SEPA
United States
Environmental Protection
Agency
Office of
Solid Waste
Washington, D.C. 20460
EPA/530-SW-88-0009-I
May 1988
Solid Waste
Best
Demonstrated
Available Technology
(BOAT) Background
Document for
F006
Proposed
Volume 13
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U.S. Environmental Protection Agency
Office of Solid Waste
401 M Street, S.W.
Washington, D.C. 20460
James R. Berlow, Chief John Keenan
Treatment Technology Section Project Manager
May 1988
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TABLE OF CONTENTS
Executive Summary i
1. INTRODUCTION 1
1.1 Legal Background 1
1.1.1 Requirements Under HSWA 1
1.1.2 Schedule for Developing Restrictions 4
1.2 Summary of Promulgated BOAT Methodology 5
1.2.1 Waste Treatabi1i ty Groups 7
1.2.2 Demonstrated and Available Treatment Technologies ... 7
(1) Proprietary or Patented Processes 10
(2) Substantial Treatment 10
1.2.3 Collection of Performance Data 11
(1) Identification of Facilities for Site Visits ... 12
(2) Engineering Site Visit 14
(3) Sampling and Analysis Plan 14
(4) Sampling Visit 16
(5) Onsite Engineering Report 17
1.2.4 Hazardous Constituents Considered and Selected for
Regulation 17
(1) Development of BOAT List 17
(2) Constituent Selection Analysis 27
(3) Calculation of Standards 29
1.2.5 Compliance with Performance Standards 30
1.2.6 Identification of BOAT 32
(1) Screening of Treatment Data 32
(2) Comparison of Treatment Data 33
(3) Quality Assurance/Quality Control 34
1.2.7 BOAT Treatment Standards for "Derived From" and
"Mixed" Wastes 36
(1) Wastes from Treatment Trains Generating Multiple
Residues 36
(2) Mixtures and Other Derived From Residues 37
(3) Residues from Managing Listed Wastes or that
Contain Listed Wastes 38
1.2.8 Transfer of Treatment Standards 40
1.3 Variance from the BOAT Treatment Standard 41
2. INDUSTRIES AFFECTED AND WASTE CHARACTERIZATION 46
2.1 Industries Affected 46
2.2 Process Description 50
2.2.1 Electroplating 50
2.2.2 Anodizing 53
2.2.3 Chemical Conversion Coating 56
2.2.4 Electroless Plating 58
2.2.5 Chemical Etching and Milling 60
2.2.6 Printed Circuit Board Manufacture 60
2.3 Waste Characterization 61
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TABLE OF CONTENTS
(continued)
3. APPLICABLE TREATMENT TECHNOLOGIES 66
3.1 Applicable Treatment Technologies 66
3.2 Other Related F006 Treatment Technologies 67
3.3 Demonstrated Treatment Technologies 70
3.3.1 Stabilization of Metals 70
3.3.2 High Temperature Metals Recovery 79
3.4 Performance Data 87
4. IDENTIFICATION OF BEST DEMONSTRATED AVAILABLE TECHNOLOGY 91
5. SELECTION OF REGULATED CONSTITUENTS 95
6. CALCULATION OF BOAT TREATMENT STANDARDS 104
REFERENCES 107
APPENDIX A STATISTICAL ANALYSIS 109
APPENDIX B ANALYTICAL QA/QC PROCEDURE 121
APPENDIX C ADDITIONAL DATA 125
APPENDIX D ANALYTICAL METHOD TO MEASURE THERMAL CONDUCTIVITY ... 130
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LIST OF FIGURES
Figure No. Page
2-1 Geographic Distribution of Electroplating Facilities
Generating F006 Waste 47
2-2 General Schematic of a Wastewater Treatment System 51
3-1 Metals Recovery by Crystallization 69
3-2 Example of High Temperature Metals Recovery System 83
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LIST OF TABLES
Table No. Page
1-1 BOAT Constituent List 18
2-1 Facilities Producing F006 Waste by State and Region ... 48
2-2 Typical Electroplating Baths and Their Chemical
Composition 54
2-3 Major Constituents in F006 Waste 62
2-4 Constituent Composition for Untreated Waste 63
3-1 Cement Kiln Dust Composition Data 74
3-2 Performance Data for Raw and Stabilized F006 Waste 88
4-1 F006 TCLP Data Showing Substantial Treatment 93
5-1 List of BOAT Constituents Found in F006 Waste 96
6-1 Regulated Constituents and Calculated Treatment
Standards for F006 106
B-l Matrix Spike Recoveries for Treated Waste 123
B-2 Analytical Methods for Regulated Constituents 124
C-l Composition Data and TCLP Data for Lime Stabilized
F006 Waste 126
C-2 Composition and TCLP Data for Lime Stabilized
Phosphated Solids - F006 127
C-3 Performance Data for Stabilization of F006 Waste 128
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EXECUTIVE SUMMARY
Pursuant to section 3004(m) of the Hazardous and Solid Waste
Amendments (HSWA) enacted on November 8, 1984, the Environmental
Protection Agency (EPA) is proposing treatment standards for the listed
waste identified in 40 CFR 261.32 as F006 based on the performance of a
stabilization technology determined by the Agency to represent best
demonstrated available technology (BOAT). Compliance with these
treatment standards is a prerequisite for disposal of the waste in units
designated as land disposal units according to 40 CFR Part 268. The
proposed effective date of these standards is August 8, 1988.
In 40 CFR 261.32, waste code F006 is listed as "wastewater treatment
sludges from electroplating operations except from the following
processes: (a) sulfuric acid anodizing of aluminum; (b) tin plating on
carbon steel; (c) zinc plating (segregated basis) on carbon steel;
(d) aluminum or zinc-aluminum plating on carbon steel; (e) cleaning/
stripping associated with tin, zinc, and aluminum plating on carbon
steel; and (f) chemical etching and milling of aluminum." EPA has
defined electroplating broadly to include electroplating, electroless
plating, anodizing, coating (phosphating, chromating, and coloring),
chemical etching and milling, and printed circuit board manufacturing.
It is important to note that in addition to deleting the above-listed
plating operations from the definition of F006, EPA has also established
a separate group of waste codes for spent cyanide electroplating baths
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(F007, F008, and F009) and a separate waste code for the wastewater
treatment sludges from the electroplating operation referred to as
chemical conversion coating of aluminum (F019). Facilities are reminded
that today's proposal applies only to F006; it does not apply to F007,
F008, F009, and F019 or their treatment residuals. An example is a
treatment sludge generated from spent nickel cyanide plating solution (an
F007 wastewater). This bath solution is sent through cyanide destruction
and, for nickel removal, metal hydroxide precipitation. The precipitated
residual is F007 and not F006. EPA is currently studying these latter
codes and will develop treatment standards upon completion of these
studies.
Treatment standards are proposed for the nonwastewater and wastewater
forms of F006. For the nonwastewater form of F006 proposed treatment
standards are based on stabilization technology. For F006 wastewater,
the proposed treatment standard is "no land disposal." EPA believes that
any wastewater generated from dewatering of F006 waste can be recycled in
the wastewater treatment system and, therefore, a standard is not
needed. Furthermore, the wastewater generated during the dewatering of
F006 waste can also be discharged to POTWs or surface water if the
wastewater meets the applicable Federal, State, and local regulations.
The BOAT treatment standards, when promulgated, will represent
maximum acceptable concentrations in the TCLP leachate for selected
hazardous constituents in the waste or residuals from stabilization.
Proposed treatment standards are being established for cadmium, chromium,
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copper, lead, nickel, silver, and zinc, which were found to leach at
treatable levels from the untreated waste. If F006 wastes, as generated,
comply with the proposed BOAT treatment standards, then treatment is not
necessary as a prerequisite to land disposal.
The Agency intends to develop standards in the future for antimony,
arsenic, barium, selenium, and cyanide. EPA believes that these
contaminants are present in some untreated F006 wastes at treatable
levels. For these constituents, the Agency has not completed its studies
of treatment options. Therefore, EPA is reserving the proposal and
promulgation of treatment standards until that work is complete and the
data are available.
F006 waste is generated during a wide range of electroplating
operations. EPA has estimated that 4,500 facilities of this industry are
generating F006 waste during electroplating, electroless plating,
anodizing, coating {phosphating, chromating, and coloring), chemical
etching and milling, or printed circuit board manufacturing.
The standards proposed in the rule are established based on Toxicity
Characteristic Leaching Procedure (TCLP) analysis of the F006 waste. The
units for the leachate analysis are in mg/1 (parts per million on a
weight per volume basis). Testing procedures are specifically identified
in Appendix B (Analytical QA/QC) of this background document.
The following table presents the treatment standards for F006 waste.
For the purpose of applicability of the treatment standards, wastewaters
are defined as wastes containing less than 1 percent (weight basis)
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filterable solids and less than 1 percent (weight basis) total organic
carbon (TOC). Any F006 waste that does not meet this definition must
comply with treatment standards for F006 nonwastewaters.
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BOAT Treatment Standards for F006
(Nonwastewater)
Maximum for any single grab samele
Constituent
Antimony
Arsenic
Barium
Cadmium
Chromi urn
Copper
Lead
Nickel
Selenium
Silver
Zinc
Cyanide
Total composition
(mg/kg)
Not applicable
Not applicable
Not applicable
Not applicable
Not applicable
Not applicable
Not applicable
Not applicable
Not applicable
Not applicable
Not applicable
Reserved
TCLP
("9/1 )
Reserved
Reserved
Reserved
0.066
3.8
0.71
0.53
0.31
Reserved
0.26
0.086
Reserved
BOAT Treatment Standard for F006
(Wastewater)
No land disposal
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1. INTRODUCTION
This section of the background document presents a summary of the
legal authority pursuant to which the BOAT treatment standards were
developed, a summary of EPA's promulgated methodology for developing
BOAT, and finally a discussion of the petition process that should be
followed to request a variance from the BOAT treatment standards.
1.1 Legal Background
1.1.1 Requirements Under HSWA
The Hazardous and Solid Waste Amendments of 1984 (HSWA), which were
enacted on November 8, 1984, and which amended the Resource Conservation
and Recovery Act of 1976 (RCRA), impose substantial new responsibilities
on those who handle hazardous waste. In particular, the amendments
require the Agency to promulgate regulations that restrict the land
disposal of untreated hazardous wastes. In its enactment of HSWA,
Congress stated explicitly that "reliance on land disposal should be
minimized or eliminated, and land disposal, particularly landfill and
surface impoundment, should be the least favored method for managing
hazardous wastes" (RCRA section 1002(b)(7), 42 U.S.C. 6901(b)(7)).
One part of the amendments specifies dates on which particular groups
of untreated hazardous wastes will be prohibited from land disposal
unless "it has been demonstrated to the Administrator, to a reasonable
degree of certainty, that there will be no migration of hazardous
constituents from the disposal unit or injection zone for as long as the
wastes remain hazardous" (RCRA section 3004(d)(l), (e)(l), (g)(5);
42 U.S.C. 6924 (d)(l), (e)(l), (g)(5)).
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For the purpose of the restrictions, HSWA defines land disposal "to
include, but not be limited to, any placement of ... hazardous waste in
a landfill, surface impoundment, waste pile, injection well, land
treatment facility, salt dome formation, salt bed formation, or
underground mine or cave" (RCRA section 3004(k), 42 U.S.C. 6924(k)).
Although HSWA defines land disposal to include injection wells, such
disposal of solvents, dioxins, and certain other wastes, known as the
California List wastes, is covered on a separate schedule (RCRA section
3004(f)(2), 42 U.S.C. 6924 (f)(2)). This schedule requires that EPA
develop land disposal restrictions for deep well injection by
August 8, 1988.
The amendments also require the Agency to set "levels or methods of
treatment, if any, which substantially diminish the toxicity of the waste
or substantially reduce the likelihood of migration of hazardous
constituents from the waste so that short-term and long-term threats to
human health and the environment are minimized" (RCRA section 3004(m)(l),
42 U.S.C. 6924 (m)(l)). Wastes that meet treatment standards established
by EPA are not prohibited and may be land disposed. In setting treatment
standards for listed or characteristic wastes, EPA may establish
different standards for particular wastes within a single waste code with
differing treatability characteristics. One such characteristic is the
physical form of the waste. This frequently leads to different standards
for wastewaters and nonwastewaters.
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Alternatively, EPA can establish a treatment standard that is
applicable to more than one waste code when, in EPA's judgment, all the
waste can be treated to the same concentration. In those instances where
a generator can demonstrate that the standard promulgated for the
generator's waste cannot be achieved, the Agency also can grant a
variance from a treatment standard by revising the treatment standard for
that particular waste through rulemaking procedures. (A further
discussion of treatment variances is provided in Section 1.3.)
The land disposal restrictions are effective when promulgated unless
the Administrator grants a national variance and establishes a different
date (not to exceed 2 years beyond the statutory deadline) based on "the
earliest date on which adequate alternative treatment, recovery, or
disposal capacity which protects human health and the environment will be
available" (RCRA section 3004(h)(2), 42 U.S.C. 6924 (h)(2)).
If EPA fails to set a treatment standard by the statutory deadline
for any hazardous waste in the First Third or Second Third of the
schedule (see Section 1.1.2), the waste may not be disposed in a landfill
or surface impoundment unless the facility is in compliance with the
minimum technological requirements specified in section 3004(o) of RCRA.
In addition, prior to disposal, the generator must certify to the
Administrator that the availability of treatment capacity has been
investigated, and it has been determined that disposal in a landfill or
surface impoundment is the only practical alternative to treatment
currently available to the generator. This restriction on the use of
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landfills and surface impoundments applies until EPA sets a treatment
standard for the waste or until May 8, 1990, whichever is sooner. If the
Agency fails to set a treatment standard for any ranked hazardous waste
by May 8, 1990, the waste is automatically prohibited from land disposal
unless the waste is placed in a land disposal unit that is the subject of
a successful "no migration" demonstration (RCRA section 3004(g),
42 U.S.C. 6924(g)). "No migration" demonstrations are based on case-
specific petitions that show there will be no migration of hazardous
constituents from the unit for as long as the waste remains hazardous.
1.1.2 Schedule for Developing Restrictions
Under section 3004(g) of RCRA, EPA was required to establish a
schedule for developing treatment standards for all wastes that the
Agency had listed as hazardous by November 8, 1984. Section 3004(g)
required that this schedule consider the intrinsic hazards and volumes
associated with each of these wastes. The statute required EPA to set
treatment standards according to the following schedule:
1. Solvents and dioxins standards must be promulgated by
November 8, 1986;
2. The "California List" must be promulgated by July 8, 1987;
3. At least one-third of all listed hazardous wastes must be
promulgated by August 8, 1988 (First Third);
4. At least two-thirds of all listed hazardous wastes must be
promulgated by June 8, 1989 (Second Third); and
5. All remaining listed hazardous wastes and all hazardous wastes
identified as of November 8, 1984, by one or more of the
characteristics defined in 40 CFR Part 261 must be promulgated
by May 8, 1990 (Third Third).
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The statute specifically identified the solvent wastes as those
covered under waste codes F001, F002, F003, F004, and F005; it identified
the dioxin-containing hazardous wastes as those covered under waste codes
F020, F021, F022, and F023.
Wastes collectively known as the California List wastes, defined
under section 3004(d) of HSWA, are liquid hazardous wastes containing
metals, free cyanides, PCBs, corrosives (i.e., a pH less than or equal to
2.0), and any liquid or nonliquid hazardous waste containing halogenated
organic compounds (HOCs) above 0.1 percent by weight. Rules for the
California List were proposed on December 11, 1986, and final rules for
PCBs, corrosives, and HOC-containing wastes were established
August 12, 1987. In that rule, EPA elected not to establish standards
for metals. Therefore, the statutory limits became effective.
On May 28, 1986, EPA published a final rule (51 FR 19300) that
delineated the specific waste codes that would be addressed by the First
Third, Second Third, and Third Third. This schedule is incorporated into
40 CFR 268.10, 268.11, and 268.12.
1.2 Summary of Promulgated BOAT Methodology
In a November 7, 1986, rulemaking, EPA promulgated a technology-based
approach to establishing treatment standards under section 3004(m).
Section 3004(m) also specifies that treatment standards must "minimize"
long- and short-term threats to human health and the environment arising
from land disposal of hazardous wastes.
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Congress Indicated in the legislative history accompanying the HSWA
that "[t]he requisite levels of [sic] methods of treatment established by
the Agency should be the best that has been demonstrated to be
achievable," noting that the intent is "to require utilization of
available technology" and not a "process which contemplates
technology-foreing standards" (Vol. 130 Cong. Rec. S9178 (daily ed.,
July 25, 1984)). EPA has interpreted this legislative history as
suggesting that Congress considered the requirement under section 3004(m)
to be met by application of the best demonstrated and achievable (i.e.,
available) technology prior to land disposal of wastes or treatment
residuals. Accordingly, EPA's treatment standards are generally based on
the performance of the best demonstrated available technology (BOAT)
identified for treatment of the hazardous constituents. This approach
involves the identification of potential treatment systems, the
determination of whether they are demonstrated and available, and the
collection of treatment data from well-designed and well-operated systems.
The treatment standards, according to the statute, can represent
levels or methods of treatment, if any, that substantially diminish the
toxicity of the waste or substantially reduce the likelihood of migration
of hazardous constituents. Wherever possible, the Agency prefers to
establish BOAT treatment standards as "levels" of treatment
(i.e., performance standards), rather than adopting an approach that
would require the use of specific treatment "methods." EPA believes that
concentration-based treatment levels offer the regulated community greater
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flexibility to develop and implement compliance strategies, as well as an
incentive to develop innovative technologies.
1.2.1 Waste Treatability Group
In developing the treatment standards, EPA first characterizes the
waste(s). As necessary, EPA may establish treatability groups for wastes
having similar physical and chemical properties. That is, if EPA
believes that wastes represented by different waste codes could be
treated to similar concentrations using identical technologies, the
Agency combines the codes into one treatability group. EPA generally
considers wastes to be similar when they are both generated from the same
industry and from similar processing stages. In addition, EPA may
combine two or more separate wastes into the same treatability group when
data are available showing that the waste characteristics affecting
performance are similar or that one waste would be expected to be less
difficult to treat.
Once the treatability groups have been established, EPA collects and
analyzes data on identified technologies used to treat the wastes in each
treatability group. The technologies evaluated must be demonstrated on
the waste or a similar waste and must be available for use.
1.2.2 Demonstrated and Available Treatment Technologies
Consistent with legislative history, EPA considers demonstrated
technologies to be those that are used to treat the waste of interest or
a similar waste with regard to parameters that affect treatment selection
(see November 7, 1986, 51 PR 40588). EPA also will consider as treatment
those technologies used to separate or otherwise process chemicals and
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other materials. Some of these technologies clearly are applicable to
waste treatment, since the wastes are similar to raw materials processed
in industrial applications.
For most of the waste treatability groups for which EPA will
promulgate treatment standards, EPA will identify demonstrated
technologies either through review of literature related to current waste
treatment practices or on the basis of information provided by specific
facilities currently treating the waste or similar wastes.
In cases where the Agency does not identify any facilities treating
wastes represented by a particular waste treatability group, EPA may
transfer a finding of demonstrated treatment. To do this, EPA will
compare the parameters affecting treatment selection for the waste
treatability group of interest to other wastes for which demonstrated
technologies already have been determined. The parameters affecting
treatment selection and their use for this waste are described in
Section 3.2 of this document. If the parameters affecting treatment
selection are similar, then the Agency will consider the treatment
technology also to be demonstrated for the waste of interest. For
example, EPA considers rotary kiln incineration to be a demonstrated
technology for many waste codes containing hazardous organic
constituents, high total organic content, and high filterable solids
content, regardless of whether any facility is currently treating these
wastes. The basis for this determination is data found in literature and
data generated by EPA confirming the use of rotary kiln incineration on
wastes having the above characteristics.
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If no commercial treatment or recovery operations are identified for
a waste or wastes with similar physical or chemical characteristics that
affect treatment selection, the Agency will be unable to identify any
demonstrated treatment technologies for the waste, and, accordingly, the
waste will be prohibited from land disposal (unless handled in accordance
with the exemption and variance provisions of the rule). The Agency is,
however, committed to establishing treatment standards as soon as new or
improved treatment processes are demonstrated (and available).
Operations available only at research facilities, pilot- and bench-
scale operations, will not be considered in identifying demonstrated
treatment technologies for a waste because these technologies would not
necessarily be "demonstrated." Nevertheless, EPA may use data generated
at research facilities in assessing the performance of demonstrated
technologies.
As discussed earlier, Congress intended that technologies used to
establish treatment standards under section 3004(m) be not only
"demonstrated," but also available. To decide whether demonstrated
technologies may be considered "available," the Agency determines whether
they (1) are commercially available and (2) substantially diminish the
toxicity of the waste or substantially reduce the likelihood of migration
of hazardous constituents from the waste.
EPA will only set treatment standards based on a technology that
meets the above criteria. Thus, the decision to classify a technology as
"unavailable" will have a direct impact on the treatment standard. If
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the best technology is unavailable, the treatment standard will be based
on the next best treatment technology determined to be available. To the
extent that the resulting treatment standards are less stringent, greater
concentrations of hazardous constituents in the treatment residuals could
be placed in land disposal units.
There also may be circumstances in which EPA concludes that for a
given waste none of the demonstrated treatment technologies are
"available" for purposes of establishing the Section 3004(m) treatment
performance standards. Subsequently, these wastes will be prohibited
from continued placement in or on the land unless managed in accordance
with applicable exemptions and variance provisions. The Agency is,
however, committed to establishing new treatment standards as soon as new
or improved treatment processes become "available."
(1) Proprietary or patented processes. If the demonstrated
treatment technology is a proprietary or patented process that is not
generally available, EPA will not consider the technology in its
determination of the treatment standards. EPA will consider a
proprietary or patented process available if it determines that the
treatment method can be purchased or licensed from the proprietor or is a
commercially available treatment. The services of the commercial
facility offering this technology often can be purchased even if the
technology itself cannot be purchased.
