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In certain cases, another Categorical Pretreatment Standard may also
cover wastewater discharges from metal finishing operations. In these
Situations, the more specific standards will apply to those metal finishing
wastestreams which appear to be covered by both standards. The following
regulations take precedence over the Metal Finishing regulation.
- Nonferrous Smelting and Refining (40 CFR Part 421)
- Coil Coating (40 CFR Part 465)
- Porcelain Enameling (40 CFR Part 466)
- Battery Manufacturing (40 CFR Part 461)
- Iron and Steel Manufacturing (40 CFR Part 420)
- Metal Casting Foundries (40 CFR Part 464)
- Aluminum Forming (40 CFR Part 467)
- Copper Forming (40 CFR Part 468)
- Plastic Molding and Forming (40 CFR Part 463)
- Electrical and Electronic Components (40 CFR Part 469)
- Nonferrous Forming (40 CFR Part 471)
For example, if a plant performs a cleaning and phosphate coating
operation, in preparation for painting and also performs cleaning, pickling,
immersion coating, and chemical coating as part of a porcelain enameling
process, then the Metal Finishing PSES apply to the discharge from the
cleaning and phosphate coating operation, while the Porcelain Enameling PSES
apply to the discharge from application of the porcelain enamel and also the
preparatory operations of cleaning, pickling, immersion plating, and chemical
coating operation. Normally, the metal preparation operations (cleaning,
pickling, immersion plating, and chemical coating) would be subject to the
Metal Finishing regulation. However, because the Porcelain Enameling regula-
tions specifically include those operations performed in preparation for the
.porcelain enameling operation, the Porcelain Enameling regulation takes prece-
dence for those wastestreams (See Figure 3.1).
3.3 PRETREATMENT STANDARDS FOR THE METAL FINISHING CATEGORY
The Metal Finishing Standards (40 CFR Part 433) establish pretreatment
standards for new and existing facilities performing electroplating and other
3-14
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Metal Finishing Process
Metal Finishing
- cleaning
- phosphate coating
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Porcelain Enameling
Metal Preparation
cleaning
pickling
immersion plating
chemical coating
Metal Finishing
- painting
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Porcelain Enameling
- steel coating
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Wastewater to Discharge ----- .-•
These four operations are normally subject to the Metal Finishing regula-
tion; however, in this case, they are performed immediately prior to a
porcelain enameling operation. These types of operations were included
as part of the data base used to develop the Porcelain Enameling regula-
tions, thus, in this situation, they are subject to the Porcelain
Enameling regulation.
Wastestream
is subject to Part 433 if discharged. Wastestream
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FIGURE 3.1
SCHEMATIC SHOWING EXAMPLE OF OVERLAP COVERAGE OF CATEGORICAL
STANDARDS AT INTEGRATED FACILITIES
3-15
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metal finishing operations. These standards are BAT-equivalent and represent
the best available technology economically achievable. All existing indirect
discharging electroplating facilities (except job shop electroplaters and
IPCBMs) must first comply with the Electroplating (Part 413) and then with the
Metal Finishing (Part 433) regulations. Another exception is continuous strip
electroplating at Iron and Steel Mills which is subject only to the Metal
Finishing regulation; this unit operation is not subject to the Electroplating
regulation. The limits apply uniformly to discharges from all electroplating
and other metal finishing operations. The uniformity in standards meets
industry requests for equivalent limits for process lines often found to-
gether. The Metal Finishing Standards also reduce the need to use the Com-
bined Wastestream Formula. No production based standards were developed for
the Metal Finishing (Part 433) Regulation. The Metal Finishing standards are
based on the 99th percentile of expected variations from observed long-term
unconstructed averages. They include daily maximums and maximum monthly
(statistically based on 10 samples per month) average concentration limita-
tions. The PSES and PSNS limitations for metal finishing facilities are
presented in Table 3.3. If a plant intends to consistently comply with the
regulatory limit it should use the long term concentration average as the
basis for design and operation. Table 3.4 presents long-term concentration
averages which were found to be attainable by the technology EPA assessed.
They are presented as guidance to dischargers and control authorities.
The pretreatment standards for new sources (PSNS) apply to electroplating
and metal finishing facilities which began their operation after August 31,
1982, the date of the proposed regulation. The PSNS for metal finishing
facilities are the same as those for existing sources, with the exception that
cadmium must be controlled more stringently.
3.4 POLLUTANTS EXCLUDED FROM REGULATION
The EPA excluded from regulation 7 of the 126 toxic pollutants which are
given priority consideration (antimony, arsenic, asbestos, beryllium, mercury,
selenium, and thallium). These pollutants are found in only a small number of
sources and are effectively controlled by the technologies on which the limits
are based.
3-16
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TABLE 3.3
PRETREATMENT STANDARDS FOR THE METAL FINISHING CATEGORY
40 CFR PART 433
PRETREATMENT STANDARDS FOR EXISTING SOURCES (PSES)
Pollutant
Cadimium (T )
Chromium (T)
Copper (T)
.Lead (T)
Nickel (T)
Silver (T)
Zinc (T)
Cyanide, total
Total Toxic Organics (interim)
Total Toxic Organics (final)
Alternative to total cyanide:
Cyanide, amenable to chlorination
Daily
Maximum (mg/1)
0.69
2.77
3.38
0.69
3.98
0.43
2.61
1.20
4.57
2.13
0.86
Maximum Monthly
Average (mg/1)
1 0.26
1.71
2.07
0.43
2.38
0.24
1.48
0.65
0.32
PRETREATMENT STANDARDS FOR NEW SOURCES (PSNS)
Pollutant
Cadmium (T)
Chromium (T)
Copper (T)
Lead (T)
Nickel (T)
Silver (T)
Zinc (T)
Cyanide, total
Total Toxic Organics
Alternative to total cyanide:
Cyanide, amenable to chlorination
Daily
Maximum (mg/1)
0.11
2.77
3.38
0.69
3.98
0.43
2.61
1.20
2.13
0.86
Maximum Monthly
Average (mg/1)
0.07
1.71
2.07
0.43
2.38
0.24
1.48
0.65
0.32
Note:
No maximum monthly average TTO concentration regulated.
(T) = total.
3-17
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TABLE 3.4
LONG TERM CONCENTRATION AVERAGES
Pollutant of Pollutant Property
Long Term
Concentration
Average
Milligrams
Per Liter
(mg/1)
Cadmium (T)
Chromium (T)
Copper (T)
Lead (T)
Nickel (T)
Silver OT)
Zinc (T)
Cyanide (T)
Cyanide, A
TTO (raw water)
TTO (effluent)
0.13
0.572
0.815
0.20
0.942
0.096
0.549
0.18
0.06
1.08
0.434
1
Cadmium (T) for new sources is 0.058 mg/1.
