000
0.000 0.000
0.000 0.000
Within the range of 7.0 to 10.0
at all times
Shot Casting Contact Cooling
Pollutant or Maximum for Maximum for
Pollutant property any one day monthly average
Metric Units - mg/kg of aluminum cast
English Units - lbs/million lbs of aluminum cast
Cadmium
0. 000
0.000
~Lead
0.000
0.000
~Zinc
0.000
0 . 000
•Aluminum
0.000
0.000
•Ammonia (?.s N)
0.000
0.000
~Oil and Grease
0.000
0.000
~TSS
0.000
0 .000
~pH
Within the range
at all
of 7.0
times
to 10.0
~Regulated Pollutant
1005
-------
fo ok
-------
SECONDARY ALUMINUM SUBCATEGORY SECT -XII
SECTION XII
PRETREATMENT STANDARDS
Section 307(b) of the Act requires EPA to promulgate pretreatment
standards for existing sources (PSES), which must be achieved
within three years of promulgation. PSES are designed to prevent
the discharge of pollutants which pass through, interfere with,
or are otherwise incompatible with the operation of publicly
owned treatment works (POTW). The Clean Water Act of 1977
requires pretreatment for pollutants, such as heavy metals, that
limit POTW sludge management alternatives. The existing PSES,
promulgated in 1974, is based on oil skimming, pH adjustment, and
ammonia air stripping technology.
Section 307(c) of the Act requires EPA to promulgate pretreatment
standards for new sources (PSNS) at the same time that it
promulgates- NSPS. New indirect discharge facilities, like new
direct discharge facilities, have the opportunity to incorporate
the best available demonstrated technologies, including process
changes, in-plant controls, and end-of-pipe treatment
technologies, and to use plant site selection to ensure adequate
treatment system installation. The existing PSNS is based on
lime precipitation and sedimentation with in-process flow
reduction.
Pretreatment standards for existing and new sources are to be
technology based and analogous to the best available technology
and the best demonstrated technology, respectively, for removal
of toxic pollutants. For this reason, EPA is modifying the
existing PSES and PSNS.
This section describes the control technology for pretreatment of
process wastewaters from existing sources and new sources in the
secondary aluminum subcategory. Pretreatment standards for
regulated pollutants are presented based on the described control
technology.
TECHNICAL APPROACH TO PRETREATMENT
Before promulgating pretreatment standards, the Agency examines
whether the pollutants discharged by the subcategory pass through
the POTW or interfere with the POTW operation or its chosen
sludge disposal practices. In determining whether pollutants
pass through a well-operated POTW, achieving secondary treatment,
the Agency compares the percentage of a pollutant removed by POTW
with the percentage removed by direct dischargers applying the
best available technology economically achievable. A pollutant
is deemed to pass through the POTW when the average percentage
removed nationwide by well-operated POTW meeting secondary
treatment requirements is less than the percentage removed by
direct dischargers complying with BAT effluent limitations
guidelines for that pollutant. (see generally, 46 FR at 9415-16,
1007
-------
SECONDARY ALUMINUM SUBCATEGORY SECT -XII
January 20, 1981).
This definition of pass through satisfies two competing
objectives set by Congress: (1) that standards for indirect
dischargers be equivalent to standards for direct dischargers,
while at the same time, (2) that the treatment capability and
performance of the POTW be recognized and taken into account in
regulating the discharge of pollutants from indirect dischargers.
The Agency compares percentage removal rather than the mass or
concentration of pollutants discharged because the latter would
not take into account the mass of pollutants discharged to the
POTW from non-industrial sources nor the dilution of the
pollutants in the POTW effluent to lower concentrations due to
the addition of large amounts of non-industrial wastewater.
PRETREATMENT STANDARDS FOR EXISTING AND NEW SOURCES
Options for pretreatment of wastewaters from both existing and
new sources are based on increasing the effectiveness of end-of-
pipe treatment technologies. All in-plant changes and applicable
end-of-pipe treatment processes have been discussed previously in
Sections X and XI. The options for PSNS and PSES, therefore, are
the same as the BAT options discussed in Section X. Although oil
and grease is a conventional pollutant compatible with treatment
provided by POTW, oil skimming is needed for the PSNS treatment
technology to ensure proper removal. Oil and grease interferes
with the chemical addition and mixing required for chemical
precipitation and treatment.