(2) Substantial treatment. To be considered "available," a
demonstrated treatment technology must "substantially diminish the
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toxicity" of the waste or "substantially reduce the likelihood of
migration of hazardous constituents" from the waste in accordance with
section 3004(m). By requiring that substantial treatment be achieved in
order to set a treatment standard, the statute ensures that all wastes
are adequately treated before being placed in or on the land and ensures
that the Agency does not require a treatment method that provides little
or no environmental benefit. Treatment will always be deemed substantial
if it results in nondetectable levels of the hazardous constituents of
concern. If nondetectable levels are not achieved, then a determination
of substantial treatment will be made on a case-by-case basis. This
approach is necessary because of the difficulty of establishing a
meaningful guideline that can be applied broadly to the many wastes and
technologies to be considered. EPA will consider the following factors
in an effort to evaluate whether a technology provides substantial
treatment on a case-by-case basis:
Number and types of constituents treated;
Performance (concentration of the constituents in the
treatment residuals); and
Percent of constituents removed.
If none of the demonstrated treatment technologies achieve
substantial treatment of a waste, the Agency cannot establish treatment
standards for the constituents of concern in that waste.
1.2.3 Collection of Performance Data
Performance data on the demonstrated available technologies are
evaluated by the Agency to determine whether the data are representative
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of well-designed and well-operated treatment systems. Only data from
well-designed and well-operated systems are Included In determining
BOAT. The data evaluation includes data already collected directly by
EPA and/or data provided by industry. In those instances where
additional data are needed to supplement existing information, EPA
collects additional data through a sampling and analysis program. The
principal elements of this data collection program are: (1) identifi-
cation of facilities for site visits, (2) an engineering site visit,
(3) a Sampling and Analysis Plan, (4) a sampling visit, and (5) an Onsite
Engineering Report.
(1) Identification of facilities for site visits. To identify
facilities that generate and/or treat the waste of concern, EPA uses a
number of information sources. These include Stanford Research
Institute's Directory of Chemical Producers; EPA's Hazardous Waste Data
Management System (HWDMS); the 1986 Treatment, Storage, Disposal Facility
(TSDF) National Screening Survey; and EPA's Industry Studies Data Base.
In addition, EPA contacts trade associations to inform them that the
Agency is considering visits to facilities in their industry and to
solicit their assistance in identifying facilities for EPA to consider in
its treatment sampling program.
After identifying facilities that treat the waste, EPA uses this
hierarchy to select sites for engineering visits: (1) generators treating
single wastes on site; (2) generators treating multiple wastes together
on site; (3) commercial treatment, storage, and disposal facilities
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(TSDFs); and (4) EPA in-house treatment. This hierarchy is based on two
concepts: (1) to the extent possible, EPA should develop treatment
standards from data produced by treatment facilities handling only a
single waste, and (2) facilities that routinely treat a specific waste
have had the best opportunity to optimize design parameters. Although
excellent treatment can occur at many facilities that are not high in
this hierarchy, EPA has adopted this approach to avoid, when possible,
ambiguities related to the mixing of wastes before and during treatment.
When possible, the Agency will evaluate treatment technologies using
commercially operated systems. If performance data from properly
designed and operated commercial treatment methods for a particular waste
or a waste judged to be similar are not available, EPA may use data from
research facilities operations. Whenever research facility data are
used, EPA will explain in the preamble and background document why such
data were used and will request comments on the use of such data.
Although EPA's data bases provide information on treatment for
individual wastes, the data bases rarely provide data that support the
selection of one facility for sampling over another. In cases where
several treatment sites appear to fall into the same level of the
hierarchy, EPA selects sites for visits strictly on the basis of which
facility could most expeditiously be visited and later sampled if
justified by the engineering visit.
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(2) Engineering site visit. Once a treatment facility has been
selected, an engineering site visit is made to confirm that a candidate
for sampling meets EPA's criteria for a well-designed facility and to
ensure that the necessary sampling points can be accessed to determine
operating parameters and treatment effectiveness. During the visit, EPA
also confirms that the facility appears to be well operated, although the
actual operation of the treatment system during sampling is the basis for
EPA's decisions regarding proper operation of the treatment unit. In
general, the Agency considers a well-designed facility to be one that
contains the unit operations necessary to treat the various hazardous
constituents of the waste, as well as to control other nonhazardous
materials in the waste that may affect treatment performance.
In addition to ensuring that a system is reasonably well designed,
the engineering visit examines whether the facility has a way to measure
the operating parameters that affect performance of the treatment system
during the waste treatment period. For example, EPA may choose not to
sample a treatment system that operates in a continuous mode, for which
an important operating parameter cannot be continuously recorded. In
such systems, instrumentation is important in determining whether the
treatment system is operating at design values during the waste treatment
period.
(3) Sampling and Analysis Plan. If after the engineering site visit
the Agency decides to sample a particular plant, the Agency will then
develop a site-specific Sampling and Analysis Plan (SAP) according to the
Generic Quality Assurance Project Plan for the Land Disposal Restriction
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Program ("BOAT"), EPA/530-SW-87-011. In brief, the SAP discusses where
the Agency plans to sample, how the samples will be taken, the frequency
of sampling, the constituents to be analyzed and the method of analysis,
operational parameters to be obtained, and specific laboratory quality
control checks on the analytical results.
The Agency will generally produce a draft of the site-specific
Sampling and Analysis Plan within 2 to 3 weeks of the engineering visit.
The draft of the SAP is then sent to the plant for review and comment.
With few exceptions, the draft SAP should be a confirmation of data
collection activities discussed with the plant personnel during the
engineering site visit. EPA encourages plant personnel to recommend any
modifications to the SAP that they believe will improve the quality of
the data.
It is important to note that sampling of a plant by EPA does not mean
that the data will be used in the development of treatment standards for
BOAT. EPA's final decision on whether to use data from a sampled plant
depends on the actual analysis of the waste being treated and on the
operating conditions at the time of sampling. Although EPA would not
plan to sample a facility that was not ostensibly well designed and well
operated, there is no way to ensure that at the time of the sampling the
facility will not experience operating problems. Additionally, EPA
statistically compares its test data to suitable industry-provided data,
where available, in its determination of what data to use in developing
treatment standards. The methodology for comparing data is presented
later in this section.
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(NOTE: Facilities wishing to submit data for consideration in the
development of BOAT standards should, to the extent possible, provide
sampling information similar to that acquired by EPA. Such facilities
should review the Generic Quality Assurance Project Plan for the Land
Disposal Restriction Program ("BOAT"), which delineates all of the
quality control and quality assurance measures associated with sampling
and analysis. (Quality assurance and quality control procedures are
summarized in Section 1.2.6 of this document.))
(4) Sampling visit. The purpose of the sampling visit is to collect
samples that characterize the performance of the treatment system and to
document the operating conditions that existed during the waste treatment
period. At a minimum, the Agency attempts to collect sufficient samples
of the untreated waste and solid and liquid treatment residuals so that
variability in the treatment process can be accounted for in the
development of the treatment standards. To the extent practicable, and
within safety constraints, EPA or its contractors collect all samples and
ensure that chain-of-custody procedures are conducted so that the
integrity of the data is maintained.
In general, the samples collected during the sampling visit will have
already been specified in the SAP. In some instances, however, EPA will
not be able to collect all planned samples because of changes in the
facility operation or plant upsets; EPA will explain any such deviations
from the SAP in its follow-up Onsite Engineering Report.
16
-------
(5) Onsite Engineering Report. EPA summarizes all its data
collection activities and associated analytical results for testing at a
facility in a report referred to as the Onsite Engineering Report (OER).
This report characterizes the waste(s) treated, the treated residual
concentrations, the design and operating data, and all analytical results
including methods used and accuracy results. This report also describes
any deviations from EPA's suggested analytical methods for hazardous
wastes (see Test Methods for Evaluating Solid Waste. SW-846, Third
Edition, November 1986).
After the Onsite Engineering Report is completed, the report is
submitted to the plant for review. This review provides the plant with a
final opportunity to claim any information contained in the report as
confidential. Following the review and incorporation of comments, as
appropriate, the report is made available to the public with the
exception of any material claimed as confidential by the plant.
1.2.4 Hazardous Constituents Considered and Selected for Regulation
(1) Development of BDAT list. The list of hazardous constituents
within the waste codes that are targeted for treatment is referred to by
the Agency as the BDAT constituent list. This list, provided as
Table 1-1, is derived from the constituents presented in 40 CFR Part 261,
Appendices VII and VIII, as well as several ignitable constituents used
as the basis of listing wastes as F003 and F005. These sources provide a
comprehensive list of hazardous constituents specifically regulated under
RCRA. The BDAT list consists of those constituents that can be analyzed
using methods published in SW-846, Third Edition.
17
-------
1521g
Taule 1-1 BOAT Constituent list
BOAT
reference
no.
222.
1.
2.
3.
4.
5.
6.
223.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
25.
26.
27.
28.
29.
224.
225.
226.
30.
227.
31.
214.
32.
Parameter
Volatiles
Acetone
Acetonitn le
Acrolein
Aery Ion itrile
Benzene
Bromodichloromethane
Bromomethane
n-Butyl alcohol
Carbon tetrachloride
Carbon chsulfide
Chlorobenzene
2-Chloro-l ,3-butadiene
Ch lorod i bromomethane
Chloroethane
2-Chloroethyl vinyl ether
Chloroform
Chloromethane
3-Chloropropene
1.2-Dibromo-3-ch1oropropane
1,2-Dibromoethane
Di bromomethane
Trans-1.4-Oichloro-2-butene
Dich lorod if luoromethane
1 . 1 -0 i ch 1 oroethane
1 ,2-Oichloroethane
1 . 1-0 ich loroethy lene
Trans-1.2-D1chloroethene
1,2-Oichloropropane
Trans-1.3-0ichloropropene
cis-1.3-Dichloropropene
1.4-Oioxane
2-Ethoxyethanol
Ethyl acetate
Etnyl benzene
Ethyl cyanide
Ethyl ether
Ethyl met hacry late
Etny'ene oxide
lodometnane
CAS no.
67-64-1
75-05-8
107-02-8
107-13-1
71-43-2
75-27-4
74-83-9
71-36-3
56-23-5
75-15-0
lOfl-dO-7
126-99-8
124-48-1
75-00-3
110-75-8
67-66-3
74-87-3
107-05-1
96-12-8
106-93-4
74-95-3
110-57-6
75-71-8
75-34-3
107-06-2
75-35-4
156-60-5
78-87-5
10061-02-6
10061-01-5
123-91-1
110-80-5
141-78-6
100-41-4
107-12-0
60-29-7
97-63-2
75-21-8
74-88-4
18
-------
1521g
Table 1-1 (continued)
BOAT
reference
no
33.
228.
34.
229.
35.
37.
38.
230.
39.
40.
41.
42.
43.
44.
45.
46.
47.
48.
49.
231.
50.
215.
216.
217.
51.
52.
53.
54.
55.
56.
57.
58.
59.
21H.
60.
61.
62.
Parameter
Volatiles (continued)
Isobutyl alcohol
Methane 1
Methyl ethyl ketone
Methyl isobutyl ketone
Methyl met hacry late
Methacrylonitn le
Methylene chloride
2-Nitropropane
Pyridine
1,1.1. 2-Tetrachloroethane
1 . 1 .2. 2-Tetrachloroethane
Tetrachloroethene
Toluene
Tribromomethane
1.1, 1-Tr Khloroethane
1,1.2-Trichloroethane
Trichloroethene
Trichloromonof luoromethane
1,2,3-Tnchloropropane
l,l,2-Tnchloro-l,2.2-trif luoro-
ethane
Vinyl chloride
1,2-Xylene
1.3-Xylene
1.4-Xylene
Semivolat i les
Acenaphthalene
Acenaphthene
Acetophenone
2 - Acety 1am i nof 1 uorene
4-Aminobiphenyl
Am line
Anthracene
Aramite
Benz(a)anthracene
Benzal chloride
Benzenethiol
Deleted
6enzc( j Jpvrene
CAS no.
73-83-1
67-56-1
78-93-3
108-10-1
80-62-6
126-98-7
75-09-2
79-46-9
110-86-1
630-20-6
79-34-6
127-18-4
108-88-3
75-25-2
71-55-6
79-00-5
79-01-6
75-69-4
96-1B-4
76-13-1
75-01-4
97-47-6
108-38-3
106-44-5
208-96-8
33-32-9
96-86-2
53-96-3
92-67-1
62-53-3
120-12-7
UO-57-8
55-55-3
?a-tf7-3
10B-98-5
50-32-3
-------
ISZlg
Table 1-1 (continued)
BOAT
reference
no.
53.
64.
65.
66.
67.
68.
69.
70.
71.
72.
73.
74.
75.
76.
77.
78.
79.
80.
81.
82.
232.
83.
84.
85.
86.
87.
88.
89.
90.
91.
92.
93.
94.
95. J
95.
97.
98.
i-9.
100.
101.
Parameter
Semivolnt i les (continued)
6enzo(b)f luorantnene
8enzo(ghi )perylene
Benzo(k)f luorantnene
p-Benzoquinone
B i s( 2-ch loroethoxy Imethane
Bis(2-chloroethyl)ether
Bis(2-chloroisopropyl)ether
Bis(2-ethylnexyl)phthalate
4-Bromophenyl phenyl ether
Butyl benzyl phthalate
2-sec-Buty 1 -4 , 6-d i n i tropheno 1
p-Chloroani line
Chlorobenzilate
p-Ch loro-m-creso 1
2-Ch loronaphtha lene
2-Chlorophenol
3-Chloropropionitri le
Chrysene
ortno-Cresol
para-Cresol
Cyclohexanone
0 i benz ( a , h ) anthracene
Oibenzo(a,e)pyrene
Dibenzola. Opyrene
m-Oichlorobenzene
o-Dichlorobenzene
p-0 ich lorooenzene
3.3'-Oichlorobenzidine
2.4-Dichlorophenol
2,6-Dichlorophenol
Oiethyl phthalate
3 , 3 ' -0 imethoxybenz id i ne
p-Dimethylaminoazobenzene
3,3'-Oimethylbenzidine
2,4-Dimethylphenol
Dimethyl phthalate
Oi-n-butyl phthalate
i ; 4-0 1 n it rodenzene
4,6-Dimtro-o-cresol
2.4-Oinitrophenol
CAS no.
205-99-2
191-24-2
207-08-9
106-51-4
111-91-1
111-44-4
39638-32-9
117-81-7
101-55-3
85-68-7
68-85-7
106-47-8
510-15-6
59-50-7
91-58-7
95-57-8
542-76-7
218-01-9
95-48-7
106-44-5
108-94-1
53-70-3
192-65-4
189-55-9
541-73-1
95-50-1
106-46-7
91-94-1
120-83-2
H7-65-0
64-66-2
119-90-4
60-11-7
119-93-7
105-67-9
131-11-3
84-74-2
100-25-4
534-52-1
51-28-5
20
-------
I521g
Taole 1-1 (continued)
BOAT
reference
no.
102.
103.
104.
105..
106.
219.
107.
108.
109.
no.
111.
112.
113.
114.
115.
116.
117.
118.
119.
120.
36.
121.
122.
123.
124.
125.
126.
127.
128.
129.
130.
131.
132.
133.
134.
135.
136.
137.
138.
Parameter
Semivolat i les (continued)
2,4-Dinitrotoluene
2,6-Dinurotoluene
Di-n-octyl pnthalate
Di-n-propylnitrosannne
Dipheny lamine
0 1 pheny 1 n i t rosam i ne
1 . 2-D i pheny Ihydraz i ne
Fluoranthene
Fluorene
Hexach 1 orobenzene
Hexach lorobutad iene
Hexach lorocyclopentadiene
Hexacn loroetnane
Hexach lorophene
Hexach loropropene
Indeno( 1,2, 3-cd)pyrene
Isosafrole
Methapyri Iene
3-Methylcholanthrene
4.4'-Methylenebis
(2-cnloroaniline)
Methyl methanesulfonate
Naphthalene
1.4-Naphthoquinone
1-Naphthy lamine
2-Naphthy lamine
p-Nitroani line
Nitrobenzene
4-Nitrophenol
N-Nitrosodi-n-butylamine
N-Nitrosodiethylamine
N-Nitrosodimethy lamine
N-Nitrosomethylethylamine
N-N 1 1 rosomorpho 1 1 ne
N-Nitrosopiperidine
n-Nitrosopyrrol idine
5-Nitro-o-toluioine
Pemacn lorobenzene
Pentacn loroetnane
Pentachloronttrobenzene
CAS no.
121-14-2
606-20-2
117-84-0
621-64-7
122-39-4
86-30-6
122-56-7
206-44-0
86-73-7
118-74-1
87-68-3
77-47-4
67-72-1
70-30-4
1388-71-7
193-39-5
120-58-1
91-80-5
56-49-5
101-14-4
66-27-3
91-20-3
130-15-4
134-32-7
91-59-8
100-01-6
98-95-3
100-02-7
324-16-3
55-18-5
62-75-9
10595-95-6
59-89-2
100-75-4
930-55-2
99-65-b
608-93-5
76-01-7
82-66-3
21
-------
1521g
Table 1-1 (continued)
BOAT
reference
no.
139.
140.
141.
142.
220.
143.
144.
145.
146.
147.
148.
149.
150.
151.
152.
153.
154.
155.
156.
157.
158.
159.
221.
160.
161.
162.
163.
164.
165.
166.
167.
168.
159.
170.
171.
Parameter
Semivolat i les (continued)
Pentacnlorophenol
Phenacetin
Phenanthrene
Phenol
Phthalic anhydride
2-Picoline
Pronamide
Pyrene
Resorcinol
Safrole
1 , 2 . 4 . 5- Tet rach lorobenzene
2 . 3 . 4 , 6-Tet rach loropheno 1
1 ,2.4-Trichlorobenzene
2, 4. 5-Trich loropheno 1
2. 4. 6-Trlch loropheno 1
Tr i s ( 2 . 3-d i bromopropy 1 )
phosphate
Metals
Ant imony
Arsenic
Barium
Beryllium
Cadmium
Chromium (total)
Chromium (hexavalent)
Copper
Lead
Mercury
Nickel
Selenium
Silver
Thallium
Vanadium
Zinc
Inorganics
Cyanide
Fluoride
Sulf ide
CAS no.
87-86-5
62-44-2
85-01-8
108-95-2
85-44-9
109-06-8
23950-58-5
129-00-0
108-46-3
94-59-7
95-94-3
58-90-2
120-82-1
95-95-4
88-06-2
126-72-7
7440-36-0
7440-38-2
7440-39-3
7440-41-7
7440-43-9
7440-47-32
-
7440-50-8
7439-92-1
7439-97-6
7440-02-0
7782-49-2
7440-22-4
7440-28-0
7440-62-2
7440-66-6
57-12-5
16964-48-8
8496-35-8
22
-------
1521g
Table 1-1 (continued)
BOAT
reference
no.
172.
173.
174.
175.
176.
177.
178.
179.
180.
181.
182.
183.
184.
185.
186.
187.
188.
189.
190.
191.
192.
193.
194.
195.
196.
197.
198.
199.
200.
201.
202.
Parameter
Orqanochlorine pesticides
Aldrin
alpha-BHC
beta-BHC
delta-BHC
gamma-8HC
Chlordane
000
DOE
DDT
Dieldrin
Endosulfan I
Endosulfan 11
Endnn
Endrin aldehyde
Heptachlor
Heptachlor epoxide
Isodrin
Kepone
Methoxyc lor
Toxaphene
Phenoxvacet ic acid herbicides
2,4-Oichlorophenoxyacet ic acid
Silvex
2.4.5-T
Oraanonhosohorous insecticides
Disulfoton
Famphur
Methyl parathion
Parathion
Phorate
PCBs
Aroclor 1016
Aroclor 1221
Aroclor 1232
CAS no.
309-00-2
319-84-6
319-85-7
319-86-8
58-89-9
57-74-9
72-54-8
72-55-9
50-29-3
60-57-1
939-98-8
33213-6-5
72-20-8
7421-93-4
76-44-8
1024-57-3
465-73-6
143-50-0
72-43-5
8001-35-2
94-75-7
93-72-1
93-76-5
298-04-4
52-H5-7
296-00-0
56-38-2
298-02-2
12674-11-2
11104-ZS-2
11141-15-5
-------
1521g
Table 1-1 (continued)
BOAT
reference Parameter CAS no.
no.
PCBs (continued!
303. Aroclor 1242 53469-21-9
204. Aroclor 1248 12672-29-6
205. Aroclor 1254 11097-69-1
206. Aroclor 1260 11096-82-5
Oioxins and furans
207. Hexachlorodibenzo-p-dioxins
208. Hexachlorodibenzofurans
209. Pentachlorodibenzo-p-dioxins
210. Pentachlorodibenzofurans
211. Tetrachlorodibenzo-p-dioxins
212. Tetrachlorodibenzofurans
213. 2.3,7.B-Tetrachlorodibenzo-p-dioxin 1746-01-6
-------
The initial BOAT constituent list was published in EPA's Generic
Quality Assurance Project Plan for the Land Disposal Restriction Program
(BOAT), March 1987 (EPA/530-SW-87-011). Additional constituents will be
added to the BOAT constituent list as more key constituents are
identified for specific waste codes or as new analytical methods are
developed for hazardous constituents. For example, since the list was
published in March 1987, 18 additional constituents (hexavalent chromium,
xylenes (all three isomers), benzal chloride, phthalic anhydride,
ethylene oxide, acetone, n-butyl alcohol, 2-ethoxyethanol, ethyl acetate,
ethyl benzene, ethyl ether, methanol, methyl isobutyl ketone,
2-nitropropane, l,l,2-trichloro-l,2,2-
trifluoroethane, and cyclohexanone) have been added to the list.
