x>EPA
United States
Environmental Protection
Agency
Office of
Solid Waste
Washington, D C 20460
EPA/530-SW-88-0009-6
April 1988
Solid Waste
Best
Demonstrated
Available Technology
(BOAT) Background
Document for
K062
Proposed
Volumes
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EPA/530-SW-88-0009E
Volume V
BEST DEMONSTRATED AVAILABLE TECHNOLOGY (BOAT)
BACKGROUND DOCUMENT FOR
K062
(IRON AND STEEL INDUSTRY)
U.S. Environmental Protection Agency
Office of Solid Waste
401 M Street, S.W.
Washington, D.C. 20460
James R. Berlow, Chief
Treatment Technology Section
John Keenan
Project Manager
April 1988
U.S. environmental Protection Agency
Region 5, Library (PL-12J)
77 West Jackson Boulevard, 12th Floor
Chicago, II 60604-3590
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BOAT Background Document for K062
Spent Pickle Liquor from the Steel Industry
Table of Contents
Section Page No,
EXECUTIVE SUMMARY
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 Treatabi 1 i 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
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Table of Contents (Continued)
Section Page
2. INDUSTRIES AFFECTED AND WASTE CHARACTERIZATION 46
2.1 Industries Affected and Process Description 46
2.2 Waste Characterization 48
3. APPLICABLE/DEMONSTRATED TREATMENT TECHNOLOGIES 59
3.1 Applicable Treatment Technologies 59
3.2 Demonstrated Treatment Technologies 61
3.2.1 Chromium Reduction 61
(1) Applicability and Use of This
Technology 61
(2) Underlying Principles of Operation 62
(3) Description of Chromium Reduction
Processes 63
(4) Waste Characteristics Affecting
Performance 63
(5) Design and Operating Parameters 65
3.2.2 Chemical Precipitation 67
(1) Applicability and Use of Chemical
Precipitation 67
(2) Underlying Principles of Operation 67
(3) Description of Chemical Precipitation .. 69
(4) Waste Characteristics Affecting
Performance 72
(5) Design and Operating Parameters 77
3.2.3 Sludge Filtration 79
(1) Applicability and Use of This Technology 79
(2) Underlying Principles of Operation 80
(3) Description of Sludge Filtration 80
(4) Waste Characteristics Affecting
Performance 81
(5) Design and Operating Variables That
Affect Performance 82
3.2.4 High Temperature Metals Recovery 84
(1) Applicability and Use of
This Technology 84
(2) Underlying Principles of Operation 85
(3) Description of High Temperature Metals
Recovery Processes 87
(4) Waste Characteristics Affecting
Performance 89
(5) Design and Operating Parameters 91
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Table of Contents (Continued)
Section Page
3.2.5 Stabilization 92
(1) Applicability and Use of Stabilization . 93
(2) Underlying Principles of Operation 93
(3) Description of Stabilization Processes . 95
(4) Waste Characteristics Affecting
Performance 96
(5) Design and Operating Parameters 97
3.3 Data Base 100
4. IDENTIFICATION OF BEST DEMONSTRATED AND AVAILABLE
TECHNOLOGY FOR K062 114
4.1 Introduction 114
4.1.1 Wastewaters 114
4.1.2 Nonwastewaters 115
4.2 Determination of "Available" 115
4.3 BOAT for K062 Wastes 116
5. SELECTION OF REGULATED CONSTITUENTS 117
5.1 Introduction 117
5.2 Identification of Major Constituents in K062 . 117
5.3 Selection of Regulated Constituents 118
6. CALCULATION OF BOAT TREATMENT STANDARDS 127
6.1 Correction of Analytical Data 127
6.2 Calculation of Variability Factors and
Treatment Standards 128
7. CONCLUSIONS 136
REFERENCES 141
APPENDICES
Appendix A - Analysis of Variance Test and Variability
Factor Calculation 144
Appendix B - Analytical Methods and QA/QC 158
Appendix C - Analytical Method for Determining Thermal
Conductivity of a Waste 161
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List of Tables
Table Page No.
1-1 BOAT Constituent List 18
2-1 to 2-5 Census Data (1982) for Number of Facilities in
Each State and EPA Region 49
2-6 Number of Facilities in each EPA Region 54
2-7 Major Constituent Analysis-Untreated K062 Waste 56
2-8 BOAT List Constituent Composition 56
3-1 to 3-11 Summary of Treatment Performance Data for K062
-EPA Collected Data 103
5-1 BOAT Constituents List 120
6-1 Calculation of Corrected Values for Regulated Constituents
- for Treated Wastewaters 130
6-2 Calculation of Corrected Values for Regulated Constituents
- for Treated Nonwastewaters 132
6-3 Calculation of Treatment Standards for the Regulated
Constituents - Treated Wastewaters 133
6-4 Calculation of Treatment Standards for the Regulated
Constituents - Treated Nonwastewaters 135
7-1 BOAT Treatment Standards for Nonwastewater K062 Wastes ... 140
7-2 BOAT Treatment Standards for Wastewater K062 Wastes 140
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List of Figures
Figure Page No.
2-1 Facilities Producing K062 Waste by EPA Region 55
2-2 Example of Continuous (Countercurrent) Pickling Process
and Generation of K062 57
2-3 Example of Batch Pickling Process and Generation of K062 .. 58
3-1 Continuous Hexavalent Chromium Reduction System 64
3-2 Continuous Chemical Precipitation 70
3-3 Circular Clarifiers 73
3-4 Inclined Plate Settler 74
3-5 Example High Temperature Metals Recovery System 88
3-6 Schematic Diagram of Treatment Process for K062 Wastes 102
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Executive Summary
BOAT Treatment Standards for K062
Pursuant to the Hazardous and Solid Waste Amendments (HSWA) enacted
on November 8, 1984, and in accordance with the procedures for
establishing treatment standards under Section 3004(m) of the Resource,
Conservation, and Recovery Act (RCRA), the Environmental Protection
Agency (EPA) is proposing treatment standards for the listed waste, K062,
based on the performance of a treatment technology train (consisting of
chromium reduction, chemical precipitation, and dewatering of the
precipitate) determined by the Agency to represent Best Demonstrated
Available Technology (BOAT). This background document provides the
detailed analyses that support this determination of Best Demonstrated
Available Technology (BOAT).
These BOAT treatment standards represent maximum acceptable
concentration levels for selected hazardous constituents in the wastes or
residuals from the treatment process. The levels are established as a
prerequisite for disposal of these wastes in units designated as land
disposal units according to 40 CFR Part 268 (Code of Federal
Regulations). Wastes that contain the regulated constituents at
concentrations which do not exceed the treatment standards are not
restricted from land disposal units. The Agency has chosen to set levels
for these wastes rather than to designate the use of a specific
technology.
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These standards will become effective as of August 8, 1988, as
described in the schedule set forth in 40 CFR 268.10.
According to 40 CFR Part 261.32 (hazardous wastes from specific
sources), waste code K062 is listed as spent pickle liquor generated by
steel finishing operations of facilities within the iron and steel
industry (SIC codes 331 and 332). Descriptions of the industry, the
specific processes generating these wastes, and the physical and chemical
waste characteristics are provided in Section 2.0 of this document. The
Agency estimates that approximately 978 facilities have the potential to
generate wastes identified as K062.
The Agency has determined that K062 represents a single treatability
group based on its physical and chemical composition. This group
consists of two subgroups - wastewaters and nonwastewaters. For the
purpose of the land disposal restrictions rule, wastewaters are defined
as wastes containing less than 1 percent (weight basis) filterable solids
and less than 1 percent (weight basis) total organic carbon (TOC).
Wastes not meeting this definition are classified as nonwastewaters.
While the Agency has not, at this time, specifically identified
additional wastes that would fall into this treatability group or
subgroup, this does not preclude the Agency from extrapolating these
standards to other wastes in the future.
K062 wastes, as generated, are spent pickling liquor having dissolved
BOAT List metals, high water content, and low organic content.
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The Agency has proposed BOAT treatment standards for the treatability
subgroups of K062 wastes identified as wastewaters and nonwastewaters. In
general, these treatment standards have been proposed for four metals
that the Agency believes are indicators of effective treatment for all of
the BOAT List hazardous constituents identified as typically present in
K062 wastes. These regulated metals are chromium, copper, lead, and
nickel. A detailed discussion of the selection of constituents to be
regulated is presented in Section 5 of this document.
BOAT treatment standards for wastewater and nonwastewater forms of
K062 have been proposed based on the performance data using a chromium
reduction, chemical precipitation, and precipitate dewatering treatment
train. Wastewater standards are established for total concentration of
four metals: chromium, copper, lead, and nickel. Nonwastewater
standards are established for the Teachability of two metals, chromium
and lead.
The following table lists the specific BOAT treatment standards for
K062 wastes. The Agency is setting standards based on analysis of the
total composition of K062 wastewaters and analysis of leachate for K062
nonwastewaters. The leachate concentrations are obtained by the use of
the Toxicity Characteristic Leaching Procedure (TCLP). The units for
total concentration analysis are in parts per million (mg/1) on a weight
by volume basis. The units for leachate analysis are also in parts per
million (mg/1) on a weight by volume basis. Testing procedures are
specifically identified in Appendix B.
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1556g
BOAT Treatment Standards
for
Nonwastewater K062 Wastes
Regulated metal
constituents TCLP (mg/1)
Chromium (total) 0.094
Lead 0.37
BOAT Treatment Standards
for
Wastewater K062 Wastes
Regulated metal
constituents Total concentration (mg/1)
Chromium (total) 0.32
Copper 0.42
Lead 0.04
Nickel 0 44
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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 1S84 (HSWA), 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:
(a) Solvents and dioxins standards must be promulgated by
November 8, 1986;
(b) The "California List" must be promulgated by July 8, 1987;
(c) At least one-third of all listed hazardous wastes must be
promulgated by August 8, 1988 (First Third);
(d) At least two-thirds of all listed hazardous wastes must be
promulgated by June 8, 1989 (Second Third); and
(e) 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 hafagenated
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, .11, and .12.
1.2 Summary of Promulgated BDAT 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-forcing 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 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 Groups
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 FR 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 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 only available 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 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 proprietary
or patented processes available if it determines that the treatment
method can be purchased or licensed from the proprietor or is
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:
(a) Number and types of constituents treated;
(b) Performance (concentration of the constituents in the
treatment residuals); and
(c) 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: (a) identifi-
cation of facilities for site visits, (b) engineering site visit,
(c) Sampling and Analysis Plan, (d) sampling visit, and (e) 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 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 why such data were used in the preamble and
background document 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.
15
-------
(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) Qnsite 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 (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 BOAT list. The list of hazardous constituents
within the waste codes that are targeted for treatment is referred to by
the Agency as the BOAT constituent list. This list, provided as Table
1-1, is derived from the constituents presented in 40 CFR Part 261,
Appendix VII and Appendix 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 BOAT list consists of those constituents that
can be analyzed using methods published in SW-846, Third Edition.
17
-------
1521g
Table 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
Acrylonitri le
Benzene
Bromodichloromethane
Bromomethane
n-Butyl alcohol
Carbon tetrachloride
Carbon disulfide
Chlorobenzene
2-Chloro-l ,3-butadiene
Chlorodlbromomethane
Chloroethane
2-Chloroethyl vinyl ether
Chloroform
Chloromethane
3-Chloropropene
1 , 2-Dibromo-3-chloropropane
1 , 2-Dibromoethane
Dibromomethane
Trans- 1 ,4-Oichloro-2-butene
Dichlorodif luoromethane
1 , 1-Dichloroethane
1,2-Dichloroethane
1 , 1-Dichloroethy lene
Trans -1,2-Dichloroethene
1,2-Oichloropropane
Trans-l,3-Dichloropropene
cis-1 ,3-Dichloropropene
1 ,4-Dioxane
2-Ethoxyethanol
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
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
-------
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.
218.
60.
61.
62.
Parameter
Volatiles (continued)
Isobutyl alcohol
Methanol
Methyl ethyl ketone
Methyl isobutyl ketone
Methyl methacry late
Methacrylonitrile
Methylene chloride
2-Nitropropane
Pyridine
1,1,1, 2-Tetrachloroethane
1 , 1 ,2, 2-Tetrachloroethane
Tetrachloroethene
Toluene
Tnbromomethane
1,1 ,1-Trichloroethane
1 , 1 ,2-Trichloroethane
Tnchloroethene
Trichloromonof luoromethane
1 , 2 , 3-Trlch loropropane
l,l,2-Trichloro-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 lam inof luorene
4-Aminobiphenyl
An i 1 me
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
19
-------
1521g
Table 1-1 (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
88.
89.
90.
91.
92.
93.
94.
95.
96.
97.
98.
99.
100.
101.
Parameter
Semwolatiles (continued)
Benzo(b)f luoranthene
Benzo(ghi)perylene
Benzo(k)f luoranthene
p-Benzoquinone
B i s ( 2-ch loroethoxy (methane
Bis(2-chloroethyl)ether
Bis(2-chloroisopropy 1 )ether
Bis(2-ethylhexyl)phthalate
4-Bromophenyl phenyl ether
Butyl benzyl phthalate
2-sec-Butyl-4,6-dinitrophenol
p-Chloroani 1 ine
Chlorobenzi late
p-Chloro-m-cresol
2-Chloronaphthalene
2-Chlorophenol
3-Chloropropionitri le
Chrysene
ortho-Cresol
para-Cresol
Cyclohexanone
0 1 benz ( a , h ) anthracene
Dibenzo(a,e)pyrene
Dibenzo(a, i)pyrene
m-Dichlorobenzene
o-Oichlorobenzene
p-Oichlorobenzene
3,3 '-Dichlorobenzidine
2,4-Oichlorophenol
2,6-Dichlorophenol
Diethyl phthalate
3,3'-Dimethoxybenzidine
p-Dimethylaminoazobenzene
3 ,3 '-Dimethylbenzidine
2 ,4-Dimethylphenol
Dimethyl phthalate
Di-n-butyl phthalate
1 ,4-Dinitrobenzene
4,6-Dinitro-o-cresol
2,4-Dinitrophenol
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
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
20
-------
1521g
Table 1-1 (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
Semivolati les (continued)
2,4-Dinitrotol uene
2, 6-Dinitrotoluene
Di-n-octyl phthalate
Di-n-propy Initrosamine
Diphenylamine
D i pheny 1 n i t rosami ne
1,2-Oiphenylhydrazine
Fluoranthene
Fluorene
Hexach lorobenzene
Hexachlorobutadiene
Hexachlorocyc lopentadlene
Hexach loroethane
Hexach lorophene
Hexach loropropene
Indeno( 1 ,2,3-cd)pyrene
Isosafrole
Methapyri lene
3-Methy Icho lanthrene
4,4'-Methylenebis
(2-chloroani line)
Methyl methanesulfonate
Naphthalene
1,4-Naphthoquinone
1-Naphthylamine
2-Naphthylamine
p-Nitroani line
Nitrobenzene
4-Nitrophenol
N-Nitrosodi-n-butylamine
N-Nitrosodiethylamme
N-Nitrosodimethylamine
N-Nitrosomethylethylamine
N-Nitrosomorphol me
N-Nitrosopipendine
n-Nitrosopyrrol idme
5-Nitro-o-toluidine
Pentach lorobenzene
Pentach loroethane
Pentach loron i trobenzene
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
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.
169
170.
171.
