&EPA
United States
Environmental Protection
Agency
Research and
Development
(RD681)
EPA/540/A5-89/011
May 1991
Chemfix Technologies, Inc.
Solidification/Stabilization
Process
Applications Analysis Report
SUPERFUND INNOVATIVE
TECHNOLOGY EVALUATION
:~*s^ I
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EPA/540/A5-89/011
May 1991
Chemfix Technologies, Inc.
Solidification/Stabilization Process
Applications Analysis Report
Risk Reduction Engineering Laboratory
Office of Research and Development
U.S. Environmental Protection Agency
Cincinnati, Ohio 45268
Printed on Recycled Paper
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Notice
The information in this document has been funded by the U.S. Environmental
Protection Agency under Contract No. 68-03-3484 and the Superfund Innovative
Technology Evaluation (SITE) program. It has been subjected to the Agency's peer
review and administrative review, and it has been approved for publication as a U.S. EPA
document Mention of trade names or commercial products does not constitute an
endorsement or recommendation for use.
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Foreword
The Superfund Innovative Technology Evaluation (SITE) program is a joint effort
between EPA's Office of Research and Development (ORD) and Office of Solid Waste and
Emergency Response (OSWER). The purpose of the program is to assist the development of
hazardous waste treatment technologies necessary to meet new, more permanent cleanup
standards. The SITE program includes technology demonstrations to provide engineering and
cost data on selected technologies.
A field demonstration was conducted under the SITE program to evaluate the Chemfix
Technologies, Inc. solidification/stabilization technology. The technology demonstration took
place at a Superfund site in Clackamas County, Oregon. The demonstration provided informa-
tion on the performance and cost of the technology for use in assessing its applicability to this
as well as other uncontrolled hazardous waste sites. The demonstration is documented in two
reports: (1) a Technology Evaluation Report that describes the field activities and laboratory
results; and (2) this Applications Analysis Report, which interprets the data and discusses the
potential applicability of the technology.
A limited number of copies of this report will be available at no charge from EPA's Center
for Environmental Research Information, 26 West Martin Luther King Drive, Cincinnati, Ohio
45268. Requests should include the EPA document number found on the report's front cover.
When the limited supply is exhausted, additional copies can be purchased from the National
Technical Information Service, Ravensworth Bldg., Springfield, Virginia, 22161, (703)487-
4600. Reference copies will be available at EPA libraries in the Hazardous Waste Collection.
Call the SITE Clearinghouse hotline at 1-800-424-9346 or 382-3000 in Washington, D.C., to
inquire about the availability of other reports.
E. Timothy Oppelt,
Risk Reduction Engineering Laboratory
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Abstract
In support of the U.S. Environmental Protection Agency's (EPA) Superfund Innovative
Technology Evaluation (SITE) Program, this report evaluates the Chemfix Technologies,
Inc. (Chemfix), solidification/stabilization technology for on-site treatment of hazardous
waste. The Chemfix technology mixes and chemically treats waste material with proprietary
additives and waterinapatentedpugmill to formamorestablematerial. This reportevaluates
treatment efficiency and economic data from the SITE demonstration of the Chemfix
technology and other past applications.
The Chemfix demonstration was conducted at the Portable Equipment Salvage Com-
pany (PESQ site in Clackamas County, Oregon, in March 1989. The PESC site was a
transformer and metal salvage facility. Activities at the site left the soil contaminated with
polychlorinated biphenyl (PCBs), lead, copper, and other metals. Four on-site areas that
differedin soil type andcontaminantconcentrations were selected to test theChemfix process
on a range of feed materials. Approximately 7 to 8 cubic yards of contaminated soil were
excavated from each area and treated. Extensive waste material sampling and analysis were
performed before and after treatment so that physical, chemical, and leaching properties
could be compared.
According to results from the Toxicity Characteristics Leaching Procedure (TCLP), the
Chemfix technology is capable of decreasing the mobility of cadmium, copper, chromium,
lead, nickel, and zinc. Lead and copper removals greater than 95 percent were achieved.
Available data do not allow conclusions to be drawn regarding the effectiveness of the
Chemfix technology in stabilizing organic contaminants or in dechlorinating PCBs. Dem-
onstration data suggest partial dechlorination of PCBs; however, no byproducts of complete
dechlorination were found.
The physical stability and durability of the treated waste were demonstrated using
unconfined compressive strength (UCS), wet/dry, and freeze/thaw physical testing. TheUCS
of the treated waste satisfied the EPA guidance level of 50 pounds per square inch (psi) for
placementinalandfill.Less than 1-percent weightless after 12cycles of wet/dry and freeze/
thaw weathering tests indicates treated waste durability in an exposed environment Treat-
ment results in a volume increase of 20 to 50 percent in the excavated raw waste.
Suitable wastes for Chemfix technology treatment include metals-containing industrial
and municipal wastes and soils contaminated with metals. Economic data indicate that the
cost of the treatment process is approximately $73 per ton of waste treated, excluding the
costs of waste excavation, curing, and storage and final placement or disposal of the treated
waste. The total cost of treatment depends on the rate of processing, the need to pretreat
wastes, and costs associated with placement or disposal of treated waste.