Chemicals are listed in Appendix VIII if they are shown in scientific
studies to have toxic, carcinogenic, mutagenic, or teratogenic effects on
humans or other life-forms, and they include such substances as those
identified by the Agency's Carcinogen Assessment Group as being
carcinogenic. Including a constituent in Appendix VIII means that the
constituent can be cited as a basis for listing toxic wastes.
Although Appendix VII, Appendix VIII, and the F003 and F005
ignitables provide a comprehensive list of RCRA-regulated hazardous
constituents, not all of the constituents can be analyzed in a complex
waste matrix. Therefore, constituents that could not be readily analyzed
in an unknown waste matrix were not included on the initial BOAT list.
As mentioned above, however, the BOAT constituent list is a continuously
25
-------
growing list that does not preclude the addition of new constituents when
analytical methods are developed.
There are five major reasons that constituents were not included on
the BOAT constituent list:
1. Constituents are unstable. Based on their chemical structure,
some constituents will either decompose in water or will
ionize. For example, maleic anhydride will form maleic acid
when it comes in contact with water and copper cyanide will
ionize to form copper and cyanide ions. However, EPA may choose
to regulate the decomposition or ionization products.
2. EPA-approved or verified analytical methods are not available.
Many constituents, such as 1,3,5-trinitrobenzene, are not
measured adequately or even detected using any of EPA's
analytical methods published in SW-846 Third Edition.
3. The constituent is a member of a chemical group designated in
Appendix VIII as not otherwise specified (N.O.S.). Constituents
listed as N.O.S., such as chlorinated phenols, are a generic
group of some types of chemicals for which a single analytical
procedure is not available. The individual members of each such
group need to be listed to determine whether the constituents
can be analyzed. For each N.O.S. group, all those constituents
that can be readily analyzed are included in the BOAT
constituent list.
4. Available analytical procedures are not appropriate for a
complex waste matrix. Some compounds, such as auramine, can be
analyzed as a pure constituent. However, in the presence of
other constituents, the recommended analytical method does not
positively identify the constituent. The use of high pressure
liquid chromatography (HPLC) presupposes a high expectation of
finding the specific constituents of interest. In using this
procedure to screen samples, protocols would have to be
developed on a case-specific basis to verify the identity of
constituents present in the samples. Therefore, HPLC is not an
appropriate analytical procedure for complex samples containing
unknown constituents.
5. Standards for analytical instrument calibration are not
commercially available. For several constituents, such as
benz(c)acridine, commercially available standards of a
"reasonably" pure grade are not available. The unavailability
of a standard was determined by a review of catalogs from
specialty chemical manufacturers.
26
-------
Two constituents (fluoride and sulfide) are not specifically included
in Appendices VII and VIII; however, these compounds are included on the
BOAT list as indicator constituents for compounds from Appendices VII and
VIII such as hydrogen fluoride and hydrogen sulfide, which ionize in
water.
The BOAT constituent list presented in Table 1-1 is divided into the
following nine groups:
Volatile organics;
Semi volatile organics;
Metals;
Other inorganics;
Organochlorine pesticides;
Phenoxyacetic acid herbicides;
Organophosphorous insecticides;
PCBs; and
Dioxins and furans.
The constituents were placed in these categories based on their chemical
properties. The constituents in each group are expected to behave
similarly during treatment and are also analyzed, with the exception of
the metals and inorganics, by using the same analytical methods.
(2) Constituent selection analysis. The constituents that the
Agency selects for regulation in each treatability group are, in general,
those found in the untreated wastes at treatable concentrations. For
certain waste codes, the target list for the untreated waste may have
been shortened (relative to analyses performed to test treatment
27
-------
technologies) because of the extreme unlikelihood that the constituent
will be present.
In selecting constituents for regulation, the first step is to
summarize all the constituents that were found in the untreated waste at
treatable concentrations. This process involves the use of the
statistical analysis of variance (ANOVA) test, described in Section
1.2.6, to determine if constituent reductions were significant. The
Agency interprets a significant reduction in concentration as evidence
that the technology actually "treats" the waste.
There are some instances where EPA may regulate constituents that are
not found in the untreated waste but are detected in the treated
residual. This is generally the case where presence of the constituents
in the untreated waste interferes with the quantification of the
constituent of concern. In such instances, the detection levels of the
constituent are relatively high, resulting in a finding of "not detected"
when, in fact, the constituent is present in the waste.
After determining which of the constituents in the untreated waste
are present at treatable concentrations, EPA develops a list of potential
constituents for regulation. The Agency then reviews this list to
determine if any of these constituents can be excluded from regulation
because they would be controlled by regulation of other constituents in
the list.
EPA performs this indicator analysis for two reasons: (1) it reduces
the analytical cost burdens on the treater and (2) it facilitates
implementation of the compliance and enforcement program. EPA's
28
-------
rationale for selection of regulated constituents for this waste code is
presented in Section 5 of this background document.
(3) Calculation of standards. The final step in the calculation of
the BOAT treatment standard is the multiplication of the average
treatment value by a factor referred to by the Agency as the variability
factor. This calculation takes into account that even well-designed and
well-operated treatment systems will experience some fluctuations in
performance. EPA expects that fluctuations will result from inherent
mechanical limitations in treatment control systems, collection of
treated samples, and analysis of these samples. All of the above
fluctuations can be expected to occur at well-designed and well-operated
treatment facilities. Therefore, setting treatment standards utilizing a
variability factor should be viewed not as a relaxing of section 3004(m)
requirements, but rather as a function of the normal variability of the
treatment processes. A treatment facility will have to be designed to
meet the mean achievable treatment performance level to ensure that the
performance levels remain within the limits of the treatment standard.
The Agency calculates a variability factor for each constituent of
concern within a waste treatability group using the statistical
calculation presented in Appendix A. The equation for calculating the
variability factor is the same as that used by EPA for the development of
numerous regulations in the Effluent Guidelines Program under the Clean
Water Act. The variability factor establishes the instantaneous maximum
based on the 99th percentile value.
There is an additional step in the calculation of the treatment
standards in those instances where the ANOVA analysis shows that more
29
-------
than one technology achieves a level of performance that represents
BOAT. In such instances, the BOAT treatment standard is calculated by
first averaging the mean performance value for each technology for each
constituent of concern and then multiplying that value by the highest
variability factor among the technologies considered. This procedure
ensures that all the BOAT technologies used as the basis for the
standards will achieve full compliance.
1.2.5 Compliance with Performance Standards
All the treatment standards reflect performance achieved by the best
demonstrated available technology (BOAT). As such, compliance with these
standards requires only that the treatment level be achieved prior to
land disposal. It does not require the use of any particular treatment
technology. While dilution of the waste as a means to comply with the
standard is prohibited, wastes that are generated in such a way as to
naturally meet the standard can be land disposed without treatment. With
the exception of treatment standards that prohibit land disposal, all
treatment standards proposed are expressed as a concentration level.
EPA has used both total constituent concentration and TCLP analyses
of the treated waste as a measure of technology performance. EPA's
rationale for when each of these analytical tests is used is explained in
the following discussion.
For all organic constituents, EPA is basing the treatment standards
on the total constituent concentration found in the treated waste. EPA
based its decision on the fact that technologies exist to destroy the
30
-------
various organics compounds. Accordingly, the best measure of performance
would be the extent to which the various organic compounds have been
destroyed or the total amount of constituent remaining after treatment.
(NOTE: EPA's land disposal restrictions for solvent waste codes
F001-F005 (51 FR 40572) use the TCLP value as a measure of performance.
At the time that EPA promulgated the treatment standards for F001-F005,
useful data were not available on total constituent concentrations in
treated residuals and, as a result, the TCLP data were considered to be
the best measure of performance.)
For all metal constituents, EPA is using both total constituent
concentration and/or the TCLP as the basis for treatment standards. The
total constituent concentration is being used when the technology basis
includes a metal recovery operation. The underlying principle of metal
recovery is the reduction of the amount of metal in a waste by separating
the metal for recovery; therefore, total constituent concentration in the
treated residual is an important measure of performance for this
technology. Additionally, EPA also believes that it is important that
any remaining metal in a treated residual waste not be in a state that is
easily Teachable; accordingly, EPA is also using the TCLP as a measure of
performance. It is important to note that for wastes for which treatment
standards are based on a metal recovery process, the facility has to
comply with both the total constituent concentration and the TCLP prior
to land disposal.
31
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In cases where treatment standards for metals are not based on
recovery techniques but rather on stabilization, EPA is using only the
TCLP as a measure of performance. The Agency's rationale is that
stabilization is not meant to reduce the concentration of metal in a
waste but only to chemically minimize the ability of the metal to leach.
1.2.6 Identification of BOAT
(1) Screening of treatment data. This section explains how the
Agency determines which of the treatment technologies represent treatment
by BOAT. The first activity is to screen the treatment performance data
from each of the demonstrated and available technologies according to the
following criteria:
1. Design and operating data associated with the treatment data
must reflect a well-designed, well-operated system for each
treatment data point. (The specific design and operating
parameters for each demonstrated technology for this waste code
are discussed in Section 3.2 of this document.)
2. Sufficient QA/QC data must be available to determine the true
values of the data from the treated waste. This screening
criterion involves adjustment of treated data to take into
account that the type value may be different from the measured
value. This discrepancy generally is caused by other
constituents in the waste that can mask results or otherwise
interfere with the analysis of the constituent of concern.
3. The measure of performance must be consistent with EPA's
approach to evaluating treatment by type of constituents (e.g.,
total concentration data for organics, and total concentration
and TCLP for metals in the leachate from the residual).
In the absence of data needed to perform the screening analysis, EPA
will make decisions on a case-by-case basis as to whether to include the
data. The factors included in this case-by-case analysis will be the
32
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actual treatment levels achieved, the availability of the treatment data
and their completeness (with respect to the above criteria), and EPA's
assessment of whether the untreated waste represents the waste code of
concern. EPA's application of these screening criteria for this waste
code is provided in Section 4 of this background document.
(2) Comparison of treatment data. In cases in which EPA has
treatment data from more than one technology following the screening
activity, EPA uses the statistical method known as analysis of variance
(ANOVA) to determine if one technology performs significantly better than
the others. This statistical method (summarized in Appendix A) provides
a measure of the differences between two data sets. If EPA finds that
one technology performs significantly better (i.e., the data sets are not
homogeneous), BOAT treatment standards are the level of performance
achieved by the best technology multiplied by the corresponding
variability factor for each regulated constituent.
If the differences in the data sets are not statistically
significant, the data sets are said to be homogeneous. Specifically, EPA
uses the analysis of variance to determine whether BOAT represents a
level of performance achieved by only one technology or represents a
level of performance achieved by more than one (or all) of the
technologies. If the Agency finds that the levels of performance for one
or more technologies are not statistically different, EPA averages the
performance values achieved by each technology and then multiplies this
value by the largest variability factor associated with any of the
33
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acceptable technologies. A detailed discussion of the treatment
selection method and an example of how EPA chooses BOAT from multiple
treatment systems is provided in Section A-l.
(3) Quality assurance/quality control. This section presents the
principal quality assurance/quality control (QA/QC) procedures employed
in screening and adjusting the data to be used in the calculation of
treatment standards. Additional QA/QC procedures used in collecting and
screening data for the BOAT program are presented in EPA's Generic
Quality Assurance Project Plan for Land Disposal Restrictions Program
("BOAT") (EPA/530-SW-87-011, March 1987).
To calculate the treatment standards for the Land Disposal
Restriction Rules, it is first necessary to determine the recovery value
for each constituent (the amount of constituent recovered after spiking,
which is the addition of a known amount of the constituent, minus the
initial concentration in the samples divided by the amount added) for a
spike of the treated residual. Once the recovery value is determined,
the following procedures are used to select the appropriate percent
recovery value to adjust the analytical data:
1. If duplicate spike recovery values are available for the
constituent of interest, the data are adjusted by the lowest
available percent recovery value (i.e., the value that will
yield the most conservative estimate of treatment achieved).
However, if a spike recovery value of less than 20 percent is
reported for a specific constituent, the data are not used to
set treatment standards because the Agency does not have
sufficient confidence in the reported value to set a national
standard.
34
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2. If data are not available for a specific constituent but are
available for an isomer, then the spike recovery data are
transferred from the isomer and the data are adjusted using the
percent recovery selected according to the procedure described
in 1 above.
3. If data are not available for a specific constituent but are
available for a similar class of constituents (e.g., volatile
organics, acid-extractable semivolatiles), then spike recovery
data available for this class of constituents are transferred.
All spike recovery values greater than or equal to 20 percent
for a spiked sample are averaged and the constituent
concentration is adjusted by the average recovery value. If
spike recovery data are available for more than one sample, the
average is calculated for each sample and the data are adjusted
by the lowest average value.
4. If matrix spike recovery data are not available for a set of
data to be used to calculate treatment standards, then matrix
spike recovery data are transferred from a waste that the Agency
believes is a similar matrix (e.g., if the data are for an ash
from incineration, then data from other incinerator ashes could
be used). While EPA recognizes that transfer of matrix spike
recovery data from a similar waste is not an exact analysis,
this is considered the best approach for adjusting the data to
account for the fact that most analyses do not result in
extraction of 100 percent of the constituent. In assessing the
recovery data to be transferred, the procedures outlined in 1,
2, and 3 above are followed.
The analytical procedures employed to generate the data used to
calculate the treatment standards are listed in Appendix B of this
document. In cases where alternatives or equivalent procedures and/or
equipment are allowed in EPA's SW-846, Third Edition (November 1986)
methods, the specific procedures and equipment used are also documented
in this appendix. In addition, any deviations from the SW-846, Third
Edition, methods used to analyze the specific waste matrices are
documented. It is important to note that the Agency will use the methods
and procedures delineated in Appendix B to enforce the treatment
35
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standards presented in Section 6 of this document. Accordingly,
facilities should use these procedures in assessing the performance of
their treatment systems.
1.2.7 BOAT Treatment Standards for "Derived-From" and "Mixed" Wastes
(1) Wastes from treatment trains generating multiple residues. In a
number of instances, the proposed BOAT consists of a series of
operations, each of which generates a waste residue. For example, the
proposed BOAT for a certain waste code is based on solvent extraction,
steam stripping, and activated carbon adsorption. Each of these
treatment steps generates a waste requiring treatmenta
solvent-containing stream from solvent extraction, a stripper overhead,
and spent activated carbon. Treatment of these wastes may generate
further residues; for instance, spent activated carbon (if not
regenerated) could be incinerated, generating an ash and possibly a
scrubber water waste. Ultimately, additional wastes are generated that
may require land disposal. With respect to these wastes, the Agency
wishes to emphasize the following points:
1. All of the residues from treating the original listed wastes are
likewise considered to be the listed waste by virtue of the
derived-from rule contained in 40 CFR Part 261.3(c)(2). (This
point is discussed more fully in (2) below.) Consequently, all
of the wastes generated in the course of treatment would be
prohibited from land disposal unless they satisfy the treatment
standard or meet one of the exceptions to the prohibition.
2. The Agency's proposed treatment standards generally contain a
concentration level for wastewaters and a concentration level
for nonwastewaters. The treatment standards apply to all of the
wastes generated in treating the original prohibited waste.
Thus, all solids generated from treating these wastes would have
36
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to meet the treatment standard for nonwastewaters. All
derived-from wastes meeting the Agency definition of wastewater
(less than 1 percent TOC and less than 1 percent total
filterable solids) would have to meet the treatment standard for
wastewaters. EPA wishes to make clear that this approach is not
meant to allow partial treatment in order to comply with the
applicable standard;
3. The Agency has not performed tests, in all cases, on every waste
that can result from every part of the treatment train.
However, the Agency's treatment standards are based on treatment
of the most concentrated form of the waste. Consequently, the
Agency believes that the less concentrated wastes generated in
the course of treatment will also be able to be treated to meet
this value.
(2) Mixtures and other derived-from residues. There is a further
question as to the applicability of the BOAT treatment standards to
residues generated not from treating the waste (as discussed above), but
from other types of management. Examples are contaminated soil or
leachate that is derived from managing the waste. In these cases, the
mixture is still deemed to be the listed waste, either because of the
derived-from rule (40 CFR Part 261.3(c)(2)(i)) or the mixture rule
(40 CFR Part 261.3(a)(2)(iii) and (iv)) or because the listed waste is
contained in the matrix (see, for example, 40 CFR Part 261.33(d)). The
prohibition for the particular listed waste consequently applies to this
type of waste.
The Agency believes that the majority of these types of residues can
meet the treatment standards for the underlying listed wastes (with the
possible exception of contaminated soil and debris, for which the Agency
is currently investigating whether it is appropriate to establish a
separate treatability subcategorization). For the most part, these
37
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residues will be less concentrated than the original listed waste. The
Agency's treatment standards also make a generous allowance for process
variability by assuming that all treatability values used to establish
the standard are lognormally distributed. The waste also might be
amenable to a relatively nonvariable form of treatment technology such as
incineration. Finally, and perhaps most important, the rules contain a
treatability variance that allows a petitioner to demonstrate that its
waste cannot be treated to the level specified in the rule (40 CFR Part
268.44(a)). This provision provides a safety valve that allows persons
with unusual waste matrices to demonstrate the appropriateness of a
different standard. The Agency, to date, has not received any petitions
under this provision (for example, for residues contaminated with a
prohibited solvent waste), indicating, in the Agency's view, that the
existing standards are generally achievable.
(3) Residues from managing listed wastes or that contain listed
wastes. The Agency has been asked if and when residues from managing
hazardous wastes, such as leachate and contaminated ground water, become
subject to the land disposal prohibitions. Although the Agency believes
this question to be settled by existing rules and interpretative
statements, to avoid any possible confusion the Agency will address the
question again.
Residues from managing First Third wastes, listed California List
wastes, and spent solvent and dioxin wastes are all considered to be
subject to the prohibitions for the underlying hazardous waste. Residues
38
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from managing California List wastes likewise are subject to the
California List prohibitions when the residues themselves exhibit a
characteristic of hazardous waste. This determination stems directly
from the derived-from rule in 40 CFR Part 261.3(c)(2) or, in some cases,
from the fact that the waste is mixed with or otherwise contains the
listed waste. The underlying principle stated in all of these provisions
is that listed wastes remain listed until delisted.
The Agency's historic practice in processing delisting petitions that
address mixing residuals has been to consider them to be the listed waste
and to require that delisting petitioners address all constituents for
which the derived-from waste (or other mixed waste) was listed. The
language in 40 CFR Part 260.22(b) states that mixtures or derived-from
residues can be delisted provided a delisting petitioner makes a
demonstration identical to that which a delisting petitioner would make
for the underlying waste. Consequently, these residues are treated as
the underlying listed waste for delisting purposes. The statute likewise
takes this position, indicating that soil and debris that are
contaminated with listed spent solvents or dioxin wastes are subject to
the prohibition for these wastes even though these wastes are not the
originally generated waste, but rather are a residual from management
(RCRA section 3004(e)(3)). It is EPA's view that all such residues are
covered by the existing prohibitions and treatment standards for the
listed hazardous waste that these residues contain and from which they
are derived.
39
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1.2.8 Transfer of Treatment Standards
EPA is proposing some treatment standards that are not based on
testing of the treatment technology of the specific waste subject to the
treatment standard. Instead, the Agency has determined that the
constituents present in the subject waste can be treated to the same
performance levels as those observed in other wastes for which EPA has
previously developed treatment data. EPA believes that transferring
treatment performance for use in establishing treatment standards for
untested wastes is technically valid in cases where the untested wastes
are generated from similar industries, have similar processing steps, or
have similar waste characteristics affecting performance and treatment
selection. Transfer of treatment standards to similar wastes or wastes
from similar processing steps requires little formal analysis. However,
in a case where only the industry is similar, EPA more closely examines
the waste characteristics prior to deciding whether the untested waste
constituents can be treated to levels associated with tested wastes.
EPA undertakes a two-step analysis when determining whether wastes
generated by different processes within a single industry can be treated
to the same level of performance. First, EPA reviews the available waste
characteristic data to identify those parameters that are expected to
affect treatment selection. EPA has identified some of the most
important constituents and other parameters needed to select the
treatment technology appropriate for a given waste. A detailed
discussion of each analysis, including how each parameter was selected
for each waste, can be found in Section 5 of this document.
40
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Second, when an individual analysis suggests that an untested waste
can be treated with the same technology as a waste for which treatment
performance data are already available, EPA analyzes a more detailed list
of constituents that represent some of the most important waste
characteristics that the Agency believes will affect the performance of
the technology. By examining and comparing these characteristics, the
Agency determines whether the untested wastes will achieve the same level
of treatment as the tested waste. Where the Agency determines that the
untested waste is easier to treat than the tested waste, the treatment
standards can be transferred. A detailed discussion of this transfer
process for each waste can be found in later sections of this document.
1.3 Variance from the BOAT Treatment Standard
The Agency recognizes that there may exist unique wastes that cannot
be treated to the level specified as the treatment standard. In such a
case, a generator or owner/operator may submit a petition to the
Administrator requesting a variance from the treatment standard. A
particular waste may be significantly different from the wastes
considered in establishing treatability groups because the waste contains
a more complex matrix that makes it more difficult to treat. For
example, complex mixtures may be formed when a restricted waste is mixed
with other waste streams by spills or other forms of inadvertent mixing.
As a result, the treatability of the restricted waste may be altered such
that it cannot meet the applicable treatment standard.
Variance petitions must demonstrate that the treatment standard
established for a given waste cannot be met. This demonstration can be
41
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made by showing that attempts to treat the waste by available
technologies were not successful or by performing appropriate analyses of
the waste, including waste characteristics affecting performance, which
demonstrate that the waste cannot be treated to the specified levels.
Variances will not be granted based solely on a showing that adequate
BOAT treatment capacity is unavailable. (Such demonstrations can be made
according to the provisions in Part 268.5 of RCRA for case-by-case
extensions of the effective date.) The Agency will consider granting
generic petitions provided that representative data are submitted to
support a variance for each facility covered by the petition.