3-H
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3.5 COMPLIANCE DATES
All industries subject to the Electroplating Standards (except job shop
electroplaters and IPCBMs) will have to comply with thef Metal Finishing (Part
433) regulations. The control of toxic organics is an additional requirement
for facilities currently under Electroplating PSES. Compliance was found to
be achievable with good management practices (recovering solvents for contract
hauling or reclamation) and at low costs. An interim TTO limit based solely
on achieving compliance with good housekeeping practices before end-of-pipe
treatment is required to be in-place, and was established to prevent organics
from being completely uncontrolled during the time before final compliance.
The Metal Finishing compliance dates are shown in Table 3.5.
3.6 ALTERNATIVE CYANIDE LIMITATION
An alternative cyanide limit is available for facilities with significant
forms of complexed cyanide (i.e. iron cyanides) not controllable by the tech-
nology basis. These complexed forms are less toxic but may still undergo
transformation to the more toxic free cyanide form in the waterways. Before
allowing the cyanide amenable alternative, the Control Authority should con-
sider possible water quality impacts due to the discharge of cyanide. Complex
cyanides can be controlled by the addition of ferrous sulfate to the precipi-
tation/clarification system.
3-19
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TABLE 3.5
COMPLIANCE DATES FOR METAL FINISHING PRETREATMENT STANDARDS
40 CFR PART 433
Pollutant
Parameter
Interim TTO
Metals, Cyanide,
and Final TTO
Existing Sources
Capitives
June 30, 19842
February 15, 1986
New
Sources
on commencement
of discharge
TTO » Total Toxic Organics
2July 10, 1985 for plants covered by 40 CFR Part 420, Iron and Steel
3-20
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4. TREATMENT TECHNOLOGIES
The treatment technologies described in this section are currently used
by metal finishers/electroplaters to remove or recover wastewater pollutants
normally generated. Figure 4.1 is an example of the current technology com-
monly used for treatment of metal finishing wastewater. As indicated, waste-
stream segregation allows the recovery of precious metals, the reduction of
hexavalent chromium, the destruction of cyanide, and the removal and recovery
of oils prior to the removal of common metals. Wastestream segregation can
reduce the flow of wastewater to the treatment system and, accordingly, reduce
the cost of treatment.
4.1 TREATMENT OF COMMON METALS WASTE
The technology basis for the pretreatment standards consists of hydroxide
precipitation followed by sedimentation. Hydroxide precipitation is used to
precipitate dissolved metals by chemical addition so that they can be removed
by physical means such as sedimentation or filtration. Hexavalent chromium is
not removed by this treatment system and cyanide will interfere with the
system's ability to remove the dissolved metals. These raw waste types should
be treated before entering this system.
The EPA also considered but rejected the addition of filtration to the
selected technology basis to remove additional suspended solids (such as metal
hydroxides) which did not settle out in the clarifier. It may be appropriate
in cases where there are specific ambient water quality problems. The tech-
nology basis treatment system plus in-plant cadmium controls (such as evapora-
tive recovery and ion exchange) was used as the technology .basis for new
source pretreatment standards.
Alternative treatment methods for common metals removal, to be used in
conjunction with or in place of the preceeding methods, include peat adsorp-
tion, insoluble starch xanthate filtration, sulfide precipitation, flotation,
and membrane filtration.
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: 4.2 TREATMENT OF COMPLEXED METAL WASTES
Complexed metals are tied up by chemicals (complexing agents such as
ammonia and citric acid) which prevent the metals from settling out of
solution. Complexed metal wastes are a product of electroless plating,'
immersion plating, etching and printed circuit board manufacturing. Metals "
tied up in solution counteract the conventional precipitation technique. As a
result, .segregated treatment of the'complexed metal wastes is recommended.
High PH precipitation is a process involving the addition of chemicals
which drastically increase the PH to around 12, prompting a shift in the
complex dissociation equilibrium and resulting in the production of free metal
ions. The metal ions can then be precipitated by available hydroxide ions and
removed by sedimentation. • ,, ;
The chemical reduction process adds chemicals to lower the pH of the
wastestream (to break up the various metal complexes) followed by the addition
of a reducing agent, to reduce the metals to an oxidation state which permits
precipitation of the metals. Additional chemicals to raise the, pH are then
added to form metallic precipitates which settle out of solution. Media or
membrane filtration is an alternate method to sedimentation for solids
removal.
Modifying the hydroxide precipitation process by substituting sulfide
precipitation can improve system performance in the removal of complexed heavy
metals. The ferrous sulfate technique is capable of achieving low metal
solubilities in spite of the presence of certain complexing agents.
4.3 TREATMENT OF PRECIOUS METALS WASTES
Treatment of precious metals consists of the technology basis for common
metals wastes plus precious metals recovery including evaporation, ion
exchange, and electrolytic recovery. Evaporation is used to recover precious
metals by boiling off the water portion of the precious metal solution and
removing the metal. '
4-3
-------
Ion exchange is the process in which ions, held by electrostatic forces
to charged functional groups on the surface of an ion exchange resin, are
exchanged for ions of similar charge from the solution in which the resin is
immersed. Ion exchange is commonly used for precious metal recovery,
especially gold.
Electrolytic recovery is particularly applicable to precious metals
recovery because the valuable precious metals offer a faster payback on
equipment and energy costs. The process consists of a dragout rinse after the
plating step and an off line electrolytic recovery tank.
4.4 TREATMENT OF HEXAVALENT CHROMIUM
The treatment of hexavalent chromium involves reducing hexavalent
chromium to trivalent chromium and removal with a conventional precipitation-
solids removal system. Reduced (trivalent) chromium is able to be separated
from solution in conjunction with other metallic salts by alkaline precipita-
tion. In most cases, gaseous sulfur dioxide is used as the reducing agent in
the reduction of hexavalent chromium which enables the trivalent chromium to
be separated from solution by alkaline precipitation.
Alternative hexavalent chromium treatment techniques include
electrochemical chromium reduction, regeneration, evaporation, and ion
exchange.
4.5 TREATMENT OF CYANIDE WASTES
Treatment of cyanide is almost exclusively performed by alkaline
chlorination which focuses upon oxidizing the cyanide which is amenable to
chlorination. The destruction of cyanide results in products of carbon
dioxide and nitrogen. Additionally, ferrous sulfate may be used to precipi-
tate complexed cyanides.
Alternative treatment techniques for the destruction of cyanide include
oxidation by ozone, ozone with ultraviolet radiation, hydrogen peroxide, and
electrolytic oxidation.