IV
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Contents
Notice ii
Foreword iii
Abstract iv
Abbreviations vii
Conversion of U.S. Customary Units to Metric Units ix
Acknowledgments x
1 Executive Summary 1
Overview of the Site Demonstration 1
Results from the Site Demonstration 1
Leaching Tests 1
Physical Tests 1
PCB Dechlorination '".'.".".2
Results from Past Applications 2
Conclusions 2
2 Introduction 3
Purpose, History, and Goals of the Site Program 3
Documentation of Site Demonstration Results 3
Purpose of the Applications Analysis Report 3
Chemfix Process Description 4
Process Chemistry 4
Principal Treatment Operations 4
Innovative Features of the Chemfix Process 6
Chemfix Process Limitations 6
3 Technology Applications Analysis 7
Technology Evaluation 7
Effectiveness of the Chemfix Solidification/Stabilization Process 7
Site Characteristics 8
Materials Handling 8
Regulatory Requirements 9
Comprehensive Environmental Response, Compensation and Liability Act 9
Resource Conservation and Recovery Act 10
Toxic Substances Control Act 10
Occupational Safety and Health Act 10
4 Economic Analysis 11
Site-Specific Factors Affecting Cost 11
Basjs of Economic Analysis 11
Waste Treatment Costs by Category 11
Site Preparation Costs „ 11
Permitting and Regulatory Costs 'll
Capital Equipment Costs „ 12
Equipment Installation/Startup 12
Equipment Transport 13
Labor Costs 13
Supply and Consumable Costs 13
Utility and Miscellaneous Costs 13
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Effluent Treatment and Decontamination Costs 13
Analytical Costs •• 14
Equipment Repair and Replacement Costs 14
Mobilization/Demobilization Costs 14
Residuals and Waste Shipping, Handling, and Transportation Costs 14
Potential Additional Costs 14
Summary of Economic Analysis 14
References 14
Appendices
A Key Contacts for the Site Demonstration 16
B Vendor's Claims for the Technology 17
C Site Demonstration Results > 20
D Past Applications of Chemfix Technology..,. 29
Tables
4-1. Chemfix Cost Model , 12
4-2. Estimated Costs of Chemfix Treatment Technology by Category ; 13
4-3. Potential Additional Costs for Solidification/Stabilization Processes 14
C-l. Summary of Demonstration Objectives, Test Methods, andResults 21
C-2. Analytical Procedures Used for the Site Demonstration 23
C-3. Mean Concentrations of Metals in Untreated and Treated Material from Site Demonstration 24
C-4. Chemical and Physical Test Results * 27
C-5. Summary of Chemfix Operating Conditions 28
D-l. EP Toxicity Test Data for Delisted Wastes Solidified and Stabilized
with the Chemfix Process 30
D-2. EP Toxicity Test Data for Industrial Wastes, Solidified and Stabilized
with the Chemfix Process during the 1970s (mg/L) ....30
D-3. Application of Standard Chemfix Treatment Technology to Waste Spiked
with Inorganic Contaminants ....31
D-4. Application of Chemfix Treatment Technology with Assorted Additives
to Spiked Electroplating Waste 31
D-5. Results of Application of Chemfix Process to S ARM 32
D-6. Summary of Results from Treatability Study Involving Contaminated Soil from Superfund Site.... 32
D-7. EP Toxicity Test Data from Municipal Wastes Stabilized with the Chemfix Process 32
Figures
2-1. Chemfix Technologies, Inc., high solids treatment system 5
C-l. Summary of extraction data for raw waste TCLP and MEP data from all areas 26
C-2. Summary of extraction data for treated waste TCLP and MEP data from all areas 26
VI
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Abbreviations
ANS 16.1 American Nuclear Society Leaching Procedure
ARARs applicable or relevant and appropriate requirements
BET Batch Extraction Test
BDAT best demonstrated available technology
C Celsius
CAA Clean Air Act
CERCLA Comprehensive Environmental Response, Compensation, and Liability Act
cfin cubic feet per minute
CFR Code of Federal Regulations
cm centimeter
DOT Department of Transportation
Eh oxidation/reduction potential
EP Extraction Procedure Toxicity Test
EPA Environmental Protection Agency
F Fahrenheit
FR Federal Register
ft foot (feet)
gal gallon
gpd gallons per day
hr hour(s)
HSWA Hazardous and Solid Waste Amendments to RCRA
kg kilogram(s)
L liter
lb(s) pound(s)
LDR Land Disposal Restrictions
mg milligram(s)
mg/kg milligram per kilogram
mg/L milligram per Liter
mil thousandth of an inch
mm millimeter(s)
mo month
mv millivolt(s)
NA not analyzed
NC not calculated
VII
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NCP National Contingency Plan
ND not detected
ORD Office of Research and Development
OSHA Occupational Safety and Health Administration
OSWER Office of Solid Waste and Emergency Response
PCB polychlorinatedbiphenyl
PESC Portable Equipment Salvage Company
pH negative logarithm of the hydrogen ion activity
ppm parts per million
PRC PRC Environmental Management, Inc.
psi pounds per square inch
RCRA Resource Conservation and Recovery Act
SARA Superfund Amendments and Reauthorization Act
sec second
SITE Superfund Innovative Technology Evaluation
SVOC semivolatile organic compound
SWDA Solid Waste Disposal Act
TCLP Toxicity Characteristics Leaching Procedure
TSCA Toxic Substances Control Act
jig micrograms
Hg/L micrograms per liter
UCS unconfined compressive strength
VOC volatile organic compound
wk week
wt weight
yd yard
yr year
viii
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Conversion of U.S. Customary Units to Metric Units
Length
inches x
inches x
feet x
Volume
gallons x
cubic yards x
Weight
pounds x
short tons x
Temperature
5/9 x
Note: 1000 liters
1000 kilograms
2.54
0.0254
0.3048
3.785
0.7646
0.4536
0.9072
(degrees Fahrenheit - 32) =
= 1 cubic meter
= 1 metric ton
centimeters
meters
meters
liters
cubic meters
kilograms
metric tons
degrees Celsius
ix
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Acknowledgments
This document was prepared under the direction of Ed Earth, U.S. EPA SITE project
manager, Risk Reduction Engineering Laboratory, Cincinnati, Ohio. Contributors to and
reviewers of this report were Jim Cummings of U.S. EPA, Office of Solid Waste and
Emergency Response, Washington, DC; Gordon Evans, and Guy Simes of U.S. EPA Risk
Reduction Engineering Laboratory, Cincinnati, Ohio; John Sainsbury of U.S. EPA Region
10; and Phillip Baldwin of Chemfix Technologies, Inc. Additional technical reviewers were
Mr. Peter Hannack, Dr. Pierre C6te, and Dr. R. Soundarajan.
This report was prepared for the EPA's Superfund Innovative Technology Evaluation
(SITE) program by Mark Evans, Nancy Willis, and Michael Keefe, and edited by Jon Mann
of PRC Environmental Management, Inc., under Contract No. 68-03-3484.
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Section 1
Executive Summary
The Chemfix Technologies, Inc. (Chemfix) solidifica-
tion/stabilization technology for high solids-content wastes
and soils was demonstrated and evaluated under the Super-
fund Innovative Technology Evaluation (SITE) program in
March 1989. The Chemfix technology is a patented process
for ex-situ solidification/stabilization of hazardous wastes
using proprietary additives such as soluble silicates and cal-
cium-containing reagents. One of the unique aspects is that
the process .is designed to treat large quantities of waste in a
short time because of high capacity equipment.
The U.S. Environmental Protection Agency (EPA) re-
viewed data from the SITE demonstration, commercial appli-
cations of the technology, and treatability studies conducted
under both a Small Business Innovative Research (SBIR)
project and the Superfund Analytical Reference Material
(SARM) program to draw conclusions regarding applications
of this technology at hazardous waste sites with contaminated
soils containing metals, semivolatile organics, and polychlori-
nated biphenyls (PCBs).
Overview of the Site Demonstration
The Chemfix waste solidification/stabilization technology
was demonstrated under the SITE program at the Portable
Equipment Salvage Company (PESC) site in Clackamas
County, Oregon. The PESC site was a transformer and metal
salvage facility from the 1960s until 1985. Its operations
involved scrapping and recycling power transformers contain-
ing PCBs. Activities at the site left the soil heavily contaminated
with lead, copper, and PCBs.
For the SITE demonstration, EPA selected four on-site
areas that differed in soil type and contaminant concentration
in order to test the Chemfix process on a range of feed
material characteristics. Approximately 7 to 8 cubic yards of
contaminated soil were excavated from each area. The con-
taminated soil was screened to remove particles greater than 1
inch in diameter. In general, Chemfix equipment cannot pro-
cess material greater than 1 inch in diameter.