Parameter
Semwolati 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-Tet rach loropheno 1
1,2,4-Trich lorobenzene
2, 4, 5-Trich loropheno 1
2, 4, 6-Tnch loropheno 1
Tris(2,3-dibromopropyl)
phosphate
Metals
Antimony
Arsenic
Barium
Beryllium
Cadmium
Chromium (total)
Chromium (hexavalent)
Copper
Lead
Mercury
Nickel
Selenium
Silver
Thai 1 lum
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
8496-25-8
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
Orqanochlonne pesticides
Aldr in
alpha-BHC
beta-BHC
delta-BHC
gamma-BHC
Chlordane
ODD
DDE
DOT
Dieldrin
Endosulfan I
Endosulfan II
Endrin
Endrin aldehyde
Heptachlor
Heptachlor epoxide
Isodrin
Kepone
Methoxyclor
Toxaphene
Phenoxyacetic acid herbicides
2,4-Oichlorophenoxyacetic acid
Si Ivex
2.4,5-T
Orqanoohosphorous insecticides
Oisulfoton
Famphur
Methyl parathion
Parathion
Phorate
PCBjs
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
12674-11-2
11104-28-2
11141-16-5
23
-------
1521g
Table 1-1 (continued)
BOAT
reference Parameter CAS no.
rio
PCBs (continued)
203. 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 Tetrachlorodlbenzofurans
213. 2,3,7,8-Tetrachlorodibenzo-p-dioxin 1746-01-6
24
-------
The initial BOAT constituent list was published in EPA's Generic
Quality Assurance Project Plan, March 1987 (EPA/530-SW-87-011).
Additional constituents will be added to the BOAT constituent list as
additional 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, eighteen additional
constituents (hexavalent chromium, xylene (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
growing list that does not preclude the addition of new constituents when
analytical methods are developed.
25
-------
There are five major reasons why constituents were not included on
the BOAT constituent list:
(a) 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.
(b) 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.
(c) 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
constituents list.
(d) 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 chromotography (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
unkown constituents.
(e) 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
Semivolatile organics
Metals
Other inorganics
Organochlorine pesticides
Phenoxyacetic acid herbicides
Organophosphorous insecticides
PCBs
Dioxins and furans.
The constituents were placed in these categories based on their chemical
properties. The constituents in each group are expected to behave
similarily 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
technologies) because of the extreme unlikelihood of the constituent
being present.
27
-------
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
rationale for selection of regulated constituents for this waste code is
presented in Section 5 of this background document.
28
-------
(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 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 percent!le 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 only requires 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
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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) uses 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:
(a) 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.)
(b) 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.
(c) 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 of 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 are 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.
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/aualitv 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-87-001, 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:
(a) 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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(b) 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 (a) above.
(c) 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
spiked 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.
(d) 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 (a),
(b), and (c) 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
-------
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 treatment -- a 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:
(a) 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.
(b) 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.
(c) 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
-------
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
addressing 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. These residues consequently 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 valid technically in cases where the untested wastes
are generated from similar industries, 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 the case where only the industry is similar, EPA more closely examines
the waste characteristics prior to concluding that 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 the background document for each waste.
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 BOAT program and the methodology
used by the Agency to develop treatment standards. The purpose of this
section is to describe the industries affected by the land disposal
restrictions for K062 wastes, the processes generating the wastes, and
the available waste characterization data for K062 wastes.
According to 40 CFR Part 261.32 (hazardous wastes from specific
sources), the waste identified as K062 is spent pickle liquor generated
by steel finishing operations of facilities within the iron and steel
industry (SIC codes 331 and 332).
2.1 Industries Affected and Process Description
The listed waste K062 is generated by the steel industry from steel
finishing operations. The Agency estimates that approximately
978 facilities have steel finishing operations that could generate the
K062 waste. Tables 2-1 to 2-6 and Figure 2-1 present the location of
these facilities by State and EPA region. The facilities that may
generate spent pickle liquor (K062) from steel finishing operations are
those that fall under the SIC codes 331 and 332.
In the steel industry, steel products are exposed to the atmosphere
during forming and finishing operations, causing oxide scale to form on
their surfaces. This scale must be removed prior to additional
processing in order to prepare the surface for protective coatings and
cold rolling. Acid pickling is the method used most widely by the steel
industry to remove the oxide scale. In addition, the steel surface must
46
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be cleaned (by pickling) at various stages throughout the steel
production process to ensure that oxides forming on the surface are not
worked into the finished product.
The pickling operation involves the immersion of the oxidized steel
product into a heated solution of concentrated acid or acids (the
pickling agent). There are generally three types of pickling agents:
(1) sulfuric acid, (2) hydrochloric acid, and (3) combined acids. The
type of pickling agent used in a finishing operation depends on the type
of steel being processed and the surface quality desired. When a certain
concentration of metal ions builds up in the pickling bath, the solution
is considered spent and must be replaced. This spent pickle liquor is
the listed waste K062.
Pickling is accomplished in either continuous (Figure 2-2) or batch
operations (Figure 2-3):
• Continuous pickling. Continuous pickling is the method
predominantly used for pickling steel products. As shown in
Figure 2-2, steel products are continuously fed through a series
of pickling tanks containing acid solution. The pickling solution
flows in one direction, while the steel product travels in the
opposite direction, i.e., countercurrent. A fresh acid solution
is added to the last tank in a series of tanks and flows through
the tanks to an overflow located in the first tank. The acid
overflow from the first tank is the waste stream K062.
• Batch pickling. Batch operations typically utilize large, open
tanks, holding the pickling agent. As shown in Figure 2-3, steel
products are dipped in the pickling tank for the removal of
scale. After continual use, the free acid content of the pickling
tank decreases and the metal ion concentration increases. When
the free acid level falls to a specified value or the metal ion
concentration reaches a specified value, the pickling agent is
considered spent and is dumped as a batch. This spent batch of
pickling solution is K062 waste.
47
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2.2 Waste Characterization
This section includes all of the waste characterization data
available to the Agency for K062 wastes. Table 2-7 provides an estimate
of the major constituents present in the waste, along with their
approximate concentrations. The percent concentration of each major
constituent in the waste was determined using engineering judgment based
on chemical analyses. The Agency has obtained waste composition data
from its own testing program and from numerous industry sources. BOAT
list constituents had a concentration of approximately 1 percent, while
water and other inorganics had concentrations of approximately 93 and
6 percent, respectively. The ranges of BOAT List constituents in the
untreated waste are presented in Table 2-8. The constituents detected in
the untreated K062 waste are BOAT list metals, namely, arsenic, chromium,
copper, lead, nickel, and zinc. Chromium, copper, and nickel appear in
the highest concentrations in the K062 waste tested by the Agency. The
Agency has data showing that lead may also be present in K062 wastes
generated from pickling operations involving leaded steels. No organics
were analyzed for in the untreated and treated K062 waste; however, the
Agency does not believe that they will be present in treatable
concentrations in the untreated K062 wastes.
48
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1008g
Table 2-1 Census Data (1982) for Number of Facilities
in Each State and EPA Region
Blast Furnaces and Steel Mills3
State
AL (IV)
AK (X)
AZ (IX)
AR (VI)
CA (IX)
CO (VIII)
CT (1)
DE (III)
DC (III)
FL (IV)
GA (IV)
HI (IX)
ID (X)
IL (V)
IN (V)
IA (VII)
KS (VII)
KY (IV)
LA (VI)
ME (I)
MD (III)
MA (I)
MI (V)
MN (V)
MS (IV)
MO (VIII)
Faci lities
15
1
19
2
1
1
5
4
19
11
1
8
5
3
15
3
2
4
State
MT
NE
NV
NH
NJ
NM
NY
NC
NO
OH
OK
OR
PA
RI
SC
SD
TN
TX
LIT
VT
VA
WA
UV
WI
WY
(VIII)
(VII)
(IX)
(I)
(ID
(VI)
(ID
(IV)
(VIII)
(V)
(VI)
(X)
(III)
(I)
(IV)
(VIII)
(IV)
(VI)
(VIII)
(I)
(HI)
(X)
(III)
(V)
(VIII)
Facilities EPA Region
I
1 II
III
IV
6 V
VI
20 VII
3 VIII
IX
26 X
5
5
52
5
7
14
2
7
5
4
4
Totals
1
26
67
49
78
24
2
8
20
10
285
alncludes data for SIC code 3312 only.
Source: 1982 Census of Manufacturers.
49
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1008g
Table 2-2 Census Data (1982) for Number of Facilities
in Each State and EPA Region
Electrometallurgical Products3
State Facilities State Facilities
AL (IV)
AK (X)
AZ (IX)
AR (VI)
CA (IX)
CO (VIII)
CT (I)
DE (III)
DC (III)
FL (IV)
GA (IV)
HI (IX)
ID (X)
IL (V)
IN (V)
IA (VII)
KS (VII)
KY (IV)
LA (VI)
ME (I)
MO (III)
MA (I)
MI (V)
MN (V)
MS (IV)
MO (VIII)
MT (VIII)
NE (VII)
NV (IX)
NH (I)
NJ (II) 3
NM (VI)
NY (II)
NC (IV)
ND (VIII)
OH (V) 8
OK (VI)
OR (X) 2
PA (III) 1
RI (I)
SC (IV) 2
1 SO (VIII)
TN (IV) 4
1 TX (VI)
UT (VIII)
VT (I)
VA (III)
WA (X)
WV (III) 4
WI (V)
WY (VIII)
EPA Region Totals
I
II 3
III 5
IV 7
V 8
VI
VII 1
VIII
IX
X _2
26
Includes data for SIC code 3313 only.
Source 1982 Census of Manufacturers.
50
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1003g
Table 2-3 Census Data (1982) for Number of Facilities
in Each State and EPA Region
Steel Wire and Related Products3
State
AL (IV)
AK (X)
AZ (IX)
AR (VI)
CA (IX)
CO (VIII)
CT (I)
DE (III)
DC (III)
FL (IV)
GA (IV)
HI (IX)
ID (X)
IL (V)
IN (V)
IA (VII)
KS (VII)
KY (IV)
LA (VI)
ME (I)
MD (III)
MA (I)
MI (V)
MN (V)
MS (IV)
MO (VIII)
Faci 1 it IBS
6
2
34
15
2
13
6
30
10
4
3
4
19
12
2
4
7
State Facilities
MT
NE
NV
NH
NJ
NM
NY
NC
NO
OH
OK
OR
PA
RI
SC
SO
TN
TX
UT
VT
VA
WA
WV
WI
WY
(VIII)
(VII)
(IX)
(I)
(II) 16
(VI)
(ID 15
(IV) 5
(VIII)
(V) 21
(VI) 3
(X)
(III) 25
(I)
(IV) 6
(VIII)
(IV) 5
(VI) 22
(VIII)
(I)
(III) 2
(X)
(III)
(V) 4
(VIII)
EPA Region Totals
I 34
II 31
III 33
IV 49
V 79
VI 30
VII
VIII 7
IX 34
X
297
alncludes data for SIC code 3315 only.
Source: 1982 Census of Manufacturers.
51
-------
lOOHg
Table 2-4 Census Data (1982) for Number of Facilities
in Each State and EPA Region
Cold Finishing of Steel Shapes
State Facilities
AL (IV)
AK (X)
AZ (IX)
AR (VI)
CA (IX) 12
CO (VIII) 10
CT (I)
DE (III)
DC (III)
FL (IV)
GA (IV)
HI (IX)
ID (X)
IL (V) 18
IN (V) 7
IA (VII)
KS (VII)
KY (IV)
LA (VI)
ME (I)
MD (III) 2
MA (I) 4
MI (V) 22
MN (V)
MS (IV) 6
MO (VIII)
State Facilities
MT (VIII)
NE (VII)
NV (IX)
NH (I)
NJ (II) 9
NM (VI)
NY (II) 8
NC (IV)
ND (VIII)
OH (V) 24
OK (VI)
OR (X)
PA (III) 23
RI (I)
SC (IV)
SO (VIII)
TN (IV)
TX (VI) 10
UT (VIII)
VT (I)
VA (III)
WA (X)
WV (III)
WI (V) 5
WY (VIII)
EPA Region Totals
I 4
II 17
III 25
IV 6
V 76
VI 10
VII
VIII 10
IX 12
X
160
alncludes data for SIC code 3316 only.
Source- 1982 Census of Manufacturers.
52
-------
1008g
Table 2-5 Census Data (1982) for Number of Facilities
in Each State and EPA Region
Steel Pi le and Tubes3
State
AL (IV)
AK (X)
AZ (IX)
AR (VI)
CA (IX)
CO (VIII)
CT (I)
DE (III)
DC (III)
Ft (IV)
GA (IV)
HI (IX)
ID (X)
IL (V)
IN (V)
IA (VII)
KS (VII)
KY (IV)
LA (VI)
ME (I)
MO (III)
MA (I)
MI (V)
MN (V)
MS (IV)
MO (VIII)
Faci 1 ities
2
2
26
3
3
19
13
1
3
3
2
25
3
4
State Facilities
MT (VIII)
NE (VII)
NV (IX)
NH (I)
NJ (II) 8
NM (VI)
NY (II) 7
NC (IV)
NO (VIII)
OH (V) 26
OK (VI) 5
OR (X)
PA (III) 27
RI (I)
SC (IV)
SD (VIII)
TN (IV) 6
TX (VI) 12
UT (VIII)
VT (I)
VA (III)
WA (X) 1
WV (III) 2
WI (V) 7
WY (VIII)
EPA Region Totals
I
II 15
III 31
IV 14
V 93
VI 22
VII 1
VIII 7
IX 26
X 1
210
Includes data for SIC code 3317 only.
Source: 1982 Census of Manufacturers.
53
-------
1008g
Table 2-6 Number of Facilities in Each EPA Region
EPA Region Totals
I 39
II 92
III 161
IV 125
V 334
VI 86
VII 4
VIII 32
IX 92
X 13
978
54
-------
en
en
MA
FIGURE 2-1 FACILITIES PRODUCING K062 WASTE BY EPA REGION
-------
1008g
Table 2-7 Major Constituent Analysis
Untreated K062 Waste
Constituent Concentration %
BOAT List Constituents
(primarily chromium, copper, and
nickel)
Water
Other Inorganics
Total
93
6
100%
Source: U.S. Environmental Protection Agency. 1986. Onsite Engineering Report
of Treatment Technology Performance and Operation for Envirite
Corporation.
Table 2-8 BOAT List Constituent Composition
BOAT metals Untreated waste concentration, ppm
(a) (b)
Arsenic
Barium
Cadmium
Chromium (hexavalent)
Chromium (total)
Copper
Lead
Nickel
Zinc
<0.1 to 3
<10
<5
0.079 to 1
6 to 7000
5 to 865
<10
4 to 100,310
<0.4 to 9
-
-
-
0.005
2 to
-
0.12
-
-
to 19
12,400
to 1550
Source:
(a) U.S. Environmental Protection Agency. 1986. Onsite Engineering Report of
Treatment Technology Performance and Operation for Envirite Corporation,
Tables 6-1 to 6-12.
(b) U.S. Environmental Protection Agency - Characterization of Waste
Streams Listed in 40 CFR 261 Waste Profiles, pp. 299 and 300.
56
-------
STEEL PRODUCT
\-
(®) *"
•'
®v /®~
xa er
TANK NO. 1
*\ /*
\3 f/
TANK NO. i
~©y /€T
NO &
TANK NO. 1
^
*J
\
FRESH ACID
f
r
)
* i
uC (CONSTANT
> FEED RATE)
r WATER
(CONSTANT
FEED RATE)
-Q>- JS.
\^ dt
TANK NO. 4
*•
PICKLING TANKS
Ln CONSTANT OVERFLOW
(CASCADE)
^ OF SPENT PICKLE LIQUOR - KO62
ACID
1
fwATE*
"®yAA^€T
*\B/i
L
WATER SUPPLY
fwATER
a ^» ». *
\a_e/
RINSE
WATER DISCHARGE
FIGURE 2-2 EXAMPLE OF CONTINUOUS (COUNTERCURRENT) PICKLING PROCESS
AND GENERATION OF KO62
REFERENCE: U.S. ENVIRONMENTAL PROTECTION AGENCY 1982.