Petitioners should submit at least one copy to:
The Administrator
U.S. Environmental Protection Agency
401 M Street, S.W.
Washington, DC 20460
An additional copy marked "Treatability Variance" should be submitted
to:
Chief, Waste Treatment Branch
Office of Solid Waste (WH-565)
U.S. Environmental Protection Agency
401 M Street, S.W.
Washington, DC 20460
Petitions containing confidential information should be sent with
only the inner envelope marked "Treatability Variance" and "Confidential
Business Information" and with the contents marked in accordance with the
requirements of 40 CFR Part 2 (41 FR 36902, September 1, 1976, amended by
43 FR 4000).
The petition should contain the following information:
42
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1. The petitioner's name and address.
2. A statement of the petitioner's interest in the proposed action.
3. The name, address, and EPA identification number of the facility
generating the waste, and the name and telephone number of the
plant contact.
4. The process(es) and feed materials generating the waste and an
assessment of whether such process(es) or feed materials may
produce a waste that is not covered by the demonstration.
5. A description of the waste sufficient for comparison with the
waste considered by the Agency in developing BOAT, and an
estimate of the average and maximum monthly and annual
quantities of waste covered by the demonstration. (Note: The
petitioner should consult the appropriate BOAT background
document for determining the characteristics of the wastes
considered in developing treatment standards.)
6. If the waste has been treated, a description of the system used
for treating the waste, including the process design and
operating conditions. The petition should include the reasons
the treatment standards are not achievable and/or why the
petitioner believes the standards are based on inappropriate
technology for treating the waste. (Note: The petitioner should
refer to the BOAT background document as guidance for
determining the design and operating parameters that the Agency
used in developing treatment standards.)
7. A description of the alternative treatment systems examined by
the petitioner (if any); a description of the treatment system
deemed appropriate by the petitioner for the waste in question;
and, as appropriate, the concentrations in the treatment
residual or extract of the treatment residual (i.e., using the
TCLP, where appropriate, for stabilized metals) that can be
achieved by applying such treatment to the waste.
8. A description of those parameters affecting treatment selection
and waste characteristics that affect performance, including
results of all analyses. (See Section 3.0 for a discussion of
waste characteristics affecting performance that the Agency has
identified for the technology representing BOAT.)
9. The dates of the sampling and testing.
10. A description of the methodologies and equipment used to obtain
representative samples.
43
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11. A description of the sample handling and preparation techniques,
including techniques used for extraction, containerization, and
preservation of the samples.
12. A description of analytical procedures used, including QA/QC
methods.
After receiving a petition for a variance, the Administrator may
request any additional information or waste samples that may be required
to evaluate and process the petition. Additionally, all petitioners must
certify that the information provided to the Agency is accurate under
40 CFR Part 268.4(b).
In determining whether a variance will be granted, the Agency will
first look at the design and operation of the treatment system being
used. If EPA determines that the technology and operation are consistent
with BOAT, the Agency will evaluate the waste to determine if the waste
matrix and/or physical parameters are such that the BOAT treatment
standards reflect treatment of this waste. Essentially, this latter
analysis will concern the parameters affecting treatment selection and
waste characteristics affecting performance parameters.
In cases where BOAT is based on more than one technology, the
petitioner will need to demonstrate that the treatment standard cannot be
met using any of the technologies, or that none of the technologies are
appropriate for treatment of the waste. After the Agency has made a
determination on the petition, the Agency's findings will be published in
the Federal Register, followed by a 30-day period for public comment.
44
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After review of the public comments, EPA will publish its final
determination in the Federal Register as an amendment to the treatment
standards in 40 CFR Part 268, Subpart D.
45
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2. INDUSTRIES AFFECTED AND WASTE CHARACTERIZATION
The previous section discussed the BDAT program and the methodology
used by the Agency to develop treatment standards. The purpose of this
section is to describe the industry affected by the land disposal
restrictions for F006, the process generating the waste, and the
available waste characterization data.
2.1 Industry Affected
The listed waste F006 is generated as the wastewater treatment
sludges from electroplating operations except for certain processes
including anodizing of aluminum; tin, zinc, aluminum, or zinc-aluminum
plating on carbon steel and associated cleaning/stripping; and chemical
etching and milling of aluminum. Electroplating is broadly defined by
the Agency to include electroplating, anodizing, chemical conversion
coating, electroless plating, immersion plating, chemical etching and
milling, and printed circuit board manufacture (51 FR 43350). Using the
1985 Biennial Report Data Base, EPA identified approximately 4,500
facilities as generators of F006 wastes. Figure 2-1 depicts the number
of F006 generators by State, while Table 2-1 identifies the number of
F006 generators by State and by Region. In the preamble for the Effluent
Limitation Guidelines for the Metal Finishing Industry (40 CFR Part 413),
the Agency identified 13,500 facilities in the electroplating/metal
finishing industry that use 46 electroplating and metal finishing unit
operations listed in 48 FR 32482. The 4,500 facilities generating F006
are a subset of the 13,500 facilities in the metal finishing industry.
46
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PUERTO RICO
VIRGIN ISLANDS
17
GEOGRAPHICAL DISTRIBUTION OF ELECTROPLATING
FACILITIES GENERATING F006 WASTE
FIGURE 2-1
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1670g/p 26
Table 2-1 Facilities Producing F006 Waste
by State and Region
EPA Region
1
II
III
IV
V
VI
State
Connecticut
Maine
Massachusetts
New Hampshire
Rhode Island
Vermont
New York
New Jersey
Puerto Rico
Virgin Islands
Delaware
Pennsylvania
Maryland
Virginia
West Virginia
Washington, D.C.
Alabama
Georgia
Florida
Kentucky
North Carolina
Mississippi
South Carolina
Tennessee
Illinois
Indiana
Michigan
Minnesota
Ohio
Wisconsin
Arkansas
Louisiana
New Mexico
Oklahoma
Texas
Number of facilities
252
18
264
29
69
10
314
160
27
0
5
223
39
47
7
1
54
40
114
40
92
16
62
72
259
131
237
59
276
88
35
22
10
39
169
48
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1670g/p 26
Table 2-1 (Continued)
EPA Region
State
Number of facilities
VII
Iowa
Kansas
Missouri
Nebraska
43
20
73
15
VIII
IX
Colorado
Montana
North Dakota
South Dakota
Utah
Wyoming
California
Arizona
Nevada
51
2
3
4
26
0
854
68
18
Oregon
Washington
Hawaii
Idaho
Alaska
34
38
4
9
0
4544
Source: USEPA 1988. F006 generators data extracted from 1985 Biennial
Report data base computer run dated March 12, 1988.
49
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Generators of F006 generally fall under Standard Industrial
Classification (SIC) code series 2000 and 3000 described as the
fabricated metal products except machinery and transportation equipment;
machinery except electrical; electrical and electronic machinery,
equipment and supplies; transportation equipment; measuring, analyzing,
and controlling instruments; and miscellaneous manufacturing industries.
EPA is currently compiling data and information on the amount of F006
generated and the quantities of F006 wastes land disposed. One source of
information estimates that 1.4 million tons of F006 waste is generated in
this country each year. The Agency estimates, on the basis of the
recently compiled EPA Treatment, Storage, Disposal and Recovery Survey,
that approximately 5 million tons of F006 waste is land disposed every
year.
2.2 Process Descriptions
Below are descriptions of each of the six operations that EPA has
defined as "electroplating." These operations include electroplating,
anodizing, chemical conversion coating (i.e., coloring, chromating,
proplating, and passivation), electroless plating, chemical etching and
milling, and printed circuit board manufacturing. Figure 2-2 presents a
general schematic of an electroplating wastewater system and shows where
F006 is generated.
2.2.1 Electroplating
Electroplating is the application of a thin surface coating of one
metal upon another by electrodeposition. This surface coating is applied
to provide corrosion protection, wear or erosion resistance,
50
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Cyanide
Wastewaters _
(Not F007, F008
or F009)
Hexavalent
Chromium
Wastewaters
Treatment
Chemicals
8 ^
Oxidizing
Agent Caustic
1 1
Cyanide
Rlnee Waters
Collection
Tank
Cyanide
Tank
Reducing
Agent Acid
1 i
Cr+e
Rinse Waters
Collection
Tank
Chromium
R aid ii f*t 1 a n
Tank
Acid/Alkali
Wastewaters
Collection
Tank
f
Precipitation
Reaction or
Neutralization
Tank
Polymer
I
Clarlfler
Filter
F006
(Sludge)
Filtrate to Sewer
or Surface Water
or Recycled to
Collection Tank
Figure 2-2 General Schematic of a Wastewater Treatment System
-------
or antifrictional characteristics, or for decorative purposes. The
electroplating of common metals includes the processes in which ferrous
or nonferrous base material is electroplated with the following metals or
metal alloys: copper, nickel, chromium, brass, bronze, zinc, tin, lead,
cadmium, iron, aluminum, or combinations thereof. The alloy brass
consists of copper and zinc; the alloy bronze consists of copper and
tin. Precious metals electroplating includes the processes in which a
ferrous or nonferrous base material is plated with gold, silver,
palladium, platinum, rhodium, indium, ruthenium, iridium, osmium, or
combinations thereof.
In electroplating, metal ions in acid, alkaline, or neutral solutions
are reduced on cathodic surfaces. The cathodic surfaces are the
workpieces being plated. The metal ions in solution are usually
replenished by the dissolution of metal from anodes or small pieces
contained in inert wire or metal baskets. Replenishment with metal salts
is also practiced, especially for chromium plating. In this case, an
inert material must be selected for the anodes. Hundreds of different
electroplating solutions have been adopted commercially, but only two or
three types are used widely for a particular metal or alloy. For
example, cyanide solutions are popular for copper, zinc, brass, cadmium,
silver, and gold. However, noncyanide alkaline solutions containing
pyrophosphate have come into use recently for zinc and copper. Acid
sulfate solutions are used for plating zinc, copper, tin, and nickel,
especially, relatively simple shapes. Cadmium and zinc are
52
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sometimes electroplated from neutral or slightly acidic chloride
solutions.
Electroplating baths contain metals, metal salts, acids, alkalies,
and various bath control coupounds. All of these material contribute to
the wastewater streams either through part dragout, batch dump, or floor
spill. The sludge from spent plating baths also contains metals.
Table 2-2 outlines some typical electroplating bath chemical compositions.
2.2.2 Anodizing
Anodizing is an electrolytic oxidation process that converts the
surface of the metal to an insoluble oxide. These oxide coatings provide
corrosion protection, decorative surfaces, a base for painting and other
coating processes, and special electrical and mechanical properties.
Aluminum is the most frequently anodized material, while some magnesium,
stainless steel (electropolish), and limited amounts of zinc and
titanium are also treated.
Although most of anodizing is carried out by the immersion of racked
parts in tanks, continuous anodizing is done on large coils of aluminum
is performed in a manner similar to continuous electroplating. For
aluminum parts, the formation of the oxide occurs when the parts are made
anodic in dilute sulfuric acid or dilute chromic acid solutions. The
oxide layer begins formation at the extreme outer surface, and as the
reaction proceeds, the oxide grows into the metal. The oxide formed
last, known as the boundary layer, is located at the interface between
the base metal and oxide. The boundary is extremely thin and nonporous.
The sulfuric acid process is typically used for all parts fabricated from
53
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1670g/p 20
Table 2-2 Typical Electroplating Baths and Their Chemical Composition
Plating compound
Constituents
Concentration (g/1)
Cadmium Cyanide
Cadmium oxide
Cadmium
Sodium cyanide
Sodium hydroxide
22.5
19.5
77.9
14.2
Cadmium Fluoroborate
Cadmium fluoroborate
Cadmium (as metal)
Ammonium fluoroborate
Boric acid
Licorice
251.2
94.4
59.9
27.0
1.1
Chromium Electroplate
Chromic acid
Sulfate
Fluoride
172.3
1.3
0.7
Copper Cyanide
Copper cyanide
Free sodium cyanide
Sodium carbonate
Roche lie salt
26.2
5.6
37.4
44.9
Electro less Copper
Gold Cyanide
Acid Nickel
Copper nitrate
Sodium bicarbonate
Rochelie salt
Sodium hydroxide
Formaldehyde (37%)
Gold (as potassium
gold cyanide)
Potassium cyanide
Potassium carbonate
Oepotassium phosphate
Nickel sulfate
Nickel chloride
Boric acid
15
10
30
20
100 ml/1
8
30
30
30
330
45
37
SiIver Cyanide
Silver cyanide
Potassium cyanide
Potassium carbonate (min.
Metallic silver
Free cyanide
35.9
59.9
15.0
23.8
41.2
54
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1670g/p 16
Table 2-2 (continued)
Plating compound
Zinc Sulfate
Constituents
i Zinc sulfate
Sodium sulfate
1 Magnesium sulfate
Concentration
374.5
71.5
59.9
(g/D
Source: USEPA 1980. RCRA. Listing Background Document Waste Code F006.
55
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aluminum alloys except for parts subject to stress or containing recesses
in which the sulfuric acid solution may be retained and attack the
aluminum. Chromic acid anodic coatings are more protective than sulfuric
acid coatings and have a relatively thick boundary layer. For these
reasons, a chromic acid bath is used if a complete rinsing of the part
cannot be achieved.
2.2.3 Chemical Conversion Coating
This manufacturing operation includes chromating, phosphating, metal
coloring, and passivating. These coatings are applied to previously
deposited metal or base material for increased corrosion protection,
lubricity, preparation of the surface for additional coatings, or
formulation of a special surface appearance. In chromating, a partition
of the base metal is converted to one of the components of the protective
film formed by the coating solution. This occurs by reaction with
aqueous solutions containing hexavalent chromium and active organic or
inorganic compounds. Chromate coatings are most frequently applied to
zinc, cadmium, magnesium, copper, brass, bronze, and silver. Most of the
coatings are applied by chemical immersion, although a spray or brush
treatment can be used. Changes in the solutions can impart a wide range
of colors to the coatings from colorless to iridescent yellow, brass,
brown, and olive drab. Additional coloring of the coatings can be
achieved by dipping the parts in organic dye baths to produce red, green,
blue, and other colors.
Phosphate coatings are used to provide a good base for paints and
other organic coatings, to condition the surfaces for cold forming
56
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operations by providing a base for drawing compounds and lubricants, and
to impart corrosion resistance to the metal surface by the coating itself
or by providing a suitable base for rust-preventive oils or waxes.
Phosphate conversion coatings are formed by the immersion of iron, steel,
or zinc-plated steel in a dilute solution of phosphoric acid plus other
reagents. The method of applying the phosphate coating is dependent upon
the size and shape of the part to be coated. Small parts are coated in
barrels immersed in the phosphating solution. Large parts, such as steel
sheet and strip, are spray coated or continuously passed through the
phosphating solution. Supplemental oil or wax coatings are usually
applied after phosphating unless the part is to be painted.
Metal coloring by chemical conversion methods produces a large group
of decorative finishes. This operation covers only chemical methods of
coloring in which the metal surface is converted into an oxide or similar
metallic compound. The most common colored finishes are used on copper,
steel, zinc, and cadmium.
Application of the color to the cleaned base metal involves only a
brief immersion in a dilute aqueous solution. The colored films produced
on the metal surface are extremely thin and delicate. Consequently, they
lack resistance to handling and to the atmosphere. A clear lacquer is
often used to protect the colored metal surface. A large quantity of
copper and brass is colored to yield a wide variety of shades and
colors. Shades of black, brown, gray, green, and patina can be obtained
on copper and brass by use of appropriate coloring solutions. The most
57
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widely used colors for ferrous metals are based on oxides that yield
black, brown, or blue colors. A number of colors can be developed on
zinc depending on the length of immersion in the coloring solution.
Yellow, bronze, dark green, black, and brown colors can be produced on
cadmium. Silver is also colored commercially and is given a gray color
by immersion in a polysulfide solution such as ammonium polysulfide. Tin
can be darkened to produce an antique finish of pewter by immersion in a
solution of nitric acid and copper sulfate.
Passivation refers to the forming of a protective film on metals,
particularly stainless steel and copper, by immersion in an acid
solution. Stainless steel is passivated to dissolve any imbedded iron
particles and to form a thin oxide film on the surface of the metal.
Typical solutions for passivating stainless steel include nitric acid and
nitric acid with sodium dichromate. Copper is passivated with a solution
of ammonium sulfate and copper sulfate forming a blue-green patina on the
surface of the metal.
2.2.4 Electroless Plating
Electroless Plating is a chemical reduction process that depends upon
the catalytic reduction of a metallic ion in an aqueous solution
containing a reducing agent and the subsequent deposition of metal
without the use of external electrical energy. It has found widespread
use in industry because it has several unique advantages over
conventional electroplating. Electroless plating provides a uniform
plating thickness on all areas of the part regardless of the
configuration or geometry of the part. An electroless plate on a
58
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properly prepared surface is dense and virtually nonporous. Copper and
nickel electroless plating are the most common. The basic ingredients in
an electroless plating solution are:
1. A source of metal, usually a salt;
2. A reducer to reduce the metal to its base state;
3. A complexing agent to hold the metal in solution (so the metal
will not plate out indiscriminately); and
4. Various buffers and other chemicals designed to maintain bath
stability and increase bath life.
When electroless plating is done on a plastic basis material,
catalyst application and acceleration steps are necessary as surface
preparation operations. These steps are considered part of the
electroless plating unit operation.
Immersion plating is a chemical plating process in which a thin metal
deposit is obtained by chemical displacement on the base metal. Because
of the similarity of the wastes produced and the materials involved,
immersion plating is considered part of the electroless plating unit
operation. Unlike electroless plating, however, it is not an
autocatalytic process.
In immersion plating, a metal will displace from solution any other
metal that is below it in the electromotive series of elements. The
lower (more noble) metal will be deposited from solution while the more
active metal (higher in the series) will be dissolved. A common example
of immersion plating is the deposition of copper on steel from an acid
copper solution.
59
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2.2.5 Chemical Etching and Milling
These processes are used to produce specific design configurations
and tolerances or surface appearances on parts (or metal-clad plastic in
the case of printed circuit boards) by controlled dissolution with
chemical reagents or etchants. Included in this classification are the
processes of chemical milling, chemical etching, and bright dipping.
Chemical etching is the same process as chemical milling, but the rates
and depths of metal removal are usually much greater in chemical
milling. Typical solutions for chemical milling and etching include
ferric chloride, nitric acid, ammonium persulfate, chromic acid, cupric
chloride, hydrochloric acid, and combinations of these reagents. Bright
dipping is a specialized form of etching that is used to remove oxide and
tarnish from ferrous and nonferrous materials and is frequently performed
just prior to plating. Bright dipping can produce a range of surface
appearances from bright clean to brilliant depending on the surface
smoothness desired for the finished part. Bright dipping solutions
usually involve mixtures of two or more of these acids: sulfuric,
chromic, phosphoric, nitric, and hydrochloric. Also included in this
unit operation is the stripping of metallic coatings.
2.2.6 Printing Circuit Board Manufacture
Wastewater is produced in the manufacturing of printed circuit boards
from the following processes:
1. Surface preparation - The rinses following scrubbing, alkaline
cleaning, acid cleaning, etchback, catalyst application and
activation.
2. Electroless plating - Rinses following the electroless plating
step.
60
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3. Pattern plating - Rinses following acid cleaning, alkaline
cleaning, copper plating, and solder plating.
4. Etching - Rinses following etching and solder brightening.
5. Tab plating - Rinses following solder stripping; scrubbing; acid
cleaning; and nickel, gold, or other plating operations.
6. Immersion plating - Rinses following acid cleaning and immersion
tin plating.
Additionally, water may be used for subsidiary purposes such as
rinsing away spills, air scrubbing, equipment washing, and dumping spent
process solutions.
2.3 Waste Characterization
All waste characterization data available to the Agency for the F006
waste are summarized below. The major constituents in the waste and
their approximate concentrations are presented in Table 2-3. Table 2-4
presents the concentration of each BOAT list metal constituent and
cyanide in the waste. The concentration of individual metals is
dependent on the type of electroplating solutions used in the
electroplating process.
The waste characterization data presented in this background document
are solely for the F006 sludge generated following the treatment of
electroplating wastewaters. The Agency wishes to emphasize that sludges
generated from treatment of spent cyanide plating baths are also
classified as F007, F008, or F009 under EPA's "derived from" rule (40 CFR
261.3(c)(2)(i)). An example is a spent nickel sludge generated from
nickel cyanide plating solution (an F007 wastewater). This bath solution
is sent through cyanide destruction and metal hydroxide precipitation for
nickel removal. The precipitated residual is F007.