Five Chemfix solidification/stabilization trials were con-
ducted: one calibration run with clean sand and one production
run with waste from each of the four designated areas. Each
run processed 4 to 6 cubic yards of material. Although the
design capacity of the Chemfix equipment used at the SITE
demonstration is 40 to 60 cubic yards per hour, the amount of
material treated was limited to minimize the quantity of waste
that required disposal after the demonstration. The small
quantities used for the demonstration may have affected the
performance of the equipment by significantly reducing the
time available to calibrate and adjust the process equipment.
Raw soil samples taken on the day of the demonstration
and treated soil samples taken immediately after processing
and curing were tested to provide comparisons of physical and
chemical characteristics of the wastes before and after treat-
ment EPA conducted leaching, physical, chemical, and PCB
dechlorination tests to meet the objectives of the SITE dem-
onstration.
Results from the Site Demonstration
The analyses conducted on the raw and treated wastes for
this demonstration may be grouped into three classes: leach-
ing tests, physical tests, and tests for PCB dechlorination. In
addition, air monitoring was conducted during the demon-
stration to determine whether PCBs were released to the air as
the technology was implemented. Results from the analysis
program are presented below.
Leaching Tests
• The Chemfix process treated batches of wastes that con-
tained highly variable amounts of contaminants. The con-
centration of lead and copper in the soils ranged from
11,000 to 140,000 and from 18,000 to 33,000 mg/kg,
respectively. In toxicity characteristic leaching procedure
(TCLP) extracts from the raw soil, lead ranged from 390 to
880 mg/L and copper ranged from 45 to 12 mg/L. The
mean concentrations of lead and copper in the TCLP
extract were reduced 95 to 99 percent by Chemfix solidifi-
cation/stabilization. These reductions are not corrected for
volume dilution by Chemfix reagents.
• Lead leachability indices for the treated material calcu-
lated from results of the ANS 16.1 test met the Nuclear
Regulatory Commission leachability standard by several
orders of magnitude.
• Multiple extraction procedure (MEP) analyses determined
the leaching properties of waste using the Resource Con-
servation and Recovery Act (RCRA) extraction procedure
(EP) followed by nine sequential extractions with acidified
distilled water. The mean lead concentration in the first
extract exceeded the EP toxicity standard of 5 mg/L.
Extractions two through ten had much lower mean con-
centrations of lead, although the mean concentration in the
latter extractions showed an upward trend.
Physical Tests
• The unconfined compressive strength (UCS) of the treated
material was stable after 14 days of curing.
• The results of UCS tests on samples taken throughout the
treatment process showed that the UCS varied consider-
ably between 250 to 300 psi in the first 2 to 4 minutes of
1
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treatment. As treatment progressed, the UCS decreased to
an average of approximately 90 psi. It could not be deter-
mined if this variation at the early stage of the treatment
process was caused by variations in the raw soil, sampling,
or testing methods.
• Results from both the wet/dry weathering tests and the
freeze/thaw weathering tests indicated that the tested
samples had no significant weight loss after 12 cycles (less
than 1 percent) compared to the control samples.
• A volume increase of 20 to 50 percent in the excavatedraw
waste resulted from the addition of Chemfix reagents.
PCS Dechlorination
• PCB extraction data showed evidence of partial dechlori-
nation. The analyses indicated that heavily chlorinated
PCB molecules may lose one or more chlorine atoms
during treatment. A more detailed analysis of the treated
waste failed to reveal products of complete dechlorination.
It is not clear to what extent the Chemfix process contrib-
uted to PCB dechlorination. Therefore, no conclusions can
be drawn regarding the effectiveness of the process in
dechlorinating PCBs.
• Air analyses showed that PCB concentrations in the air
during treatment were not significantly different from
concentrations in the air before treatment began. In addi-
tion, there was no difference in the concentrations of PCB
upwind and downwind of the treatment operations.
Results from Past Applications
The Chemfix process has been applied to industrial wastes,
spiked electroplating waste, Superfund wastes, and municipal
waste. Chemfix treated 150 million gallons of dissolved air
flotation sludge (K048) contaminated with lead and 6.8 mil-
lion gallons of electroplating wastewater treatment sludge
(F006) in 1985 and 1986, respectively. Based on results from
multiple extraction procedures (MEP) testing, these wastes
were delisted from EPA's list of hazardous waste after solidi-
fication/stabilization by Chemfix. Treatability studies of other
industrial wastes indicated that the Chemfix process effectively
reduced leaching of arsenic, chromium, cadmium, nickel, and
lead to acceptable levels.
In 1987, Chemfix completed work on the Small Business
Innovative Research (SBIR) project for EPA. For this study,
Chemfix spiked electroplating waste (F006) with metals and
solidified/stabilized the waste. The Chemfix process caused a
94 percent reduction of lead in the TCLP extract (from an
original concentration of approximately 40 mg/L). Mobility
of arsenic, barium, selenium, silver and vanadium were unaf-
fected by the Chemfix treatment, and the mobility of anti-
mony and mercury increased. The effect of treatment additives
was also evaluated in the SBIR.
Prior to the SITE demonstration, the Chemfix process
was tested on Superfund Analytical Reference Material
(SARM), a synthetic soil. Concentrations of cadmium, cop-
per, chromium, nickel, lead, and zinc in TCLP extracts from
untreated SARM were approximately 28,192,7,21,33, and
525 mg/L, respectively. The concentrations of these metals in
the TCLP extract from Chemfix-treated material were re-
duced 99 percent.
The Chemfix process has been used to solidify municipal
sewage sludge. Treated sludge has been used as daily cover
and final capping material for sanitary landfills.
Conclusions
The following conclusions regarding applications of the
Chemfix technology for ex-situ stabilization of waste were
drawn from SITE demonstration data and other available data:
• Based on TCLP results, the Chemfix technology is capable
of decreasing the mobility of cadmium, copper, chro-
mium, lead, nickel, and zinc.
• Based on TCLP tests from previous treatability studies,
antimony, barium, mercury, selenium, silver, thallium,
and vanadium are more difficult for the Chemfix process
to immobilize.
• Treatment data for arsenic were ambiguous: the extent to
which arsenic was fixed by the Chemfix process varied
between applications. Therefore, it is difficult to draw
specific conclusions from arsenic data.
• The available data do not allow conclusions regarding the
effectiveness of the Chemfix technology in stabilizing
organic contaminants or in dechlorinating PCBs. SITE
demonstration data suggest partial dechlorination of PCBs;
however, byproducts of complete dechlorination were not
found.
• Waste material must be screened or reduced in size to less
than 1 inch in diameter before processing with Chemfix
equipment.
• Physical properties of Chemfix-treated material indicate
durability in an exposed environment.
• Highly variable raw waste feed characteristics can result in
a treated product that is variable in quality.
• The cost of the treatment process is $73 per ton of raw
waste treated. This estimate is based on cost information
supplied by Chemfix and the materials-handling costs
incurred during the SITE demonstration. This estimate
does not include the cost of waste excavation, curing,
storage, and final placement or disposal of the product
The total cost of treatment depends on the rate of process-
ing, the need to pretreat wastes to remove other contami-
nants, and costs associated with placement or disposal of
the treated waste.