-------
VVVVNXNX
en
Co
PERIODIC
OVERFLOW
DISCHARGE
-SPENT ACID (DUMP)
DISCHARGE
SPENT PICKLE LIQUOR
K062
WATER
(MAKEUP)
STEEL
PRODUCT
WATER SUPPLY
WATER
* (CONTINUOUS FLOW)
DIP RINSE TANK
-ACID RINSE WATER
CONTINUOUS DISCHARGE
FIGURE 2-3 EXAMPLE OF BATCH PICKLING PROCESS AND GENERATION OF KO62
REFERENCE: U.S. ENVIRONMENTAL PROTECTION AGENCY 1082.
-------
3. APPLICABLE/DEMONSTRATED TREATMENT TECHNOLOGIES
The previous section discussed the industries generating K062 and the
composition of the untreated waste. This section describes the
applicable treatment technologies and presents performance data for the
treatment of K062 waste. The Agency identified the applicable treatment
technologies based on the waste composition. The technologies considered
to be applicable are those that treat BOAT list metals by reducing their
concentration and/or their Teachability. Included in this section are
discussions of those treatment technologies that have been demonstrated
on a commercial basis. The treatment technology tested by the Agency,
along with its associated performance data, is presented in the following
sections. A schematic diagram of the treatment system for K062 tested by
the Agency (chromium reduction and chemical precipitation, followed by
dewatering of the precipitate) is shown in Figure 3-6.
3.1 Applicable Treatment Technologies
The methodology used to determine the applicable technologies is
called analysis of parameters affecting treatment selection (PATS). This
methodology involves the identification of applicable treatment
technologies based on the composition of the waste. A description of the
PATS methodology and a discussion of the parameters are provided in
Volume I, Background Document for BOAT Treatment Technologies. As shown
in Section 2, the tested waste primarily contains BOAT list metals,
water, and other inorganic constituents. Some of the BOAT list metals
reported in the untreated K062 are arsenic, chromium (hexavalent),
59
-------
chromium (total), copper, lead, nickel, and zinc. Other waste
characteristics that may affect treatment selection for K062 are
filterable solids and oil and grease content. Filterable solids are
0.01 percent (100 mg/1) or less; oil and grease content is less than
10 mg/1.
The Agency has identified treatment technologies that may be
applicable to K062 because they are designed to reduce the concentration
of BOAT list metals present in the treated residual and/or reduce the
leachability of BOAT list metals in the treated residual. The selection
of the treatment technologies applicable for treating BOAT list metals in
K062 is based on current literature sources and field testing. K062
wastes tested by EPA contain dissolved BOAT list metals (approximately
1 percent), low oil and grease content (<0.2 to 6 mg/1), and low
filterable solids (<1 to 100 mg/1). Hence, chemical precipitation
followed by dewatering of the precipitated solids is an applicable
technology for the removal of the dissolved metals from K062. Applicable
treatment for the solids precipitated includes stabilization or metals
recovery. Additionally, the presence of hexavalent chromium indicates
the need for chromium reduction to convert hexavalent chromium to
trivalent chromium prior to precipitation. Dewatering of the
precipitated solids results in a nonwastewater stream called filter cake
and a wastewater stream called filtrate. The filtrate may be further
processed by polishing filtration, such as multimedia filtration, to
remove the remaining suspended solids. Stabilization of the filter cake
60
-------
may be used to reduce the Teachability of the BOAT list metals. Metals
recovery from the filter cake may be used to reduce the total
concentration of the metals in the filter cake.
3.2 Demonstrated Treatment Technologies
All of the applicable technologies are demonstrated. Hexavalent
chromium reduction, chemical precipitation, and dewatering by settling
and/or filtration are widely practiced as a metals treatment technology.
In addition, polishing filtration is a well-documented technology. The
use of dewatering by vacuum filtration only, as a substitute for
settling, is a less commonly practiced technology, but was used on a
full-scale basis at a facility tested by EPA. Regarding treatment of
precipitated solids, stabilization is well demonstrated on K062 wastes.
EPA also has information showing that high temperature metals recovery is
a demonstrated technology for K062 wastes. Of the demonstrated treatment
technologies, chromium reduction, chemical precipitation, sludge
filtration, stabilization, and high temperature metals recovery are
discussed below.
3.2.1 Chromium Reduction
(1) Applicability and use of this technology. The process of
6+
hexavalent chromium (Cr ) reduction involves conversion from the
hexavalent form to the trivalent form of chromium. This technology has
wide application to hexavalent chromium wastes, including plating
solutions, stainless steel acid baths and rinses, "chrome conversion"
61
-------
coating process rinses, and chromium pigment manufacturing wastes.
Because this technology requires the pH to be in the acidic range, it
would not be applicable to a waste that contains significant amounts of
cyanide or sulfide. In such cases, lowering of the pH can generate toxic
gases such as hydrogen cyanide or hydrogen sulfide. It is important to
note that additional treatment is required to remove trivalent chromium
from solution.
(2) Underlying principles of operation. The basic principle of
treatment is to reduce the valence of chromium in solution (in the form
of chromate or dichromate ions) from the valence state of six (+6) to the
trivalent (+3) state. "Reducing agents" used to effect the reduction
include sodium bisulfite, sodium metabisulfite, sulfur dioxide, sodium
hydrosulfide, or the ferrous form of iron.
A typical reduction equation, using sodium sulfite as the reducing
agent, is:
H2Cr20? + 3Na2S03 + (SO^ -» Cr^SO^ + SNa^ + 4^0.
The reaction is usually accomplished at pH values in the range of 2 to 3.
At the completion of the chromium reduction step, the trivalent
chromium compounds are precipitated from solution by raising the pH to a
value exceeding about 8. The less soluble trivalent chromium (in the
form of chromium hydroxide) is then allowed to settle from solution. The
precipitation reaction is as follows:
Cr (SO ) + 3Ca(OH) - 2Cr(OH) + CaSO .
62
-------
(3) Description of chromium reduction process. The chromium
reduction treatment process can be operated in a batch or a continuous
mode. A batch system will consist of a reaction tank, a mixer to
homogenize the contents of the tank, a supply of reducing agent, and a
source of acid and base for pH control.
A continuous chromium reduction treatment system, as shown in
Figure 3-1, will usually include a holding tank upstream of the reaction
tank for flow and concentration equalization. It will also include
instrumentation to automatically control the amount of reducing agent
added and the pH of the reaction tank. The amount of reducing agent is
controlled by the use of a sensor called an oxidation reduction potential
(ORP) cell. The ORP sensor electronically measures, in millivolts, the
level to which the redox reaction has proceeded at any given time. It
must be noted, though, that the ORP reading is very pH dependent.
Consequently, if the pH is not maintained at a steady value, the ORP will
vary somewhat, regardless of the level of chromate reduction.
(4) Waste characteristics affecting performance. In determining
whether chromium reduction can treat an untested waste to the same level
of performance as a previously tested waste, EPA will examine waste
characteristics that affect the reaction involved with either lowering
the pH or reducing the hexavalent chromium. EPA believes that such
characteristics include the oil and grease content of the waste, total
dissolved solids, and the presence of other compounds that would undergo
reduction reaction.
63
-------
REDUCING
AGENT
FEED
SYSTEM
ACID
FEED
SYSTEM
HEXAVALENT-
CHROMIUM
CONTAINING
WASTEWATER
"(8^
ALKALI
FEED
SYSTEM
r
DD
ORP pH
SENSORS
TO SETTLING
REDUCTION
PRECIPITATION
ELECTRICAL CONTROLS
o
MIXER
FIGURE 3-1
CONTINUOUS HEXAVALENT
CHROMIUM REDUCTION SYSTEM
-------
(a) Oil and grease. EPA believes that these compounds could
potentially interfere with the oxidation-reduction reactions, as well as
cause monitoring problems by fouling the instrumentation (e.g.,
electrodes). Oil and grease concentrations can be measured by EPA
Methods 9070 and 9071.
(b) Total dissolved solids. These compounds can interfere with the
addition of treatment chemicals into solution and possibly cause
monitoring problems.
(c) Other reducible compounds. These compounds would generally
consist of other metals in the waste. Accordingly EPA will evaluate the
type and concentration of other metals in the waste in evaluating
transfer of treatment performances.
(5) Design and operating parameters. The parameters that EPA will
examine in assessing the design and operation of a chromium reduction
treatment system are discussed below.
(a) Treated and untreated design concentration. EPA will need to
know the level of performance that the facility is designed to achieve in
order to ensure that the design is consistent with best demonstrated
practices. This parameter is important in that a system will not usually
perform better than the design. In addition to awareness of the treated
design concentration, it is also important to know the characteristics of
the untreated waste that the system is designed to handle. Accordingly,
EPA will obtain data on the untreated wastes to ensure that the waste
characteristics fall within the design specifications.
65
-------
(b) Reducing agent. The choice of a reducing agent establishes the
chemical reaction upon which the chromium reduction system is based. The
amount of reducing agent must be monitored and controlled in both batch
and continuous systems. In batch systems, the reducing agent is usually
controlled by an analysis of the hexavalent chromium remaining in the
solution. For continuous systems, the ORP reading is used to monitor and
control the addition of a reducing agent.
The reading ORP will change slowly until the correct amount of
reducing agent has been added, at which point the reading will change
more rapidly, indicating that the reaction has been completed. The
setpoint for the ORP monitor is approximately the reading just after the
rapid change has begun. The reduction system must then be monitored
periodically to determine whether the selected setpoint needs further
adjustment.
(c) £H. For both batch and continuous systems, pH is an important
parameter because of its effect on the reduction reaction. While it can
be monitored intermittently during treatment for a batch system, the pH
should be continuously monitored for continuous systems because of its
effect on the ORP. In evaluating the design and operation of a <
continuous chromium reduction system, it is important to know the pH on
which the design ORP value is based, as well as the designed ORP value.
(d) Retention time. Retention time should be adequate to ensure
that the hexavalent chromium reduction reaction goes to completion. In
the case of the batch reactor, the retention time is varied by adjusting
66
-------
the treatment time in the reaction tank. If the process is continuous,
it is important to monitor the feed rate to ensure that the designed
residence time is achieved.
The chromium reduction process which provides data for treating K062
used iron-bearing (ferrous) acid wastes to reduce hexavalent chromium to
trivalent chromium in a single stage batch reaction. Each treatment tank
used a mechanical mixing system. According to plant personnel, the
weight ratio of ferrous iron to hexavalent chromium required for complete
reduction is 3.2 to 1.0. Some industrial treatment facilities, however,
often use other amounts of iron to ensure complete reduction of the
hexavalent chromium. Completion of the chromium reduction step was
checked by measuring the hexavalent chromium concentration until it was
no longer detected in the treatment tank.
3.2.2 Chemical Precipitation
(1) Applicability and use of this technology. Chemical
precipitation is used when dissolved metals are to be removed from
solution. This technology can be applied to a wide range of wastewaters
containing dissolved BOAT list metals and other metals as well. This
treatment process has been practiced widely by industrial facilities
since the 1940s.
(2) Underlying principles of operation. The underlying principle of
chemical precipitation is that metals in wastewater are removed by the
addition of a treatment chemical that converts the dissolved metal to a
67
-------
metal precipitate. This precipitate is less soluble than the original
metal compound and therefore settles out of solution, leaving a lower
concentration of the metal present in the solution. The primary
chemicals used to convert soluble metal compounds to less soluble forms
include: lime (Ca(OH) ), caustic (NaOH), sodium sulfide (Na S), and,
to a lesser extent, soda ash (Na CO ), phosphate, and ferrous sulfide
£ 0
(FeS).
The solubility of a particular compound will depend on the extent to
which the electrostatic forces holding the ions of the compound together
can be overcome. The solubility will change significantly with
temperature; most metal compounds are more soluble as the temperature
increases. Additionally, the solubility will be affected by the other
constituents present in a waste. As a general rule, nitrates, chlorides,
and sulfates are more soluble than hydroxides, sulfides, carbonates, and
phosphates.
An important concept related to treatment of the soluble metal
compounds is pH. This term provides a measure of the extent to which a
solution contains either an excess of hydrogen or hydroxide ions. The pH
scale ranges from 0 to 14, with 0 being the most acidic, 14 representing
the highest alkalinity or hydroxide ion (OH ) content, and 7.0 being
neutral.
When hydroxide is used, as is often the case, to precipitate the
soluble metal compounds, the pH is frequently monitored to ensure that
68
-------
sufficient treatment chemicals are added. It is important to point out
that pH is not a good measure of treatment chemical addition for
compounds other than hydroxides. When sulfide is used, for example,
facilities might use an oxidation-reduction potential meter (ORP)
correlation to ensure that sufficient treatment chemical is used.
Following conversion of the relatively soluble metal compounds to
metal precipitates, the effectiveness of chemical precipitation is a
function of the physical removal, which usually relies on a settling
process. A particle of a specific size, shape, and composition will
settle at a specific velocity, as described by Stokes' Law. For a batch
system, Stokes' law is a good predictor of settling time because the
pertinent particle parameters remain essentially constant. Nevertheless,
in practice, settling time for a batch system is normally determined by
empirical testing. For a continuous system, the theory of settling is
complicated by factors such as turbulence, short-circuiting, and velocity
gradients, increasing the importance of the empirical tests.
(3) Description of chemical precipitation. The equipment and
instrumentation required for chemical precipitation vary depending on
whether the system is batch or continuous. Both operations are discussed
below; a schematic of the continuous system is shown in Figure 3-2.
For a batch system, chemical precipitation requires only a feed
system for the treatment chemicals and a second tank where the waste can
be treated and allowed to settle. When lime is used, it is generally
69
-------
TREATMENT
CHEMICAL
FEED
SYSTEM
COAGULANT OR
FLOCCULANT FEED SYSTEM
WASTEWATER
FEED
EFFLUENT TO
DISCHARGE OR
SUBSEQUENT
TREATMENT
ELECTRICAL CONTROLS
WASTEWATER FLOW
MIXER
.SLUDGE TO
DEWATERING
FIGURE 3-2 CONTINUOUS CHEMICAL PRECIPITATION
-------
added to the reaction tank in a slurry form. In a batch system, the
supernate is usually analyzed before discharge, thus minimizing the need
for instrumentation.
In a continuous system, additional tanks and instrumentation are
necessary to ensure that the system is operating properly. In this
system, the first tank that the wastewater enters is referred to as an
equalization tank. This is where the waste can be mixed in order to
provide more uniformity, minimizing wide swings in the type and
concentration of constituents being sent to the reaction tank. It is
important to reduce the variability of the waste sent to the reaction
tank because control systems inherently are limited with regard to the
maximum fluctuations that can be managed.
Following equalization, the waste is pumped to a reaction tank where
treatment chemicals are added; this is done automatically by using
instrumentation that senses the pH of the system and then pneumatically
adjusts the position of the treatment chemical feed valve such that the
design pH value is achieved. Both the complexity and the effectiveness
of the automatic control system will vary depending on the variation in
the waste and the pH range that is needed to properly treat the waste.
An important aspect of the reaction tank design is that it be
well-mixed so that the waste and the treatment chemicals are both
dispersed throughout the tank, in order to ensure comingling of the
reactant and the treatment chemicals. In addition, effective dispersion
71
-------
of the treatment chemicals throughout the tank is necessary to properly
monitor and thereby control the amount of treatment chemicals added.
After the waste is reacted with the treatment chemical, it flows to a
quiescent tank where the precipitate is allowed to settle and
subsequently be removed. Settling can be chemically assisted through the
use of flocculating compounds. Flocculants increase the particicle size
and density of the precipitated solids, both of which increase the rate
of settling. The particular flocculating agent that will best improve
settling characteristics will vary depending on the particular waste;
selection of the flocculating agent is generally accomplished by
performing laboratory bench tests. Settling can be conducted in a large
tank by relying solely on gravity or can be mechanically assisted through
the use of a circular clarifier or an inclined separator. Schematics of
the latter two separators are shown in Figures 3-3 and 3-4.