4-4
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4.6 TREATMENT OF OILY WASTES
Techniques commonly used by electrolaters and metal finishers to remove
oils include skimming, coalescing, emulsion breaking, flotation, centrifu-
gation, ultrafiltration, and reverse osmosis. Treatment of oily wastes is
most efficient and cost effective if oils are segregated from other wastes and
treated separately. The process of separation varies depending on the type of
oil involved.
4.7 IN-PLANT CONTROL OF TOXIC ORGANICS
The primary control technology for toxic organics is proper storage of
concentrated toxic organics without discharging directly into wastestreams and
segregation from other wastes that will enter the waste treatment system.
Spent degreasing solvents may be segregated from other wastes by providing and
identifying the necessary storage containers, training personnel in the use of
the techniques, and holding periodic check-ups to ensure that proper segre-
gation is occurring. The separate waste solvents can then be recovered
on-site or contract hauled.
Using cleaning techniques that require no solvents will eliminate or
reduce the quantity of toxic organics found in wastewater. Cleaning tech-
niques may include wiping, immersion, spray techniques using water, alkaline
and acid mixtures, and solvent emulsions.
Toxic organics that enter the wastestreams can be removed by treatment
technologies used for the control of other pollutants. Toxic organics tend to
be more soluble in oil and grease than in water. Thus removal of oil and
grease will reduce the discharge of toxic organics. Other possible mechanisms
for removal include adsorption, settling, and volatilization, which can occur
during treatment of metals, cyanide, and oil and grease.
Specific treatment technologies which are not part of the technology
basis of the regulation but are applicable for the treatment of TTO include
carbon adsorption and reverse osmosis, resin adsorption, ozonation, chemical
oxidation, and aerobic decomposition.
4-5
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4.8 TREATMENT OF SLUDGES
Sludges are created by waste treatment technologies which remove solids
from wastewater. Sludge thickening is used to concentrate dilute sludges by a
mechanical device such as a vacuum filter or centrifuge. Doubling the solids
content reduces capital and operating costs and. reduces costs for hauling.
Pressure filtration is achieved by pumping the liquid through a filter materi-
al which is impenetrable to the solid phase. Sludge bed drying is employed to
reduce the water content of sludges so that they can be mechanically collected
for removal. Sludge may then be transported to landfills or incinerated.
Additional removal methods for industrial waste sludges include chemical
containment, encapsulation, fixation, and thermal conversion.
4.9 IN-PROCESS CONTROL TECHNOLOGIES
In-process control techniques have been developed and are being utilized
by electroplaters and metal finishers. These techniques deal with reducing
water usage, reducing drag out of pollutants and efficient handling of process
wastes and include:
- Flow reduction through efficient rinsing
- Countercurrent and static rinsing
- Process bath conservation
- Waste oil segregation
- Process bath segregation
— Process modification
- Cutting fluid cleaning
- Integrated waste treatment
- Good housekeeping
Reducing the water usage at metal finishing facilities is the most
important control and results in reduced pollutant discharge and consequently
reduced costs for wastewater treatment. It is estimated that rinse steps
consume most of the water used at metal finishing facilities. Therefore,
efficient rinse systems would lead to the greatest water use reductions.
Several rinsing techniques are currently used at metal finishing facilities.
4-6
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Of these, the countercurrent rinse provides for the most efficient water
usage, and consists of only one fresh water feed introduced in the last tank.
The dead or static rinse is applicable for initial rinsing after metal plating
and allows for easier metals recovery and lower water usage.
4-7
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5.
REQUIREMENTS OF THE GENERAL PRETREATMENT REGULATIONS
5.1 INTRODUCTION
This section provides a brief overview of the General Pretreatment
Regulations and identifies those provisions of the Regulations which have a
direct bearing on the application and enforcement of Categorical Pretreatment
Standards for the Electroplating and Metal Finishing category.
The General Pretreatment Regulations for Existing and New Sources (40 CFR
Part 403) establish the framework and responsibilities for implementation of
the National Pretreatment Program. The effect of 40 CFR Part 403 is essen-
tially three-fold. First, the General Pretreatment Regulations establish
general and specific discharge prohibitions as required by Sections 307(b) and
(c) of the Clean Water Act. The general and specific prohibitions are de-
scribed in Section 403.5 of the Pretreatment Regulations and apply to all
nondomestic sources introducing pollutants into a POTW whether or not the
source is subject to Categorical Pretreatment Standards.
Second, the General Pretreatment Regulations establish an administrative
mechanism to ensure that National Pretreatment Standards (Prohibited Discharge
Standards and Categorical Pretreatment Standards) are applied and enforced
upon industrial users. Approximately 1,700 POTWs are required to develop a
locally run pretreatment program to ensure that non-domestic users comply with
applicable pretreatment standards and requirements.
Third, and most importantly for the purposes of this guidance manual, the
General Pretreatment Regulations contain provisions relating directly to the
implementation and enforcement of the Categorical Pretreatment Standards.
Reporting requirements, local limits,"monitoring or sampling requirements, and
category determination provisions are discussed. POTW representatives should
refer to 40 CFR Part 403 for specific language and requirements where appro-,
priate.
5-1
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5.2 CATEGORY DETERMINATION REQUEST
An existing industrial user (IU) or its POTW may request written
certification from EPA or the delegated State specifying whether or not the
industrial user falls within a particular industry category or subcategory and
is subject to a categorical pretreatment standard. Although the deadline for
submitting a category determination request by existing industrial users
subject to the electroplating and metal finishing categorical pretreatment
standards has passed, a new industrial user or its POTW may request this
certification for a category determination anytime prior to commencing its
discharge. The contents of a category determination request and procedures
for review are presented in Section 403.6(a) of the General Pretreatment
Regulations.
5.3 MONITORING AND REPORTING REQUIREMENTS OF THE GENERAL PRETREATMENT
REGULATIONS
In addition to the requirements contained in the Electroplating and Metal
Finishing Categorical Pretreatment Standards, industrial users subject to
these Standards must fulfill the reporting requirements contained in Section
403.12 of the General Pretreatment Regulations. These requirements include
the submission of baseline monitoring reports, compliance schedules, compli-
ance reports (initial and periodic), notices of slug loading, and record-
keeping requirements. Each of these reporting requirements is briefly
summarized below.
5.3.1 Baseline Monitoring Reports
All industrial users subject to Categorical Pretreatment Standards must
submit a baseline monitoring report (BMR) to the Control Authority. The
purpose of the BMR is to provide information to the Control Authority to
document the industrial user's current compliance status with a Categorical
Pretreatment Standard. The Control Authority is defined as the POTW if it has
an approved pretreatment program, otherwise the BMR will be submitted to the
State (if the State has an approved State Pretreatment Program) or to the EPA
Region. Additional guidance on BMR reporting is available from the EPA
Regional Pretreatment Coordinator.