• The total volume increase resulting from treatment with
Chemfix reagents is between 20 and 50 percent of the
excavated raw waste.
The Chemfix solidification/stabilization technology is an
economical remedial action alternative for decreasing mobil-
ity of lead, copper, zinc, and other metals in contaminated
soils. Site-specific factors such as contaminant concentration,
presence of organic constituents, metal speciation, soil condi-
tions, ground-water conditions, and possible pretreatment needs
make site-specific treatability studies necessary before appli-
cation of the technology at a particular hazardous waste site.
Other leaching tests may be necessary to determine the long
term effectiveness of solidification/stabilization processes.
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Section 2
Introduction
This section describes the SITE program, discusses the
purpose of the Applications Analysis Report, and describes
the Chemfix technology. A list of key personnel who can be
contacted for additional information is provided in
Appendix A.
Purpose, History, and Goals of the Site
Program
The Superfund Amendments and Reauthorization Act of
1986 (SARA) directed the U.S. Environmental Protection
Agency (EPA) to establish an "Alternative or Innovative
Treatment Technology Research and Demonstration Program."
In response, United States EPA's Office of Solid Waste and
Emergency Response (OSWER) and Office of Research and
Development (ORD) established a formal program called the
Superfund Innovative Technology Evaluation (SITE) Pro-
gram. The SITE Program accelerates development and use of
innovative cleanup technologies at hazardous waste sites across
the country.
The SITE Program consists of the following:
• Demonstration Program
• Emerging Technologies Program
• Measurement and Monitoring Technologies Devel-
opment Program
• Innovative Technologies Program
• Technology Transfer Program
This document was produced as part of the SITE Demon-
stration Program. The objective of the SITE Demonstration
Program is to develop reliable engineering performance and
cost data on innovative technologies so that potential users
can evaluate each technology's applicability to a specific site
as compared to other alternatives. Demonstrations are con-
ducted at hazardous waste sites (usually Superfund sites) or
under conditions that closely simulate actual wastes and con-
ditions. This assures the usefulness and reliability of infor-
mation collected.
Data collected during a demonstration are used to assess
the performance of the technology, the potential need for pre-
and post-treatment processing of the waste, applicable types
of waste and media, potential operating problems, and ap-
proximate capital and operating costs. Demonstration data can
also provide insight into long-term operating and maintenance
cosjs and long-term risks.
Technologies are selected for the SITE Demonstration
Program through annual requests for proposal (RFPs). Pro-
posals are reviewed by OSWER and ORD staff to determine
the technologies with the most promise for use at hazardous
waste sites. Technologies are selected following interviews
with the developers. To be eligible, technologies must be at
the pilot or full-scale stage, must be innovative, and must offer
some advantage over existing technologies. Mobile technolo-
gies are of particular interest Cooperative agreements be-
tween EPA and the developer set forth responsibilities for
conducting the demonstration and evaluating the technology.
The developer is responsible for demonstrating the technol-
ogy at the selected site and is expected to pay the costs to
transport, operate, and remove the equipment. EPA is re-
sponsible for project planning, sampling and analysis, quality
assurance and quality control, preparing reports, and dissemi-
nating information.
Documentation of Site Demonstration Results
The results of the Chemfix SITE demonstration are incor-
porated in two documents: the Technology Evaluation Report
and the Applications Analysis Report. The Technology
Evaluation Report provides a comprehensive description of
the demonstration and its results. It is intended for engineers
making a detailed evaluation of the technology for a specific
site and waste situation. These technical evaluators seek to
understand in detail the performance of the technology during
the demonstration and the advantages and risks of the technol-
ogy for the given application. This information will be used to
produce conceptual designs in sufficient detail to make pre-
liminary cost estimates for the demonstrated technology.
The Applications Analysis Report is intended for deci-
sion-makers responsible for implementing specific remedial
actions. The basic use of the Applications Analysis Report is
to assist in determining whether the specific technology should
be considered further as an option for a particular cleanup
situation. The report discusses advantages, disadvantages, and
limitations of the technology. Costs of the technology for
different applications are estimated based on available data
for pilot- and full-scale applications. The report discusses
factors, such as site and waste characteristics, that have a
major impact on cost and performance. If a candidate technol-
ogy appears to meet the needs of site engineers, a more
thorough analysis can be conducted. This analysis will be
based on the Technology Evaluation Report, the Applications
Analysis Report, and information from remedial investiga-
tions for the specific site.
Purpose of the Applications Analysis Report
To encourage general use of demonstrated technologies,
EPA provides information on the applicability of each tech-
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nology to certain sites and wastes, other than those already
tested, and studies the costs of these applications. Available
information is presented in the Applications Analysis Report.
This report synthesizes available information on a technology
and draws reasonable conclusions about its broad-range ap-
plicability. The Applications Analysis Report is very useful to
those considering a technology for Superfund cleanups; it
represents a critical step in the development and commercial-
ization of a treatment technology.
l
Each SITE demonstration will evaluate the performance
of a technology in treating a particular waste found at the
demonstration site. To obtain data with broad applications,
attempts will be made to select waste frequently found at other
Superfund sites. In many cases, however, waste at other sites
will differ in some way from the waste tested. Thus the
successful demonstration of a technology at one site does not
ensure that it will work equally well at other sites. Data
obtained from the demonstration may have to be extrapolated
to estimate the total operating range over which the technol-
ogy performs satisfactorily. This extrapolation should be based
upon both demonstration data and other information available
about the technology.
The amount of data available for evaluation of an inno-
vative technology varies widely. Data may be limited to
laboratory tests on synthetic wastes or may include performance
data on actual wastes treated with pilot- or full-scale treatment
systems. In addition, there are limits to conclusions thatcan
be drawn from a single field demonstration. A successful field
demonstration does not necessarily ensure that a technology
will be widely applicable or will be fully developed on a
commercial scale.
Chemfix Process Description
Solidification/stabilization technologies are employed to
decrease the rate at which chemical contaminants migrate into
the environment. This is accomplished by reducing or elimi-
nating contaminant leaching through a chemical process in
which pollutants are chemically bound or entrapped, or both,
in a solid matrix. This generally improves handling and physical
characteristics of hazardous wastes.
Solidification of waste material in a solid matrix is a
physical process that reduces the surface area available for
leaching. Stabilization implies a chemical process that causes
contaminants to be less mobile. Chemical solidification/stabi-
lization of hazardous wastes is typically achieved by mixing
the waste with cement, lime, kiln dust, flyash, or some other
material. The performance of waste-solidifying formulations
varies widely according to the composition of the mixture and
the contaminants of concern.
The Chemfix process is a technology with patented ad-
ditives originally formulated in the early 1970s. Chemfix also
holds a patent on specific process mixing equipment used to
solidify/stabilize wastes. Chemfix has applied the process and
formulations to a wide variety of wastes. Originally, the
process was used primarily to solidify/stabilize liquid wastes
and semi-liquid wastes into a soil-like material suitable for
transport or land disposal. After the passage of the Resource
Conservation and Recovery Act (RCRA) in 1976 and the
regulations implementing RCRA, th$ process was used to
limit contaminant mobility in hazardous wastes.