Filtration can be used for further removal of precipitated residuals
both in cases where the settling system is underdesigned and in those in
which the particles are difficult to settle. Polishing filtration is
discussed in a separate technology section.
(4) Waste characteristics affecting performance. In determining
whether chemical precipitation is likely to achieve the same level of
performance on an untested waste as on a previously tested waste, we will
examine the following waste characteristics: (1) the concentration and
type of the metal(s) in the waste, (2) the concentration of suspended
72
-------
SLUDGE
INFLUENT
CENTER FEED CLARIFIER WITH SCRAPER SLUDGE REMOVAL SUSTEM
INFLUENT
EFFLUENT
SLUDGE
RIM FEED - CENTER TAKEOFF CLARIFIER WITH
HYDRAULIC SUCTION SLUDGE REMOVAL SYSTEM
INFLUENT
EFFLUENT
SLUDGE
RIM FEED - RIM TAKEOFF CLARIFIER
FIGURE 3-3
CIRCULAR CLARIFIERS
73
-------
INFLUENT
EFFLUENT
FIGURE 3-4
INCLINED PLATE SETTLER
74
-------
solids (TSS), (3) the concentration of dissolved solids (IDS),
(4) whether the metal exists in the wastewater as a complex, and (5) the
oil and grease content. These parameters affect the chemical reaction of
the metal compound, the solubility of the metal precipitate, or the
ability of the precipitated compound to settle.
(a) Concentration and type of metals. For most metals, there is a
specific pH at which the metal hydroxide is least soluble. As a result,
when a waste contains a mixture of many metals, it is not possible to
operate a treatment system at a single pH that is optimal for the removal
of all metals. The extent to which this affects treatment depends on the
particular metals to be removed and their concentrations. An alternative
can be to operate multiple precipitations, with intermediate settling,
when the optimum pH occurs at markedly different levels for the metals
present. The individual metals and their concentrations can be measured
using EPA Method 6010.
(b) Concentration and type of total suspended solids (TSS). Certain
suspended solid compounds are difficult to settle because of their
particle size or shape. Accordingly, EPA will evaluate this
characteristic in assessing transfer of treatment performance. Total
suspended solids can be measured by EPA Wastewater Test Method 160.2.
(c) Concentration of total dissolved solids (TDS). Available
information shows that total dissolved solids can inhibit settling. The
literature states that poor flocculation is a consequence of high TDS,
75
-------
and shows that higher concentrations of total suspended solids are found
in treated residuals. Poor flocculation can adversely affect the degree
to which precipitated particles are removed. Total dissolved solids can
be measured by EPA Wastewater Test Method 160.1.
(d) Complexed metals. Metal complexes consist of a metal ion
surrounded by a group of other inorganic or organic ions or molecules
(often called ligands). In the complexed form, the metals have a greater
solubility and therefore may not be as effectively removed from solution
by chemical precipitation. EPA does not have an analytical method to
determine the amount of complexed metals in the waste. The Agency
believes that the best measure of complexed metals is to analyze for some
common complexing compounds (or complexing agents) generally found in
wastewater for which analytical methods are available. These complexing
agents include ammonia, cyanide, and EDTA. The analytical method for
cyanide is EPA Method 9010. The method for EDTA is ASTM Method D3113.
Ammonia can be analyzed using EPA Wastewater Test Method 350.
(e) Oil and grease content. The oil and grease content of a
particular waste directly inhibits the settling of the precipitate.
Suspended oil droplets float in water and tend to suspend particles such
as chemical precipitates that would otherwise settle out of the
solution. Even with the use of coagulants or flocculants, the separation
of the precipitate is less effective. Oil and grease content can be
measured by EPA Method 9071.
76
-------
(5) Design and operating parameters. The parameters that EPA will
evaluate when determining whether a chemical precipitation system is well
designed are: (1) design value for treated metal concentrations, as well
as other characteristics of the waste used for design purposes (e.g.,
total suspended solids), (2) pH, (3) residence time, (4) choice of
treatment chemical, and (5) choice of coagulant/flocculant. Below is an
explanation of why EPA believes these parameters are important to a
design analysis; in addition, EPA explains why other design criteria are
not included in EPA's analysis.
(a) Treated and untreated design concentrations. EPA pays close
attention to the treated concentration the system is designed to achieve
when determining whether to sample a particular facility. Since the
system will seldom out-perform its design, EPA must evaluate whether the
design is consistent with best demonstrated practice.
The untreated concentrations that the system is designed to treat are
important in evaluating any treatment system. Operation of a chemical
precipitation treatment system with untreated waste concentrations in
excess of design values can easily result in poor performance.
(b) pH. The pH is important because it can indicate that sufficient
treatment chemical (e.g., lime) is added to convert the metal
constituents in the untreated waste to forms that will precipitate. The
pH also affects the solubility of metal hydroxides and sulfides, and
therefore directly impacts the effectiveness of removal. In practice,
77
-------
the design pH is determined by empirical bench testing, often referred to
as "jar" testing. The temperature at which the "jar" testing is
conducted is important in that it also affects the solubility of the
metal precipitates. Operation of a treatment system at temperatures
above the design temperature can result in poor performance. In
assessing the operation of a chemical precipitation system, EPA prefers
continuous data on the pH and periodic temperature conditions throughout
the treatment period.
(c) Residence time. The residence time is important because it
impacts the completeness of the chemical reaction to form the metal
precipitate and, to a greater extent, the amount of precipitate that
settles out of solution. In practice, it is determined by "jar"
testing. For continuous systems, EPA will monitor the feed rate to
ensure that the system is operated at design conditions. For batch
systems, EPA will want information on the design parameter used to
determine sufficient settling time (e.g., total suspended solids).
(d) Choice of treatment chemical. A choice must be made as to what
type of precipitating agent (i.e., treatment chemical) will be used. The
factor that most affects this choice is the type of metal constituents to
be treated. Other design parameters, such as pH, residence time, and
choice of coagulant/flocculant agents, are based on the selection of the
treatment chemical.
78
-------
(e) Choice of coagulant/flocculant. This parameter is important
because these compounds improve the settling rate of the precipitated
metals and allows for smaller systems (i.e., lower retention time) to
achieve the same degree of settling as a much larger system. In
practice, the choice of the best agent and the required amount is
determined by "jar" testing.
(f) Mixing. The degree of mixing is a complex assessment that
includes, among other things, the energy supplied, the time the material
is mixed, and the related turbulence effects of the specific size and
shape of the tank. EPA will, however, consider whether mixing is
provided and whether the type of mixing device is one that could be
expected to achieve uniform mixing. For example, EPA may not use data
from a chemical precipitation treatment system where an air hose was
placed in a large tank to achieve mixing.
3.2.3 Sludge Filtration
(1) Applicability and use of this technology. Sludge filtration,
also known as sludge dewatering or cake-formation filtration, is a
technology used on wastes that contain high concentrations of suspended
solids, generally higher than 1 percent. The remainder of the waste is
essentially water. Sludge filtration is applied to sludges, typically
those that have settled to the bottom of clarifiers, for dewatering.
After filtration, these sludges can be dewatered to 20 to 50 percent
solids.
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(2) Underlying principle of operation. The basic principle of
filtration is the separation of particles from a mixture of fluids and
particles by a medium that permits the flow of the fluid but retains the
particles. As would be expected, larger particles are easier to separate
from the fluid than smaller particles. Extremely small particles, in the
colloidal range, may not be filtered effectively and may appear in the
treated waste. To mitigate this problem, the wastewater should be
treated prior to filtration to modify the particle size distribution in
favor of the larger particles, by the use of appropriate precipitants,
coagulants, flocculants, and filter aids. The selection of the
appropriate precipitant or coagulant is important because it affects the
particles formed. For example, lime neutralization usually produces
larger, less gelatinous particles than does caustic soda precipitation.
For larger particles that become too small to filter effectively because
of poor resistance to shearing, shear resistance can be improved by the
use of coagulants and flocculants. Also, if pumps are used to feed the
filter, shear can be minimized by designing for a lower pump speed, or by
use of a low shear type of pump.
(3) Description of sludge filtration. For sludge filtration,
settled sludge is either pumped through a cloth-type filter media (such
as in a plate and frame filter that allows solid "cake" to build up on
the media) or the sludge is drawn by vacuum through the cloth media (such
as on a drum or vacuum filter, which also allows the solids to build).
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In both cases the solids themselves act as a filter for subsequent solids
removal. For a plate and frame type filter, removal of the solids is
accomplished by taking the unit off line, opening the filter, and
scraping the solids off. For the vacuum type filter, cake is removed
continuously. For a specific sludge, the plate and frame type filter
will usually produce a drier cake than a vacuum filter. Other types of
sludge filters, such as belt filters, are also used for effective sludge
dewatering.
(4) Waste characteristics affecting performance. The following
characteristics of the waste will affect performance of a sludge
filtration unit: (a) size of particles and (b) type of particles.
(a) Size of particles. The smaller the particle size, the more the
particles tend to go through the filter media. This is especially true
for a vacuum filter. For a pressure filter (like a plate and frame),
smaller particles may require higher pressures for equivalent throughput,
since the smaller pore spaces between particles create resistance to flow.
(b) Type of particles. Some solids formed during metal
precipitation are gelatinous in nature and cannot be dewatered well by
cake-formation filtration. In fact, for vacuum filtration a cake may not
form at all. In most cases, solids can be made less gelatinous by use of
the appropriate coagulants and coagulant dosage prior to clarification,
or after clarification but prior to filtration. In addition, the use of
lime instead of caustic soda in metal precipitation will reduce the
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formation of gelatinous solids. Also, the addition of filter aids to a
gelatinous sludge, such as lime or diatomaceous earth, will help
significantly. Finally, precoating the filter with diatomaceous earth
prior to sludge filtration will assist in dewatering gelatinous sludges.
(5) Design and operating variables that affect performance. For
sludge filtration, the following design and operating variables affect
performance:
• Type of filter selected;
• Size of filter selected;
• Feed pressure; and
• Use of coagulants or filter aids.
(a) Type of filter. Typically, pressure type filters (such as a
plate and frame) will yield a drier cake than a vacuum type filter and
will also be more tolerant of variations in influent sludge
characteristics. Pressure type filters, however, are batch operations,
so that when cake is built up to the maximum depth physically possible
(constrained by filter geometry), or to the maximum design pressure, the
filter is turned off while the cake is removed. A vacuum filter is a
continuous device (i.e., cake discharges continuously), but will usually
be much larger than a pressure filter with the same capacity. A hybrid
device is a belt filter, which mechanically squeezes sludge between two
continuous fabric belts.
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(b) Size of filter. As with in-depth filters, the larger the filter,
the greater its hydraulic capacity and the longer the filter runs between
cake discharge.
(c) Feed pressure. This parameter impacts both the design pore size
of the filter and the design flow rate. It is important that in treating
waste the design feed pressure not be exceeded; otherwise, particles may
be forced through the filter medium, resulting in ineffective treatment.
(d) Use of coagulants. Coagulants and filter aids may be mixed with
filter feed prior to filtration. Their effect is particularly
significant for vacuum filtration since they may make the difference
between no cake and a relatively dry cake in a vacuum filter. In a
pressure filter, coagulants and filter aids will also significantly
improve hydraulic capacity and cake dryness. Filter aids, such as
diatomaceous earth, can be precoated on filters (vacuum or pressure) for
particularly difficult to filter sludges. The precoat layer acts
somewhat like an in-depth filter in that sludge solids are trapped in the
precoat pore spaces. Use of precoats and most coagulants or filter aids
significantly increases the amount of sludge solids to be disposed of.
However, polyelectrolyte coagulant usage usually does not increase sludge
volume substantially because the dosage is low.
Two rotary drum vacuum filters were used for the separation of solids
after the precipitation step. These filters operated between 18 and
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26 inches Hg vacuum, with filter cake being discharged continuously. The
filter cake contained about 20 to 40 weight percent total dry solids.
The filtration rate was about 40 gpm. The vacuum filters were precoated
with diatomaceous earth and rotated at 1.07 to 1.3 rpm.
3.2.4 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 metals
recovery systems. 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, the 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 the untreated metal. Retorting is discussed in a separate
technology section.
(1) Applicability and use of this technology. This process is
applicable to wastes containing BOAT list metals, low water content (or a
water content that can be either blended to the required level or lowered
by dewatering), and low concentration of organics. This technology is
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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 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 underlying 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 as well. In such cases, the HTMR process can yield two
recoverable 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 the waste material that is not volatilized.
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(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 simply reflected 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 residual. 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
steelmaking); (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 recovered for use in the
manufacture of stainless steel); and (3) the material has no recoverable
value and is land disposed as a slag.
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(3) Description of the 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 residual. A generic schematic diagram for high temperature
metals recovery is shown in Figure 3-5.
(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 to prevent 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 to ensure the maximum
volatilization of the metal constituents.
(c) Product collection system. The product collection system can
consist of either a condenser or a combination condenser and baghouse.
As noted previously, the particular system depends on whether the metal
is to be collected in the metallic form or as an oxide.
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K061
CARBON
FLUXES
(ADDITIVES).
FEED
BLENDING
HIGH
TEMPERATURE
PROCESSING
PRODUCT
COLLECTION
REUSE
RESIDUAL
COLLECTION
REUSE OR
LAND DISPOSAL
FIGURE 3-5 EXAMPLE HIGH TEMPERATURE METALS RECOVERY SYSTEM
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(d) Handling the less volatile treated residual. The equipment
needed to handle the less volatile metal-treated residual depends on the
final disposition of the material. If further recovery is 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) Vlaste 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
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volatility of a particular constituent in a given waste. EPA believes
that the best measure of volatility of a specific metal constituent is
the boiling point. EPA recognizes that the boiling point has certain
shortcomings, primarily the fact that boiling points are given for pure
components, while it is clear that other constituents in the waste will
also affect partial pressures and thus 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. The constituents being recovered from
the waste must be heated near or above their boiling points in order for
them to be volatilized and recovered. Whether sufficient heat will be
transferred to the particular constituent to cause the metal to
volatilize will depend on the heat transfer characteristics of the
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 C of this document.
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(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 (a) the furnace
temperature, (b) the furnace residence time, (c) the amount and ratio of
the feed blending materials, and (d) mixing. Below is an explanation of
why EPA believes these parameters are important to an analysis of the
design and operation of the system.
(a) Furnace temperature. In order 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
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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
needed to adjust the following feed parameters to the required volume:
carbon content, moisture content, calcium-to-silica ratio, and the
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.
3.2.5 Stabilization
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
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the broader class of stabilization. Related technologies are
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 this technology. 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
that contain BOAT list metals and have 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 in order 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
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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.
(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 to 1500°C). 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
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so upon the addition of lime. Metals in the waste are converted to
silicates or hydroxides that inhibit leaching. Additives, again, can be
used to reduce permeability and thereby further decrease leaching
potential.
(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.
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
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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 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 1ime/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
and thereby decrease the resistance of the material to leaching.
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(c) Organic compounds. The presence of organic compounds in the
waste interferes with the chemical reactions and bond formation that
inhibit curing of the stabilized material. This results in a stabilized
waste that has 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.
(5) Design and operating parameters. In designing a stabilization
system, the principal parameters that must be optimized so that the
amount of Teachable metal constituents is minimized are (a) selection of
stabilizing agents and other additives, (b) ratio of waste to stabilizing
agents and other additives, (c) degree of mixing, and (d) 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 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
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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 and a
Portland cement-based system.
In order 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 additives. The amount of
stabilizing agents and additives is a critical parameter in that
sufficient stabilizing materials are necessary in the mixture to properly
bind the waste constituents of concern, 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
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 important,
may not allow the chemical reactions that bind the hazardous constituents
to be fully completed.