A description of each option is presented in Section X.
Treatment technology options for the PSES and PSNS are:
OPTION A
o Preliminary treatment with oil skimming (where required)
o Preliminary treatment of dross washing wastewater with
ammonia steam stripping
o Preliminary treatment of delacquering wet air pollution
control wastewater with activated carbon adsorption
o In-process flow reduction of casting contact cooling
water and scrubber liquor resulting from scrap drying and
delacquering wet air pollution control
o Chemical precipitation and sedimentation
OPTION C
o Preliminary treatment with oil skimming (where required)
o Preliminary treatment of dross washing wastewater with
ammonia steam stripping
o Preliminary treatment of delacquering wet air pollution
control wastewater with activated carbon
o In-process flow reduction of casting contact cooling
water and scrubber liquor resulting from scrap drying and
delacquering wet air pollution control
o Chemical precipitation and sedimentation
1008
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SECONDARY ALUMINUM SUBCATEGORY SECT -XII
o Multimedia filtration
INDUSTRY COST AND POLLUTANT REMOVAL ESTIMATES
The industry cost and environmental benefits of each treatment
option were used to determine the most cost-effective option. The
methodology applied in calculating pollutant removal estimates
and plant compliance costs is discussed in Section X.
Table XII-1 (page 1011) shows the estimated pollutant removal
estimates for indirect dischargers. Compliance costs are
presented in Table VIII-2, (page 971).
PSES AND PSNS OPTION SELECTION
The technology basis for the promulgated PSES and PSNS is
identical to BAT (Option C) and NSPS, respectively. The
treatment scheme consists of in-process flow reduction,
preliminary treatment with ammonia steam stripping, activated
carbon adsorption, and oil skimming (where required), followed by
lime precipitation, sedimentation, and filtration. EPA knows of
no demonstrated technology that provides more efficient pollutant
removal than BAT technology. No additional flow reduction for
new sources is feasible because the only other available flow
reduction technology, reverse osmosis (Option F) is not
adequately demonstrated nor is it clearly transferable for this
subcategory. Just as in the BAT effluent limitations, at-the-
source monitoring and compliance is required for total phenolics
in delacquering wet air pollution control wastewater.
The selected option for PSES increases the removal of
approximately 11,300 kg/yr of toxic metals and 210 kg/yr of total
phenolics over the estimated raw discharge. Estimated removal
over the intermediate option considered is 11.6 kg/yr of toxic
metals. The estimated capital cost of PSES is $2.3 million (1982
dollars) and the annual cost is §1.4 million (1982 dollars).
REGULATED POLLUTANT PARAMETERS
Pollutants selected for regulation under PSES and PSNS are
identical to those selected for regulation for BAT. The
conventional pollutants oil and grease, TSS, and pH are not
limited under PSES and PSNS because they are effectively
controlled by POTW. PSES and PSNS prevent the pass-through of
lead, zinc, ammonia, and total phenols. The toxic pollutants are
removed by well-operated POTW on an average of 53 percent (lead -
49 percent, zinc - 65 percent, phenol - 96 percent, and ammonia -
0 percent). Aluminum is not limited because in its hydroxide form
it is used by POTW as a flocculant aid in the settling and
removal of suspended solids. As such, aluminum in limited
quantities does not pass through or interfere with POTW; rather
it is a necessary aid to its operation.
1009
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SECONDARY ALUMINUM SUBCATEGORY SECT -XII
PRETREATMENT STANDARDS
In proposing PSES and PSNS, the Agency considered whether to
propose exclusively mass-based standards, or to allow a POTW the
alternative of concentration or mass-based standards. Mass-based
standards ensure that limitations are achieved by means of
pollutant removal rather than by dilution. They are particularly
important when a limitation is based upon flow reduction because
pollutant limitations associated with the flow reduction cannot
be measured any way but as a reduction of mass discharged. Mass-
based standards, however, are harder to implement because a POTW
faces increased difficulties in monitoring. A POTW also must
develop specific limits for each plant based on the unit
operations present and the production occurring in each
operation.
EPA resolved these competing considerations by proposing mass-
based standards exclusively where the PSES and PSNS treatment
options include significant flow reductions or where significant
pollutant removals are attributable to flow reductions. Flow
reduction over current discharge rates was minimal (0.2 percent)
in the secondary aluminum subcategory in the proposed standards.