The Chemfix solidification/stabilization process can treat
solids, liquids, and sludges ranging between 8 and 75 percent
solids by weight. Water and two reagents developed by
Chemfix (CHEMSET1-20 dry reagent and CHEMSET C-220
liquid reagent) are added to waste material to achieve solidi-
fication/stabilization. The Chemfix technology processes waste
in what Chemfix terms a continuous process. The following
process description is based primarily on information pro-
vided by Chemfix.
Process Chemistry
The Chemfix process is based on use of a proprietary
family of polysilicates (CHEMSET C-220) and dry calcium-
containing reagents (CHEMSET 1-20). The two-phase inor-
ganic chemical system reacts with polyvalent metal ions in the
waste, certain other waste components, and itself to produce a
chemically and physically stable solid matrix (Chemfix, 1987).
The matrix-forming chemistry is assisted as needed by reaction-
promoting additives. The combination and proportions of
reagents are optimized for the waste stream (solid, liquid, or
sludge) requiring treatment. Chemfix designed the process to
reduce the mobility and toxicity of metals as well as of base,
neutral, and acid (BNA) extractable organics with high mo-
lecular weights.
According to Chemfix, the solidified matrix is based on
tetrahedrally coordinated silicon atoms alternating with oxy-
gen atoms along the backbone of a linear chain. The charged
side group (in this case, oxygen) reacts with polyvalent metal
ions, resulting in strong ionic bonding between adjacent chains.
This bonding forms a cross-linked, three-dimensional polymer
matrix that has a high stability, a high melting point, and a
rigid, friable structure (Salas, 1980).
Three classes of interactions occur during the solidifica-
tion/stabilization process. First are the very rapid reactions
among CHEMSET polysilicates, certain reaction promoters,
and metal ions. These produce insoluble metal silicates that
cannot be resolubilized and are resistant to breakdown under
severe environmental conditions. The second class of inter-
actions occurs between polysilicate molecules and reactive
components within the dry reagent to produce a gel structure.
The gel holds ions in place by chemical and physical bonding
mechanisms. Other waste components such as oils are also
trapped in the structure and thereby immobilized. The third
class of interactions occurs among die dry reagent, the waste,
and water (both free and contained) as the dry reagent under-
goes a series of hydrolysis, hydration, and neutralization
reactions (Chemfix, 1987).
Principal Treatment Operations
A typical Chemfix soil treatment system consists of a
feed hopper, a primary conveyor, a weigh feeder, a high-speed
shear process mixer (homogenizer), a dry reagent storage
tank, a liquid reagent storage tank, two alarm and control
panels, a high shear process mixer, and other associated
equipment (Figure 2-1). The various constituents of the treat-
ment system are connected both physically and electronically;
the actual arrangement of the equipment may vary with site
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Front End Loader
Hopper with
Even Feeder
Conveyor -*> | Weight Feeder
Water Supply (if
required)
Alarms and Control
Panel No. 2
Alarms and Control
Panel No. 1
Legend
Transmitter
] Controller
Chute to
Truck
Loading
Area
Figure 2-1.
Chemfix Technologies, Inc., high solids treatment system block process flow diagram.
conditions. The configuration used at the Portable Equipment
Salvage Company (PESC) site was designed to handle 40 to
75 cubic yards of material per hour. The system used at the
PESC site was operated by two people, one person to operate
each alarm and control panel.
The Chemfix solidification/stabilization process is best
described by tracing the flow of soil through the system. The
process is divided into two phases: (1) waste preparation
(operations before the addition of Chemfix reagents) and (2)
waste treatment (all subsequent operations).
The first step in the waste preparation phase is the trans-
fer of soil from the soil storage area to the soil feed hopper,
which has a 15- to 20-cubic yard capacity. Feed material is
transferred by the variable speed primary conveyor to the
weigh feeder. The weigh feeder continuously meters con-
taminated material by weight into a high-speed shear process
mixer (homogenizer). The weigh feeder, which can deliver up
to 150,000 pounds per hour of waste material, electronically
regulates the amount of water added to the homogenizer. The
water flow rate depends on the weight of feed material entering
the homogenizer. The ratio of added water to feed material
can be set by adjusting the flow controller to obtain the
optimum soil-to-water ratio by weight. The speed of the
homogenizer is controlled from the alarm and control panel.
The second phase of the process, waste treatment, begins
as the soil-water mixture is transferred from the homogenizer
to the high shear process mixer. The dry and liquid reagents
are added to the process mixer, which uses a Chemfix-de-
signed pug mill to blend the ingredients. The dry reagent feeds
into the process mixer through a dry reagent feeder from the
storage silo. The liquid reagent is pumped from the storage
tank to the pug mill. The feed rates for dry and liquid reagents
are regulated by the amount of material fed to the homog-
enizer, which transmits an electronic weight signal to the
controllers of the dry reagent feed auger and the liquid reagent
feed pump. The reagents, soil, and water remain in the process
mixer until all the ingredients are blended into a pasty mix-
ture. The mixture moves from the receiving end of the process
mixer to the discharge chute as mixing occurs. The final
product is then discharged from the process mixer into a
storage bin and transported to a designated area for curing.
When sludges or liquid wastes are treated, the Chemfix
equipment must be modified. A typical, mobile, sludge treat-
ment system has a sludge tank, a magnetic flow meter, a
sludge supply pump, and two product-transfer pumps instead
of the feed hopper, conveyor, weight feeder, and homog-
enizer.
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Innovative Features of the Chemfix Process
The Chemfix treatment system is a mobile, self-con-
tained, continuous processing unit mounted on a flatbed trailer.
The innovative features of the turn-key system are the propri-
etary reagents and the high capacity pug mill mixer patented
by Chemfix. '
Chemfix Process Limitations
The Chemfix process has been used to treat a variety of
wastes, including contaminated soils, mine tailings, municipal
and industrial sludges, and petrochemical wastes. However,
the Chemfix process has limitations. It is generally not appli-
cable, without pretreatment, to wastes with the following
characteristics:
• Water content greater than 95 percent or less than 25
percent
• Oil and grease concentrations greater than 15 percent
• Waste feed material greater than 1 inch in diameter
• pH less than 2 or greater than 12
The Chemfix process requires enough space to accom-
modate all its treatment equipment. For example, for the SITE
demonstration, Chemfix required a 25 by 40-foot, curbed,
concrete pad for the processing unit and a 50 by 150-foot,
graded, gravel-covered area for loading and parking. Additional
space is required to store treated material 'during curing and
prior to final disposal.
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Section 3
Technology Applications Analysis
This section addresses the applicability of the Chemfix
solidification/stabilization process to hazardous waste sites.