(c) Mixing. Mixing is necessary to ensure homogeneous distribution
of the waste and the stabilizing agents. Conditions include the type and
duration of mixing. Both undermixing and overmixing are undesirable.
The first condition results in a nonhomogeneous mixture; therefore, areas
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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 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 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. If temperatures are too high, however, the
evaporation rate can be excessive and result in too little water being
available for completion of the stabilization reaction. The duration of
the curing process should also be determined during the design stage and
typically will be between 7 and 28 days.
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3.3 Data Base
For the treatment system tested by the Agency, Tables 3-1 to 3-11
provide concentrations of BOAT list metals present in the untreated waste
streams, the treated wastewater, and the total concentration and the TCLP
values of the treated nonwastewater (cake). The untreated waste streams
are mixed and then processed in the treatment system. The composition of
the waste stream resulting from the mixing is also shown in Tables 3-1 to
3-11. The treated K062 wastewater is the filtrate from the vacuum
filter, and the treated K062 nonwastewater (cake) is the filter cake from
the vacuum filter. In the data from the 11 sample sets, chromium,
copper, and nickel were present in the highest concentrations in the
untreated K062 waste. The concentration data for the untreated waste
also show that arsenic and zinc were present in much lower concentrations.
The chemical precipitation treatment operations on all 11 sets were
carried out in the design pH range of 8 to 10.
As described in Section 3.2, the waste characteristics affecting
chromium reduction, chemical precipitation, and precipitate dewatering
for the untreated waste K062 are suspended solids concentration,
dissolved solids concentration, oil and grease content, and complexed
metal concentration. For suspended solids, the observed concentrations
in the untreated waste were <1 to 100 mg/1; for dissolved solids, 1900 to
118,100 mg/1; and for oil and grease, <0.2 to 6 mg/1; tests for metal
complexes were not performed.
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A comment received on the Notice of Availability and Request for
Comments on the California List Constituents (51 FR 2991) suggested that
K062 wastewaters and nonwastewaters can be treated by high temperature
metals recovery. The Agency, therefore, is including high temperature
metals recovery as a demonstrated treatment technology for K062
nonwastewaters. The Agency has requested data describing the performance
achievable by high temperature metals recovery. Upon review of the data
submitted, the Agency may promulgate final standards based on high
temperature metals recovery.
The performance data for the system tested by the Agency indicate
that the system appears to be well designed and well operated. The low
concentration of BOAT list metals in treated wastewaters and low TCLP
metal values for treated nonwastewaters show that the K062 waste was
effectively treated. Therefore, chromium reduction and chemical
precipitation, followed by dewatering of the precipitate, is a
demonstrated technology for K062 wastes.
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IRON-BEARING ACID
LIME SLURRY
1
o WASTE
^ STREAM
K062
^
CHROMIUM
REDUCTION
^
CHEMICAL
PRECIPITATION
»-
VACUUM
FILTRATION
»-
FILTRATE TO
^•MUNICIPAL
SEWER
CAKE TO
METALS
RECOVERY
FIGURE 3-6 SCHEMATIC DIAGRAM OF TREATMENT PROCESS FOR KO62 WASTES
-------
1665g
Table 3-1 Treatment Performance Data for
K062 - EPA-Collected Data
Sample Set #1
Constituent
Arsenic
Chromium (hexavalent)
Chromium (total)
Copper
Lead
Nickel
Zinc
Untreated
K062 waste
(mg/1)
Sample no.
801
3
I
1800
865
<10
3200
<2
Design
Untreated
K062 waste
(mg/1)
Sample no.
802
<1
I
7000
306
<10
2600
<2
Design
value
Untreated
waste
composite
(mg/1)
Sample no.
805
<1
893
2581
138
64
471
116
Treated
waste
(wastewater)
(rag/D
Sample no.
806
<0.1
0.011
0.12
0.21
<0.01
0.33
0.125
Treated waste K.062
(nonwastewater)
Total TCLP
(mg/kg) (mg/1)
Sample no.
807 807
<1
1.43
7300
380
2800
1400
1300
<0.010
-
<0.050
-
<0.10
-
-
and Operating Data
Operating
value
8-10
aThe untreated waste composite is a mixture of the untreated K062 waste streams shown on this table, along with other
non-K062 waste streams.
I = Color Interference.
- = Not Analyzed.
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1665g
Table 3-2 Treatment Performance Data for
K062 - EPA-Collected Data
Sample Set #2
Constituent
Arsenic
Chromium (hexavalent)
Chromium (total)
Copper
Lead
Nickel
Zinc
Untreated
K062 waste
(mg/1)
Sample no.
801
3
I
1800
865
<10
3200
<2
Desiqn
Untreated
K062 waste
(mg/1)
Sample no.
802
<1
I
7000
306
<10
2600
<2
Design
value
Untreated
waste
compos itea
(mg/1)
Sample no.
813
<1
807
2279
133
54
470
4
and Operating
Treated
waste
(wastewater)
(mg/1)
Sample no.
814
<0.1
0.12
0.19
0.15
<0.01
0.33
0.115
Data
Treated waste K062
Total TCLP
(mg/kg) (mg/1)
Sample no.
815 815
1
1.04
7400
400
1200
1200
2100
<0.010
-
<0.050
-
<0.10
-
-
Operating value
8-10
aThe untreated waste composite is a mixture of the untreated K.062 waste streams shown on this table, along with other
non-K062 waste streams.
I = Color Interference.
- = Not Analyzed.
104
-------
1665g
Table 3-3 Treatment Performance Data for
K062 - EPA-Collected Data
Sample Set #3
Constituent
Arsenic
Chromium (hexavalent)
Chromium (total)
Copper
Lead
Nickel
Zinc
Untreated
K062 waste
(mg/1)
Sample no.
817
3
I
1700
425
<10
100310
7
Design
Untreated
K.062 waste
(mg/1)
Sample no.
802
<1
I
7000
306
<10
2600
<2
Design
value
Untreated
waste
composite3
(mg/D
Sample no.
821
<1
775
1990
133
<10
16330
3.9
Treated
waste
(wastewater)
(mg/1)
Sample no.
822
<0.1
I
0.20
0.21
<0.01
0.33
0.140
Treated waste K062
Total TCLP
(mg/kg) (mg/1)
Sample no.
823 823
2
I
4000
445
118
3900
112
0.012
-
<0.050
-
<0.10
-
-
and Operating Data
Operating
value
pH
8-10
10
aThe untreated waste composite is a mixture of the untreated K062 waste streams shown on this table, along with other
non-K062 waste streams.
I = Color Interference.
- = Not Analyzed.
105
-------
1665g
Table 3-4 Treatment Performance Data for
K062 - EPA-Collected Data
Sample Set #4
Constituent
Arsenic
Chromium (hexavalent)
Chromium (total)
Copper
Lead
Nickel
Zinc
Untreated
K062 waste
(mg/1)
Sample no.
827
2
1
142
42
<10
650
3
Design
Untreated
K062 waste
(mg/D
Sample no.
802
<1
I
7000
306
<10
2600
<2
Design
value
Untreated
K062 waste
(mg/1)
Sample no.
817
3
I
1700
425
<10
41000
7
Untreated
waste
composite3
(mg/1)
Sample no.
829
<1
0.6
556
88
<10
6610
84
Treated
waste
(wastewater)
(mg/1)
Sample no.
830
<1
0.042
0.10
0.07
<0.01
0.33
1.62
Treated Waste K062
Total TCLP
(mg/kg) (mg/1)
Sample no.
831 831
2
0.92
2400
292
99
2700
1200
0.015
-
0.068
-
<0.10
-
-
and Operating Data
Operat ing
value
pH
8-10
aThe untreated waste composite is a mixture of the untreated K062 waste streams shown on this table, along with other
non-K062 waste streams.
I = Color Interference.
- = Not Analyzed.
106
-------
Ib6bg
Table 3-5 Treatment Performance Data for
K062 - EPA-Collected Data
Sample Set #5
Constituent
Arsenic
Chromium (hexavalent)
Chromium (total)
Copper
Lead
Nickel
Zinc
Untreated
K.062 waste
(mg/1)
Sample no.
801
3
I
1800
865
<10
3200
<2
Design
Untreated
K062 waste
(mg/1)
Sample no.
802
<1
I
7000
306
<10
2600
<2
Design
value
Untreated
K062 waste
(mg/1)
Sample no.
817
3
I
1700
425
<10
41000
7
Untreated
waste
composite3
(mg/1)
Sample no.
837
<1
917
2236
91
18
1414
71
Treated
waste
(wastewater)
(mg/1)
Sample no.
838
<0.1
0.058
0.11
180.14
0.01
0.31
0.125
Treated waste K062
Total TCLP
(mg/kg) (mg/1)
Sample no.
839 839
1
0.741
11500
375
525
3300
410
<0.010
-
<0.050
-
<0.10
-
-
and Operating Data
Operating
value
pH
8-10
aThe untreated waste composite is a mixture of the untreated K062 waste streams shown on this table, along with other
non-K062 waste streams.
I = Color Interference.
- = Not Analyzed.
107
-------
1665g
Table 3-6 Treatment Performance Data for
K062 - EPA-Collected Data
Sample Set #6
Constituent
Arsenic
Chromium (hexavalent)
Chromium (total)
Copper
Lead
Nickel
Zinc
Untreated
K062 waste
(mg/1)
Sample no.
801
3
I
1800
865
<10
3200
<2
Untreated
K062 waste
(mg/1)
Sample no.
802
<1
I
7000
306
<10
2600
<2
Design
Untreated
waste
composite3
(mg/1)
Sample no.
845
<1
734
2548
149
<10
588
4
and Operating
Treated
waste
(wastewater)
(mg/1)
Sample no.
846
<0.1
I
0.10
0.12
<0.01
0.33
0.095
Data
Treated waste
Total
(mg/kg)
K062
TCLP
(mg/1)
Sample no.
847
1
1.775
10000
432
42
1600
68
847
<0.010
-
<0.050
-
<0.10
-
-
pH
Design value
8-10
Operating value
aThe untreated waste composite is a mixture of the untreated K062 waste streams shown on this table, along with other
non-K.062 waste streams.
I = Color Interference.
- = Not Analyzed.
108
-------
1665g
Table 3-7 Treatment Performance Data for
K062 - EPA-Collected Data
Sample Set #7
Constituent
Arsenic
Chromium (hexavalent)
Chromium (total)
Copper
Lead
Nickel
Zinc
Untreated
K062 waste
(mg/1)
Sample no.
801
3
I
1800
865
<10
3200
<2
Design
Untreated
K.062 waste
(mg/1)
Sample no.
802
<1
I
7000
306
<10
2600
<2
Design
value
Untreated
waste
composite3
(mg/1)
Sample no.
853
<1
769
2314
72
108
426
171
Treated
waste
(wastewater)
(mg/1)
Sample no.
854
<0.1
0.12
0.12
0.16
<0.01
0.40
0.115
Treated Waste K062
Total TCLP
(mg/kg) (mg/1)
Sample no.
855 855
1
I
16300
330
375
1700
375
<0.010
-
<0.050
-
<0.10
-
-
and Operating Data
Operating
value
8-10
The untreated waste composite is a mixture of the untreated K062 waste streams shown on this table, along with other
non-K062 waste streams.
I = Color Interference.
- = Not Analyzed.
109
-------
1665g
Table 3-8 Treatment Performance Data for
K062 - EPA-Collected Data
Sample Set #8
Constituent
Arsenic
Chromium (hexavalent)
Chromium (total)
Copper
Lead
Nickel
Zinc
Untreated
K062 waste
(mg/1)
Sample no.
859
<1
0.220
15
151
<10
90
7
Design
Untreated
K062 waste
(mg/1)
Sample no.
801
3
I
1800
865
<10
3200
9
Design
value
Untreated
waste
composite3
(mg/1)
Sample no.
861
<1
0.13
831
217
212
669
151
and Operating
Treated
waste
(wastewater)
(mg/1)
Sample no.
862
<0.1
<0.01
0.15
0.16
<0.01
0.36
0.130
Data
Treated Waste K062
Total TCLP
(mg/kg) (mg/1)
Sample no.
863 863
4
0.116
2800
688
300
2600
420
0.011
-
<0.050
-
<0.10
-
-
Operating value
8-10
The untreated waste composite is a mixture of the untreated K062 waste streams shown on this table, along with other
non-K062 waste streams.
I = Color Interference.
- = Not Analyzed.
110
-------
i665g
Table 3-9 Treatment Performance Data for
K062 - EPA-Collected Data
Sample Set #9
Constituent
Arsenic
Chromium (hexavalent)
Chromium (total)
Copper
Lead
Nickel
Zinc
Untreated
K062 waste
(mg/D
Sample no.
867
<0.1
0.079
6
5
<1
4
0.4
Untreated
K062 waste
(mg/D
Sample no.
801
3
I
1800
865
<10
3200
<2
Design
Untreated
K062 waste
(mg/D
Sample no.
802
<1
I
7000
306
<10
2600
<2
and Operating
Untreated
waste
composite
(mg/1)
Sample no.
869
<1
0.07
939
225
<10
940
5
Data
Treated
waste
(wastewater)
(mg/1)
Sample no.
870
<0.1
0.041
0.10
0.08
<0.01
0.33
0.06
Treated Waste K062
Total
(mg/kg)
Sample
871
3
I
3400
775
85
3500
150
TCLP
(mg/1)
no.
871
0.011
-
<0.050
-
<0.10
-
-
PH
Design value
8-10
Operating value
10
The untreated waste composite is a mixture of the untreated K062 waste streams shown on this table, along with other
non-K062 waste streams.
I = Color Interference.
- = Not Analyzed.
Ill
-------
1665g
Table 3-10 Treatment Performance Data for
K062 - EPA-Collected Data
Sample Set #10
Constituent
Arsenic
Chromium (hexavalent)
Chromium (total)
Copper
Lead
Nickel
Zinc
Untreated
K062 waste
(mg/1)
Sample no.
801
<3
I
1800
865
<10
3200
<2
Design
Untreated
waste
compos i te
(mg/1)
Sample no.
885
<1
0.08
395
191
<10
712
5
Design and
value
Treated
waste
(wastewater)
(mg/1)
Sample no.
862
<0.10
0.106
0.12
0.14
<0.01
0.33
0.070
Operating Data
Operating
Treated Waste K062
Total TCLP
(mg/kg) (mg/1)
Sample no.
863 863
5
0.078
4400
758
28
4700
43
value
0.016
-
<0.050
-
<0.10
-
-
pH
8-10
aThe untreated waste composite is a mixture of the untreated K062 waste streams shown on this table, along with other
non-K062 waste streams.
I = Color Interference.
- = Not Analyzed.
ii'2
-------
1665g
Table 3-11 Treatment Performance Data for
K062 - EPA-Collected Data
Sample Set #11
Constituent
Arsenic
Chromium (hexavalent)
Chromium (total)
Copper
Lead
Nickel
Zinc
Untreated
K062 waste
(mg/1)
Sample no.
801
3
I
1800
865
<10
3200
<2
Design
Untreated
K062 waste
(mg/1)
Sample no.
859
<1
0.220
15
151
<10
90
7
Design
value
Untreated
waste
composite3
(mg/1)
Sample no.
893
<1
0.30
617
137
136
382
135
Treated
waste
(wastewater)
(mg/1)
Sample no.
894
<0.10
<0.01
0.18
0.24
<0.01
0.39
0.100
Treated Waste K062
Total TCLP
(mg/kg) (mg/1)
Sample no.
895 895
3
1.240
2100
388
200
1600
325
<0.010
-
<0.050
-
<0.10
-
-
and Operating Data
Operating
value
pH
8-10
The untreated waste composite is a mixture of the untreated K062 waste streams shown on this table, along with other
non-K062 waste streams.