For secondary aluminum, EPA concluded that the proposed PSES
should provide alternative mass-based and concentration-based
standards.
The addition of ingot conveyer casting, however, now requires
substantial flow reduction for the secondary aluminum
subcategory. Recycle of ingot conveyer casting is based on 90
percent recycle when demagging scrubbers are not used and 100
percent reuse in demagging air pollution control when scrubbers
are used. It is now estimated the PSES technology will reduce
current flows by 25 percent. Consequently, concentration-based
standards are not promulgated for this subcategory to ensure that
flow reduction is achieved.
The PSES discharge flows are identical to the BAT discharge flows
for all processes. These discharge flows are listed in Table
XII-2, (page 1012) As shown in Table XII-3 (page 1014), the PSNS
discharge flows are identical to the NSPS flows. The mass of
pollutant allowed to be discharged per mass of product is
calculated by multiplying the achievable treatment concentration
(mg/1) by the normalized wastewater discharge flow (1/kkg). PSES
and PSNS are shown in Tables XII-4 and XII-5, (pages 1016 and
1020) respectively.
1010
-------
Table XII-1
POLLUTANT REMOVAL
ESTIMATES
FOR THE SECONDARY
ALUMINUM
INDIRECT DISCHARGERS
TOTAL
OPTION A
OPTION A
OPTION C
OPTION C
RAW WASTE
DISCHARGED
REMOVED
DISCHARGED
REMOVED
POLLUTANT
(kg/yr)
(kg/yr)
(kg/yr)
(kg/yr)
(kg/yr)
Cadmium
9. 920. 4
5.4
9,915.0
3.4
9,917.0
Lead
542.5
8.2
534.3
5. 5
537. 1
Zinc
827. 7
22.6
805. 1
15.8
811.9
TOTAL TOXIC METALS
11,290.6
36. 2
11.254.4
24.6
11,266.0
Phenollcs (4-AAP)
212. 5
0. 7
211.8
0. 7
211.8
Alumlnum
129.548.2
153.4
129,394.8
102.0
129.446.1
Ammonia
2,286.9
2,191.4
95.5
2,191.4
95. 5
TOTAL NONCONVENTIONALS
132,047.5
2,345.4
129,702.1
2.294.1
129.753.4
TSS
487.443.5
821.8
486,621.7
178.0
487,265.4
011 ft Grease
22,854.4
684. 8
22,169.6
684. 8
22,169.6
TOTAL CONVENTIONALS
510.297.8
1,506.6
508.791.3
862.8
509.435.0
TOTAL POLLUTANTS
653.635.9
3,888.2
649.747.7
3. 181. 5
650.454.4
FLOW (l/yr)
68,480.000
68,480,000
NOTE: TOTAL TOXIC METALS - Cadmlun + Lead + Zinc
TOTAL NONCONVENTIONALS - Aluminum + Ammonia + Phenolles
TOTAL CONVENTIONALS - TSS ~ 011 4 Grease
TOTAL POLLUTANTS - Total Toxic Metals + Total NonconventlonaIs + Total ConventlonaIs
OPTION A - Oil Skimming, Ammonia Steam Stripping, Activated Carbon Adsorption, In-process Flow Reduction,
and Lime Precipitation and Sedimentation
OPTION C - Option A, plus Multimedia Filtration
-------
Table XII-2
PSES WASTEWATER DISCHARGE RATES FOR THE SECONDARY ALUMINUM SUBCATEGORY
o
i-*
N)
Waste Stream
Scrap Drying Wet Air Pollution
Control
Scrap Screening and Milling
Dross Washing
Uemagging Wet Air Pollution
Control
Delacquering Wet Air Pollution
Control
Direct Chill Casting Contact
Coo ling
Ingot Conveyor Casting Contact
Cooling (When Chlorine
Demagginj> Wet Air Pollution
Control is Not Practiced
On-Site)
Ingot Conveyor Casting Contact
Cooling (When Chlorine
Demagging Wet Air Pollution
Control is Practiced On-Site)
PSES
Normalized
Discharge Rate
1/kkg gal/ton
0
0
10,868
697
80
1 ,329
43
0
0
2,607
167
19
319
10
Product ion
Normalizing Parameter
kkg of aluminum scrap dried
kkg of aluminum scrap
screened and milled
kkg of dross washed