Evaluations herein are based primarily on the results of the
SITE demonstrations, which are presented in detail in the
Technology Evaluation Report. This section also draws upon
data from treatability studies conducted as part of the Small
Business Innovative Research (SBIR) and Superfund Analyti-
cal Reference Material (SARM) projects, as well as informa-
tion supplied by Chemfix on several industrial projects using
the technology. Developer's claims regarding the applicabil-
ity and performance of the Chemfix technology are included
in Appendix B.
The successful application of a hazardous waste treatment
technology can be judged by the ability of the technology to
satisfy applicable or relevant and appropriate requirements
(ARARs). The effectiveness of the technology and the regula-
tory requirements are addressed below.
Technology Evaluation
A summary of SITE demonstration information, includ-
ing site characteristics, waste characteristics, and a review of
the Chemfix system's performance, is presented in Appendix
C. Past applications are presented in Appendix D.
The successful application of solidification/stabilization
treatment technology depends on at least three criteria: (1) the
chemistry of the wastes must match the performance range of
the technology; (2) the physical characteristics of the wastes
must meet the materials handling capability of the technology;
and (3) the site must be able to support the necessary equip-
ment, utilities, and supplies. In addition, the product must
meet disposal requirements established by law and regulation.
Effectiveness Of The Chemfix Solidification/
Stabilization Process
An important requirement for successful application of
the Chemffai technology is compatibility between the chemistry
of the treatment process and the chemistry of the waste to be
processed. .The following subsections focus on groups of
contaminants that may be considered similar with respect to
the applicability of the Chemfix technology. Because of varia-
tions in results for different waste matrices and contaminants,
the technology's performance is difficult to predict without
some bench-scale testing. Treatability studies are recommended
before large-scale applications are considered.
Cadmium, Copper, Chromium, Lead, Nickel, and Zinc
Data from the SBIR project and a Superfund site showed
reductions of 94 to 99 percent in concentrations of lead,
copper, and zinc in the TCLP extract from treated waste. The
TCLP extract from untreated wastes ranged from 4 to 38 mg/
L lead, 23 to 176 mg/L copper, and 158 to 530 mg/L zinc. In
addition, the SBIR study, the SARM project, and a Superfund
site cleanup indicated that the Chemfix process achieved 99-
percent reductions in concentrations of cadmium, chromium,
and nickel in the TCLP extract from treated wastes.
Sixty-five percent of the samples of treated waste tested
from all areas of the PESC site satisfied the SITE demonstra-
tion standards of 0.51 mg/L of lead in the TCLP extract (based
on electroplating waste). Seventy percent of the samples
tested satisfied the arbitrary soil demonstration standard of 5.0
mg/L of lead in the TCLP extract. Although a substantial
fraction of the samples did not meet the demonstration stan-
dards, the raw waste at the SITE demonstration contained
very high concentrations (up to 14 percent) of lead. It should
be mentioned that soils with lead concentrations at this level
should be considered for lead recovery operations. Lead con-
centrations in TCLP extract from treated waste were signifi-
cantly less (94 to 99 percent) than those from the untreated
waste.
Although treatment results indicate that lead teachability
is substantially decreased, the amphoteric nature of lead should
be considered in any Chemfix applications. Lead hydroxides
are insoluble between pH 8 and 10.5 but become very soluble
as the pH increases past 11. The potentially high alkalinity of
solidified/stabilized waste material suggests that, at very high
concentrations, lead may leach from the solid matrix. The
potential for lead leaching increases if metal hydroxides are
formed and (lie material is disposed of in an area with leachate
or ground water that is neutral or alkaline (for example, in a
disposal unit dedicated to metal-containing wastes). Chemfix
claims that metal silicates rather than metal hydroxides are
formed, thereby eliminating the potential problem of increased
solubility at high pH.
Arsenic, Antimony, Barium, Mercury, Selenium, Silver,
Thallium, and Vanadium
The effectiveness of the Chemfix technology for stabiliz-
ing arsenic depends on waste-specific chemistry. Data from
treatability tests and the SARM project suggest effective
solidification/stabilization of arsenic. However, the SBIR study
showed difficulties in stabilizing arsenic, antimony, barium,
mercury, selenium, silver, thallium, and vanadium. Although
-------
contaminant-specific additives may help solidify/stabilize
certain metals, site-specific bench- and pilot-scale analyses
are required before applying the Chemfix technology to wastes
contaminated with these metals.
Organic Pollutants
Although Chemfix claims limited success in reducing
concentrations of organic contaminants in treated waste ma-
terial, the SITE demonstration was unable to confirm such
reduction. Volatile organic compounds (VOCs) were not
present in significant concentrations in the untreated wastes at
the PESC site. Semivolatile organic compounds were found
only in low concentrations and the data do not show that
levels were reduced by the treatment process.
The Chemfix treatment process requires a significant
amount of mixing to incorporate reagents into wastes, which
may cause heat generation. Therefore, VOCs may be released
to the atmosphere during treatment If significant concentrations
of organic pollutants are present in the waste material, another
technology may be required to pretreat the waste in order to
eliminate organic contaminants.
One objective of the SITE demonstration was to deter-
mine the fate of polychlorinated biphenyls (PCBs) during the
treatment process. Careful analysis of the wastes before and
after treatment indicated no reduction in the total concentration
of PCBs. However, the data did show some evidence of partial
dechlorination of PCBs. It could not be determined whether
this was the result of aging, physical mixing, or chemical
reagents. The mobility of PCBs before and after treatment
could not be analyzed because PCBs did not leach from raw
wastes during the TCLP extraction procedure.
Matrix Effects
High concentrations of solid organic material in the waste
may interfere with the performance of cement-based solidifi-
cation/stabilization technologies. During the SITE demon-
stration, the Chemfix technology was applied to wastes with
moderate organic content (3 to 8 percent total organic content).
These concentrations did not appear to affect the ability of [the
process to stabilize inorganic contaminants in the waste mate-
rial. However, there is evidence that indicates certain chemi-
cals such as phenol at concentrations of 8 percent can decrease
the UCS of the material by as much as 96 percent (HWC,
1988). Therefore, the biggest concern of organic content in
waste treated by solidification/stabilization may be the effect
on the physical properties of treated waste. ;
Past industrial applications of the Chemfix process include
treatment of large quantities of dissolved air flotation sludge
(K048) in order to remove the waste from EPA's list of
hazardous wastes. This waste contains high concentrations of
organic material. However, data available from that Chemfix
application are insufficient to reach a conclusion regarding the
effect of organic material on the treatment process.
Water Content
In the past, the Chemfix technology was applied prima-
rily to liquid waste and sludge. One innovative feature of the
SITE demonstration for this technology was its application to
contaminated soil. Because the treatment process requires a
high water content, water must be added when applying the
technology to relatively dry soil.
At the SITE demonstration, several of the treatment runs
were performed on waste and reagent mixtures containing less
than IS percent water. The optimal water content for this
application of the Chemfix process was 25 percent. The
solidification/stabilization results of the SITE demonstration
may be improved with higher water content; however, in-
creasing water content, together with the Chemfix reagents,
may increase the volume expansion of the treated material.