I = Color Interference.
- = Not Analyzed.
113
-------
4. IDENTIFICATION OF BEST DEMONSTRATED AND AVAILABLE TECHNOLOGY (BOAT)
4.1 Introduction
This section presents the methodology for identifying BOAT based on
the treatment performance data collected for the demonstrated
technologies described in Section 3. This section provides EPA's
rationale for determining which of the demonstrated technologies
represents BOAT. As discussed in the previous section, the demonstrated
technologies for K062 are chromium reduction followed by chemical
precipitation and dewatering of the precipitate. In addition, the
wastewaters can be further treated using polishing filtration. For the
precipitated solids, i.e., the nonwastewaters, the demonstrated
technologies include metals recovery and stabilization. EPA tested a
treatment system consisting of chromium reduction, chemical
precipitation, and dewatering by vacuum filtration. We believe the
performance achieved by this treatment train represents BOAT; our
rationale is provided below.
4.1.1 Wastewaters
Regarding the wastewaters, the only applicable and demonstrated
technology beyond the tested technology is polishing filtration. EPA
does not expect this technology to significantly reduce the BOAT list
metals concentration to less than that achieved by the tested
technology. Therefore, EPA believes that this treatment train is the
"best" demonstrated technology for K062 wastewaters; that is, additional
treatment would not be expected to significantly improve the performance.
114
-------
4.1.2 Nonwastewaters
For nonwastewaters, the only applicable and demonstrated technologies
to be considered, in addition to the technology tested (i.e., chemical
precipitation), are stabilization and metals recovery. The Agency is
aware of a high temperature metals recovery process for the treatment of
K062 nonwastewaters. The Agency has requested data describing the
performance achievable by metals recovery and will reconsider this
technology when the data are received. Additional treatment by
stabilization is not expected to significantly reduce the Teachability of
the BOAT list metals present in treated K062 nonwastewaters. As
described in Section 1, the best demonstrated available technology (BOAT)
for treatment of these wastes is determined based on the performance data
presented in Section 3. Performance data are screened for poor design
and poor operation and are adjusted on the basis of the analytical
recovery values. Based on the performance data for the treatment train,
chromium reduction, chemical precipitation, and precipitate dewatering,
the Agency believes that the performance achieved by this treatment train
represents BOAT.
4.2 Determination of "Available"
As described in Secion 1, treatment standards will be based on
technologies that are determined to be available. Chromium reduction and
chemical precipitation followed by dewatering of the precipitate has been
determined to be demonstrated and available treatment technology since
(1) they are not proprietary or patented processes that cannot be
115
-------
purchased or licensed from the proprietor; and (2) they represent
substantial treatment since they significantly diminish the toxicity of
the waste or substantially reduce the likelihood that hazardous
constituents will migrate from the waste.
4.3 BOAT for K062 Wastes
The best demonstrated and available technology for K062 wastes has
been determined to be chromium reduction and chemical precipitation,
followed by dewatering of the precipitated solids. A schematic diagram
of this BOAT treatment train is presented in Figure 3-6.
116
-------
5. SELECTION OF REGULATED CONSTITUENTS
5.1 Introduction
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. The list is a "growing list," which means it
does not preclude the addition of new constituents as additional key
parameters are identified. The list is divided into the following
categories: volatile organics, semivolatile organics, metals, other
inorganics, organochlorine pesticides, phenoxyacetic acid herbicides,
organophosphorous pesticides, PCBs, and dioxins and furans.
This section describes the step by step process used to select the
pollutants to be regulated. The selected pollutants must be present in
the untreated waste and must be treatable by the chosen BOAT, as
discussed in Section 4.
5.2 Identification of Ma.lor Constituents in K062
In the previous section, the Agency selected the best demonstrated
treatment technology for treating K062 wastes. The constituents chosen
by the Agency for regulation are found in untreated wastes at treatable
concentrations for the selected BOAT. Based on the analysis of the
processes generating K062 wastes, as shown on the list of BOAT
constituents presented in Table 5-1 (232 in number), the Agency does not
expect that the following categories (containing 213 constituents) will
be present in K062 wastes: volatile organics, semivolatile organics,
organochlorine pesticides, phenoxyacetic acid herbicides,
117
-------
organophosphorous pesticides, PCBs, and dioxins and furans. Therefore,
the abovementioned categories were not analyzed for in the K062 wastes
tested by the Agency. Furthermore, the Agency has no data indicating
that these categories would be present in K062 wastes. The remaining
19 constituents fall into the categories of metals and other inorganics.
5.2 Selection of Regulated Constituents
As discussed in Section 2, K062 primarily contains metals, other
inorganics, and water. Of the 16 metals in the BOAT list of
constituents, the Agency has data showing that antimony, barium,
beryllium, cadmium, mercury, selenium, silver, and thallium, are present
below detectable levels in K062 wastes. However, the Agency does not
believe that these metals are present at levels treatable by the chosen
BOAT. Although vanadium was not analyzed for in the K062 waste tested by
the Agency, it is not expected that vanadium will be present in K062
wastes at treatable levels. The metals found in treatable concentrations
in the untreated K062 waste tested by the Agency are chromium, copper,
and nickel. Data are also available that indicate that lead may be
present at significant (i.e., treatable) concentrations in K062 wastes
from pickling operations from leaded steels. Arsenic and zinc were
detected at relatively low concentrations in the untreated waste tested
by the Agency, and are expected to be treated along with the metals
present at higher concentrations. Hexavalent chromium was detected at
less than 1 mg/1 in the untreated K062 waste for some data sets; for
118
-------
others, color interference prevented the analyses for hexavalent
chromium. Based on these findings, the Agency has selected for
regulation the following metals from the BOAT list of constituents:
chromium, copper, lead, and nickel. The solubilities of all these metals
are lowest within the design and operating pH range for the BOAT, i.e., a
pH range of 8 to 10. For hexavalent chromium, the Agency expects that a
well-designed and well-operated chromium reduction system, included in
the selected BOAT treatment train, will treat any hexavalent chromium.
The Agency is not regulating any of the other three BOAT list
inorganic constituents that may be present in K062 wastes, as they will
not be treated by the chosen BOAT. If in the future the Agency finds
that these other inorganics require treatment, it will set treatment
standards at that time.
The following table shows the constituents to be regulated and
concentration ranges at which they have been reported in the data
available to the Agency.
Range present in the
List of regulated constituents untreated K062 waste (mq/1)
Chromium 6 to 7000
Copper 5 to 865
Lead 0.12 to 1550
Nickel 4 to 100,310
119
-------
1556g
Table 5-1 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
Acetonitri le
Acrolein
Acrylomtrile
Benzene
Bromodichloromethane
Bromomethane
n-Butyl alcohol
Carbon tetrachloride
Carbon disulfide
Chlorobenzene
2-Chloro-l,3-butadiene
Chlo rod ibromome thane
Chloroethane
2-Chloroethyl vinyl ether
Chloroform
Chloromethane
3-Chloropropene
1 , 2-Oibromo-3-chloropropane
1 , 2-0 i bromoethane
Dibromomethane
Trans- l,4-Dichloro-2-butene
Dlchlorodif luoromethane
1,1-Oichloroethane
1,2-Dichloroethane
1 , 1-Dichloroethy lene
Trans-1 ,2-Oichloroethene
1 . 2-Dichloropropane
Trans-1 ,3-Dichloropropene
cis-1 ,3-Oichloropropene
1,4-Oioxane
2-£thoxyethanol
Ethyl acetate
Ethyl benzene
Ethyl cyanide
Ethyl ether
Ethyl methacrylate
Ethylene oxide
lodomethane
Units
ppb
ppb
ppb
PPb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppfa
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
0 = Detected
NO = Not detected
NA = Not analyzed
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
120
-------
1556g
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
Volati les (continued)
Isobutyl alcohol
Methanol
Methyl ethyl ketone
Methyl isobutyl ketone
Methyl methacrylate
Methacrylomtri le
Methylene chloride
2-Nitropropane
Pyndine
1,1,1, 2-Tetrachloroethane
1,1,2 , 2-Tetrach loroethane
Tetrach loroethene
Toluene
Tribromomethane
1,1 ,1-Trich loroethane
1,1,2-Trichloroethane
Trichloroethene
Trichloromonof luoromethane
1,2,3-Tnchloropropane
l,l,2-Trichloro-l,2,2-trif luoro-
ethane
Vinyl chloride
1,2-Xylene
1,3-Xylene
1,4-Xylene
Semivolatiles
Acenaphthalene
Acenaphthene
Acetophenone
2-Acetylaminof luorene
4-Aminobiphenyl
Am 1 me
Anthracene
Aramite
Benz(a)anthracene
Benzal chloride
Benzenethiol
Deleted
Benzo(a)pyrene
Units
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb .
ppb
ppb
D = Detected
ND = Not detected
NA = Not anal>>ed
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
121
-------
1556g
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.
88
89.
90.
91
92.
93
94.
95.
96.
97.
98
99.
100.
101
Parameter
Semivolati les (continued)
Benzo(b)f luoranthene
Benzofghi Jperylene
Benzo(k)f luoranthene
p-Benzoquinone
B i s ( 2-ch loroethoxy Jinethane
Bis(2-chloroethyl) ether
Bis(2-chloroisopropyl) ether
Bis(2-ethylhexyl)phthalate
4-Bromophenyl phenyl ether
Butyl benzyl phthalate
2-sec-Butyl-4,6-dimtrophenol
p-Chloroam 1 ine
Chlorobenzilate
p-Chloro-m-cresol
2-Chloronaphthalene
2-Chlorophenol
3-Chloropropionitri le
Chrysene
ortho-Cresol
para-Cresol
Cyclohexanone
D i benz ( a , h ) anthracene
Dibenzo(a,e)pyrene
Dibenzo(a, i Ipyrene
m-Dichlorobenzene
o-Dichlorobenzene
p-Oichlorobenzene
3,3'-Oichlorobenzidine
2,4-Dichlorophenol
2,6-Dichlorophenol
Diethyl phthalate
3,3'-Dimethoxybenzidine
p-D imethy lami noazobenzene
3,3'-Dimethylbenzidine
2,4-Dimethylphenol
Dimethyl phthalate
Oi-n-butyl phthalate
1 ,4-Dinitrobenzene
4,6-Dimtro-o-cresol
2,4-Dinitrophenol
Units
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
D = Detected
ND = Not detected
NA = Not analyzed
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
122
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1556g
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
Semivolati les (continued)
2,4-Oinitrotoluene
2,6-Oimtrotoluene
Di-n-octyl phthalate
Di-n-propylnitrosamine
Diphenylamme
D i pheny 1 n 1 1 rosam i ne
1 ,2-Diphenylhydrazine
Fluoranthene
Fluorene
Hexach lorobenzene
Hexachlorobutadiene
Hexachlorocycl open tad lene
Hexach loroethane
Hexach lorophene
Hexach loropropene
lndeno(l,2,3-cd)pyrene
Isosafrole
Methapyri lene
3-Methylcholanthrene
4,4'-Methylenebis
(2-chloroam 1 me)
Methyl methanesulfonate
Naphthalene
1 , 4-Naphthoqu i none
1-Naphthylamine
2-Naphthylamme
p-Nitroani line
Nitrobenzene
4-Nitrophenol
N-Nitrosodi-n-butylamme
N-Nitrosodiethylamine
N-N i t rosodi methyl am ine
N-Nitrosomethylethylamme
N-Nitrosomorphol me
N-Nitrosopipendme
n-Nitrosopyrrol idine
5-Nitro-o-toluidme
Pentach lorobenzene
Pentach loroethane
Pentach loron i t robenzene
Units
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
0 = Detected
NO = Not detected
NA = Not analyzed
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
123
-------
1556g
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)
Pentachlorophenol
Phenacetin
Phenanthrene
Phenol
Phthalic anhydride
2-Picoline
Pronamide
Pyrene
Resorcinol
Safrole
1,2,4, 5-Tetrachlorobenzene
2 , 3 , 4 , 6-Tet rach loropheno 1
1 ,2,4-Trichlorobenzene
2,4,5-Trichlorophenol
2,4,6-Trichlorophenol
Tr i s ( 2 , 3-d i bromopropy 1 )
phosphate
Hetals
Ant imony
Arsenic
Barium
Beryllium
Cadmium
Chromium (total)
Chromium (hexavalent)
Copper
Lead
Mercury
Nickel
Selenium
Si Iver
Thall lum
Vanadium
Zinc
Inorganics
Cyanide
Fluoride
Sulf ide
Units
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
10
*
10
2
5
10
1
10
2
10
2
D = Detected
ND = Not detected
NA = Not analyzed
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
ND
D
ND
ND
ND
D
D
D
ND
ND
D
ND
ND
ND
NA
D
ND
NA
D
124
-------
1556g
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
137.
198.
199
200.
201
202.
Parameter
Oroanochlorine pesticides
Aldnn
alpha-BHC
beta-BHC
delta-BHC
gamma-BHC
Chlordane
ODD
DDE
DDT
Dieldrin
Endosulfan I
Endosulfan II
Endrin
Endnn aldehyde
Heptachlor
Heptachlor epoxide
Isodrin
Kepone
Methoxyclor
Toxaphene
Phenoxyacetic acid herbicides
2,4-Dichlorophenoxyacetic acid
Si Ivex
2,4.5-T
Orqanoohosphorous insecticides
Disulfoton
Famphur
Methyl parathion
Parathion
Phorate
PCBs
Aroclor 1016
Aroclor 1221
Aroclor 1232
Units
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
ppb
D = Detected
NO = Not detected
NA = Not analyzed
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
125
-------
1556g
Table 5-1 (continued)
BOAT
reference
no.
Parameter
D = Detected
Unit ND = Not detected
NA = Not analyzed
PCBs (continued)
203.
204.
205.
206.
Aroclor 1242
Aroclor 1248
Aroclor 1254
Aroclor 1260
ppb
ppb
ppb
ppb
NA
NA
NA
NA
207.
208.
209
210.
211.
212.
213.
Dioxins and furans
Hexachlorodibenzo-p-dioxins ppb
Hexachlorodibenzofurans ppb
Pentachlorodibenzo-p-dioxins ppb
Pentachlorodlbenzofurans ppb
Tetrachlorodibenzo-p-dioxins ppb
Tetrachlorodibenzofurans ppb
2,3,7,8-Tetrachlorodibenzo-p-dioxin ppb
NA
NA
NA
NA
NA
NA
NA
* Five samples had a detection limit of 1 mg/1 and one had 0.1 mg/1
D = Detected
ND = Not detected
NA = Not analyzed
126
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6. CALCULATION OF BOAT TREATMENT STANDARDS
In the previous section, EPA chose the constituents in the untreated
i
K062 waste to be regulated. The purpose of this section is to calculate
treatment standards for those regulated constituents. Details of the
methodology are provided in "Generic Quality Assurance Project Plan
(QAPP) for the Land Disposal Restriction Program (BOAT)," March 1987. As
discussed in Section 5, the regulated constituents are chromium, copper,
lead, and nickel.
The BOAT treatment standards (1) are reflective of treatment data
from a well-designed and well-operated treatment system, (2) account for
analytical limitations, and (3) have been adjusted for variability owing
to treatment, sampling, and analytical techniques and procedures.
The BOAT treatment standards for K062 were derived as follows.