kkg of aluminum demagged
kkg of aluminum delacquered
kkg of aluminum cast
kkg of aluminum cast
kkg of aluminum cast
l/l
m
o
O
Z
a
%
>
tr1
i/i
G
(0
n
>
m
o
o
w
~c
i/i
m
n
x
-------
Table XII-2 (Continued)
PSES WASTEWATER DISCHARGE RATES FOR THE SECONDARY ALUMINUM SUBCATEGORY
Waste Stream
Stationary Casting Contact
Coo ling
PSES
Normalized
Discharge Rate
1/kkg Ral/ton
0 0
Product ion
Normalizing Parameter
kkg of aluminum cast
Shot Casting Contact Cooling
0
kkg of aluminum cast
-------
Table XII-3
PSNS WASTEWATER DISCHARGE RATES FOR THE SECONDARY ALUMINUM SUBCATEGORY
o
i-»
Waste Stream
Scrap Drying Wet Air Pollution
Control
Scrap Screening and Milling
Dross Washing
Demagging Wet Air Pollution
Control
Delacquering Wet Air Pollution
Control
Direct Chill Casting Contact
Cooling
Ingot Conveyor Casting Contact
Cooling (When Chlorine
Demaggin§ Wet Air Pollution
Control is Not Practiced
On-Site)
Ingot Conveyor Casting Contact
Cooling (When Chlorine
Demagging Wet Air Pollution
Control is Practiced On-Site)
PSNS
Normalized
Discharge Rate
1/kkg gal/ton
0
0
0
697
80
1 ,329
43
0
0
0
0
167
19
319
10
Product ion
Normalizing Parameter
kkg of aluminum scrap dried
kkg of aluminum scrap
screened and milled
kkg of dross washed
kkg of aluminum demagged
kkg of aluminum delacquered
kkg of aluminum cast
kkg of aluminum cast
kkg of aluminum cast
-------
Table XII-3 (Continued)
PSNS WASTEWATER DISCHARGE RATES FOR THE SECONDARY ALUMINUM SUBCATEGORY
Waste Stream
Stationary Casting Contact
Cooling
PSNS
Normalized
Discharge Rate
1/kkg
gal/ton
0
Product ion
Normalizing Parameter
kkg of aluminum cast
Shot Casting Contact Cooling
kkg of aluminum cast
-------
SECONDARY ALUMINUM SUBCATEGORY SECT -XII
TABLE XII-4
PSES FOR THE SECONDARY ALUMINUM SUBCATEGORY
Scrap Drying Wet Air Pollution Control
wm ¦ ¦ ¦ wm mwwwwwwwwwwwwwwwmmwm ———— mmmmmmmmmmmmmmmmmmmmmmmmm ^^^^^^^B^wm^m—mmmmmmmmmm
Pollutant or Maximum for Maximum for
Pollutant property any one day monthly average
~ Metric Units - mg/kg of aluminum scrap dried
English Units - lbs/million lbs of aluminum scrap dried
Cadmium 0.000 0.000
*Lead 0.000 0.000
*Zinc 0.000 0.000
*Anmionia (as N) 0.000 0.000
~Regulated Pollutant
Scrap Screening and Milling
Pollutant or Maximum for Maximum for
Pollutant property any one day monthly average
Metric Units - mg/kg of aluminum delacquered
English Units -lbs/million lbs of aluminum scrap screened & milled
Cadmium 0.000 0.000
*Lead 0.000 0.000
*Zinc 0.000 0.000
~Ammonia (as N) 0.000 0.000
~Regulated Pollutant
Dross Washing
Pollutant or Maximum for Maximum for
Pollutant property any one day monthly average
Metric Units - mg/kg of dross washed
English Units - lbs/million lbs of dross washed
Cadmium 2.174 0.869
*Lead 3.043 1.413
*Zinc 11.090 4.565
~Ammonia (as N) 1449.000 636.900
~Regulated Pollutant
1016
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SECONDARY ALUMINUM SUBCATEGORY SECT -XII
TABLE XI1-4 (Continued)
PSES FOR THE SECONDARY ALUMINUM SUBCATEGORY
Demagqing Wet Air Pollution Control
Pollutant or Maximum for Maximum for
Pollutant property any one day monthly average
~ Metric Units - mg/kg of aluminum demagged
English Units - lbs/million lbs of aluminum demagged
Cadmium 0.139 0.056
*Lead 0.195 0.091
*Zinc 0.711 0.293
~Ammonia (as N) 92.910 40.850