61
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1670g/p 26
Table 2-3 Major Constituents in F006 Waste
Constituent Concentrations (%)
Solids 2-73
(Consisting of metal precipitation
(usually hydroxides) and unreacted
treatment chemicals (generally lime))
Water 24-98
Cyanide 0-.05
Total organic carbon 0.04-3.0
100
62
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1670g/p J6
Table 2-4 Constituent Composition for Untreated F006 Waste
CO
Concentration (own)
Constituent Source 1
Metals
154. Antimony NA
155. Arsenic
156. Barium 0.74 - 85.5
157. Beryllium NA
158. Cadmium 1.3 - 720
159. Total chromium 2 - 49,000
160. Copper 1.4 - 27,400
161. Lead 1.69 - 24,500
162. Mercury
163. Nickel 234 - 23.700
164. Selenium
165. Silver 0.51 - 38.9
166. Thallium NA
167. Vanadium
168. Zinc 8.86 - 90.200
169. Cyanide total <0.1 - 506
169. Cyanide amenable <0.10 - 0.22
221. Hexavalent chromium NA
Orqanics (ppb)
Acetone
Aero le in
Acrylonitrile
Benzene
Bromod i ch loromet hane
Bromoform
Source 2
NA
NA
NA
NA
1,280 - 4,070
147 - 8,610
345 - 28,100
NA
NA
1,330 - 26,000
NA
NA
NA
-
611 - 41,200
84.1 - 226
<1 - 153
NA
-
-
-
-
-
-
Source 3
<10
2 - 5
20 - 45
<2
10 - 20
3,200 - 75.000
90 - 775
85 - 134
<1
7,300 -49.000
<10
<2
<10
-
68 - 3,700
<2
<2
0.14-1.0
<120 - <130
NA
NA
NA
<4.9 - <5.2
<4.9 - <5.2
Source 4
22.4
<0.4
28.8
<0.1
0.37-1.75
1,650-2,625
1.87-135
184-305
<0.2
11.8-17
<0.03
<0.6-<1.0
<20
1.26
2.510-3.687
-
-
NA
-
-
-
-
-
-
Source 5 Source 6
NA
<6.24
9-57
<97.6
<11-1.320 ND-22.000
35-730 200-137,000
<6-760
<6-408
<0.32
-
<19-<23
NA
NA
NA
<29-220
0.1-5.8 (0.1 free CN) -
-
0.25-25.4 NA
-
-
-
-
-
-
Source 7
-
-
-
-
0.003-1,180
< 0.002 -290. 000
-
<0. 001-13. 900
-
0.06-170,000
-
-
-
-
-
<0. 025-1. 970
0.003-162
<0. 001-910
-
-
-
-
-
-
Bromome thane
-------
1670g/p 17
Table 2-4 (continued)
Constituent
Source 1
Source 2
Concentration loom)
Source 3
Source 4
Source 5
Source 6
Source 7
Organic (continued)
2-Butanone
Carbon disulfide
Carbon tetrachloride
Chlorobenzene
Chloroethane
2-Chloroethyl vinyl ether
Chloroform
Chloromethane
Cis-l,3-dichloropropene
Dibromochloromethane
1,1-Dichloroethane
1,2-Oichloroethane
1,1-Dichloroethylene
1,2-Dtchloropropane
Ethylbenzene
2-Hexanone
Methylene chloride
4-Methyl-2-pentanone
Styrene
1,1,2,2-Tetrachloroethane
Tetrachlorethylene
Toluene
Trans-l,2-dichloroethylene
Trans-1,3-d i chloropropene
Trichloroethylene
Vinyl acetate
Vinyl chloride
Xylenes (total)
<25 - <26
<4.9 - <5.2
<4.9 - <5.2
<4.9 - <5.2
<4.9 - <5.2
<4.9 - <5.2
<4.9 - <5.2
<4.9 - <5.2
<4.9 - <5.2
<4.9 - <5.2
<4.9 - <5.2
<4.9 - <5.2
<4.9 - <5.2
<25 - <26
<25 - <26
<4.9 - <5.2
<4.9 - <5.2
<4.9 - <5.2
<4.9 - <5.2
<4.9 - <5.2
<4.9 - <5.2
NA
<4.9 - <5.2
-------
1670g/p 28
Table 2-4 (continued)
Concentration (DOT)
Constituent Source 1 Source 2 Source 3 Source 4 Source 5 Source 6 Source 7
Other Parameters
Fluoride - 268 - -
Oil and grease (rag/g) 0.03 - 37.7 ... . .
Moisture X 29.1-91.2 - 47.4-48.94 - - - -
SP gravity (g/ml) 1.38 - 1.493 - - - -
Acidity as CaCo3 (mg/1) 1.412 - -
Alkalinity as CaC03 (mg/1) - - - -
Sulfide - 21 -
Total organic carbon - - <5,800 - - -
NA - Not analyzed
Source 1 - Table 1 from Chemical Waste Management Report Technical Note 87-117.
September 22. 1987. The complete data set for this facility can be found in Appendix B.
Source 2 - MR1 draft memo to Ed Abrams, EPA-OSW, dated November 5, 1987.
Source 3 - Onsite Engineering Analysis Report for Envirite Corp., December 19, 1986, Table 6-13.
Source 4 - Memo to Ron Turner from R.O. Grotelueschem, John Deere Company, dated January 15. 1988.
Source 5 - F006 Waste description from Environ Report, 1984.
Source 6 - Listing Document Table 2 data provided on a dry-weight basis.
Source 7 - Data extracted for Table 3 of Draft Report. Review of Delisting Petitions for California List wastes subject to Land Disposal Restrictions,
Versar Inc., March 1986.
-------
3. APPLICABLE TREATMENT TECHNOLOGIES
In the previous section, a discussion of the industry and process
generating F006 waste and a major constituent analysis of this waste were
presented. This section describes the applicable and demonstrated
treatment technologies and performance data for treatment of F006 waste.
The technologies that are considered applicable to the treatment of F006
waste are those that treat BOAT list metals by reducing their
concentration and/or their Teachability in the waste. Included in this
section are discussions of those applicable treatment technologies that
have been demonstrated (i.e., are used on a commercial basis for
treatment of F006 waste). As shown in the previous section, F006 waste
is principally composed of water; precipitated metals including BOAT list
metals; and other solids; cyanides; and small amounts of volatile and
semi volatile organics. The individual organic constituents present in
F006 waste are measured at parts per billion levels. These
concentrations are not believed to be treatable.
3.1 Applicable Treatment Technologies
EPA has identified three technologies as potentially applicable for
treatment of F006 -- stabilization, vitrification, and metals recovery.
The first two technologies are designed to reduce the Teachability of the
metals; the third reduces both the total concentration and the
Teachability of the metals. Each of these applicable technologies is
described below.
66
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Stabilization chemically reduces the mobility of hazardous metal
constituents in a waste. Stabilizing agents, binders, and chemicals are
added to a waste to minimize the quantities of metals that leach when the
waste is in contact with water. Commonly used stabilization agents
I
include portland cement, lime/pozzolan-based material, and cement kiln
dust. Stabilization is described in Section 3.3.
Vitrification has also been identified by the Agency as an applicable
technology. A vitrification process is used to immobilize hazardous
constituents in the F006 waste to produce a vitrous or glass-like mass.
The Agency has no specific information related to the technology and/or
treatment performance and is soliciting information specific to the
vitrification of F006 waste from those facilities using this technology.
EPA has also identified high temperature metal recovery technologies
as applicable. All high temperature metal recovery technologies act to
reduce the concentration of metal in the waste through volatilization and
recovery.
3.2 Other Related F006 Treatment Technologies
EPA is aware of two other technologies that are not used for
treatment of F006 waste directly, but rather are used in the generation
of F006. Both of these technologies -- addition of lime to the
precipitated phosphate solids and metals recovery by crystallization --
generate an F006 waste that most likely would not require further
treatment prior to disposal. These two technologies are discussed below.
67
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The first technology, generically known as a phosphate precipitation
or a heavy metals precipitation method, is used during the generation of
wastewater treatment sludge (F006) to produce a stabilized F006 directly
from an aqueous concentrated solution containing heavy metals. The
processing steps of this patented, but commercially available, technology
begins with precipitation of heavy metals by adding phosphoric acid or an
acid phosphate salt to the aqueous solution. This initial precipitation
is followed by pH adjustment to pH 5, coagulation, and a final polishing
step, usually a second precipitation using lime. Sludge dewatering is
practiced on the mixed phosphate/lime sludges. The available data
indicate that some of the F006 wastes generated using this technology may
meet the treatment standards identified in Section 6.
A second technology, similar to a metals recovery technology that has
been demonstrated in Europe, is briefly discussed here. This process
crystallizes heavy metal carbonates on an inert material such as sand.
Using this treatment method, heavy metals in electroplating wastewaters
can be crystallized continuously. No sludge is produced; instead, the
settled treatment residue is in the form of granular metal carbonate
crystals (i.e., pellets) that can be reused in the electroplating
operation following the removal of metal carbonates by dissolving the
pellets in acid. Figure 3-1 is a schematic of the treatment. The
fluidized bed of sand is suspended in the reactor. A carbonate solution
and metal-containing wastewaters are fed at the bottom of the reactor.
Metal carbonates are formed on the seed material (i.e., sand granules).
68
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OUT
OF OPERATION
IN OPERATION
EFFLUENT
TO
FILTRATION
FLUIDIZED BED
GRAINS
INJECTION
NOZZLES
PERIODIC FEED
OF «
SEEDING GRAINS
_ METAL
"*SOLUTION
CARBONATE
SOLUTION
PERIODIC RELEASE
OF PELLETS
1
ACID
METALS RECOVERY
SAND
J
METAL CONCENTRATE
FIGURE 3-1 METALS RECOVERY BY CRYSTALLIZATION
69
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Once the carbonate granules grow to an acceptable level the flow is
switched to another reactor. The metal carbonate granules are removed
and new sand is added to the newly regenerated reactor for use when the
current reactor is shut down for regeneration. Pure metal carbonates are
removed by dissolving the pellets in acid. Recovered sand is recycled
into the system. Some metal carbonates remain in the reactor effluent
and are filtered. The viability of this technology depends on the extent
to which any standards for the wastewater can be achieved. EPA does not
have any data on the resulting wastewater or data confirming the actual
performance of this technology.
3.3 Demonstrated Treatment Technologies
EPA has information showing two of the applicable technologies to be
demonstrated. Stabilization is used by at least ten facilities to treat
F006 wastes. EPA knows of two facilities that use metals recovery for
F006 wastes. EPA knows of one facility that treats F006 waste by
vitrification and the Agency is in the process of obtaining information.
Below is a detailed discussion of stabilization, and high temperature
metal recovery.
3.3.1 Stabilization of Metals
Stabilization refers to a broad class of treatment processes that
chemically reduce the mobility of hazardous constituents in a waste.
Solidification and fixation are other terms that are sometimes used
synonymously for stabilization or to describe specific variations within
the broader class of stabilization. Related technologies are
.70
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encapsulation and thermoplastic binding; however, EPA considers these
technologies to be distinct from stabilization in that the operational
principles are significantly different.
(1) Applicability and use of stabilization. Stabilization is used
when a waste contains metals that will leach from the waste when it is
contacted by water. In general, this technology is applicable to wastes
containing BOAT list metals and having a high filterable solids content,
low TOC content, and low oil and grease content. This technology is
commonly used to treat residuals generated from treatment of
electroplating wastewaters. For some wastes, an alternative to
stabilization is metal recovery.
(2) Underlying principles of operation. The basic principle
underlying this technology is that stabilizing agents and other chemicals
are added to a waste to minimize the amount of metal that leaches. The
reduced Teachability is accomplished by the formation of a lattice
structure and/or chemical bonds that bind the metals to the solid matrix
and, thereby, limit the amount of metal constituents that can be leached
when water or a mild acid solution comes into contact with the waste
material.
There are two principal stabilization processes used -- these are
cement-based and lime-based. A brief discussion of each is provided
below. In both cement-based or lime/pozzolan-based techniques, the
stabilizing process can be modified through the use of additives, such as
silicates, that control curing rates or enhance the properties of the
solid material.
71
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(a) Portland cement-based process. Portland cement is a mixture of
powdered oxides of calcium, silica, aluminum, and iron, produced by kiln
burning of materials rich in calcium and silica at high temperatures
(i.e., 1400'C/2550'F to 1500'C/2730°F). When the
anhydrous cement powder is mixed with water, hydration occurs and the
cement begins to set. The chemistry involved is complex because many
different reactions occur depending on the composition of the cement
mixture.
As the cement begins to set, a colloidal gel of indefinite
composition and structure is formed. Over a period of time, the gel
swells and forms a matrix composed of interlacing, thin, densely packed
silicate fibrils. Constituents present in the waste slurry (e.g.,
hydroxides and carbonates of various heavy metals), are incorporated into
the interstices of the cement matrix. The high pH of the cement mixture
tends to keep metals in the form of insoluble hydroxide and carbonate
salts. It has been hypothesized that metal ions may also be incorporated
into the crystal structure of the cement matrix, but this hypothesis has
not been verified.
(b) Lime/pozzolan-based process. Pozzolan, which contains finely
divided, noncrystalline silica (e.g., fly ash or components of cement
kiln dust), is a material that is not cementitious in itself but becomes
so upon the addition of lime. Metals in the waste are converted to
silicates or hydroxides, which inhibit leaching. Additives, again, can
be used to reduce permeability and thereby further decrease leaching
potential.
72
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(c) Cement kiln dust process. A standard cement kiln dust (CKD)
method is used for liquid wastes that do not pass the paint filter test
(PFT) as received. Table 3-1 gives cement kiln dust composition data for
the type of dust used for the stabilization of F006 waste. When cement
kiln dust is used with liquid wastes, the mix ratio of l.is common; while
for solid wastes, the mix ratio is 0.2. If the water content is high,
then the higher mix ratio of 1.5 appears to be adequate. Typically, the
mixture is cured at 38DC/100°F to stimulate the temperature rise
for 24 hours. No additional additives or fixative agents are necessary;
at times, water may be added to the mixture to aid in mixing the waste
and stabilizing agent (in this case, cement kiln dust) and to maximize
utilization of the reagent.
(3) Description of stabilization processes. In most stabilization
processes, the waste, stabilizing agent, and other additives, if used,
are mixed and then pumped to a curing vessel or area and allowed to
cure. The actual operation (equipment requirements and process
sequencing) will depend on several factors such as the nature of the
waste, the quantity of the waste, the location of the waste in relation
to the disposal site, the particular stabilization formulation to be
used, and the curing rate. After curing, the solid formed is recovered
from the processing equipment and shipped for final disposal.
73
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1670g/p 16
Table 3-1 Cement Kiln Oust Composition Data
Concentration (mg/1)
Constituent Total composition TCLP Other characteristics
BOAT Metals
Arsenic 38 <0.01
Barium 92.7 2.74
Cadmium 3.14 <0.01
Chromium (total) 31.9 0.05
Copper 44.8 0.16
Lead 156 0.29
Mercury <0.033 <0.001
Nickel 12.6 0.02
Selenium 8.67 0.03
Silver 4.13 0.02
Zinc 65.6 0.04
Other Metals
Aluminum 31,000 NA
Iron (total) 15.200 NA
Magnesium 3.790 NA
Other Non-BDAT Constituents
Sodium 2300 NA
Potassium 33,100 NA
Calcium 41,900 NA
Total sulfide (ppm) <8
Ash content (%) 99.8
Total residue (@ 105'c)% 100
Alkalinity (as CaO %) 56.16
pH (10% solution) 12.55
NA = Not available
Source: Special waste analysis report dated June 15, 1987.
Provided by Chemical Waste Management (Technical Center).
74
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In instances where waste contained in a lagoon is to be treated, the
material should be first transferred to mixing vessels where stabilizing
agents are added. The mixed material is then fed to a curing pad or
vessel. After curing, the solid formed is removed for disposal.
Equipment commonly used also includes facilities to store waste and
chemical additives. Pumps can be used to transfer liquid or light sludge
wastes to the mixing pits and pumpable uncured wastes to the curing
site. Stabilized wastes are then removed to a final disposal site.
Commercial concrete mixing and handling equipment generally can be
used with wastes. Weighing conveyors, metering cement hoppers, and
mixers similar to concrete batching plants have been adapted in some
operations. Where extremely dangerous materials are being treated,
remote-control and in-drum mixing equipment, such as that used with
nuclear waste, can be employed.
(4) Waste characteristics affecting performance. In determining
whether stabilization is likely to achieve the same level of performance
on an untested waste as on a previously tested waste, the Agency will
focus on the characteristics that inhibit the formation of either the
chemical bonds or the lattice structure. The four characteristics EPA
has identified as affecting treatment performance are the presence of (1)
fine particulates, (2) oil and grease, (3) organic compounds, and (4)
certain inorganic compounds.
(a) Fine Particulates. For both cement-based and
lime/pozzolan-based processes, the literature states that very fine solid
75
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materials (i.e., those that pass through a No. 200 mesh sieve, 74 urn
particle size) can weaken the bonding between waste particles and cement
by coating the particles. This coating can inhibit chemical bond
formation and decrease the resistance of the material to leaching.
(b) Oil and Grease. The presence of oil and grease in both
cement-based and lime/pozzolan-
based systems results in the coating of waste particles and the weakening
of the bonding between the particle and the stabilizing agent. This
coating can inhibit chemical bond formation, thereby, decreasing the
resistance of the material to leaching.
(c) Organic Compounds. The presence of organic compounds in the
waste interferes with the chemical reactions and bond formation, which
inhibits curing of the stabilized material. This results in a stabilized
waste having decreased resistance to leaching.
(d) Sulfate and Chlorides. The presence of certain inorganic
compounds will interfere with the chemical reactions, weakening bond
strength and prolonging setting and curing time. Sulfate and chloride
compounds may reduce the dimensional stability of the cured matrix,
thereby increasing Teachability potential.
Accordingly, EPA will examine these constituents when making
decisions regarding transfer of treatment standards based on
stabilization.
76
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(5) Design and operating parameters. In designing a stabilization
system, the principal parameters that should be optimized so that the
amount of Teachable metal constituents is minimized are (1) selection of
stabilizing agents and other^additives, (2) ratio of waste to stabilizing
agents and other additives, (3) degree of mixing, and (4) curing
conditions.
(a) Selection of stabilizing agents and other additives. The
stabilizing agent and additives used will determine the chemistry and
structure of the stabilized material and, therefore, will affect the
Teachability of the solid material. Stabilizing agents and additives
must be carefully selected based on the chemical and physical
characteristics of the waste to be stabilized. For example, the amount
of sulfates in a waste must be considered when a choice is being made
between a lime/pozzolan-based system and a Portland cement-based system.
To select the type of stabilizing agents and additives, the waste
should be tested in the laboratory with a variety of materials to
determine the best combination.
(b) Amount of stabilizing agents and other additives. The
amount of stabilizing agents and other additives is a critical parameter
in that sufficient stabilizing materials are necessary in the mixture to
bind the waste constituents of concern properly, thereby making them less
susceptible to leaching. The appropriate weight ratios of waste to
stabilizing agent and other additives are established empirically by
setting up a series of laboratory tests that allow separate leachate
77
-------
testing of different mix ratios. The ratio of water to stabilizing agent
(including water in waste) will also impact the strength and leaching
characteristics of the stabilized material. Too much water will cause
low strength; too little will make mixing difficult and, more
importantly, may not allow the chemical reactions that bind the hazardous
constituents to be fully completed.
(c) Mixing. The conditions of mixing include the type and
duration of mixing. Mixing is necessary to ensure homogeneous
distribution of the waste and the stabilizing agents. Both undermixing
and overmixing are undesirable. The first condition results in a
nonhomogeneous mixture; therefore, areas will exist within the waste
where waste particles are neither chemically bonded to the stabilizing
agent nor physically held within the lattice structure. Overmixing, on
the other hand, may inhibit gel formation and ion adsorption in some
stabilization systems. As with the relative amounts of waste,
stabilizing agent, and additives within the system, optimal mixing
conditions generally are determined through laboratory tests. During
treatment it is important to monitor the degree (i.e., type and duration)
of mixing to ensure that it reflects design conditions.
(d) Curing conditions. The curing conditions include the
duration of curing and the ambient curing conditions (temperature and
humidity). The duration of curing is a critical parameter to ensure that
the waste particles have had sufficient time in which to form stable
chemical bonds and/or lattice structures. The time necessary for
78
-------
complete stabilization depends upon the waste type and the stabilization
used. The performance of the stabilized waste (i.e., the levels of
constituents in the leachate) will be highly dependent upon whether
complete stabilization has occurred. Higher temperatures and lower
humidity increase the rate of curing by increasing the rate of
evaporation of water from the solidification mixtures. However, if
temperatures are too high, the evaporation rate can be excessive,
resulting in too little water being available for completion of the
stabilization reaction. The duration of the curing process, which should
also be determined during the design stage, typically will be between 7
and 28 days.
3.3.2 High Temperature Metals Recovery
High temperature metals recovery (HTMR) provides for recovery of
metals from wastes primarily by volatilization and collection. The
process yields a metal product or products for reuse and reduces the
concentration of metals in the residual. This process also significantly
reduces the amount of treated waste that needs to be land disposed.
There are a number of different types of high temperature metal
recovery systems, which these systems generally differ from one another
relative to the source of energy and the method of recovery. Such HTMR
systems include the rotary kiln process, plasma arc reactor, rotary
hearth/electric furnace system, molten slag reactor, and flame reactor.
This technology is different from retorting in that HTMR is conducted in
a carbon-reducing atmosphere while the retorting process simply vaporizes
79
-------
the untreated metal. Retorting is discussed in a separate technology
section.
(1) Applicability and use of high temperature metals recovery. This
process is applicable to wastes containing BOAT list metals, low water
content (or a water content that can either be blended to the required
level or lowered by dewatering), and low concentration of organics. This
technology is applicable to a wide range of metal salts including
cadmium, chromium, lead, mercury, nickel, and zinc.
This process is generally not used for mercury-containing wastes even
though mercury will volatilize readily at the process temperatures
present in high temperature units. The rotary kiln recovery process is
one example of the technology, and it has been applied to zinc-bearing
wastes as an upgrading step that yields a zinc oxide product for further
refinement and subsequent reuse. Although this technology was originally
developed in the 1920s for upgrading zinc from ores, it has recently been
applied to electric furnace dust from the steel-making industry.
(2) Underlying principles of operation. The basic principle of
operation for this technology is that metals are separated from a waste
through volatilization in a reducing atmosphere where carbon is the
reducing compound. An example chemical reaction would be:
2ZnO + C - 2Zn + CO
In some cases, the waste contains not only BOAT list metal
constituents that can be volatilized but also nonvolatile BOAT list
metals. In such cases, the HTMR process can yield two recoverable
80
-------
product streams. Whether such recovery can be accomplished, however,
depends on the type and concentration of metals in the original
wastestream. Below is a discussion of the recovery techniques for the
volatile stream, as well as for the waste material that is not
i
volatilized.