Site Characteristics
Chemfix set up a full-scale, mobile unit on a 2-acre site
for the SITE demonstration. Restricted site size can limit the
quantity of material that can be prepared for treatment in
advance and the quantity of product that can be cured on-site.
Minimum requirements for a Chemfix treatment operation
with a capacity of 75 to 100 cubic yards per hour, including
equipment, decontamination facility, and health and safety
requirements, are as follows:
• A 25- by 40-foot concrete pad for the process unit. This
unit is delivered to the site on three 40-foot trailers and
must be assembled on-site.
• A 50- by 150-foot graded pad covered with gravel for
parking, loading, and general work.
• A decontamination facility for trucks and equipment
working in the contaminated zone.
• A decontamination facility for personnel working in the
contaminated zone.
• An area for storing raw waste from the time it is excavated
until it is processed. This area includes space for a pre-
treatment unit for screening or crushing if the waste con-
tains particles larger than 1 inch in diameter.
• A storage area for treated product while it cures if it is to
be cured on-site before final disposal. Chemfix's experi-
ence and results of the SITE demonstration indicate that
treated material requires 72 hours to cure. Therefore, the
storage area for the treated product should be sized for
several days of production.
Logistical support required for the Chemfix technology
includes a source of electricity (480-volt, 3-phase, 60-Hz
power supply at 200 Amps), process water at 60 psi, potable
water and sanitary facilities for workers, and a telephone line.
Materials Handling
Most Superfund sites contain some form of contaminated
soil; therefore, this discussion of materials handling focuses
on Chemfix operations required to treat high solids-content
wastes such as soil. Waste material must be excavated,
stockpiled, treated, partially cured, and land-disposed, at a
minimum. In addition, other operations may be required, such
as screening or grinding to reduce particle size, additional
mixing to increase the homogeneity of wastes and incorporate
reagents, and emissions control for volatile pollutants.
Particle Size
The Chemfix treatment process requires that raw waste
be comprised of particles no larger than 1 inch in diameter.
8
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Therefore, most soils containing debris must be screened
before treatment. Screening is relatively easy to accomplish
with dry soils; however, moist or sticky material is difficult to
screen. Moreover, at the SITE demonstration the screening
operation allowed objects such as long wires to enter and clog
treatment equipment.
Screening has the disadvantage of creating sidestream
waste (large particles) that are inappropriate for treatment
with the Chemfix process. At the SITE demonstration, such
material amounted to 40 percent of the soil excavated. One
option is to crush the material into smaller particles to make it
suitable for application of the Chemfix technology. Another
option is to use a different technology, such as soil washing or
extraction, for larger particles as a pretreatment operation.
The option selected for larger particles depends on the nature
and quantity of the wastes considered for treatment
Reagent Delivery and Mixing
Results from the SITE demonstration indicated that prod-
ucts of the Chemfix treatment process varied significantly in
chemical composition and physical strength. During some of
the test runs, waste visually appeared to be significantly
underdosed with reagent and water compared to the theoreti-
cal doses determined from preliminary sampling.
Variations in the composition of raw waste are partially
responsible for variability in the treated waste. If waste mate-
rial exhibits significant variability, an additional mixing step
should be considered as a pretreatment operation to improve
the consistency of the treated waste.
Emissions Control
Control technology for emissions from the Chemfix tech-
nology exists for waste materials similar to the PESC site
wastes. Applications involving wastes contaminated with
metals do not present a volatilization problem. Dust emissions
from soils containing a large fraction of fine particles are the
primary concern. Metals and semivolatile organics adsorbed
onto fine particles present an inhalation risk to workers. Dust
emissions are generally controlled with traditional dust sup-
pression techniques such as application of water or synthetic
materials to strengthen adhesion between soil particles.
If the Chemfix technology is used to treat wastes with
significant levels of volatile organic contaminants, especially
volatiles, additional controls (such as a negative-pressure air
system) may be necessary to prevent releases during excava-
tion, screening, and mixing phases of the treatment process.
The exothermic nature of the chemical stabilizing process
releases heat that accelerates emissions of volatile contami-
nants.
Disposal Requirements
After wastes are solidified/stabilized using the Chemfix
process, a volume of material larger than the original excavated
waste volume requires disposal. According to data from the
SITE demonstration, the treated product will be 20 to 50
percent greater in volume than the untreated waste. The
volume expansion ratio is a site-specific factor, however, and
these percentages represent only a single application.
The cost-effectiveness of the Chemfix process depends in
part on whether treated material may be disposed of as a
nonhazardous waste. If the waste originates only as a charac-
teristic waste, and if the treatment process renders it
nonhazardous by removing all hazardous characteristics, the
material may be disposed of as a solid waste subject only to
requirement1; for municipal and solid wastes defined by state
regulations. However, if the waste remains hazardous after
treatment, either because the waste remains a listed waste or is
derived from a listed waste, or the waste remains of regulatory
concern, it must be disposed of as a hazardous waste at a
RCRA Subtitle C facility. The cost of such disposal will
significantly increase the total cost of Chemfix treatment.
In addition to the treated material, other waste streams
must be considered. Large particles screened during the
treatment process and water used to decontaminate personnel
and equipment must be treated and disposed of. The decon-
tamination water may be a liquid hazardous waste subject to
treatment and disposal requirements different than those that
apply to solid waste.
Regulatory Requirements
This section discusses federal regulatory requirements for
solidification/stabilization technology and analyzes these re-
quirements in view of SITE demonstration results. State and
local regulatory requirements, which may be more stringent,
will also have to be addressed by users of the technology.
Comprehensive Environmental Response,
Compensation and Liability Act
The Comprehensive Environmental Response, Compen-
sation and Liability Act of 1980 (CERCLA) authorizes the
federal government to respond to releases or potential releases
of any hazardous substance into the environment as well as to
releases of pollutants or contaminants that may present an
imminent or significant danger to public health and welfare or
the environment.
SARA amended CERCLA and directed EPA to
• Use remedial alternatives that permanently and signifi-
cantly reduce the mobility, toxicity, or volume of hazard-
ous substances, pollutants, or contaminants;
* Select remedial actions that protect human health and the
environment, are cost-effective, and involve permanent
solutions and alternative treatment or resource recovery
technologies to the maximum extent possible; and
• Avoid off-site transport and disposal of untreated hazard-
ous substances or contaminated materials when practi-
cable treatment technologies exist (Section 121[b]).
As part of the requirements of CERCLA, EPA prepared
the National Contingency Plan (NCP) for hazardous substance
response. The NCP (codified in 40 CFR Part 300) delineates
the methods and criteria used to determine the appropriate
extent of removal and cleanup for hazardous waste contami-
nation. The NCP includes solidification as a possible, cost-
effective technology for remediation of contaminated soils
and sediments (Section 300.70). The preference under SARA
for permanent solutions that reduce mobility, toxicity, or
volume applies to use of solidification/stabilization technolo-
9
-------
gics at CERCLA sites. Although solidification/stabilization
technologies do not reduce waste volume and may not reduce
toxicity, significant reductions in mobility are achievable.