6.1 Correction of the Analytical Data
The raw analytical data for the regulated constituents for K062 were
corrected for the analytical recovery by multiplying by their respective
recovery-correction factors. The recovery-correction factors are
obtained by dividing 100 by the corresponding percent recovery of the
constituents. Presently the percent recovery values for the regulated
K062 constituents are being taken from the Onsite Engineering Report for
Horsehead for K061 (USEPA 1987), since percent recovery values are not
available for metal spikes and metal spike duplicates from the treatment
data on K062. This is being done since all the metals that are being
regulated in K062 were also analyzed for in K061. However, for K061,
127
-------
ICP Method 6010 (SW-846) was used to analyze for chromium, copper, lead,
and nickel, whereas for K062, analysis for chromium was by Method 7190
(atomic absorption), copper by Method 220.1 (atomic absorption), lead by
Method 7420 (atomic absorption), and nickel by Method 7520 (atomic
absorption). The transferred percent recovery values for total
composition are 68, 83, 76, and 93 percent for chromium, copper, lead,
and nickel, respectively. The transferred percent recovery value for
TCLP for chromium and lead are 68 and 76 percent, respectively. The
corrected concentration values for the regulated constituents in the
treated wastewater residuals are presented in Table 6-1. The corrected
TCLP values in the treated nonwastewater residuals are provided in
Table 6-2.
6.2 Calculation of Variability Factors and Treatment Standards
Details of the treatment standard calculation methodology are given
in Section 1. In summary, average values of corrected concentrations of
the regulated pollutants in the treated residuals for the 11 data sets
were calculated. Variability factors were then calculated by determining
the logarithm of the concentration values of the regulated constituents
in the treated wastewater residual stream and also for the TCLP values of
the treated nonwastewater residual stream. Following this, their
logarithmic mean and logarithmic standard deviation were calculated. All
these values were then applied to the formula for variability factor
calculation (given in Appendix A). Table 6-3 presents the concentration
of the regulated constituents for each treated wastewater sample. The
table also shows the mean value, the calculated variability factor, and
128
-------
the treatment standard. The treatment standard is the product of the
mean concentration and the variability factor. Table 6-4 shows the same
procedure for the treated nonwastewater residual leachate (TCLP).
The Agency does not have treatment performance data on the treatment
of K062 wastes containing lead. Therefore, the Agency is transferring
treatment data for lead from lead-containing non-K062 wastes treated at
Envirite, along with the K062 wastes tested by the Agency. The Agency
expects that the mixed wastes referred to above, are at least as
difficult to treat as K062 wastes containing lead. Accordingly, EPA
believes that the level of performance achieved for lead in the wastes
treated in the treatment system tested by the Agency, can be transferred
to lead in K062 wastes. EPA requests comments on its assertion that the
waste for which we have treatment data would be as difficult to treat as
lead-containing K062 wastes.
In summary, the BOAT treatment standards for K062 are as follows:
Treated residual Treated residual
(wastewater) (nonwastewater)
Constituent total concentration (mq/1) TCLP (mq/1)
Chromium (total) 0.32 0.094
Copper 0.42
Lead 0.04 0.37
Nickel 0.44
129
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1666g
Table 6-1 Calculation of Corrected Values for Regulated Constituents
for Treated Wastewaters - Total Composition
Treated waste
Constituent (ntg/1)
Chromium (total) 0.12
0.12
0.20
0.10
0.11
0.10
0.12
0.15
0.10
0.12
0.18
Copper 0.21
0.15
0.21
0.07
0.14
0.12
0.16
0.16
0.08
0.14
0.24
Lead <0.01
<0.01
<0.01
<0.01
0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
Percent3 Correction Corrected value
recovery factor (mg/1)
68 1.47 0.1764
0.1764
0.294
0.147
0.162
0.147
0.1764
0.2205
0.147
0.1764
0.2646
83 1.205 0.253
0.181
0.253
0.084
0.1687
0.145
0.193
0.193
0.096
0.1687
0.2892
76 1.316 <0.0132
<0.0132
<0.0132
<0.0132
0.0132
<0.0132
<0.0132
<0.0132
<0.0132
<0.0132
<0.0132
130
-------
1666g
Table 6-1 (continued)
Treated waste
Constituent (mg/1)
Nickel 0.33
0.33
0.33
0.33
0.31
0.33
0.40
0.36
0.33
0.33
0.39
Percent3 Correction Corrected value
recovery factor ' (mg/1)
93 1.075 0.35
0.35
0.35
0.35
0.33
0.35
0.43
0.39
0.35
0.35
0.42
aThe percent recovery has been taken from Table 7-14 of the Onsite Engineering
Report from Horsehead Resource Development Company. U.S. EPA 1987.
131
-------
1666g
Table 6-2 Calculation of Corrected Values for Regulated
Constituents for Treated Nonwastewaters - TCLP Values
Treated waste
Constituent (cake) TCLP(mg/l)
Chromium (total) <0.050
<0.050
<0.050
0.068
<0.050
<0.050
<0.050
<0.050
<0.050
<0.050
<0.050
Lead <0.10
<0.10
<0.10
<0.10
<0.10
<0.10
<0.10
<0.10
<0.10
<0.10
<0.10
Percent3 Correction Corrected
recovery factor value
(ing/1)
68 1.47 <0.0735
<0.0735
<0.0735
0.1000
<0.0735
<0.0735
<0.0735
<0.0735
<0.0735
<0.0735
<0.0735
76 1.316 <0.132
<0.132
<0.132
<0.132
<0.132
<0.132
<0.132
<0.132
<0.132
<0.132
<0.132
aThe percent recovery has been taken from Table 7-14 of the Onsite Engineering
Report from Horsehead Resource Development Company. U.S. EPA 1987.
132
-------
1535g
Table 6-3 Calculation of the Treatment Standards for the
Regulated Constituents - Treated Wastewaters
Treatment standard
Regulated total concentration
constituent Cone. Mean VF (mg/1)
Chromium (total) .1765 .1898 1.69 0,32
.1765
.2941
.1471
.1618
.1471
.1765
.2206
.1471
.1765
.2647
Copper .2530 .1840 2.30 0.42
.1807
.2530
.0843
.1687
.1446
.1928
.1928
.0964
.1687
.2892
Lead <0.0132 0.0132 2.8a 0.04
<0.0132
<0.0132
<0.0132
0.0132
<0.0132
<0.0132
<0.0132
<0.0132
<0.0132
<0.0132
133
-------
1535g
Table 6-3 (continued)
Treatment standard
Regulated total concentration
constituent Cone. Mean VF (mg/1)
Nickel .3548 .3685 1.20 0.44
.3548
.3548
.3548
.3333
.3548
.4301
.3871
.3548
.3548
.4194
aFor cases in which all values are at or below the detection limit, the
variability factor is taken as 2.8.
134
-------
1535g
Table 6-4 Calculation of the Treatment Standards for the
Regulated Constituent - Treated Nonwastewaters
Regulated
constituent
Chromium (total)
Lead
Cone . Mean VF
<0.0735 0.0759 1.24
<0.0735
<0.0735
0.1
<0.0735
<0.0735
<0.0735
<0.0735
<0.0735
<0.0735
<0.0735
<0.132 0.132 2.8a
<0.132
<0.132
<0.132
<0.132
<0.132
<0.132
<0.132
<0.132
<0.132
<0.132
Treatment standard
TCLP values
(mg/1)
0.094
0.37
For cases in which all values are at or below the detection limit, the
variability factor is taken as 2.8.
135
-------
7. CONCLUSION
The Agency has proposed treatment standards for the listed waste code
K062 from the steel industry. Standards for nonwastewater forms of these
wastes are presented in Table 7-1, while standards for wastewater forms
of these wastes are shown in Table 7-2.
The treatment standards proposed for K062 have been developed
consistent with EPA's promulgated methodology for BOAT (November 7, 1986,
51 FR 40572). K062 wastes are generated by the steel industry from steel
finishing operations. K062 wastes are primarily comprised of BOAT list
metals, water, and other inorganics. Although the concentrations of
specific constituents will vary from facility to facility, all of the
wastes are expected to contain similar BOAT list metals, have low
filterable solids content, and are expected to be treatable to the same
levels using the same technology. The BOAT list constituents generally
present in K062 wastes are chromium, copper, lead, and nickel.
Through EPA's technology testing program, the Agency has identified
the following demonstrated technology for the treatment of metal
constituents present in the K062 wastes: chromium reduction, chemical
precipitation, and dewatering of the precipitate. Stabilization is a
potentially applicable process for treatment of BOAT list metal
constituents in nonwastewater residues resulting from the dewatering of
the precipitated solids. Metals recovery from the filter cake resulting
from the dewatering step in the treatment of K062 waste is an applicable
and demonstrated technology for the recovery of metals. The Agency is
136
-------
presently collecting treatment data from the high temperature metals
recovery process for the recovery of metals from the filter cake from the
treatment of K062. For wastewaters resulting from the dewatering step,
polishing filtration is an applicable and demonstrated technology to
remove any BOAT list metals contained in the suspended solids in the
wastewaters.
Regulated constituents were selected based on a careful evaluation of
the constituents found at treatable levels in the untreated wastes and
constituents detected in the treated wastes. All available waste
characterization and applicable treatment data, consistent with the type
and quality of data needed by the Agency on this program, were used to
make this determination. Those constituents that were most indicative of
a well-designed, well-operated treatment system were chosen as the
regulated constituents. For K062 waste, those constituents also
represent the BOAT list constituents that the Agency believes will be
present at the highest concentrations. Some constituents present at
treatable concentrations in the untreated waste were not regulated if it
was determined that they would be adequately controlled by the regulation
of another constituent.
In the development of treatment standards for these wastes, the
Agency examined all available treatment data. The Agency conducted tests
on a full-scale treatment system consisting of chromium reduction,
chemical precipitation, and precipitate dewatering for K062 wastes.
Design and operating data collected during the testing of the treatment
technology train indicate that the treatment system was properly operated
137
-------
during each sample set. Accordingly, all of the treatment performance
data collected during the tests were used in the development of the BOAT
treatment standards.
Two categories of treatment standards were developed for wastes in
the K062 treatability group: wastewater and nonwastewater wastes. (For
the purpose of the land disposal restrictions rule, wastewaters are
defined as wastes containing less than 1 percent (weight basis)
filterable solids and less than 1 percent (weight basis) total organic
carbon.)
Treatment standards for these wastes were derived after adjustment of
laboratory data to account for recovery. The percent recovery values are
being transferred from testing and analysis results for K061 (emission
dust from electric arc furnaces) for corresponding metal constituents.
This was necessary because the laboratory results for percent recovery
values for the K062 treatment tests are not available. Subsequently, the
mean of the adjusted data points was multiplied by a variability factor
to derive the standard. The variability factor represents the
variability inherent in the treatment process and sampling and analytical
methods. Variability factors were determined by statistically
calculating the variability seen for a number of data points for a given
constituent.
Wastes determined to be K062 wastes may be land disposed if they meet
the standards at the point of disposal. The BOAT upon which the
treatment standards are based (chromium reduction and chemical
precipitation followed by precipitate dewatering) need not be
138
-------
specifically utilized prior to land disposal, provided an alternative
technology achieves the standards.
These standards become effective as of August 8, 1988, as per the
schedule set forth in 40 CFR 268.10. Consistent with Executive
Order 12291, EPA prepared a regulatory impact analysis (RIA) to assess
the economic effect of compliance with this proposed rule. The RIA
prepared for this proposed rule is available in the Administrative Record
for the First Sixths' Rule.
139
-------
1556g
Table 7-1
BOAT Treatment Standards
for
Nonwastewater K062 Wastes
Regulated Metal
Constituents TCLP (mg/1)
Chromium (total) 0.094
Lead 0.37
Table 7-2
BOAT Treatment Standards
for
Wastewater K062 Wastes
Regulated metal
constituents Total concentration (mg/1)
Chromium (total) 0.32
Copper 0.42
Lead 0.04
Nickel 0.44
140
-------
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Austin, G.T. 1984. Shreve's chemical process industries, 5th ed. New
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Bishop, P.L., Ransom, S.B., and Grass, D.L. 1983. Fixation mechanisms
in solidification/stabilization of inorganic hazardous wastes. In
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Purdue University, West Lafayette, Indiana.
Center for Metals Production. 1985. Electric arc furnace dust-disposal,
recycle and recovery, Pittsburgh, Pa: May 1985.
Cherry, Kenneth F. 1982. Plating waste treatment, pp. 45-67.
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Conner, J.R. 1986. Fixation and solidification of wastes. Chemical
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Cullinane, M.J., Jr., Jones, L.W., and Malone, P.G. 1986. Handbook for
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Cincinnati, Ohio: U.S. Environmental Protection Agency.
Cushnie, George C., Jr. 1984. Removal of metals from wastewater:
neutralization and precipitation, pp. 55-97. Park Ridge, N.J.: Noyes
Publications.
Cushnie, George C., Jr. 1985. Electroplating wastewater pollution control
technology, pp. 48-62, 84-90. Park Ridge, N.J.: Noyes Publications.
Duby, Paul. 1980. Extractive metallurgy. In Kirk-Othmer encyclopedia
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Sons.
Eckenfelder, W.W. 1985. Wastewater Treatment. Chemical Engineering
85:72.
141
-------
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.
Grain, Richard W. Solids 1981. Removal and concentration. In Third
Conference on Advanced Pollution Control for the Metal Finishing
Industry. Cincinnati, Ohio. U.S. Environmental Protection Agency.
pp. 56-62.
Gurnham, C.F. 1955. Principles of industrial waste treatment. New York;
John Wiley and Sons. pp. 224-234.
Kirk-Othmer. 1980. Encyclopedia of chemical technology. 3rd ed. Vol. 10.
New York: John Wiley and Sons.
Lanouette, Kenneth H. 1977. Heavy metals removal. Chemical Engineering
October 17, 1977, pp. 73-80.
Lloyd, Thomas. 1980. Zinc compounds. In Kirk-Othmer encyclopedia of
chemical technology. 3rd ed. Vol. 24, p. 856. New York: John Wiley
and Sons.
Lloyd, Thomas, and Showak, Walter, 1980. Zinc and zinc alloys. In
Kirk-Othmer encyclopedia of chemical technology. 3rd ed. Vol. 24, p.
824. New York: John Wiley and Sons.
Maczek, Helmut, and Kola, Rolf. 1980. Recovery of zinc and lead from
electric furnace steelmaking dust at Berzelius. Journal of Metals
32:53-58.
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.
Patterson, James W. 1985. Industrial wastewater treatment technology.
2nd ed. Stoneham, Mass.: Butterworth Publishers.
Perry, Robert H. and Chilton. Cecil H. 1973. Chemical engineers'
handbook. 5th ed. Section 19. New York: McGraw Hill, Inc.
Pojasek, R.B. 1979. Sol id-waste disposal: solidification. Chemical
Engineering 86(17):141-145.
Price, Laurence. 1986. Tensions mount in EAF dust bowl. Metal
producing. February 1986.
142
-------
Rudolfs, William. 1953. Industrial wastes. Their disposal and
treatment, p. 294. Valley Stream, N.Y.: L.E.C. Publishers Inc.
U.S. Department of Commerce, Bureau of the Census. 1984. 1982 Census of
manufacturers.
USEPA. 1980a. 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.
USEPA. 1980b. U.S. Environmental Protection Agency. RCRA listing
background document. Waste Code K062.
USEPA. 1982. U.S. Environmental Protection Agency. Final development
document for effluent limitations guidelines and standards for the iron
and steel manufacturing point source category salt bath descaling
subcategorv. Volume V. 440/1-82/024. Washington, D.C.: EPA Effluent
Guidelines Division. May 1982.
USEPA. 1983. U.S. Environmental Protection Agency. Treatability
manual, Volume III, Technology for control/removal of pollutants.
EPA-600/2-82/001C, January 1983. pp. III.3.1.3.2.
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report of treatment technology performance and operation for Envirite
Corporation. Prepared by Versar for Office of Solid Waste, USEPA,
under Contract No. 68-01-7053. December 1986.
USEPA. 1987. U.S. Environmental Protection Agency. Office of Solid Waste,
Onsite engineering report of treatment technology performance and
operation for Horsehead Resource Development Company.
Washington, D.C.: U.S. Environmental Protection Agency.