(a) Recovery of volatilized metals. The volatilized metals can
be recovered in the metallic form or as an oxide. Recovery is
accomplished in the case of the metallic form by condensation alone and
in the case of the oxide by reoxidation, condensation, and subsequent
collection of the metal oxide particulates in a baghouse. There is no
difference between these two types of metal product recovery systems
relative to the kinds of waste that can be treated; the difference is in
a facility's preference relative to product purity. In the former case,
the direct condensation of metals, while more costly, allows for the
separation and collection of metals in a relatively uncontaminated form;
in the latter case, the metals are collected as a combination of several
metal oxides. If necessary, this combination of metal oxides could be
further processed to produce individual metal products of increased
purity.
(b) Less Volatile Treatment Residuals. The fraction of the
waste that is not originally volatilized has three possible
dispositions: (1) the material is such that it can be used directly as a
product (e.g., a waste residual containing mostly metallic iron can be
reused directly in steel making); (2) the material can be reused after
further processing (e.g., a waste residual containing oxides of iron,
chromium, and nickel can be reduced to the metallic form and then
81
-------
recovered for use in the manufacture of stainless steel); and (3) the
material has no recoverable value and is land disposed as a slag.
(3) Description of high temperature metals recovery process. The
process essentially consists of four operations: (1) a blending operation
to control feed parameters, (2) high temperature processing, (3) a
product collection system, and (4) handling of the less volatile treated
residuals. A generic schematic diagram for high temperature metals
recovery is shown in Figure 3-2.
(a) Blending operation. For the system shown, variations in
feeds are minimized by blending wastes from different sources. Prior to
feeding the kiln, fluxing agents are added to the waste. Carbon is also
added to the waste as required. The fluxes (limestone or sand) are added
to react with certain waste components, preventing their volatilization,
thus improving the purity of the desired metals recovered. In addition,
the moisture content is adjusted by either adding water or blending
various wastes.
(b) High temperature processing. These materials are fed to
the furnace where they are heated and the chemical reactions take place.
The combination of residence time and turbulence helps ensure maximum
volatilization of metal constituents.
(c) Product collection. As discussed previously, the product
collection system can consist of either a condenser or a combination
condenser and baghouse. As noted earlier, the particular system depends
on whether the metal is to be collected in the metallic form or as an
oxide.
82
-------
F006
(Sludgt)
CARBON
^
FLUXES
(ADDITIVES)^
FEED
BLENDING
>
HIGH
TEMPERATURE
PROCESSING
PRODUCT
COLLECTION
REUSE
00
CO
RESIDUAL
COLLECTION
I
REUSE OR
LAND DISPOSAL
FIGURE 3-2 EXAMPLE HIGH TEMPERATURE METALS RECOVERY SYSTEM
-------
(d) Handling of less volatile treatment residuals. The
equipment needed to handle the less volatile metal treated residuals
depends on the final disposition of the material. If further recovery
were performed, then the waste would be treated in another furnace. If
the material were to be land disposed, the final process step would
generally consist of quenching.
(4) Waste characteristics affecting performance In determining
whether high temperature metals recovery technologies are likely to
achieve the same level of performance on an untested waste as on a
previously tested waste, EPA will examine the following three waste
characteristics that have an impact on treatability: (1) type and
concentrations of metals in the waste, (2) relative volatility of the
metals, and (3) heat transfer characteristics of the waste.
(a) Type and concentrations of metals in the waste. Because
this is a metals recovery process, the product must meet certain
requirements for recovery. If the waste contains other volatile metals
that are difficult to separate and whose presence may affect the ability
to refine the product for subsequent reuse, high temperature metals
recovery may provide less effective treatment. Analytical methods for
metals can be found in SW-846.
(b) Boiling point. The relative volatilities of the metals in
the waste also affect the ability to separate various metals. There is
no conventional measurement technique for determining the relative
volatility of a particular constituent in a given waste. EPA believes
that the best measure of volatility of a specific metal constituent is
84
-------
the boiling point. EPA recognizes that the boiling point has certain
shortcomings, primarily the fact that although boiling points are given
for pure components, the other constituents in the waste will affect
partial pressures and, thus, will affect the boiling point of the
mixture. EPA has not identified a parameter that can better assess
relative volatility. Boiling points of metals can be determined from the
literature.
(c) Heat transfer characteristics. The ability to heat
constituents within a waste matrix is a function of the heat transfer
characteristics of a heterogeneous waste material. To be volatilized and
recovered, the constituents being recovered from the waste must be heated
near or above their boiling points. Whether sufficient heat will be
transferred to the particular constituent to cause the metal to
volatilize will depend on the heat transfer characteristics of a waste.
There is no conventional direct measurement of the heat transfer
characteristics of a waste. EPA believes that the best measure of heat
transfer characteristics of the waste is thermal conductivity. The
analytical method that EPA has identified for measurement of thermal
conductivity is named "Guarded, Comparative, Longitudinal Heat Flow
Technique"; it is described in Appendix D.
(5) Design and operating parameters The parameters that EPA will
evaluate when determining whether a high temperature metals recovery
system is well designed and well operated are (1) the furnace
temperature, (2) the furnace residence time, (3) the amount and ratio of
the feed blending materials, and (4) mixing. Below is an explanation of
85
-------
why EPA believes these parameters are Important to an analysis of the
design and operation of the system.
(a) Furnace Temperature. For sufficient heat to be transferred
to the waste for volatilization, high temperatures must be provided. The
higher the temperature in the furnace, the more likely the constituents
are to react with carbon to form free metals and volatilize. The
temperature must be approximately equal to or greater than the boiling
point of the metals being volatilized. Excessive temperatures could
volatilize unwanted metals into the product, possibly inhibiting the
potential for reuse of the volatilized product. In assessing performance
during the treatment period, EPA would want continuous temperature data.
(b) Furnace Residence Time. Furnaces must be designed to
ensure that the waste has sufficient time to be heated to the boiling
point of the metals to be volatilized. The time necessary for complete
volatilization of these constituents is dependent on the furnace
temperature and the heat transfer characteristics of the waste. The
residence time is a function of the physical dimensions of the furnace
(length, diameter, and slope (for rotary kilns)), the rate of rotation
(if applicable), and the feed rate.
(c) Amount and Ratio of Feed Blending Materials. For the
maximum volatilization of the metals being recovered, the following feed
parameters must be controlled by the addition of carbon, fluxes, and
other agents if necessary. Blending of these feed components is also
86
-------
needed to adjust the following feed parameters to the required volume:
carbon content, moisture content, calcium-to-silica ratio, and initial
concentration of the metals to be recovered. These parameters all affect
the rate of the reduction reaction and volatilization. EPA will examine
blending ratios during treatment to ensure that they comply with design
conditions.
(d) Mixing. Effective mixing of the total components is
necessary to ensure that a uniform waste is being treated. Turbulence in
the furnace also ensures that no "pockets" of waste go untreated.
Accordingly, EPA will examine the type and degree of mixing involved when
assessing treatment design and performance.
3.4 Performance Data
For treatment of F006 nonwastewaters, EPA has 56 treated and
untreated data pairs for 8 BOAT list metals using stabilization. For the
untreated waste, EPA has total constituent and TCLP leachate data; for
the treated waste, EPA has TCLP leachate data. These data were submitted
to EPA by industry. The data represent wastes from a range of
electroplating industries including automotive part manufacturing,
aircraft overhauling, zinc plating, small engine manufacturing, circuit
board manufacturing, and four wastes identified as F006 but not
specifically characterized. Table 3-2 presents these data, and a
discussion of how EPA used these data in the development of the BOAT
treatment standards can be found in Sections 4, 5, and 6. The additional
data that are not presented in this section can be found in Appendix C.
87
-------
1975g
Table 3-2 Performance Data for Raw and Stabilized F006 Wastes
Metal Concentrations (ppm)
Mix*
Source Ratio
Unknown
Unstabilized
As received
TCLP
Stabilized
TCLP 0.2
Autopart manufacture
Unstabiltzed
As received
TCLP
Stabilized
TCLP 0.2
TCLP 0.5
Aircraft overhaul facility
Unstabilized
As received
TCLP
Stabilized
TCLP 0.2
TCLP 0.5
Zinc plattng
Unstabilized
As received
TCLP
Stabilized
TCLP 0.2
TCLP 1.0
Unknown
Unstabiltzed
As received
TCLP
Stabi lized
TCLP 0.2
TCLP 0.5
Barium Cadmium
31.3
2.21
0.50
0.01
85.5 67.3
1.41 1.13
0.33 0.06
0.31 0.02
1.31
0.02
0.01
<0.01
14.3 720
0.38 23.6
0.31 3.23
0.23 0.01
Chromium Copper Lead
755 7030 409
0.76 368 10.7
0.40 5.4 0.40
0.39 0.25 0.36
716 257
0.43 2.26
0.08 0.30
0.20 - 0.41
1510 88.5
4.62 0.45
0.30 0.30
0.15 0.21
12200 160 52
25.3 1.14 0.45
0.25 0.20 0.24
0.30 0.27 0.34
Nickel
435
0.71
0.04
989
22.7
1.5
0.03
259
1.1
0.23
0.15
374
0.52
0.10
0.02
701
9.78
0.53
0.03
Silver
6.62
0.14
0.03
0.05
38.9
0.20
0.20
0.05
9.05
0.16
0.03
0.03
5.28
0.08
0.04
0.04
Zinc
1560
0.16
0.03
4020
219
36.9
0.01
631
5.41
0.05
0.03
90200
2030
32
0.01
35900
867
3.4
0.04
-------
1975g
Table 3-2 (continued)
00
vo
Mix
Source Ratio
Small engine manufacture
Unstabi lized
As received
TCLP
Stabilized
TCLP 0.2
TCLP 0.5
Circuit board manufacture
Unstabi lized
As received
TCLP
Stabilized
TCLP 0.2
TCLP 0.5
Unknown
Unstabi lized
As received
TCLP
Stabilized
TCLP 0.2
TCLP 0.5
Unknown
Unstabi lized
As received
TCLP
Stabi lized
TCLP 0.2
TCLP 0.5
Barium Cadmium Chromium Copper
7.28 3100 1220
0.3 38.7 31.7
0.02 0.21 0.21
0.01 0.38 0.29
5.39 42900 10600
0.06 360 8.69
0.01 3.0 0.40
0.01 1.21 0.42
15.3 5.81 17600
0.53 0.18 483
0.32 0.01 0.50
0.27 0.01 0.32
19.2 - --- 27400
0.28 16.9
0.19 - 3.18
0.08 0.46
Lead
113
3.37
0.30
0.36
156
1.0
0.30
0.38
1.69
4.22
0.31
0.37
24500
50.2
2.39
0.27
Nickel
19400
730
16.5
0.04
13000
152
0.40
0.10
23700
644
15.7
0.04
5730
16.1
1.09
0.02
Silver Zinc
4.08 27800
0.12 1200
0.03 36.3
0.06 0.03
12.5 120
0.05 0.62
0.03 0.02
0.05 0.02
8.11 15700
0.31 650
0.03 4.54
0.05 0.02
322
1.29
0.07
<0.01
Mi-x ratio * weight of reagent
waste of waste
Source: CWM, 1987. Chemical Waste Management Report No. 87-117.
-------
EPA had other performance data from EPA's delisting program. These
data consisted of 15 treated and untreated data sets for cadmium,
chromium, lead, and nickel. These data are not presented here because
they represent EP toxicity test results. The BOAT program is not using
EP toxicity test results as a measure of treatment performance for
stabilization (immobilization) technologies. These data can be found in
the Administrative Record.
90
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4. IDENTIFICATION OF BEST DEMONSTRATED AVAILABLE TECHNOLOGY
In this section, EPA explains Its determination of which technology
represents the "best" level of performance in addition to being
demonstrated and available. As discussed in Section 3, the demonstrated
treatment technologies are stabilization, metals recovery, and
vitrification.
Of the technologies identified as demonstrated, EPA has determined
that the level of performance achieved by stabilization represents best
demonstrated available technology (BOAT) for F006 nonwastewaters. EPA's
rationale for this determination is presented below.
As stated, the demonstrated technologies are stabilization,
vitrification, and high temperature metals recovery. Of the three
demonstrated technologies, EPA has performance data only on
stabilization. EPA does not expect that vitrification, in the absence of
data to the contrary, would achieve a better level of performance than
stabilization because the underlying principles of operation are
essentially the same. Section 3.3 discusses the underlying principles of
stabilization.
With regard to high temperature metals recovery, EPA would expect
this technology to achieve a better level of performance for those F006
wastes where high temperature metals recovery is demonstrated. First of
all, this treatment system reduces the total metal concentration, which
stabilization is not designed to do. Additionally, treatment residuals
generated following the application of the high temperature metals
91
-------
recovery process are generally found to leach metals at lower
concentrations than stabilized materials. While EPA's methodology for
BOAT would require treatment standards based on high temperature metals
recovery, EPA did not use this technology as the basis for BOAT standards
because insufficient data exist to clearly delineate the F006 wastes for
which high temperature metals recovery is demonstrated. EPA is in the
process of collecting data and information that may be used by the Agency
in determining whether a separate treatability group could be established.
In addition to determining that stabilization represents the "best"
level of performance for all F006 wastes, EPA has also shown this
technology to be demonstrated and has determined it to be available
(i.e., the technology provides substantial treatment and is commercially
available). EPA's determination of substantial treatment is discussed
below.
As a first step in determining substantial treatment, EPA examined
the data to determine if any data represented treatment by a poorly
designed or poorly operated system. This screening step resulted in the
deletion of 54 data points -- 4 for barium, 7 for cadmium, 5 for
chromium, 7 for copper, 8 for lead, 8 for nickel, 7 for silver, and 8 for
zinc -- because the data points showed that the binder-to-waste ratio was
not properly designed. Presented in Table 4-1 are the remaining data
that show substantial treatment. These data were used in the second step
of the screening procedure to adjust for the analytical recoveries.
92
-------
Errata - Table 4-1 for BOAT Background Document for FOGS
F006 TCLP Data Showing Substantial Treatment (mg/1)
^
Manufacturing Mix ..
Source ratio Barium Cadmium Chromium Copper Lead Nickel
Unknown
.-3,-, - - - - - 0 71
raw u . / i
..i A *9 t\ f\A
treated 0.2 u.04
Auto part manufacture
raw - 2.21 0.75 363 10.7 22.7
treated 0.5 0.01 0.29 0.25 0.25 0.03
Aircraft overhaul facility
raw 1.41 1.13 0.43 2.25 1.1
lan * » .
treated - 0-2 0.33 0.05 0.08 - 0.30 0.23
Zinc plating , .
raw - ' 0.02 4.62 % 0.45 0.52
idH
treated 1-0 <0-01 ' °'15 °'21 °'02
Unknown
raw 0.23 22.5 25,3 1.14 0.4S 9.78
1 Q W
t^^d 0.5 0-22 0.01 0.30 0.27 0.24 Q.Q3
Small engine manufacture
0.03 38.7 31.7 3.37 730
raw
, n <; 0 01 0.38 0.29 0.35 0.04
treated o.a u-ut
Circuit board manufacture
0 OS 360 8.69 *l.O 152
raw u-u
f r ^ OS 0.01 1.21 0.42 0.25 0.10
treated u-3
Unknown
O.S2 0.18 483 4.22 644
treated 0-5 0..*7 0.01 ' °-X °'37 °-04
UnknOV*^ M»"VJ W , ^{ \J . \Jf,
treated 0.5 O.w3
Silver Zinc
0.16
0.03
r.i'
1-
0.14 219
O.OS 0.01
0.20 5.41
0.2Q 0.05
0.16 "2030 -
0.03 0.01
O.C3 867
O.G4 0.04
0.12 1200
O.OS 0.03
O.OS 0.62
O.OS 0-02
0.21 6SO
O.OS 0.02
1.29
<0.01
-------
1951g
Table 4-1 F006 TCLP Data Showing Substantial Treatment (mg/1)
Manufacturing
Source
Unknown
raw
treated
Auto part manufacture
raw
treated
Aircraft overhaul facility
raw
treated
Zinc plating
raw
treated
Unknown
raw
treated
Small engine manufacture
raw
treated
Circuit board manufacture
raw
treated
Unknown
raw
treated
Unknown
raw
treated
Mix
ratio Barium Cadmium Chromium
0.2
2.21 0.76
0.5 0.01 0.39
1.41 1.13 0.43
0.2 0.33 0.06 0.08
0.02
1.0 <0.01
0.38 23.6 25.3 1.14
0.5 0.23 0.01 0.30
0.03 38.7
0.5 0.01 0.38
0.06 360
0.5 0.01 1.21
0.53 0.18
0.5 0.27 0.01
0.28
0.5 0.08
Copper
-
368
0.25
-
4.62
0.15
0.45
0.27
31.7
0.29
8.69
0.42
483
0.32
16.9
0.46
Lead
-
10.7
0.36
2.26
0.30
0.45
0.21
9.78
0.34
3.37
0.36
1.0
0.38
4.22
0.37
50.2
0.27
Nickel
0.71
0.04
22.7
0.03
1.1
0.23
0.52
0.02
0.08
0.03
730
0.04
152
0.10
644
0.04
16.1
0.02
Silver Zinc
0.16
0.03
0.14 219
0.05 0.01
0.20 5.41
0.20 0.05
0.16 2030
0.03 0.01
867
0.04 0.04
0.12 1200
0.06 0.03
0.05 0.62
0.05 0.02
0.31 650
0.05 0.02
1.29
<0.01
-------
After this step, the Agency examined the remaining treated values and
adjusted the data using the analytical recovery values. (See Appendix B
for analytical recovery data.)
EPA's determination of substantial treatment is based on the
following observations for reductions in the TCLP leachate's
concentration. Cadmium is shown to be reduced from as much as 23.6 mg/1
to 0.01 mg/1, chromium from 360 to 1.21 mg/1, copper from 483 mg/1 to
0.32 mg/1, lead from 50.2 mg/1 to 0.27 mg/1, nickel from 730 to
0.04 mg/1, silver from 0.31 to 0.05 mg/1, and zinc from 2030 to 0.01 mg/1.
The Agency believes the reduction in the range and magnitude of these
hazardous constituents to be substantial. Stabilization has been
determined to be demonstrated and best, has provided substantial
treatment, and is commercially available; therefore, stabilization
represents BOAT for F006 nonwastewaters.
94
-------
5. SELECTION OF REGULATED CONSTITUENTS
As discussed in Section 1, the Agency has developed a list of
hazardous constituents (Table 1-1) from which the constituents to be
regulated are selected. Tne list is a "growing list" that does not
preclude the addition of new constituents as additional key data or
information becomes available. The list is divided into the following
nine categories: volatile organics, semi volatile organics, metals,
inorganics other than metals, organochlorine pesticides, phenoxyacetic
acid herbicides, organophosphorous pesticides, PCBs, and dioxins and
furans. Also discussed in Section 1 is EPA's process for selecting
constituents to be regulated. In general, this process consists of
identifying constituents in the untreated waste that are present at
treatable concentrations and then regulating all of the constituents
necessary to ensure effective treatment. Below is a discussion that
details how EPA arrived at the list of constituents to be regulated for
F006.
Of the 232 constituents in the BOAT list, EPA has analytical data for
37 volatile organics and 11 out of 15 BOAT list metals. Table 5-1
summarizes which of the 232 constituents were analyzed and were
detected. EPA would not expect any of the four metals for which the
Agency does not have analytical data to be present in the F006 wastes.
Of the 137 BOAT list organics not analyzed, EPA is not aware that any of
these constituents that are used in the electroplating process;
therefore, EPA would not expect these constituents to be present at
treatable levels. Similarly, EPA would not expect 20 organochlorine
95
-------
1972g
Table 5-1. List of BOAT Constituents Found in F006 Waste
BOAT
reference
no.
222.
1.
2.
3.
4.
5.
6.
223.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
25.
26.
27.
28.
29.
224.
225.
226.
30.
227.
31.
214.
32.
Parameter
Volatiles
Acetone
Acetonitrile
Acrolein
Acrylonitrile
Benzene
Bromodichloromethane
Bromomethane
n-8utyl alcohol
Carbon tetrachloride
Carbon disulfide
Chlorobenzene
2~Chloro-l,3-butadiene
Chlorodibromomethane
Chloroethane
2-Chloroethyl vinyl ether
Chloroform
Chloromethane
3-Chloropropene
l,2-Dibromo-3-chloropropane
1,2-Oibromoethane
Dibromomethane
Trans-1.4-Dichloro-2-butene
Dichlorodifluoromethane
1,1-Dichloroethane
1,2-Oichloroethane
1,1-Dicnloroethylene
Trans- 1. 2-0 ichloroethene
1,2-Dichloropropane
Trans-1 ,3-Dichloropropene
cis-l,3-0ichloropropene
1.4-Oioxane
2-£thoxyethanol
Ethyl acetate
Ethyl benzene
Ethyl cyanide
Ethyl ether
Ethyl methacrylate
Ethylene oxide
lodomethane
CAS no.
67-64-1
75-05-8
107-02-8
107-13-1
71-43-2
75-27-4
74-83-9
71-36-3
56-23-5
75-15-0
108-90-7
126-99-8
124-48-1
75-00-3
110-75-8
67-66-3
74-87-3
107-05-1
96-12-8
106-93-4
74-95-3
110-57-6
75-71-8
75-34-3
107-06-2
75-35-4
156-60-5
76-87-5
10061-02-6
10061-01-5
123-91-1
110-80-5
141-78-6
100-41-4
107-12-0
60-29-7
97-63-2
75-21-8
74-88-4
Status*
ND
NA
NO
NO
NO
ND
NO
NO
ND
ND
NO
ND
ND
NO
NO
NO
NO
NA
NA
NA
NA
NA
NA
ND
ND
NO
NA
NO
NA
NO
NA
NA
NA
ND
NA
NA
NA
NA
NA
96
-------
1972g
Table 5-1 (continued)
BOAT
reference
no.
33.
228.
34.
229.
35.
37.
38.
230.
39.
40.
41.
42.
43.
44.
45.
46.
47.
48.
49.
231.
50.
215.
216.
217.
51.
52.
53.
54.
55.
56.
57.