*Regulated Pollutant
Delacquering Wet Air Pollution Control
Pollutant or Maximum for Maximum for
Pollutant property any one day monthly average
Metric Units - mg/kg of aluminum delacquered
English Units - lbs/million lbs of aluminum delacquered
Cadmium 0.016 0.006
*Lead 0.022 0.010
*Zinc 0.082 0.034
~Ammonia (as N) 10.670 4.688
*Total Phenols(4-AAP) ~~ 0.001
~Regulated Pollutant
**At the source
Pirect Chill Casting Contact Cooling
Pollutant or Maximum for Maximum for
Pollutant property any one day monthly average
Metric Units - mg/kg of aluminum delacquered
English Units - lbs/million lbs of aluminum delacquered
Cadmium 0.266 0.106
~Lead 0.372 0.173
~Zinc 1.356 0.558
~Ammonia (as N) 177.200 77.880
~Regulated Pollutant
1017
-------
SECONDARY ALUMINUM SUBCATEGORY SECT -XII
TABLE XI1-4 (Continued)
PSES FOR THE SECONDARY ALUMINUM SUBCATEGORY
Ingot Conveyer Casting Contact Cooling (When Chlorine
Demagging Wet Air Pollution Control is Not Practiced On-Site)
Pollutant or Maximum for Maximum for
Pollutant property any one day monthly average
Metric Units - mg/kg of aluminum cast
English Units - lbs/million lbs of aluminum cast
Cadmium 0.009 0.003
~Lead 0.012 0.006
~Zinc 0.044 0.018
~Ammonia (as N) 5.732 2.520
~Regulated Pollutant
Ingot Conveyer Casting Contact Cooling (When Chlorine
Demagging Wet Air Pollution Control is Practiced On-Site)
Pollutant or Maximum for Maximum for
Metric Units
- mg/kg of aluminum
cast
English Units - lbs/million lbs of aluminum
cast
Cadmium
0.000
0 .000
~Lead
0.000
0 .000
~Zinc
0.000
0.000
~Ammonia (as N)
0.000
0.000
~Regulated Pollutant
Stationary Casting Contact
Cooling
Pollutant or.
Maximum for
Maximum for
Pollutant property
any one day
monthly average
Metric. Units
- mg/kg of aluminum
cast
English Units - lbs/million lbs of aluminum
cast
Cadmium
0.000
0.000
~Lead
0.000
0.000
~Zinc
0.000
0.000
~Ammonia (as N)
0.000
0.000
~Regulated Pollutant
1018
-------
SECONDARY ALUMINUM SUBCATEGORY SECT -XII
TABLE XI1-4 (Continued)
PSES FOR THE SECONDARY ALUMINUM SUBCATEGORY
Shot Casting Contact Cooling
Pollutant or Maximum for Maximum for
Pollutant property any one day monthly average
Met~^c units - mg/kg of aluminum cast
English Units - lbs/million lbs of aluminum cast
*
Cadmium 0.000 0.000
*Lead 0.000 0.000
*Zinc 0.000 0.000
*Anunonia (as N) 0.000 0.000
~Regulated Pollutant
1019
-------
SECONDARY ALUMINUM SUBCATEGORY SECT -XII
TABLE XI1-5
PSNS FOR THE SECONDARY ALUMINUM SUBCATEGORY
Scrap Drying Wet Air Pollution Control
Pollutant or Maximum for Maximum for
Pollutant property any one day monthly average
Metric Units - mg/kg of aluminum scrap dried
English Units - lbs/million lbs of aluminum scrap dried
Cadmium 0.000 0.000
*Lead 0.000 0.000
~Zinc 0.000 0.000
*Ammonia (as N) 0.000 0.000
~Regulated Pollutant
Scrap Screening and Milling
Pollutant or Maximum for Maximum for
Pollutant property any one day monthly average
Metric Units - mg/kg of aluminum scrap screened s. milled
English Units-lbs/million lbs of aluminum scrap screened s> milled
Cadmium 0.000 0.000
~Lead 0.000 0.000
~Zinc 0.000 0.000
~Ammonia (as N) 0.000 0.000
~Regulated Pollutant
Dross Washing
Pollutant or Maximum for Maximum for
Pollutant property any one day monthly average
Metric Units - mg/kg of dross washed