5-2
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BMR Due Dates
Section 403.12(b) requires that BMRs be submitted to the Control
Authority within 180 days after the effective date of a Categorical Pretreat-
ment Standard or 180 days after the final administrative decision made upon a
category determination request [403.6(a)(4)], whichever is later. Table 5.1
shows the respective due dates for electroplating and metal finishing BMRs.
BMR Content
A BMR must contain the following information as required by Section
403.12(b).
1.
2.
3.
4.
Name and address of the facility, including names of operator(s) and
owner(s).
List of all environmental control permits held by or for the
facility.
Brief description of the nature, average production rate and SIC code
for each of the operation(s) conducted, including a schematic process
diagram which indicates points of discharge from the regulated
processes to the POTW.
Flow measurement information for regulated process streams discharged
to the municipal system. Flow measurements of other wastestreams
wxll be necessary if application of the combined wastestream formula
is necessary.
Identification of the pretreatment standards applicable to each
regulated process and results of measurements of pollutant concen-
trations and/or mass. All samples must be representative of daily
operations and results reported must include values for daily maximum
and average concentration (or mass, where required). Where the flow
of the regulated stream being sampled is less than or equal to
250,000 gallons per day, the industrial user must take three samples
With±oCn tW° WSek Period« Where the flow of the stream is greater
than 250,000 gallons per day, the industrial user must take six sam-
ples within a two week period. If samples cannot be taken immediate-
ly downstream from the regulated process and other wastewaters are
mixed with the regulated process, the industrial user, should measure
flows and concentrations of the other wastestreams sufficient to
allow use of the combined wastestream formula. Requirements for
demonstrating compliance with TTO standards are discussed in Section
5.4.1.
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TABLE 5.1
DUE DATES FOR SUBMISSION OF
BASELINE MONITORING REPORTS
Existing Indirect Dischargers
Non-integrated
Job Shops &
IPCBM's
Integrated
Job Shops
IPCBM's
Non-integrated
Captives
Integrated
Captives
Electroplating
(Part 413)
Metals and
Cyanide
Electroplating
(Part 413)
TTO
September 12, 1981 June 25, 1983 September 12, 1981 June 25, 1983
February 24, 1984 February 24, 1984
Metal Finishing
(Part 433)
Metals, Cyanide,
and TTO
February 24, 1984 February 24, 1984
Note: If a request for a category determination has been made, then the BMR is due 180 days
after the final decision on the category determination.
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6. Statement of certification concerning compliance or noncompliance
with the Pretreatment Standards.
7.
If not in compliance, a compliance schedule must be submitted with
the BMR that describes the actions the user will take and a timetable
for completing those actions to achieve compliance with the standard.
This compliance schedule must contain specific increments of progress
in the form of dates for the commencement and completion of major
events, however, no increment of the schedule shall exceed 9 months.
Within 14 days of each completion date in the schedule, the indus-
trial user shall submit a progress report to the Control Authority
indicating whether or not it complied with the increment of progress
to be met on such date, and, if not, the date on which it expects to
comply with this increment of progress and the steps being taken to
return to the schedule.
BMR Reporting of Toxic Organics :
Since promulgation of the Metal Finishing pretreatment standards, some
questions have been raised regarding BMR reporting of total toxic organics
(TTO). BMR sampling requirements clearly apply to all regulated metals.
However, since monitoring for toxic organics can be expensive, BMR sampling
and analysis for TTO will only be required for those organics "which would
reasonably be expected to be present" in the industrial user's effluent [Sec-
tion 413.03(c)]. For routine compliance monitoring, not BMR monitoring, the
regulations allow for the IU to certify that the regulated toxic organics are
not used at the facility or to present a plan demonstrating appropriate con-
trols to prevent organic compounds from entering the wastestream. Even if the
industrial user expects to use the certification procedure to demonstrate
regular compliance with the TTO limitation, the user must still sample and
analyze for any toxic organic "reasonably expected to be present" for the
purposes of the baseline monitoring report. If no toxic organics are used or
expected to be discharged, then no TTO monitoring is required for the BMR.
5.3.2 Report on Compliance
Within 90 days after the compliance date for the Electroplating and Metal
Finishing Pretreatment Standards or in the case of a New Source following
commencement of the introduction of wastewater into the POTW, any industrial
user subject to the Standards must submit to the Control Authority a "report
on compliance" that states whether or not applicable pretreatment standards
5-5
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are being met on a consistent basis. The report must indicate the nature and
concentration of all regulated pollutants in the facility's regulated process
wastestreams; the average and maximum daily flows of the regulated streams;
and a statement of whether compliance is consistently being achieved, and if
not, what additional operation and maintenance and/or pretreatment is neces-
sary to achieve compliance. See 40 CFR 403.12>(d).
5.3.3 Periodic Reports on Continued Compliance
Unless required more frequently by the Control Authority, all industrial
users subject to the Electroplating and Metal Finishing Categorical Pretreat-
ment Standards must submit a biannual "periodic compliance report" during the
months of June and December. The report shall indicate the precise nature and
concentrations of the regulated pollutants in its discharge to the POTW, the
average and maximum daily flow rates of the facility, the methods used by the
indirect discharger to sample and analyze the data, and a certification that
these methods conformed to those methods outlined in the regulations. See 40
CFR 403.12(e).
5.3.4 Notice of Slug Loading
Section 403.12(f) requires industrial users to notify the POTW imme-
diately of any slug loading of any pollutant, including oxygen demanding
pollutants (BOD, etc.) released to the POTW system at a flow rate and/or
pollutant concentration which will cause interference with the POTW.
5.3.5 Monitoring and Analysis to Demonstrate Continued Compliance
Section 403.12(g) states that the frequency of monitoring to demonstrate
continued compliance shall be prescribed in the applicable Pretreatment Stan-
dard. Neither the Electroplating nor Metal Finishing Pretreatment Standard
establish any monitoring frequency. Therefore, the appropriate Control Auth-
ority must establish the monitoring frequency to adequately demonstrate that
indirect dischargers subject to these pretreatment standards are in compliance
with the applicable standards. Unless otherwise noted in the appropriate
paragraph of Section 403.12, the monitoring frequency established by the Con-
trol Authority shall be used in the baseline monitoring report (403.12(b)(5)),
5-6
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the report on compliance with categorical pretreatment standard deadline
(403.12(d)), and the periodic reports on continued compliance (403.12(e)).