58.
59.
218.
60.
61.
62.
Parameter
Volatiles (continued)
Isobutyl alcohol
Methanol
Methyl ethyl ketone
Methyl isobutyl ketone
Methyl methacrylate
Methacrylonitrile
Methylene chloride
2-Nitropropane
Pyridine
1,1,1, 2-Tet rach loroethane
1,1.2,2-Tetrachloroethane
Tetrachloroethene
Toluene
Tribromomethane
1.1,1-Trichloroethane
1,1,2-Trich loroethane
Trichloroethene
Trichloromonof luoromethane
1,2, 3-Tr ichloropropane
l,1.2-Trich1oro-l,2,2-
trif luoroethane
Vinyl chloride
1,2-Xylene
1,3-Xylene
1,4-Xylene
Semivolat i les
Acenaphthalene
Acenaphthene
Acetophenone
2-Acetylaminof luorene
4-Aminobiphenyl
Aniline
Anthracene
Aramite
Benz(a)anthracene
Benzal chloride
Benzenethiol
Deleted
Benzo(a)pyrene
CAS no.
78-83-1
67-56-1
78-93-3
108-10-1
80-62-6
126-98-7
75-09-2
79-46-9
110-86-1
630-20-6
79-34-6
127-18-4
108-88-3
75-25-2
71-55-6
79-00-5
79-01-6
75-69-4
96-18-4
76-13-1
75-01-4
97-47-6
108-38-3
106-44-5
208-96-8
83-32-9
96-86-2
53-96-3
92-67-1
62-53-3
120-12-7
140-57-8
56-55-3
98-87-3
108-98-5
--
50-32-8
Status*
NA
NA
NA
NA
NA
NA
NO
NA
NA
NA
NO
NO
NO
NA
ND
NO
ND
NA
NA
NA
ND
NO
ND
ND
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
97
-------
1972g
Table 5-1 (continued)
BOAT
reference
no.
63.
64.
65.
66.
67.
68.
69.
70.
71.
72.
73.
74.
75.
76.
77.
78.
79.
80.
81.
82.
232.
83.
84.
85.
86.
87.
66.
89.
90.
91.
92.
93.
94.
95.
96.
97.
98.
99.
100.
101.
Parameter
Semivolatiles (continued)
6enzo(b)f luoranthene
6enzo(ghi )pery lene
Benzo(k)f luoranthene
p-Benzoqulnone
Bis(2-chloroethoxy)methane
Bis(2-chloroethyl)ether
Bis(2-chloroisopropyl)ether
Bis(2-ethylhexyl)phthalate
4-Bromophenyl phenyl ether
Butyl benzyl phthalate
2-sec-Butyl-4,6-dinitrophenol
p-Chloroaniline
Chlorobenrilate
p-Chloro-m-cresol
2-Chloronaphthalene
2-Chlorophenol
3-Chloropropionitri le
Chrysene
ortho-Cresol
para-Cresol
Cyc lohexanone
Dibenz(a,h)anthracene
Dibenzo(a.e)pyrene
Oibenzo(a, i)pyrene
m-D ich lorobenzene
o-Dichlorobenzene
p-D ich lorobenzene
3.3'-Dichlorobenzidine
2,4-Dichlorophenol
2,6-Dichlorophenol
Diethyl phthalate
3, 3 ' -Oimethoxybenzidine
p- D i met hy 1 am i noazobenzene
3,3'-01methylbenzidine
2,4-Dimetnylphenol
Dimethyl phthalate
Di-n-butyl phthalate
1,4-Dinitrobenzene
4,6-Dinitro-o-cresol
2,4-Oinitrophenol
CAS no.
205-99-2
191-24-2
2Q7-08-9
106-51-4
111-91-1
111-44-4
39638-32-9
117-81-7
101-55-3
85-68-7
88-85-7
106-47-8
510-15-6
59-50-7
91-58-7
95-57-8
542-76-7
218-01-9
95-48-7
106-44-5
108-94-1
53-70-3
192-65-4
189-55-9
541-73-1
95-50-1
106-46-7
91-94-1
120-83-2
87-65-0
84-66-2
119-90-4
60-11-7
119-93-7
105-67-9
131-11-3
84-74-2
100-25-4
534-52-1
51-28-5
Status*
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
98
-------
1972g
Table 5-1 (continued)
BOAT
reference
no.
102.
103.
104.
105.
106.
219.
107.
108.
109.
110.
111.
112.
113.
114.
115.
116.
117.
118.
119.
120.
36.
121.
122.
123.
124.
125.
126.
127.
128.
129.
130.
131.
132.
133.
134.
135.
136.
137.
138.
Parameter
Semivolatiles (continued)
2,4-Oinitrotoluene
2.6-Dinitrotoluene
Di-n-octyl phthalate
Di-n-propylnitrosamine
Dlphenylamine
0 1 pheny 1 n 1 1 rosami ne
1.2-Diphenylhydrazine
Fluoranthene
Fluorene
Hexach 1 orobenzene
Hexach lorobutad 1 ene
Hexach lorocyc lopentad i ene
Hexachloroethane
Hexach lorophene
Hexach loropropene
lndeno(l,2,3-cd)pyrene
Isosafrole
Methapyrilene
3-Methylcholanthrene
4,4'-Methylenebis
(2-chloroaniline)
Methyl methanesulfonate
Naphthalene
1 , 4-Naphthoqu i none
l-Naphthylamine
2-Naphthylamine
p-Nitroaniline
Nitrobenzene
4-Nitrophenol
N-Nitrosodi-n-butylamine
N-Nitrosodiethylamine
N-Nitrosodimethylamine
N-Nitrosomethylethylamine
N-Nitrosomorpholine
N-Nitrosopiperidine
n-Nitrosopyrrolidine
5-Nitro-o-toluidine
Pentachlorobenzene
Pentach loroethane
Pentach 1 oron i t robenzene
CAS no.
121-14-2
606-20-2
117-84-0
621-64-7
122-39-4
86-30-6
122-66-7
206-44-0
86-73-7
118-74-1
87-68-3
77-47-4
67-72-1
70-30-4
1888-71-7
193-39-5
120-58-1
91-80-5
56-49-5
101-14-4
66-27-3
91-20-3
130-15-4
134-32-7
91-59-8
100-01-6
98-95-3
100-02-7
924-16-3
55-18-5
62-75-9
10595-95-6
59-89-2
100-75-4
930-55-2
99-65-8
608-93-5
76-01-7
82-68-8
Status*
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
99
-------
1972g
Table 5-1 (continued)
BOAT
reference
no.
139.
140.
141.
142.
220.
143.
144.
145.
146.
147.
148.
149.
150.
151.
152.
153.
154.
155.
156.
157.
158.
159.
221.
160.
161.
162.
163.
164.
165.
166.
167.
168.
169.
170.
171.
Parameter
Semivolati les (continued)
Pentach loropheno 1
Phenacetin
Phenanthrene
Phenol
Phthalic anhydride
2-Picoline
Pronamide
Pyrene
Resorcinol
Safrole
1 ,2,4,5-Tetrachlorobenzene
2,3,4,6-Tetrachlorophenol
1,2,4-Trichlorobenzene
2.4,5-Trichlorophenol
2 , 4 , 6-Tr ich loropheno 1
Tr i s ( 2 . 3-d i bronwpropy 1 )
phosphate
Metals
Ant imony
Arsenic
Barium
Beryllium
Cadmium
Chromium (total)
Chromium (hexavalent)
Copper
Lead
Mercury
Nickel
Selenium
Silver
Thallium
Vanadium
Zinc
Inorganics
Cyanide
Fluoride
Sulfide
CAS no.
87-86-5
62-44-2
85-01-8
108-95-2
85-44-9
109-06-8
23950-58-5
129-00-0
108-46-3
94-59-7
95-94-3
58-90-2
120-82-1
95-95-4
88-06-2
126-72-7
7440-36-0
7440-38-2
7440-39-3
7440-41-7
7440-43-9
7440-47-32
-
7440-50-8
7439-92-1
7439-97-6
7440-02-0
7782-49-2
7440-22-4
7440-28-0
7440-62-2
7440-66-6
57-12-5
16964-48-8
8496-25-8
Status*
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
0
0
NA
D
0
NA
D
0
0
D
0
D
NA
NA
0
D
NA
NA
1UO
-------
1972g
Table 5-1 (continued)
BOAT
reference
no.
172.
173.
174.
175.
176.
177.
178.
179.
180.
181.
182.
183.
184.
185.
186.
187.
188.
189.
190.
191.
192.
193.
194.
195.
196.
197.
198.
199.
200.
201.
202.
Parameter
Orqanochlorinej pesticides
Aldrln
alpha-BHC
beta-BHC
delta-BHC
ganroa-BHC
Chlordane
ODD
DDE
DDT
Dleldrin
Endosulfan I
Endosulfan II
Endrin
Endrin aldehyde
Heptachlor
Heptachlor epoxlde
Isodrln
Kepone
Methoxyc lor
Toxaphene
Phenoxvacetic acid herbicides
2.4-Dichlorophenoxyacetic acid
Silvex
2,4,5-T
OraanoohosDhorous insecticides
Disulfoton
Famphur
Methyl parathion
Parathion
Phorate
PCBs
Aroclor 1016
Aroclor 1221
Aroclor 1232
CAS no.
309-00-2
319-84-6
319-85-7
319-86-8
58-89-9
57-74-9
72-54-8
72-55-9
50-29-3
60-57-1
939-98-8
33213-6-5
72-20-8
7421-93-4
76-44-8
1024-57-3
465-73-6
143-50-0
72-43-5
8001-35-2
94-75-7
93-72-1
93-76-5
298-04-4
52-85-7
298-00-0
56-38-2
298-02-2
12674- if -2
11104-28-2
11141-16-5
Status*
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
101
-------
1972g
Table 5-1 (continued)
BOAT
reference
no.
Parameter
CAS no.
Status*
PCBs (continued)
203.
204.
205.
206.
Aroclor 1242
Aroclor 1248
Aroclor 1254
Aroclor 1260
53469-21-9
12672-29-6
11097-69-1
11096-82-5
NA
NA
NA
NA
Dioxins and furans
207.
208.
209.
210.
211.
212.
213.
Hexacnlorodibenzo-p-dioxins
Hexachlorodibenzofurans
Pentachlorodibenzo-p-dioxins
Pentachlorodibenzofurans
Tetracnlorodibenzo-p-dioxins
Tetrachlorodibenzofurans
2,3,7,8-Tetrachlorod i benzo-
p-dioxin
1746-01-6
NA
NA
NA
NA
NA
NA
NA
NO - Not detected
D - Detected
NA - Not analyzed
102
-------
pesticides, 3 phenoxyacetic acid herbicides, 5 organophosphorous
insecticides, 7 PCBs, and 7 dioxins and furans to be present in F006
waste; hence, the Agency would not expect any of these to be present at
treatable levels.
None of the organics shown in Table 5-1 were present at treatable
concentrations. The highest of all the organics was acetone at 130 ppb.
Of the 11 metals detected in F006, EPA has treatment performance data for
8. EPA is regulating seven of these metals: cadmium, chromium, copper,
lead, nickel, silver, and zinc. EPA is not regulating barium. For
antimony, arsenic, selenium, and cyanide, EPA does not have treatment
performance data and therefore, is not proposing regulations for these
constituents. As data become available, EPA will develop standards for
these constituents.
103
-------
6. CALCULATION OF BOAT TREATMENT STANDARDS
Section 4 presents EPA's rationale for determining best demonstrated
available technology for F006. As discussed, EPA has determined that
stabilization represents BOAT for F006 nonwastewaters. In this section,
EPA presents its determination of treatment standards using the
performance data shown in Section 3 and again presented in Section 4 as
part of EPA's determination of substantial treatment.
As discussed in Section 3, EPA's methodology requires the Agency to
first delete any performance data that does not represent a well-designed
and well-operated treatment system. EPA previously performed this
analysis in Section 4; as noted, EPA found 54 data points that did not
represent a well-designed treatment system. All of these data were
deleted because of a poor design value for the binder-to-waste ratio.
Following this screening procedure, EPA corrected all of the
remaining data for analytical recoveries using the accuracy correction
factors shown in Appendix B.
Using the accuracy-corrected data, EPA developed treatment standards
by averaging the performance data for each constituent and then
multiplying the average value by a variability factor that accounts for
variations in technology performance, waste characteristics, and
laboratory analysis. This procedure is consistent with the Agency's
methodology as detailed in Section 1.
104
-------
Table 6-1 shows the calculations for the seven metals regulated for
F006 nonwastewaters. These standards represent instantaneous maximum
concentrations that must be achieved as a prerequisite for land
disposal. The concentrations are in mg/1 (parts per million on a weight
per volume basis), and represent values for the TCLP leachate. EPA is
not proposing treatment standards representing total concentration. As
discussed in Section 3, EPA has requested data and information concerning
the use of high temperature metals recovery; depending on the type and
quality of data received, EPA may in the future propose total composition
standards for all or part of the F006 constituents.
105
-------
1670g/p 26
Table 6-1 Regulated Constituents and Calculated Treatment Standards for F006
Average
N - Sample
numDers
Variabi lity
factor
Treatment
standard
Caomium
..
0.01
0.06
0.01
0.01
0.01
0.01
0.01
--
0.017
7
3.9
0.066
Chromium
..
0.46
0.09
0.35
0.44
1.4
0.55
5
6.9
3.8
Copper
..
0.27
0.16
0.29
0.31
0.45
0.35
0.50
0.33
7
2.2
0.71
Lead
..
0.39
0.34
0.23
0.37
0.39
0.41
0.40
0.29
0.35
8
1.5
0.53
Nickel
0.04
0.03
0.26
0.02
0.03
0.04
0.11
0.04
0.02
0.066
9
4.7
0.31
Silver
..
0.06
0.24
0.04
0.05
0.07
0.06
0.06
0.063
7
3.1
0.26
Zinc
0.03
0.01
0.05
0.01
0.04
0.03
0.02
0.02
0.01
0.024
9
3.6
0.086
106
-------
References
Ajax Floor Products Corp. n.d. Product literature: technical data
sheets on hazardous waste disposal system. Ajax Floor Products Corp.,
P.O. Box 161, Great Meadows, N.J. 07838.
Austin, G.T. 1984. Shreve's chemical process industries. 5th ed.
New York: McGraw-Hill.
Bishop, P.L., Ransom, S.B., and Grass, D.L. 1983. Fixation Mechanisms
in solidification/stabilization of inorganic hazardous wastes. In
Proceedings of the 38th Industrial Waste Conference, May 10-12, 1983,
at Purdue University, West Lafayette, Indiana.
Center for Metals Production, Electric arc furnace dust-disposal. recycle
and recovery. Pittsburgh, PA: May 1985.
Conner, J.R. 1986. Fixation and solidification of wastes. Chem. Enq.
Nov. 10, 1986.
Cull inane, M.J., Jr., Jones, L.W., and Malone, P.G. 1986. Handbook for
stabilization/solidification of hazardous waste. U.S. Army Engineer
Waterways Experiment Station. EPA report No. 540/2-86/001.
Cincinnati, Ohio: U.S. Environmental Protection Agency.
Duby, Paul. 1980. Extractive metallurgy, In Kirk-Othmer encyclopedia of
chemical technology. Vol. 9, p. 741.
Electric Power Research Institute. 1980. FGD sludge disposal manual.
2nd ed. Prepared by Michael Baker Jr., Inc. EPRI CS-1515 project 1685-1
Palo Alto, California: Electric Power Research Institute.
Lloyd, Thomas. 1980. Zinc compounds. Kirk-Othmer Encyclopedia of
Chemical Technology. 3rd ed. Vol. 24, p. 856.
Lloyd, Thomas, and Showak, Walter, 1980. Zinc and zinc alloys. In
Kirk-Othmer Encyclopedia of Chemical Technology. 3rd ed. Vol. 24,
p. 824.
Maczek, Helmut and Kola, Rolf, 1980. Recovery of zinc and lead from
electric furnace steelmaking dust at Berzelius. Journal of Metals,
32:53-58.
107
-------
References
(continued)
Mai one, P.G., Jones, L.W., and Burkes, J.P. Application of
solidification/stabilization technology to electroplating wastes.
Office of Water and Waste Management. SW-872. Washington, D.C.: U.S.
Environmental Protection Agency.
Mishuck, E. Taylor, D.R., Telles, R. and Lubowitz, H. 1984.
encapsulation/ fixation (E/F) mechanisms. Report No.
DRXTH-TE-CR-84298. Prepared by S-Cubed under Contract No.
DAAK11-81-C-0164.
Pojasek RB. 1979. Solid-waste disposal: solidification Chem. Enq.
86(17): 141-145.
Price, Laurence. Tensions Mount in EAF Dust Bowl. Metal Producing.
February 1986.
USEPA. 1980. U.S. Environmental Protection Agency. U.S. Army Engineer
Waterways Experiment Station. Guide to the disposal of chemically
stabilized and solidified waste. Prepared for MERL/ORD under
Interagency Agreement No. EPA-IAG-D4-0569. PB81-181505.
Cincinnati, Ohio.
108
-------
APPENDIX A
A.I F Value Determination for ANOVA Test
As noted earlier in Section 1, EPA is using the statistical method
known as analysis of variance (ANOVA) in the determination of the level
of performance that represents "best" treatment where more than one
technology is demonstrated. This method provides a measure of the
differences between data sets. If the differences are not statistically
significant, the data sets are said to be homogeneous.
If the Agency found that the levels of performance for one or more
technologies are not statistically different (i.e., the data sets are
homogeneous), EPA would average the long-term performance values achieved
by each technology and then multiply this value by the largest
variability factor associated with any of the acceptable technologies.
If EPA found that one technology performs significantly better (i.e., the
data sets are not homogeneous), BOAT would be the level of performance
achieved by the best technology multiplied by its variability factor.
To determine whether any or all of the treatment performance data
sets are homogeneous using the analysis of variance method, it is
necessary to compare a calculated "F value" to what is known as a
"critical value." (See computational table below) These critical values
are available in most statistics texts (see, for example, Statistical
Concepts and Methods by Bhattacharyya and Johnson, 1977, John Wiley
Publications, New York).
109
-------
Where the F value is less than the critical value, all treatment data
sets are homogeneous. If the F value exceeds the critical value, it is
necessary to perform a "pair wise F" test to determine if any of the sets
are homogeneous. The "pair wise F" test must be done for all of the
various combinations of data sets using the same method and equation as
the general F test.
The F value is calculated as follows:
(i) All data are natural log transformed.
(ii) The sum of the data points for each data set is computed (T.).
(iii) The statistical parameter known as the sum of the squares
between data sets (SSB) is computed:
SSB =
"
k
I
.
TI
n *
ni
> f
.
'
.
' k
I Ti
i=l
N
2 -
j
where :
k = number of treatment technologies
n, = number of data points for technology i
N * number of data points for all technologies
TJ = sum of natural logtransformed data points for each technology.
(iv) The sum of the squares within data sets (SSW) is computed:
SSW
where:
i i
k f T-2
-1 -
Xj j = the natural logtransformed observations (j) for treatment
technology (i).
(v) The degrees of freedom corresponding to SSB and SSW are
calculated. For SSB, the degree of freedom is given by k-1. For SSW,
the degree of freedom is given by N-k.
110
-------
(vl) Using the above parameters, the F value Is calculated as
fol 1ows:
MSB
I F = MSW
where:
MSB = SSB/(k-l) and
MSW = SSW/(N-k).
A computational table summarizing the above parameters is shown below.
Computational Table for the F Value
Source
Between
Within
Degrees of
freedom
K-l
N-k
Sum of
squares
SSB
SSW
Mean square
MSB - SSB/k-1
MSW = SSW/N-k
F
MSB/MSW
Below are three examples of the ANOVA calculation. The first two
represent treatment by different technologies that achieve statistically
similar treatment; the last example represents a case in which one
technology achieves significantly better treatment than the other
technology.
Ill
-------
1790g
Example 1
Methylene Chloride
Steair stripping
Influent Effluent
Ug/D
I55C.OO
1290.00
1640.00
510C.OO
1450.00
4600. OC
1760.00
2400.00
4800.00
12100.00
Ug/D
10.00
10.00
10.00
12.00
10.00
10.00
10.00
10.00
10.00
10.00
Biological treatment
In(effluent) [Inleff luent)]2 Influent Effluent In(effluent)
2.30
2.30
2.30
2.48
2.30
2.30
2.30
2.30
2.30
2.30
Ug/D (^g/1)
5.29 1960.00 10.00 2.30
5.29 2568.00 10.00 2.30
5.29 1817.00 10.00 2.30
6.15 1640.00 26.00 3.26
5.29 3907.00 10.00 2.30
5.29
5.29
5.29
5.29
5.29
[ln(ef fluent)]
5.2S
5.29
5.2&
10.63
5.29
Sum:
23.18
53.76
12.46
31.79
Sample Size:
10 10
Mean:
3669 10.2
Standard Deviation:
3328.67 .63
Variability Factor:
10
2.32
.06
2378
923.04
1.15
13.2
7.15
2.48
2.49
.43
ANOVA Calculations:
.- , T,2
SSB ' 2. | _L
Hi
r k
N
SSW
MSB « SSB/U-1)
HSU * SSU/(N-k)
k ni , I k f T,2 ^
I, ,Z, x2j j - Z _1_
! j»i '-J J ! [ ni J
112
-------
1790g
Example 1 (continued)
F = MSB/HSU
wnere:
k = number of treatment technologies
n = number of data points for technology 1
N = number of natural log transformed data points for all technologies
T = sum of log transformed data points for each technology
X = the nat. log transformed observations (j) for treatment technology (i)
10. n « 5. N - 15. k - 2. T « 23.18. T = 12.46. T » 35.64. T - 1270.21
T = 537.31 T = 155.25
SSB =
537.31 155.25 1 1270.21
10
0.10
SSW = (53.76 + 31.79) -
MSB = 0.10/1 - 0.10
MSW = 0.77/13 = 0.06
F = = 1.67
0.06
5 J 15
537.31 155.2
10
+ 155_25| . Q ?j
5 j
ANOVA Table
Source
Between (B)
Witmn(W)
Degrees of
freedom
1
13
SS
0.10
0.77
MS
0.10
0.06
F
1.67
The critical value of the F test at the 0.05 significance level is 4.67. Since
the F value is less than the critical value, tne means are not significantly
different (i.e.. they are homogeneous).