USEPA. U.S. Environmental Protection Agency. Characterization of waste
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Characterization and Assessment Division, U.S. Environmental Protection
Agency.
143
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APPENDIX A - Analysis of Variance Test and
Variability Factor Calculation
144
-------
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 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 Table A-l.) 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).
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
145
-------
Table A-l
» ...
95th PERCENTILE VALUES FOR
THE F DISTRIBUTION
ni — degrees of freedom for numerator
nz = degrees of freedom for denominator
_ . . . (shaded area = .95)
/^
FM
V
1
2
3
4
5
6
I
8
9
10
11
12
13
14
15
16
17
18
19
20
2°
24
26
28
30
40
50
60
70
80
100
150
200
400
00
1
161.4
18.51
10.13
7.71
6.61
5.99
5.59
5.32
5.12
4.96
4.84
4.75
4.67
4.60
4.54
4.49
4.45
4.41
4.38
4.35
4.30
4.26
4.23
4.20
4.17
4.08
4.03
4.00
3.98
3.96
3.94
3.91
3.89
3.86
3.84
2
199.5
19.00
9.55
6.94
5.79
5.14
4.74
4.46
4.26
4.10
3.98
3.89
3.81
3.74
3.68
3.63
3.59
3.55
3.52
3.49
3.44
3.40
3.37
3.34
3.32
3.23
3.18
3.15
3.13
3.11
3.09
3.06
3.04
3.02
2.99
3
215.7
19.16
9.28
6.59
5.41
4.76
4.35
4.07
3.86
3.71
3.59
3.49
3.41
3.34
3.29
3.24
3.20
3.16
3.13
3.10
3.05
3.01
2.98
2.95
2.92
2.84
2.79
2.76
2.74
2.72
2.70
2.67
2.65
2.62
2.60
4
224.6
19.25
9.12
6.39
5.19
4.53
4.12
3.84
3.63
3.48
3.36
3.26
3.18
3.11
3.06
3.01
2.96
2.93
2.90
2.87
2.82 .
2.78
2.74
2.71
2.69
2.61
2.56
2.53
2.50
2.48
2.46
2.43
2.41
2.39
2.37
5
230.2
19.30
9.01
6.26
5.05
4.39
3.97
3.69
3.48
3.33
3.20
3.11
3.03
2.96
2.90
2.85
2.81
2.77
2.74
2.71
2.66
2.62
2.59
2.56
2.53
2.45
2.40
2.37
2.35
2.33
2.30
2.27
2.26
2.23
2.21
6
234.0
19.33
8.94
6.16
4.95
4.28
3.87
3.58
3.37
3.22
3.09
3.00
2.92
2.85
2.79
2.74
2.70
2.66
2.63
2.60
2.55
2.51
2.47
2.45
2.42
2.34
2.29
2.25
2.23
2.21
2.19
2.16
2.14
2.12
2.09
8
238.9
19.37
8.85
6.04
4.82
4.15
3.73
3.44
3.23
3.07
2.95
2.85
2.77
2.70
2.64
2.59
2.55
2.51
2.48
2.45
2.40
2.36
2.32
2.29
2.27
2.18
2.13
2.10
2.07
2.05
2.03
2.00
1.98
1.96
1.94
12
243.9
19.41
8.74
5.91
4.68
4.00
3.57
3.28
3.07
2.91
2.79
2.69
2.60
2.53
2.48
2.42
2.38
2.34
2.31
2.28
2.23
2.18
2.15
2.12
2.09
2.00
1.95
1.92
1.89
1.88
1.85
1.82
1.80
1.78
1.75
16
246.3
19.43
8.69
5.84
4.60
3.92
3.49
3.20
2.98
2.82
2.70
2.60
2.51
2.44
2.39
2.33
2.29
2.25
2.21
2.18
2.13
2.09
2.05
2.02
1.99
1.90
1.85
1.81
1.79
1.77
1.75
1.71
1.69
1.67
1.64
20
248.0
19.45
8.66
5.80
4.56
3.87
3.44
3.15
2.93
2.77
2.65
2.54
2.46
2.39
2.33
2.28
2.23
2.19
2.15
2.12
2.07
2.03
1.99
1.96
1.93
1.84
1.78
1.75
1.72
1.70
1.68
1.64
1.62
1.60
1.57
30
250.1
19.46
8.62
5.75
4.50
3.81
3.38
3.08
2.86
2.70
2.57
2.46
2.38
2.31
2.25
2.20
2.15
2.11
2.07
2.04
1.98
1.94
1.90
1.S7
1.84
1.74
1.69
1.65
1.62
1.60
1.57
1.54
1.52
1.49
1.46
40
251.1
19.46
8.60
5.71
4.46
3.77
3.34
3.05
2.82
2.67
2.53
2.42
2.34
2.27
2.21
2.16
2.11
2.07
2.02
1.99
1.93
1.89
1.85
1.81
1.79
1.69
1.63
1.59
1.56
1.54
1.51
1.47
1.45
1.42
1.40
50
252.2
19.47
8.58
5.70
4.44
3.75
3.32
3.03
2.80
2.64
2.50
2.40
2.32
2.24
2.18
2.13
2.08
2.04
2.00
1.96
1.91
1.86
1.82
1.78
1.76
1.66
1.60
1.56
1.53
1.51
1.48
1.44
1.42
1.38
1.32
100
253.0
19.49
8.56
5.66
4.40
3.71
3.28
2.98
2.76
2.59
2.45
2.35
2.26
2.19
2.12
2.07
2.02
1.98
1.94
1.90
1.84
1.80
1.76
1.72
1.69
1.59
1.52
1.48
1.45
1.42
1.39
1.34
1.32
1.28
1.24
OC
254.3
19.50
8.53
5.63
4.35
3.67
3.23
2.93
2.71
2.54
2.40
2.30
2.2i
2.13
2.07
2.01
1.96
1.92
1.88
1.84
1.78
1.73
1.69
1.65
1.62
1.51
1.44
1.39
1.35
1.32
1.28
1.22
1.19
1.13
1.00
146
-------
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 logtransformed.
(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 =
where:
k = number of treatment technologies
n^ = number of data points for technology i
N = number of data points for all technologies
T^ = sum of natural logtransformed data points for each technology.
(iv) The sum of the squares within data sets (SSW) is computed:
k
I
i-l
V'
"T
r k
•E, TI
1=1
N
i ^
SSW =
where:
' k
.1
I1
j=l
1,J
k
- I
i=l
x-jj = 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.
-------
(vi) Using the above parameters, the F value is calculated as
follows:
MSB
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 where one
technology achieves significantly better treatment than the other
technology.
148
-------
1 790g
Example 1
Methylene Chloride
Steam stripping
Influent Effluent
Ug/U
1550.00
1290 00
1640 00
5100.00
1450.00
4600 00
1760 00
2400.00
4800.00
12100.00
(M9/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) [ln(eff luent)]2 Influent Effluent ln(ef fluent)
2.30
2.30
2.30
2.48
2.30
2.30
2.30
2.30
2.30
2.30
Ug/1) Ug/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
[In(effluent)]2
5.29
5.29
5.29
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
ANQVA Calculations.
SSB =
k n,
2 X
1=1
ssw =
MSB = SSB/(k-l)
MSW = SSW/(N-k)
'•
1)
k H'2
it
n,
149
-------
1790g
Example 1 (continued)
F = MSB/MSW
where.
k = number of treatment technologies
n = number of data points for technology i
N = number of natural log transformed data points for all technologies
T = sum of log transformed data points for each technology
i
X = the nat. log transformed observations (j) for treatment technology (i)
U
n = 10. n = 5, N = 15, k = 2. T = 23.18. T = 12.46. T = 35.64, T = 1270.21
T2 = 537.31 T2 = 155.25
. 537.31 155.25
SSB =j +
10 5
1270.21
15
= 0.10
10
= 0.77
MSB = 0.10/1 = 0.10
MSW = 0.77/13 = 0.06
0 10
F =
0.06
= 1.67
ANOVA Table
Source
Degrees of
freedom
SS
MS
Between(B)
Within(W)
1
13
0.10
0.77
0.10
0.06
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, 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.
150
-------
1790g
Example 2
Trichloroethylene
^team stripeing
Influent
Ug/D
1650.00
5200.00
5000.00
1720.00
1560 00
10300.00
210.00
1600.00
204 00
160.00
Effluent
Ug/D
10 00
10.00
10.00
10.00
10.00
10.00
10.00
27.00
85.00
10.00
ln(eff luent)
2.30
2.30
2.30
2.30
2.30
2.30
2.30
3.30
4.44
2.30
O(effluent)]2
5.29
5.29
5.29
5.29
5.29
5.29
5.29
10.89
19.71
5.29
Influent
Ug/D
200.00
224.00
134.00
150.00
484 . 00
163.00
182.00
Biological treatment
Effluent
Ug/D
10.00
10.00
10.00
10.00
16.25
10.00
10.00
In(effluent)
2.30
2.30
2.30
2.30
2 79
2.30
2.30
[In(effluent)]2
5.29
5.29
5.29
5.29
7.78
5.29
5.29
bum:
Sample Size-
10 10
Mean:
2760
19.2
Standard Deviation:
3209 6 23.7
Variability Factor:
26.14
10
2.61
.71
72.92
220
120.5
3.70
10.89
2.36
1.53
16.59
2.37
.19
39.52
ANOVA Calculations:
SSB =
SSW =
MSB = SSB/(k-l)
MSW = SSW/(N-k)
151
-------
1790g
Example 2 (continued)
F = MSB/MSW
where.
k = number of treatment technologies
n = number of data 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 = 10, N = 7, N = 17, k = 2. T = 26.14, T = 16.59, T = 42.73, T = 1825.85, T = 683.30.
T = 275.23
(683.30 275.23
SSB =| +
10 7
1825.85
17
= 0.25
SSW= (72.92. 39.52) -
10
= 4.79
MSB = 0.25/1 = 0.25
MSW = 4.79/15 = 0.32
F=!f_=0.78
0.32
ANOVA Table
Source
Degrees of
freedom
SS
MS
Between(B)
Within(W)
1
15
0.25
4.79
0.25
0.32
0.78
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.
152
-------
1790g
Example 3
Chlorobenzene
Activated sludqe followed
Influent Effluent
Ug/D Ug/1)
7200.00 80.00
6500.00 70.00
6075.00 35.00
3040.00 10.00
bv carbon adsorption Bioloqical treatment
In(effluent) [ln(eff luent)]2 Influent
Ug/D
4.38 19.18 9206.00
4.25 18.06 16646.00
3.56 12.67 49775.00
2.30 5.29 14731.00
3159.00
6756.00
3040.00
Effluent
(M9/1)
1083.00
709 . 50
460.00
142.00
603 . 00
153.00
17.00
In(effluent)
6.99
6.56
6.13
4.96
6.40
5.03
2.83
ln[(effluent)]2
48.86
43.03
37.58
24.60
40.96
25.30
8.01
Sum-
Sample Size:
4
Mean:
5703
49
Standard Deviation:
1835.4 32.24
Variabi1ity Factor:
14.49
3.62
.95
55.20
14759
16311.86
7 00
452.5
379.04
15.79
38.90
5.56
1.42
228.34
ANOVA Calculations:
SSB =
HI
A "
SSW -
MSB = SSB/(k-l)
MSW = SSW/(N-k)
F = MSB/MSW
153
-------
1790g
Example 3 (continued)
where,
k = number of treatment technologies
n = number of data 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, J2= 2850.49, T2 = 209.96
T = 1513.21
SSB =1 + I = 9.52
4 7 j 11
[209 96
~T~
MSB = 9.52/1 = 9.52
MSW = 14.88/9 =1.65
F = 9.52/1.65 = 5.77
ANOVA Table
Degrees of
Source freedom
Between (B) 1
Within(W) 9
SS MS F
9.53 9.53 5.77
14.89 1.65
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.
154
-------
A.2 Variability Factor
-£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 show that the treatment residual concentrations are
155
-------
distributed approximately lognormally. Therefore, the lognormal model
has been used routinely 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
follows:
C99 = Exp (M + 2.33a) (2)
Mean = Exp (M + .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 - .5a2). (4)
For residuals with concentrations that are not all below the
detection limit, the 99th percentile and the mean can be estimated from
the actual analytical data and, accordingly, the variability factor (VF)
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can be estimated using equation (1). For residuals with concentrations
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)J / 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.
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APPENDIX B - Analytical Methods and QA/QC
From Onsite Engineering Report for Envirite Corporation
158
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APPENDIX B
The analytical methods used for analysis of the regulated
constituents identified in Section 5 are listed in Table B-l. SW-846
methods (EPA's Test Methods for Evaluating Solid Waste; Physical/Chemical
Methods, SW-846, Second Edition, July 1982) are used in most cases for
determining total constituent concentrations. Leachate concentrations
were determined using the Toxicity Characteristic Leaching Procedure
(TCLP), published in 51 FR 1750, January 14, 1986.
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1833g
Table B-l Analytical Methods for Regulated Constituents
Regulated constituent
Extraction method
TOTAL COMPOSITION
Chromium Specified in analytical method
Copper
Lead
Nickel
TCLP EXTRACT
Chromium
Lead
Specified in analytical method
Specified in analytical method
Specified in analytical method
Analytical method
Chromium (atomic absorption,
direct aspiration method)
Copper (atomic absorption,
direct aspiration method)
Lead (atomic absorption,
direct aspiration method)
Nickel (atomic absorption,
direct aspiration method)
Toxicity Characteristic Leaching
Procedure (TCLP)
Toxicity Characteristic Leaching
Procedure (TCLP)
Reference
7190
220.1
7420
7520
51 FR 1750 2
51 FR 1750 2
References:
1. Environmental Protection Agency. 1982. Test Methods for Evaluating Solid Waste. Second Edition. U.S. EPA. Office of Solid Waste.
July 1982.
2. Federal Register. 1986. Hazardous Waste Management Systems; Land Disposal Restrictions; Proposed Rule; Appendix I to Part 260 -
Toxicity Leaching Procedure (TCLP). Vol. 51, No. 9. January 14. 1986. pp. 1750-1755.
3. Environmental Protection Agency. 1983. Methods for Chemical Analysis of Water and Wastes. U.S. EPA Office of Solid Waste.
EPA-600/4-79-020.
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APPENDIX C - Analytical Method for Determining
Thermal Conductivity of a Waste
161
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APPENDIX C
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
that 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 in a cell consisting of a top and
bottom of a Pyrex 7740 and a containment ring of marinite. The sample is
2 inches in diameter and .5 inch thick. Thermocouples are not placed in
the sample; rather, the temperatures measured in the Pyrex are
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GUARD
GRADIENT.
STACK
GRADIENT
THERMOCOUPLE
CLAMP
UPPER STACK
HEATER
1
TOP REFERENCE
SAMPLE
1
TESTAMPLE
J
BOTTOM
REFERENCE
SAMPLE
1
LOWER STACK
HEATER
1
LIQUID 'COOLED
HEAT SINK
1
HEAT FLOW
DIRECTION
Figure 1.
SCHEMATIC DIAGRAM OF THE COMPARATIVE METHOD
UPPER
GUARD
HEATER
LOWER
GUARD
HEATER
Reference: VSR-1
163
January 1988
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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.
The stack is clamped with a reproducible load to ensure 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 tube 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. = A^ (dT/dxh
in top top
and the heat out of the sample is given by
out = A (dT/dx)
bottom bottom
where:
A = thermal conductivity
dT/dx = temperature gradient
164
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and top refers to the upper reference, while bottom refers to the lower
reference. If the heat was confined to flow down the stack, then 0
in
and Q would be equal. If Q and Q are in reasonable
out in out
agreement, the average heat flow is calculated from
Q ' (Qin + "out'/2'
The sample thermal conductivity is then found from
A . = Q/(dT/dx) .
sample sample
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