Sampling and analysis shall be in accordance with the procedures estab-
lished in 40 CFR Part 136 and any amendments to it or shall be approved by
EPA. When Part 136 techniques are not available or are inappropriate for any
pollutant, then sampling and analysis shall be conducted in accordance with
procedures established by the POTW or using any validated procedure. However,
all procedures for sampling and analysis not included in Part 136 must be
approved by EPA.
5.3.6 Signatory Requirements for Industrial User Reports
All reports submitted by industrial users (BMR, Initial Report on
Compliance, and Periodic Reports, etc.) must be signed by an authorized
representative in accordance with Section 403.12(k).
5.3.7. Recordkeeping Requirements
Any industrial user subject to the reporting requirements of the General
Pretreatment Regulations shall maintain records of all information resulting
from any monitoring activities required by 403.12 for a minimum of three years
[403.12(n)].- These records shall be available for inspection and copying by
the Control Authority.
5.4 SPECIAL INDUSTRIAL SELF-MONITORING CONSIDERATIONS
5.4.1 Toxic Organics Certification
In lieu of monitoring for TTO, the Control Authority may allow dis-
chargers subject to Electroplating and Metal Finishing regulations to certify
that no dumping of toxic organics to the wastestream has occurred. In cases
where monitoring to determine TTO compliance is necessary, sampling and
analysis for TTO will only be required for those organics "which would
reasonably be expected to be present" in the industrial user's effluent
[Section 413.03(c)]. When dischargers request that no monitoring be required,
they must submit a toxic organic management plan that specifies the toxic
organic compounds used, the method of disposal used (instead of dumping into
5-7
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wastestreams), and procedures for assuring that toxic organics do not routine-
ly spill or leak into wastewater discharged to the POTW. This certification
is added as a comment to the baseline monitoring report as well as periodic
reports.
A toxic management plan provides methods for the reduction of toxics in
effluents and assists industrial facilities in achieving compliance with
Categorical Pretreatment Standards. An example of a toxic organic management
plan that is required when industrial users wish to certify that no discharge
of toxic pollutants has occurred is presented below.
The plan has three basic steps:
Step 1 - Process engineering analysis should consist of:
a. An examination of published reports on the specific industry;
b. A water flow diagram to identify all possible wastewater sources;
c. A list of raw materials used in the industrial processes, including
chemical additives, water treatment chemicals and cleaning agents,
and the wastewater stream that each material potentially enters;
d. Comparison of the toxics found in the effluent with the list of raw
materials and selection of the most probable wastewater source;
e. Evaluation of the toxics found in the effluent, but not on the raw
materials list and determination of those formed as reaction products
or by-products;
f. Examination of sources such as equipment corrosion or raw materials
impurities contributing inorganic pollutants.
Step 2 - Pollutant control evaluation should be determined on a case-by-
case basis and may include:
a. Inplant process modification, including chemical substitution,
partial or complete recycling, reuse, neutralization, ion exchange,
or operation changes.
5-8
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Step 3 - Toxics reduction evaluation report is submitted to the Control
Authority and contains:
a. Identification of source(s) of pollutant(s).
b. Control options explored.
c. Effectiveness of control options in meeting effluent limits.
d. Industrial user's choice of options and the projected schedule for
achieving necessary control.
In certain cases, the industrial user will not achieve compliance with
the effluent standard. In these cases, additional evaluations will be
necessary. ,
5.4.2 Self-Monitoring for Cyanide
For facilities subject to Metal Finishing regulations, self-monitoring
for cyanide must be conducted after cyanide treatment and before dilution with
other wastestreams. Alternatively, samples may be taken of the final effluent
if the plant limitations are adjusted based on the dilution ratio of the
cyanide wastestream flow to the effluent flow.
5.5 APPLICATION OF THE COMBINED WASTESTREAM FORMULA
One provision of the General Pretreatment Regulations that will often be
necessary for POTWs and industries to properly monitor and report on compli-
ance with Categorical Pretreatment Standards is the Combined Wastestream
Formula (CWF) [40 CFR 403.6(e)]. The CWF is a mechanism for calculating
appropriate limitations specified in applicable regulations to a wastewater in
which process wastestreams are mixed with regulated, unregulated or dilution
streams, thereby resulting in a mixed effluent. The CWF is applied to the
mixed effluent to account for the presence of the additional wastestreams.
The following definitions and conditions are important to the proper use
of the CWF.
5-9
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Definitions
• Regulated Process Wastestream - an industrial process wastestream
regulated by National Categorical Pretreatment Standards.
• Unregulated Process Wastestream - an industrial process wastestream
that is not regulated by a categorical standard.
Note:
Definitions apply to individual pollutants. A wastestream from a
process may be "regulated" for one pollutant and "unregulated" for
another.
o Dilute Wastestream - Boiler blowdown, sanitary wastewater, noncontact
cooling water or blowdown, and Paragraph 8 excluded wastestreams
containing none of the regulated pollutant or only trace amounts of
it.
» Concentration-based Limit - a limit based on the relative strength of
a pollutant in a wastestream, usually expressed in mg/1 (Ib/gal).
• Mass-based Limit - a limitation based on the actual quantity of a
pollutant in a wastestream, usually expressed in mg/some unit of
production for a given operation such as square meter (Ib/square foot
per operation).
CWF Conditions
To ensure proper application of the CWF, the following conditions must be
met by a municipality and its industries [40 CFR 403.6(e)]:
• Alternative discharge limits that are calculated in place of a
Categorical Pretreatment Standard must be enforceable as Categorical
Standards.
• Calculation of alternative limits must be performed by the Control
Authority (POTW) or by the industrial user with written permission
from the POTW.
• Alternative limits must be established for all regulated pollutants in
each of the regulated processes.
• The Control Authority and/or the industrial user may use mass-based
limitations in place of the concentration-based limitations, when they
are provided for by a given Categorical Pretreatment Standard such as
electroplating, as long as a prior agreement exists between the
regulated industrial user and the municipality that is receiving these
wastes.
• Both daily maximum and long-term average (usually monthly) alternative
limits must be calculated for each regulated pollutant.
5-10
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9 If process changes at an industry.warrant, the Control Authority may
recalculate the alternative limits at its discretion or at the request
of the industrial user. The new alternative limits must be calculated
and become effective within 30 days of the process change.
• The Control Authority may impose stricter alternative limits, but may
not impose alternative limits that are less stringent than the
calculated limits.
® A calculated alternative limit cannot be used if it is below the
analytical detection limit for that pollutant. If a calculated limit
is below the detection limit, the IU must either: 1) not combine the
dilute streams before they reach the combined treatment facility or
i) segregate all wastestreams entirely.