Note: All calculations were rounded to two decimal places. Results may differ
depending upon the number of decimal places used in each step of the calculations.
113
-------
1790g
Example Z
Trichloroethylene
Steam striocinc Biological treatment
Influent Effluent In(effluent) [ln(eff luent)]2 Influent Effluent In(effluent) [ln(eff luent)]
Ug/1) U
.9/D («/D (,9/D
1650.00 10.00 2.30 5.29 200.00 10.00 2.30 5.29
52130.00 10.00 2.30 5.29 224.00 10.00 2.30 5.29
5000.00 10.00 2.30 5.29 134.00 10.00 2.30 5.29
1720.00 10.00 2.30 5.29 150.00 10.00 2.30 5.29
1560.00 10.00 2.30 5.29 484.00 16.25 2.79 7.78
10300.00 10.00 2.30 5.29 163.00 10.00 2.30 5.29
210.00 10.00 2.30 5.29 182.00 10.00 2.30 5.29
1600.00 27.00 3.30 10.89
204.00 85.00 4.44 19.71
160.00 10.00 2.30 5.29
Sum:
Sample Size:
26.14 72.92 - - 16.59 39.52
10 10 10 - 7 7 7
Mean:
2760 19.2 2.61 - 220 10.89 2.37
Standard Deviation
3209.6 23.7 .71 - 120.5 2.36 .19
Variability Factor
ANOVA Calculations
k ( Ti2
SSB = I, __
i=l 1 HI
. I '
SSW « Z !' x2
MSB * SSB/(k-l)
MSW » SSW/(N-k)
3.70 - - - 1.53
ll [I'M2]
'']i'(ir)
114
-------
1790g
Example 2 (continued)
F = MSB/MSy
wnere :
k = number of treatment technologies \
n = number of data points for "technology 1
N = number of data points for all technologies
T = sum of natural log transformed data points for each technology
X. = the natural log transformed observations (j) for treatment technology (i)
10. N ' 7, N = 17. k = 2. T = 26.14.
= 275.23
sse
10
275.23 ^ 1825.85
~T~ ~ir~
SSU = (72.92 + 39.52) -
MSB * 0.25/1 = 0.25
MSW = 4.79/15 = 0.32
0.32
683.30 275.23
+
10 7
16.59. T = 42.73, T* 1825.85. T = 683.30.
0.25
4.79
ANOVA Table
Source
Between! B)
Uithin(U)
Degrees of
freedom
1
15
SS
0.25
4.79
MS F
0.25 0.78
0.32
The critical value of the F test at the 0.05 significance level is 4.54. Since
the F value is less than the critical value, the means are not significantly
different (i.e.. they are homogeneous).
Note: All calculations were rounded to two decimal places. Results may differ
depending upon the number of decimal places used in each step of the calculations.
115
-------
1790g
Example 3
Chlorobenzene
Activated s'maae followea by carbon adsorption
Influent Effluent In(effluent) [ln(effluent)]
Ug/1) Ug/1)
Biological treatment
2 Influent
Ug/D
Effluent
(MS/1)
In(effluent)
In[(effluent)]
7200.00
6500.00
6075.00
3040.00
60.00
70.00
35.00
10.00
4.38
4.25
3.56
2.30
19.18
18.06
12.67
5.29
9206.00
16646.00
49775.00
14731.00
3159.00
6756.00
3040.00
1083.00
709.50
460.00
142.00
603.00
153.00
17.00
6.99
6.56
6.13
4.96
6.40
5.03
2.83
48.86
43.03
37.58
24 6C
40.96
25.30
8.01
Sum:
14.49
55.20
38.90
228.34
Sample Size:
4 4
Mean:
5703
49
3.62
14759
452.5
5.56
Standard Deviation:
1835.4 32.24
.95
16311.86
379.04
1.42
Variability Factor:
7.00
15.79
ANOVA Calculations:
SSB =
SSU *
k
Z,
i-1
' k
. i=i J
2 A 1 T k ^ 1
^^^ 1
^i I
£ i i
i*l
N
M
J
i'xz, J-fe flil
i\ lij J i=i iTtrJ
MSB - SSB/(k-l)
HSU - SSU/(N-k)
F - MSB/MSW
116
-------
1790g
Example 3 (continued)
where.
k = numoer of treatment technologies
n = number of d^ta points for technology i
N = number of data points for all technologies
T = sum of natural log transformed data points for each technology
X.. » the natural log transformed observations (j) for treatment technology (i)
N = 4. N = 7, N = 11. k = 2, T = 14.49. T = 38.90. T » 53.39. T*» 2850.49. T2 = 209.96
2
T' = 1513.21
SSB
209.96 1513.21
= 9.52
SSU * (55.20 + 228.34) -
209.96 1513.21
14.88
MSB = 9.52/1 = 9.52
MSU = 14.88/9 « 1.65
f = 9.52/1.65 = 5.77
ANOVA Table
Source
Between(B)
Within(W)
Degrees of
freedom
1
9
SS
9.53
14.89
MS
9. S3
1.65
r
5.77
The critical value of the F test at the 0.05 significance level is 5.12. Since
the F value is larger than the critical value, the means are significantly
different (i.e.. they are heterogeneous).
Note: All calculations were rounded to two decimal places. Results may differ depending
upon the number of decimal places used in each step of the calculations.
117
-------
A.2. Variability Factor
C
99
VF = Mean
where:
VF = estimate of daily maximum variability factor determined from
a sample population of daily data.
Cgg = Estimate of performance values for which 99 percent of the
daily observations will be below. Cgg is calculated using
the following equation: Cgq = Exp(y + 2.33 Sy) where y and
Sy are the mean and standard deviation, respectively, of the
logtransformed data.
Mean = average of the individual performance values.
EPA is establishing this figure as an instantaneous maximum because
the Agency believes that on a day-to-day basis the waste should meet the
applicable treatment standards. In addition, establishing this
requirement makes it easier to check compliance on a single day. The
99th percentile is appropriate because it accounts for almost all process
variability.
In several cases, all the results from analysis of the residuals from
BOAT treatment are found at concentrations less than the detection
limit. In such cases, all the actual concentration values are considered
unknown and hence, cannot be used to estimate the variability factor of
the analytical results. Below is a description of EPA's approach for
calculating the variability factor for such cases with all concentrations
below the detection limit.
It has been postulated as a general rule that a lognormal
distribution adequately describes the variation among concentrations.
Agency data shows that the treatment residual concentrations are
118
-------
distributed approximately lognormally. Therefore, the lognormal model
has been usedjroutinely in the EPA development of numerous regulations in
the Effluent Guidelines program and is being used in the BOAT program.
The variability factor (VF) was defined as the ratio of the 99th
percentile (C ) of the lognormal distribution to its arithmetic mean
(Mean).
VF = C99 {1)
Mean
The relationship between the parameters of the lognormal distribution
and the parameters of the normal distribution created by taking the
natural logarithms of the lognormally-distributed concentrations can be
found in most mathematical statistics texts (see for example:
Distribution in Statistics-Volume 1 by Johnson and Kotz, 1970). The mean
of the lognormal distribution can be expressed in terms of the
mean (») and standard deviation (a) of the normal distribution as
fol1ows:
C99 = Exp (it + 2.33*) (2)
Mean = Exp (/* + 0.5a2) (3)
Substituting (2) and (3) in (1) the variability factor can then be
expressed in terms of a as follows:
VF * Exp (2.33 a - 0.5a2) (4)
For residuals with concentrations that are not all below the
detection limit, the 99 percentile and the mean can be estimated from
the actual analytical data and accordingly, the variability factor (VF)
can be estimated using equation (1). For residuals with concentrations
119
-------
that are below the detection limit, the above equations can be used in
conjunction with the assumptions below to develop a variability factor.
Step 1: The actual concentrations follow a lognormal distribution. The
upper limit (UL) is equal to the detection limit. The lower limit (LL)
is assumed to be equal to one-tenth of the detection limit. This
assumption is based on the fact that data from well-designed and
well-operated treatment systems generally falls within one order of
magnitude.
Step 2: The natural logarithms of the concentrations have a normal
distribution with an upper limit equal to In (UL) and a lower limit equal
to In (LL).
Step 3: The standard deviation (a) of the normal distribution is
approximated by
a = [(In (UL) - In (LL)] / [(2)(2.33)] - [ln(UL/LL)] / 4.66
when LL = (0.1)(UL) then a = (InlO) / 4.66 - 0.494
Step 4: Substitution of the value from Step 3 in equation (4) yields the
variability factor, VF.
VF = 2.8
120
-------
APPENDIX B
' ANALYTICAL QA/QC
This appendix presents quality assurance/quality control (QA/QC)
information for the available performance data presented in Section 3.3
and identifies the methods and procedures used for analyzing the
constituents to be regulated. The QA/QC information includes matrix
spike recovery data that are used for adjusting the analytical results
for accuracy. The adjusted analytical results (referred to as
accuracy-corrected concentrations), in general, are used for comparing
the performance of one technology to that of another and for calculating
treatment standards for those constituents to be regulated.
B.I Accuracy Correction
The accuracy-corrected concentration for a constituent in a matrix is
the analytical result multiplied by the correction factor (the reciprocol
*
of the recovery fraction, i.e., the correction factor is 100 divided
by the percent recovery). For example, if Compound A is measured at
2.55 mg/1 and the percent recovery is 85 percent, the accuracy-corrected
concentration is 3.00 mg/1:
2.55 mg/1 x 1/0.85 = 3.00 mg/1
(analytical result) (correction factor) (accuracy-corrected
concentration)
The appropriate recovery values are selected according to the procedures
specified in Section 1.2.6.
*The recovery fraction is the ratio of (1) measured amount of
constituent in a spiked aliquot minus the measured amount of constituent
in the original unspiked aliquot to (2) the known amount of constituent
added to spike the original aliquot (refer to the Generic Quality
Assurance Project Plan for Land Disposal Restriction Program ("BOAT")).
121
-------
Table B-l presents matrix spike recovery data for the Stabilized
residuals F006 waste. Using these analytical recovery values, all the
data points were corrected for accuracy.
B.2 Methods and Procedures Employed to Generate the Data Used in
Calculating Treatment Standards
Table B-2 lists the methods used for analyzing the constituents to be
regulated in F006 waste. Host of these methods are specified in SW-846
(USEPA 1986a). For some analyses, SW-846 methods allow alternatives or
equivalent procedures and/or equipment to be used. The Agency plans to
use these methods and procedures to enforce the treatment standards for
F006 waste.
122
-------
1670g/p 14
Table 8-1 Matrix Spike Recoveries for Treated Waste
Constituent
Arsenic
Barium
Cadmium
Chromium
Copper
Lead
Mercury
Nickel
Selenium0
Silver6
Zinc
Original
amount
found
(ppm)
0.101s
0.01b
0.3737
0.2765
0.0075
2.9034
0.3494
0.2213
0.2247
0.1526
0.3226
0.2142
0.001
0.001
0.028
0.4742
0.101
0.043
0.0437
0.0344
0.0133
27.202
i
Duplicate
0.01
0.01
0.3326
0.222
0.0069
0.7555
0.4226
0.2653
0.2211
0.1462
0.3091
0.2287
0.001
0.001
0.0264
0.0859
0.12
0.053
0.0399
0.0411
0.0238
3.65
% Error
0.0
0.0
5.82
10.9
4.17
58.7
9.48
9.0
0.81
2.14
2.14
3.27
0.0
0.0
6.87
69.3
8.6
10.4
4.55
8.87
28.3
76.3
Actua 1
Spike
0.086
0.068
4.9474
5.1462
4.9010
6.5448
4.6780
4.5709
4.8494
4.9981
4.9619
4.6930
0.0034
0.0045
4.5400
4.6093
0.175
0.095
4.2837
0.081
5.0910
19.818
% Recovery
94.5
104
91.9
97.9
97.9
94.3
85.8
86.6
92.5
97.0
92.9
89.4
92
no
90.3
86.6
86
66**
64.8
0.87**
101.4
87.8
Accuracy
correction
factor*
1.06
0.96
1.09
1.02
1.02
1.06
1.17
1.15
1.08
1.03
1.08
1.12
1.09
0.91
1.11
1.15
1.16
0.96
1.18
114.9
0.99
1.14
'Accuracy correction factor = 100 * percent recovery.
"This value is not considered in the calculation for the accuracy correction factor.
aat a mix ratio of 0.5.
bat a mix ratio of 0.2
cfor a mix ratio of 0.2, correction factors of 1.16 and 1.18 were used when correcting for selenium and silver
concentrations, respectively.
Source: Memo to R. Turner, U.S. EPA/H.U.E.R.L. from Jesse R. Conner, Chemical Waste Management dated January 20. 1988.
123
-------
1847g
Table 8-2 Analytical Methods for Regulated Constituents
Analysis/methods Method Reference
Volatile Oroanics
Purge-and-trap 5030 1
Gas chromatography/mass spectrometry for
volatile organics 8240 1
Semivolatile Oraanics
Continuous liquid-liquid extraction (treated waste) 3520 1
Soxhlet extraction (untreated waste) 3540 1
Gas chromatography/mass spectrometry for semi-
volatile organics: Capillary Column Technique 8270 1
Metals
Acid digestion
Aqueous samples and extracts to be analyzed by 3010 1
inductively coupled plasma atomic emission
spectroscopy (ICP)
Aqueous samples and standards to be analyzed by 3020 1
furnace atomic absorption (AA) spectroscopy
Sediments, sludges, and soils 3050 1
Lead (AA, furnace technique) 7421 1
Zinc (ICP) 6010 1
Toxicity Characteristic Leaching Procedure (TCLP) 51 FR 40643 2
References:
1. U.S. Environmental Protection Agency. Test Methods for Evaluating Solid
Waste, SW-846. Third Edition. USEPA. Office of Solid Waste and
Emergency Response. November 1986.
2. U.S. EPA. U.S. Environmental Protection Agency, Office of Solid Wastes.
1988b. Hazardous waste management systems; land disposal restrictions;
final rule; Appendix I to Part 268 - Toxicity Leaching Procedure (TCLP).
51 FR 40643-40654. November 7. 1986.
-------
i APPENDIX C
This appendix presents Tables C-l and C-2, F006 treatment performance
data provided by two facilities treating F006 wastes. Table C-3 presents
F006 data that were not used in Section 3.5 of this report.
125
-------
1670g/p 9
Table C-l Composition Data and TCLP Data for
Lime-Stabilized F006 Waste
Constituents
Ant imony
Arsenic
Barium
Bery 11 i urn
Cadmium
Chromium (hexavalent)
Chromium (total)
Copper
Lead
Mercury
Nickel
Selenium
Silver
Thallium
Zinc
Sample
<10
2
20
<2
10
I*
3,200
90
134
<1
7,300
<10
<2
<10
68
Raw waste
Composition
(ppm)
3 Sample 3
duplicate
<10
5
45
<2
20
0.14
7,500
775
85
<1
4,900
<10
<2
<10
3,700
Treated
Sample 3
.
0.020
<0.10
-
<0.020
-
0.63
-
<0.10
<0.0002
-
<0.40
0.16
-
sludae
TCLP
(mg/1)
Sample 3
duplicate
.
0.015
0.13
-
<0.020
-
0.15
-
*0.10
<0.0002
-
<0.20
<0.020
-
Source: Table 6-13, Onsite Engineering Report for Envirite Corporation, 1986.
"I = Color interference.
126
-------
1670g/p 8
Table C-2 Composition and TCLP Data for Lime-Stabilized Phosphated SolidsF006
ro
Raw waste
Constituents
Ant imony
Arsenic
Barium
Beryllium
Cadmium
Chromium (hexavalent)
Chromium (total)
Copper
Lead
Mercury
Nickel
Selenium
Silver
Thallium
Zinc
Composition
(ppm)
Sample la Sample 2a
<0.4
28.8
-
0.37
-
1650
-
1B4
<0.2
11.8
<0.03
-
-
-
-
-
1.75
-
2625
187
365
-
17
-
-
-
3.687
Sample la
0.004
<0.002
-
<0.003
-
<0.020
-
<0.083
<0.0003
<0.006
<0.003
-
-
-
Treated sludge
TCLP
(mg/1)
Sample 2a
-
-
0.03
-
0.11
0.11
0.47
-
0.13
-
-
-
0.30
Sample 3a
-
-
0.06
-
0.09
1.17
0.41
-
0.45
-
-
-
1.45
Sample 4a
-
-
0.04
-
0.08
0.09
0.25
-
0.72
-
-
-
1.78
'Memo to Ron Turner from R.D. Gritelueschen, John Deere Company, dated January 15 1988.
-------
197*)
labl* C-3 Performance Data* for Stjhi 1 Hit Ion of FOOB Waste
ro
oo
Concentration (ppml
Const ituenl
Arsenic
Barium
Cadnlum
Chromium
Copper
le«d
Strew*
Untreated total
Untreated ICIP
1 ruled KIP*
treated KlPb
Untreated total
Untreated ICIP
Treated KIP*
treated KlPb
Untreated total
Untreated TUP
treated KIP*
treated TCIP*
Untreated totat
Untreated ICIP
treated KIP*
fretted TClPb
Untreated total
Untreated ICIP
treated KIP*
treated IClPta
Untreated total
Untreated ICIP
treated ICIP*
treated !UPb
1
Unknown
'001
<0 01
36.4
0.08
0.12
13
0 01
0.01
1270
0 34
0 51
-
40 2
0 15
0.20
35.5
0.26
0 30
-
Sanole
2 3 4
Aerospace
Aircraft manufacture
Auto part overhaul mixture of
manufacture facility F006 » F007
«0.01
-001 10 II
Small Circuit
pnqine board
HHnuf Jir.tui P manufacture Unknown MfiVnriwn
<0 01 '0 01 -0 01 0 8H
'0 01 '0 01 <0 01 -0 0?
o oi '0 oi -0 oi -o n?
?4 5 1? 6
0 07 0 04
0 30 0 04
0 19 0 14
p 04
0 01
<0 01
.-0 01
47 9 644
0.04 0 01
o 10 n 01
02 0 71
-
-------
19739
lab It C-3 (continued)
ro
vo
Concentration (pom)
Samole set «
Constituent
Mercury
Nickel
Selenlun
Silver
tine
Strew I
Unknown
Unt retted toUl
Untreated ICIP '0 Ml
treated 1UP* <0.00t
treated tUPb
Untreated total
Untreated ICIP
treated ICIP1
treated IClPb
untreated total
Untreated ICIP ratio ll 0.7.
'toll ratio If 0.5 with the enceptlon of Sai*ple Set f6 In which «l» ratio Is 1.0.
CNI> ratio Is 1.0.
^IK ration Is 15
Binder type: te»ent Kiln dust.
-------
APPENDIX D
The comparative method of measuring thermal conductivity has been
proposed as an ASTM test method under the name "Guarded, Comparative,
Longitudinal Heat Flow Technique." A thermal heat flow circuit is used
which is the analog of an electrical circuit with resistances in series.
A reference material is chosen to have a thermal conductivity close to
that estimated for the sample. Reference standards (also known as heat
meters) having the same cross-sectional dimensions as the sample are
placed above and below the sample. An upper heater, a lower heater, and
a heat sink are added to the "stack" to complete the heat flow circuit.
See Figure 1.
The temperature gradients (analogous to potential differences) along
the stack are measured with type K (chromel/alumel) thermocouples placed
at known separations. The thermocouples are placed into holes or grooves
in the references and also in the sample whenever the sample is thick
enough to accommodate them.
For molten samples, pastes, greases, and other materials that must be
contained, the material is placed into a cell consisting of a top and
bottom of Pyrex 7740 and a containment ring of marinite. The sample is 2
inch in diameter and .5 inch thick. Thermocouples are not placed into
the sample but rather the temperatures measured in the Pyrex are
extrapolated to give the temperature at the top and bottom surfaces of
the sample material. The Pyrex disks also serve as the thermal
conductivity reference material.
130
-------
GUARD
GRADIENT
STACK
GRADIENT
UPPER
GUARD
HEATER
THERMOCOUPLE
UPPER STACK
HEATER
I
TOP REFERENCE
SAMPLE
I
HEAT FLOW
TEST/SAMPLE
DIRECTION
BOTTOM
REFERENCE
SAMPLE
LOWER STACK
HEATER
I
LIQUID COOLED
HEAT SINK
I
LOWER
GUARD
HEATER
Figure C-l
SCHEMATIC DIAGRAM OF THE COMPARATIVE MSTEOD
131
-------
The stack is clamped with a reproducible load to insure intimate
contact between the components. In order to produce a linear flow of
heat down the stack and reduce the amount of heat that flows radially, a
guard tube is placed around the stack and the intervening space is filled
with insulating grains or powder. The temperature gradient in the guard
is matched to that in the stack to further reduce radial heat flow.
The comparative method is a steady state method of measuring thermal
conductivity. When equilibrium is reached the heat flux (analogous to
current flow) down the stack can be determined from the references. The
heat into the sample is given by
Q. - v (dT/dx)
in top top
and the heat out of the sample is given by
Qout - AU ^ (dT/dx)u ^
bottom 'bottom
where
A - thermal conductivity
dT/dx - temperature gradient
and top refers to the upper reference while bottom refers to the lower
reference. If the heat was confined to 'flow just down the stack, then
Q and Q would be equal. If Q. and Q . are in reasonable
in out in out
agreement, the average heat flow is calculated from
" ' "l. + "out'/2
The sample thermal conductivity is then found from
A . » Q/(dT/dx) ,
sample sample
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