English Units - lbs/million lbs of dross washed
Cadmium 0.000 0.000
~Lead 0.000 0.000
~Z inc 0.000 0.000
~Ammonia (as N) 0.000 0.000
~Regulated Pollutant
1020
-------
SECONDARY ALUMINUM SUBCATEGORY SECT -XII
TABLE XI1-5 (Continued)
PSNS FOR THE SECONDARY ALUMINUM SUBCATEGORY
Demagging Wet Air Pollution Control
Pollutant or Maximum for Maximum for
Pollutant property any one day monthly average
Metric Units - mg/kg of aluminum demagged
English Units - lbs/million lbs of aluminum demagged
Cadmium 0.139 0.056
*Lead 0.195 0.091
*Zinc 0.711 0.293
*Ammonia (as N) 92.910 40.850
*Regulated Pollutant
Delacquering Wet Air Pollution Control
Pollutant or Maximum for Maximum for
Pollutant property any one day monthly average
Metric Units - mg/kg of aluminum delacquered
English Units - lbs/million lbs of aluminum delacquered
Cadmium 0.016 0.006
*Lead 0.022 0.010
*Zinc 0.082 0.034
*Ammonia (as N) 10.670 4.688
*Total Phenols(4-AAP) ** 0.001
~Regulated Pollutant
**At the source
Direct Chill Casting Contact Cooling
Pollutant or Maximum for Maximum for
Pollutant property any one day monthly average
Metric Units - mg/kg of aluminum cast
English Units - lbs/million lbs of aluminum cast
Cadmium 0.266 0.106
*Lead 0.372 0.173
*Zinc 1.356 0.588
*Ammonia (as N) 177.200 77.880
^Regulated Pollutant
1021
-------
SECONDARY ALUMINUM SUBCATEGORY SECT -XII
TABLE XII-5 (Continued)
PSNS FOR THE SECONDARY ALUMINUM SUBCATEGORY
Ingot Conveyer Casting Contact Cooling (When Chlorine
Demagging Wet Air Pollution is Not Practiced On-Site)
Pollutant or Maximum for Maximum for
Pollutant property any one day monthly average
Met^c units - mg/kg of aluminum cast
English Units - lbs/million lbs of aluminum cast
Cadmium 0.009 0.003
*Lead 0.012 0.006
~Zinc 0.044 0.018
~Ammonia (as N) 5.732 2.520
~Regulated Pollutant
Ingot Conveyer Casting Contact Cooling (When Chlorine
Demagging Wet Air Pollution Control is Practiced On-Site)
Pollutant or Maximum for Maximum for
Pollutant property any one day monthly average
Metric Units - mg/kg of aluminum cast
English Units - lbs/million lbs of aluminum cast
Cadmium 0.000 0.000
~Lead 0.000 0.000
~Zinc 0.000 0.000
~Ammonia (as N) 0.000 0.000
~Regulated Pollutant
Stationary Casting Contact Cooling
Pollutant or Maximum for Maximum for
Pollutant property any one day monthly average
Met^c units - mg/kg of aluminum cast
English Units - lbs/million lbs of aluminum cast
Cadmium 0.000 0.000
~Lead 0.000 0.000
~Zinc 0.000 0.000
~Ammonia (as N) 0.000 0.000
~Regulated Pollutant
1022
-------
SECONDARY ALUMINUM SUBCATEGORY SECT -XII
TABLE XII-5 (Continued)
PSNS FOR THE SECONDARY ALUMINUM SUBCATEGORY
Shot Casting Contact Cooling
Pollutant or Maximum for Maximum for
Pollutant property any one day monthly average
Metric Units - mg/kg of aluminum scrap dried
English Units - lbs/million lbs of aluminum scrap dried
Cadmium 0.000 0.000
*Lead 0.000 0.000
*Zinc 0.000 0.000
*Ammonia (as N) 0.000 0.000
~Regulated Pollutant
1023
-------
SECONDARY ALUMINUM SUBCATEGORY SECT - XIII
SECTION XIII
BEST CONVENTIONAL POLLUTANT CONTROL TECHNOLOGY
EPA is not promulgating best conventional pollutant control
technology (BCT) for the secondary aluminum subcategory at this
time.
1025
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