« The categorical standards of the regulated wastestreams which are
applied to the CWF must be consistent in terms of the number of
samples the standard is based on. Electroplating wastestreams are
regulated by a 4-day average standard and are not consistent with
other categorical standards regulated by a maximum monthly average
Qbased on 10 sample days) standard. According to 40 CFR Part 413.04
if a non-electroplating wastestream is regulated by a monthly average
standard and'is combined with an electroplating wastestream, monthly
standards rather than 4-day average standards are to be used in
calculating an alternative limit with the CWF. Also, if two electro-
plating wastestreams regulated under different subcategories of the
electroplating regulations are combined, the 4-day limits may be used
to calculate the alternate limits, unless an additional wastestream
subject to monthly standards is added. The following equivalent
monthly averages (based on 10 sample days per month) have been
developed for use in the CWF:
Pollutant
Cadmium (T)
Chromium (T)
Copper (T)
Lead (T)
Nickel (T)
Zinc (T)
Silver (T)
Total Metals
Cyanide, A
Cyanide (T)
Equivalent Monthly
Average (mg/1)
0.63
3.56
2.44
0.37
2.38
2.37
0.63
6.26
2.37
0.87
5-11
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Monitoring Requirements For Industrial Users Using the CWF
Self-monitoring requirements by an industrial user are necessary to
ensure compliance with the alternative categorical limit. Because neither
the Metal Finishing nor Electroplating Pretreatment Standards include self-
monitoring requirements, the Control Authority will establish minimum self-
monitoring requirements.
Application of the CWF
The actual combined wastestream formulas are presented in Table 5.2.
Tables 5.3 and 5.4 present an example of how the CWF is used to calculate
alternative limits and four example calculations applied to specific electro-
plating/metal finishing situations. Three of the examples differ because of
the individual compliance deadlines for the different categorical pretreatment
standards. The fourth example represents an example showing conversion from a
production (mass) based standard to a concentration based standard. It is
important to remember that when two or more regulated wastestreams are mixed
prior to treatment, before using the CWF it is necessary to determine which
pretreatment regulation applies to each regulated wastestream before they are
mixed.
5.6 REMOVAL CREDITS
A removal credit allows a POTW to provide categorical industrial users of
its system with a credit (in the form of adjusted categorical pretreatment
standards) for removal of pollutants by the POTW. Industrial users receiving
such a credit are allowed to discharge to the POTW greater quantities of regu-
lated pollutants than otherwise permitted by applicable categorical standards.
Whether or not to seek authority to grant removal credits is completely at the
discretion of the POTW. Section 403.7 of the General Pretreatment Regulations
establishes the conditions under which a POTW would obtain approval to grant
removal credits and specifies the means by which these removal credits are to
be determined.
In 1977, Congress amended section 307(b) of the Clean Water Act to
provide for removal credits. EPA originally implemented that provision and
established the conditions under which POTWs could obtain authorization to
5-12
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TABLE 5.2
COMBINED WASTESTREAM FORMULAS
Alternative Concentration Limit Formula:
ct =
F.
C - alternative concentration limit for the pollutant
C. - Categorical Pretreatment Standard concentration limit for the pollutant
in regulated stream i
F - average daily flow (at least 30 day average) of regulated stream i
F, - average daily flow (at least 30 day average) of dilute wastestream(s)
F - average daily flow (at least 30 day average) through the combined
treatment facility (including regulated, unregulated and dilute
wastestreams)
N — total number of regulated streams
Alternate Mass Limit Formula
N
X
Ft - Fd
~N "
Z
i=l F,
M - alternative mass limit for the pollutant
M. - Categorical Pretreatment Standard mass limit for the pollutant in
regulated stream i
F - average daily flow (at least 30 day average) of regulated stream i
F, - average daily flow (at least 30 day average) of dilute wastestream(s)
F - average daily flow (at least 30 day average) through the combined
treatment facility (including regulated, unregulated and dilute
wastestreams)
N - total number of regulated streams.
5-13
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TABLE 5.3
COMBINED WASTESTREAM FORMULA EXAMPLE CALCULATION
The following examples provide the calculations for determining alternate
discharge limits using the combined wastestream formula. The examples, assume
combinations of various industries with the following wastestreams:
Industrial
Category
(Subcategory)
Electroplating
(Common Metals)
Metal Finishing
(Electroplating)
(Coating and Painting)
Porcelain Enameling
(Steel-coating only)
Copper Forming
Sanitary Waste
Daily Max.
Wastestream
Type
Regulated
Regulated
)
Regulated
Regulated
Flow
(mgd)
0.4
0.4
0.1
0.075
0.4
Zn Limit
(mg/1)
4.22
2.61
2.61
1.333
Mass/Produc-
Compliance
Date
June 30, 1984
February 15, 1986
November 25, 1985
August 15, 1986
Dilution
0.05
4
tion Based
N/A
N/A
These are not subcategories; they are metal finishing processes.
2 2
Alternate production based limit = 164 mg/m plated.
3 2
Alternate Mass/Production based limits = 53.3 mg/m for preparation and 0.85
2
mg/m for coating.
4
Mass/Production based limits = 0.943 mg/off-kg of copper heat treated for
solution heat treatment.
The calculated alternate discharge limits (Zn ) in the following examples
cwr
are based on phased compliance dates for Electroplating, Porcelain Enameling,
and Metal Finishing.
5-14
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TABLE 5.4
COMBINED WASTESTREAM FORMULA EXAMPLE CALCULATION
EXAMPLE A
Alternative discharge limit for integrated electroplater/porcelain
enameler from June 30, 1984 (compliance date for electroplating) until
November 25, 1985 (compliance date for porcelain enameling).
Electroplating
(Common Metals)
Metal Finishing
(Coating & Painting)
Q = 0.4 mgd
Zn = 4.2 mg/1
Porcelain
Enameling (Steel)
Q = 0.1 mgd
Zn = N/A
Q = 0.075 mgd
Zn = N/A
Q = 0.05 mgd
Zn = N/A
Zn
(4.2 mg/1 x 0.4 mgd) X (0.4 mgd + 0.1 mgd + 0.075 mgd' + 0.05 mgd - 0.05 mgd)
cwf 0.4 mgd 0.625 mgd
Zn = 3.86 mg/1
Note: Due to dilution from sanitary waste, the applicable Zn limit, 4.2 mg/1,
is reduced to 3.86 mg/1.
5-15
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TABLE 5.4 (Continued)
COMBINED WASTESTREAM FORMULA EXAMPLE CALCULATION
EXAMPLE B
Alternative discharge limit for integrated electroplater/porcelain
enameler from November 25, 1985 until February 15, 1986 (compliance date for
metal finishing)
Q = 0
Zn » 4
Electroplating
(Common Metals)
.4 mgd
.2 mg/1
Metal Finishing
(Coating & Painting)
Q = 0.1 mgd
Zn = N/A
Porcelain
Enameling (Steel)
Q = 0.075 mgd
Zn = 1.33 mg/1
Q = 0
Sanitary
Waste
.05 mgd
Zn = N/A
Zn
cwf
4.2 mg/1 (0.4 mgd) + 1.33 mg/1 (0.075 mgd)
(0.4 mgd + 0.075 mgd)
(0.4 mgd +0.1 mgd + 0.075 mgd + 0.05 mgd - 0.05 mgdj
0.625 mgd
Zn , - 3.45 mg/1
cwf
Note: Alternate discharge limit is based on Electroplating and Porcelain
Enameling categorical standards and proportioned by the flow of the
regulated electroplating and porcelain enameling wastestreams. Due to
dilution from sanitary waste, the alternate discharge limit is reduced.
5-16
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TABLE 5.4 (Continued)
COMBINED WASTESTREAM FORMULA EXAMPLE CALCULATION
EXAMPLE C
Alternative discharge limit for integrated electroplater/porcelain
enameler after February 15, 1986 (compliance date for metal finishing).
Q
Zn
Metal Finishing
(Electroplating
Common Metals)
=0.4 mgd
=2.61 mg/1
Q =
Zn =
Metal Finishing
(Coating & Painting)
= 0. 1 mgd
= 2.61 mg/1
Porcelain
Enameling (Steel)
Q = 0.075 mgd
Zn = 1.33 mg/1
Sanitary
Waste
Q = 0.05 mgd
Zn = N/A
Zn
cwf
1
2.61. mg/1 (0.5 mgd) + 1 ."33 mg/1 (0.075 mgd)
(0.5 mgd + 0.075 mgd)
(0.5 mgd +. 0.075 mgd + 0.05 mgd - 0.05 mgd)
0.625 mgd
Zncwf = 2'25
Note:
Electroplating (common metals) is now covered by Metal Finishing, and
is subject to a Zn limit of 2.61 mg/1. Thus, the alternate discharge
limit is based on Metal Finishing and Porcelain Enameling categorical
standards and proportioned by the flow of the three regulated waste-
streams. Due to dilution from sanitary waste, the alternate discharge
limit is reduced to 2.25 mg/1.
5-17
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TABLE 5.4 (Continued)
COMBINED WASTESTREAM FORMULA EXAMPLE CALCULATION
EXAMPLE D
Copper Forming and several other categorical standards are expressed as
production-based limits. The example below converts production-based limits
to equivalent concentration-based limits. These equivalent concentration-
based limits can then be used as the standard for Copper Forming.
Copper Forming (Solution Heat Treatment) = 0.943 mg/off-kg of copper heat
Maximum Daily Limit for Zinc treated
Average Daily Production During
Last 12 months
Average Daily Water Usage in
Solution Heating Treating
During Last 12 months
= 30,000 off-kg of copper heat
treated per day
= 400,000 gpd
Step 1: Convert Production-based Limit to Equivalent Concentration Limit
Concentration _ (Production-Based Limit) (Avg. Daily Production Rate) -
Equivalent ~ (Avg. Daily Flow from Regulated Process) (Conversion Factor)
0.943 mg/off-kg (30,000 off-kg/day) = 0>(n9
Zn(equivalent) 400,000 gpd (3.785 liters/gallon)
Step 2: Once the concentration-based equivalent is determined, then the
alternate limit can be calculated as in Example A.
Q
Zn
Zn
0.
0.
Copper Forming
(Solution Heat
Treatment)
4 mgd
019 mg/1
Q =
Zn =
Metal Finishing
(Coating & Painting)
0.1 mgd
2.61
Q = 0.
Zn = 1.
07
33
Porcelain
Enameling (Steel)
5 mgd
Sanitary
Waste
Q = 0.05 mgd
Zn = N/A
j
(0.019 me/1
cwf
(0.4 mgd + 0.1 mgd + 0.075 mgd)
(0.4 mgd +0.1 mgd + 0.075 mgd + 0.05 mgd - 0.05 mgd)
0.625 mgd
Zn f - 0.59 mg/1
cwf
Note: Off-kg shall mean the mass of copper ore copper alloy removed from a forming
or ancillary operation at the end of a process cycle for transfer to a
different machine or process.
5-18
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TABLE 5.4 (Continued)
COMBINED WASTESTREAM FORMULA EXAMPLE CALCULATION
EXAMPLE E
For the several categorical standards shown in Example D, permit authori-
ties may wish to utilize mass limits. The example below converts concentra-
tion .limits £o mass-based limits and utilizes the production-based limits (and
alternate limits).
Copper Forming r
Copper Forming (Solution Heat Treatment) =
Maximum Daily Limit for Zinc
Average Daily Production During
Last 12 months
Average Daily Water Usage in
Solution Heat Treating
During Last 1.2 months
Allowable Zn Mass = 0.943 (30,000)
Metal Finishing
Metal Finishing Maximum Daily
Limit for Zinc
Average Daily Production During
Last 12 months
Average Daily Water Usage in
Metal Finishing
Allowable Zn Mass = 2.61 (100,000 x 3.78)=
Porcelain Enameling
Porcelain Enameling (steel basis material)
Maximum Daily Limit for Zinc
0.943 rag/off-kg of copper heat
treated
30,000 off-kg of copper heat
treated per day
400,000 gpd
28,290 mg
2.61 mg/1
not required
100,000 gpd
986,580 mg
Average Daily Production During
Last 12 months
= (53.3 + 0.85) mg/m2 of area
processed or coated thru metal
preparation and coating
operation, respectively.
2
5570 m of preparation
2
7250 m of coating
5-19
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TABLE 5.4 (Continued)
COMBINED WASTESTREAM FORMULA EXAMPLE CALCULATION
EXAMPLE E (Continued)
Average Daily Water Usage in
Porcelain Enameling
Allowable Zn Mass
75,000 gpd
= 53.3(5570)+0.85(7250)=303,044 mg
Copper Forming
(Solution Heat
Treatment)
Metal Finishing
(Coating & Painting)
Porcelain
Enameling (Steel)
Sanitary
Waste
Zn - 28,290 + 986,580 + 303,044
cwf
= 1,317,914 mg/day
Zn -1.3 kg/day or (2.86 Ibs/day)
cwf
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grant removal credits in the June 26, 1978 General Pretreatment Regulations.
On January 28, 1981, the removal credits provision, as well as many other
portions of the pretreatment regulations, were amended. Under the 1981
provision, any POTW seeking removal credit authority was required to demon-
strate its removal performance by sampling its influent and effluent and
calculating its removal rates based on this data. Removal capability of each
POTW, therefore, was to be determined on a case-by-case basis. In addition to
the sampling requirements the provision specified the other prerequisites for
obtaining removal credit authority. Only the Approval Authority (either EPA
or the State) can grant removal credit authority to a POTW.
A revised removal credit regulation was proposed on September 28, 1982
(47 Fed. Reg. 42698). The final regulation on removal credits is due for
promulgation in March 1984. Until then, POTWs may apply for removal credit
authority under the existing procedures contained in Section 403„7 of the
January 28, 1981 General Pretreatment Regulations.
5.7 FUNDAMENTALLY DIFFERENT FACTORS VARIANCE
A request for a fundamentally different factors (FDF) variance is a
mechanism by which a Categorical Pretreatment Standard may be adjusted, making
it more or less stringent, on a case-by-case basis. If an indirect dis-
charger, a POTW, or any interested person believes that the factors relating
to a specific indirect discharger are fundamentally different from those
factors considered during development of the relevant categorical pretreatment
standard and that the existence of those factors justifies a different
discharge limit from that specified in the Categorical Standard, then they may
submit a request to EPA for such a variance (See 40 CFR 403.13).
This section was the subject of a recent court decision (U.S. Court of
Appeals for the Third Circuit) in September of 1983. The Court held that the
EPA lacks authority to issue variances to indirect dischargers for toxic pol-
lutants. As a result of the Court's decision, FDF variances can only be
granted for non-toxic pollutants. Since the electroplating and metal finish-
ing categorical standards contain limits only for toxics, no variance is
available for this industry.
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5.8 LOCAL LIMITS
Local limits are numerical pollutant concentration or mass-based values
that are developed by a POTW for controlling the discharge of conventional,
non-conventional or toxic pollutants from indirect sources. They differ from
National Categorical Pretreatment Standards in that Categorical Pretreatment
\
Standards are developed by EPA and are based upon the demonstrated performance
of available pollutant control technologies (for specific categorical indus-
tries). These national technology-based categorical standards do not consider
local environmental criteria or conditions, and are only developed to assure
that each industry within a specified category meets a minimum discharge
standard which is consistent across the United States for all POTWs. Local
limits, on the other hand, are developed to address specific localized impacts
on POTWs and their receiving waters. Local limitations are typically designed
to protect the POTW from:
• The introduction of pollutants into the POTW which could interfere
with its operation
t> Pass-through of inadequately treated pollutants which could violate a
POTW's NPDES permit or applicable water quality standards
« The contamination of a POTW's sludge which would limit sludge uses or
disposal practices.
Local limits, as the name implies, take into consideration the factors
that are unique to a specific POTW^ whereas categorical pretreatment standards
are developed only for a general class of industrial dischargers. Local
limits are required under 40 CFR 403.5 and must be developed when it is
determined that Categorical Pretreatment Standards are not sufficient to
enable the POTW to meet the above three Pretreatment Program objectives.
To assist municipalities in developing defensible and technically sound
numerical effluent limitations, EPA has prepared some general guidelines on
limit development in its document "Guidance Manual for POTW Pretreatment
Program Development." Appendix L of this document lists the general method-
ology, required formulas and typical environmental criteria used to develop
local limits. This manual is available from EPA Regional offices and NPDES
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States and should be carefully followed when developing local limits. Al-
though a detailed discussion of local limit development is beyond the scope of
this document, the general methodology includes the following four steps:
Step 1 - Determine the maximum headworks loading (for each specific
pollutant) that will assure that the three fundamental objec-
tives of the pretreatment program are met.
Step 2 - Calculate the allowable loading to the POTW by subtracting the
uncontrollable portion of pollutant discharge to the POTW (from
domestic, commercial and infiltration/inflow sources) from the
total headwork loading value.
Distribute the controllable loading to industrial users through
an allocation process.
Step 3
Step 4 - Derive specific local limits from the allocation results.
The above four step process must be performed for each pollutant which
the POTW determines may need a specific local limitation. As a general rule,
the limit setting analysis should be performed for all pollutants which are
discharged to the POTW in significant quantities. The POTW should identify
pollutants of concern through an evaluation of the POTW's industrial waste
survey. A procedure for evaluating industrial waste survey results is
included in the EPA guidance manual mentioned earlier.
To assist POTWs with the development of local limits EPA has developed a
computer program that incorporates the .general methodology required to develop
local limits-'and alleviates a substantial amount of the tedious calculations
required to develop these limits. This computer program has the following
capabilities to aid the POTW in limit development:
• Performs the four-step limit setting analysis on microcomputer or
mainframe
« Screens input data provided by the POTW
• Supplements POTW data with "built-in" files containing data on
Industrial/Municipal wastewater characteristics, POTW removal rates,
and POTW inhibition values
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• Allocates controllable pollutant loads using several different
methodologies
• Compares calculated local limits to EPA Categorical Standards.
POTWs may obtain information on this computer program by contacting any of the
ten EPA Regional offices. Instructions will be provided on how to use the
computer program as well as how to access a computer system which supports it.
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REFERENCES
Electroplating
Final Regulations Promulgated
Correction Notice (Typographical errors)
Correction Notice
(Delayed compliance for Integrated Facilities)
Revision to 9/07/79 Promulgation of 7/03/80
Amended (Integrated Facilities Compliance)
Amended (Added total toxic organic limit)
Amended (Allows PSES compliance beyond 7/1/84)
Correction/Clarification Notice
(Compliance Dates)
Federal Register Notice
09/07/79
10/01/79
03/25/80
01/28/81
01/21/83
07/25/83
09/15/83
09/26/83
44FR52618
44FR56330
45FR19246
40CFR9462
48FR2774
48FR32482
48FR41410
48FR43680
Metal Finishing
Final Regulations Promulgated
Amended (Allows PSES Compliance beyond 7/1/84
Correction/Clarification Notice
(Compliance Dates)
Correction Notice (Typographical Errors)
07/15/83
09/15/83
09/26/83
10/03/83
48FR32485
48FR41410
48FR43681
48FR45105
General Pretreatment Regulations
40 CFR Part 403, 46 FR 9404
01/28/81
Final Development Document -
Electroplating
Final Development Document -
Metal Finishing
August 1979
June 1983
440/1 - 79/003
440/1 - 83/091
Guidance Manual for POTW
Pretreatment Program Development
Procedures Manual for Reviewing
a POTW Pretreatment Program
Submission
October 1983
October 1983
Copies of the technical and economic documents may be obtained from the
National Technical Information Services, Springfield, VA. 22161
(703/487-4650). Pretreament Program Manuals may be obtained from U.S. EPA,
Permits Division (EN-336), Washington, D.C. 20460
*U.S. Goxrnnwnt Printing Ofltei: ISO*—4t1-1*1/46111
R-l
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