EPA is required to review any remedial action in which
hazardous substances, pollutants, or contaminants remain at
the site. A remedial action in which hazardous substances are
treated by solidification/stabilization and are disposed of at
the site may need to be reviewed by EPA every 5 years to
ensure continued protection of human health and the envi-
ronment.
Contaminated soil and debris are the primary types of
waste at most CERCLA sites. If the soil and debris contain
hazardous wastes subject to RCRA Land Disposal Restrictions
(LDRs), they may need to be treated to comply with LDR
treatment standards or a variance must be obtained from EPA.
Resource Conservation and Recovery Act
RCRA regulations define hazardous wastes and regulate
their transport, treatment, storage, and disposal. Wastes defined
as hazardous under RCRA include characteristic and listed
wastes.
Several RCRA requirements may apply to hazardous
waste treatment by solidification/stabilization and to the dis-
posal of treated product. RCRA requires that solidified/stabi-
lized waste considered for land disposal contain no free
liquids. The presence or absence of free liquids should be
demonstrated using the paint filter liquids test (EPA Method
9095). Wastes treated by the Chemfix process usually will not
contain free liquids.
In addition, according to EPA land disposal guidance^for
stabilized waste (EPA, 1986a), theUCS of solidified/stabilized
waste must equal or exceed 50 psi. Based on results from the
SITE demonstration and other applications, waste treated by
the Chemfix process contain no free liquids and have a UCS
greater than 50 psi.
If the waste treated is a listed waste, the treatment product
will be considered a listed waste unless RCRA delisting
requirements are met Delisting requires that a demonstration
be made that the waste material has been adequately solidified/
stabilized. A successful petition for delisting must clearly
demonstrate that the treated waste does not exhibit any haz-
ardous characteristics (such as corrosivity, igniteability, reac-
tivity, or EP toxicity). The multiple extraction procedure
(MEP) is one method for testing the leaching properties of
waste treated by Chemfix to demonstrate that the waste has
been adequately solidified/stabilized. EPA delisted 150 million
gallons of dissolved air flotation sludge and 6.8 million gallons
of electroplating wastewater treatment sludge following so-
lidification/stabilization by Chemfix.
For both CERCLA and RCRA corrective actions, treated
waste produced by the Chemfix process may be subject to
LDR requirements if it is hazardous and land disposed. Sev-
eral LDR compliance alternatives exist for disposing of the
treated waste if they are hazardous: (1) comply with the LDR
that is in effect; (2) comply with the LDRs by choosing one of
the LDR compliance alternatives (for example, treatability
variance, no migration petition); or (3) invoke an applicable,
relevant, and appropriate requirement (ARAR) waiver (this
option would only apply to on-site CERCLA disposal).
EPA established treatment standards for listed and char-
acteristic hazardous waste based on the Best Demonstrated
Available Technology (BOAT) determined for each waste.
Under RCRA, hazardous wastes are restricted from land
disposal unless established treatment standards have been
met The established treatment standards may be applicable to
waste treated by the Chemfix process if the waste treated is
similar to a specific listed or characteristic wastestream.
However, RCRA provides for & treatability variance under 40
CFR 268.44 in which alternate treatment standards may be
utilized. Because soil and debris at Superfund sites often do
not meet narrowly defined waste categories, EPA established
guidance on applying a treatability variance to the treatment
of soil and debris from Superfund sites (EPA, 1989)
Toxic Substances Control Act
Disposal of PCBs is regulated under Section 6(e) of the
Toxic Substances Control Act of 1976 (TSCA). PCB treatment
and disposal regulations are described in 40 CER Part 761.
Materials containing PCBs in concentrations between 50 and
500 parts per million (ppm) may either be disposed of in
TSCA-permitted landfills or destroyed by incineration at
TSCA-approved incinerators; at PCB concentrations greater
than 500 ppm, the material must be incinerated. Therefore,
soil with PCB concentrations of up to 500 ppm may be
suitable for solidification. Where state standards are more
stringent than federal standards, solidification may be unac-
ceptable as a pre-disposal remedy.
Occupational Safety and Health Act
Superfund remedial actions and RCRA corrective actions
must be performed in accordance with Occupational Safety
and Health Act (OSHA) requirements detailed in 29 CFR
Parts 1900 through 1926. State occupational safety and health
requirements must also be met and may be more stringent
than federal standards.
10
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Section 4
Economic Analysis
One goal of the SITE program is to develop reliable cost
data for unique and commercially available hazardous waste
treatment technologies. Cost data for the Chemfix technology
were obtained primarily from a model provided by Chemfix
that is summarized in Table 4-1. Other sources of cost infor-
mation include EPA experience, the SITE demonstration, and
cost information obtained from vendors of equipment related
to solidification/stabilization processes. Costs presented in
this analysis are order-of-magnitude estimates (-30 to +50
percent).
Site-Specific Factors Affecting Cost
Several factors affecting the cost of the Chemfix system
are highly site-specific. They are difficult to calculate without
accurate data from a site remedial investigation report Four
sources contribute to the uncertainty and variability of cost
estimates for the Chemfix technology: (1) the extent to which
the chemical and physical characteristics of the waste match
the optimum feed characteristics of the technology, (2) site
logistics, (3) waste disposal regulations and requirements, and
(4) amount of material on-site.
Basis of Economic Analysis
The cost analysis was based on a standard size Chemfix
processing unit capable of treating approximately 160 tons of
raw waste per day during an 8 hour day. The cost analysis
assumes that the total amount of material treated is 30,000
cubic yards (37,000 tons), which is representative of a typical
Superfund site. It is important to note that the cost per ton of
treated material will decrease as the total quantity of raw
material increases and fixed costs are averaged over more raw
waste. During the SITE demonstration, waste material was
processed at an average rate of 15 tons per hour, which is
significantly lower .than the designed rate.
The Chemfix cost model (Table 4-1) was the basis for the
economic analysis. Information provided by Chemfix includes
a range of expected costs for reagents, labor, miscellaneous
operating expenses, and equipment lease as well as an estimate
of mobilization and demobilization costs. Cost figures are
generally represented in dollars per ton of raw waste. Total
cost can be influenced by the rate at which material can be
processed because lower processing rates result in higher
costs per ton for equipment lease and labor.
Waste Treatment Costs by Category
Costs associated with the Chemfix technology are de-
fined below in 12 cost categories. These categories reflect
typical cleanup activities at Superfund and RCRA corrective
action sites. This section provides cost information for each
category and forms the basis of the cost analysis presented in
Table 4-2. Fixed costs refer to costs that are independent of
the amount of waste treated. Variable costs are directly de-
pendent on the quantity of waste processed by Chemfix.
Site Preparation Costs
Site preparation costs include those for planning and
management, system design, auxiliary and temporary equip-
ment and facilities, legal searches, access rights, preparation
of support facilities, minor cleaning of the site, emergency
and safety equipment, utility connections, and site support
staff. Site preparation costs depend on the type and condition
of the site where treatment takes place. The Chemfix cost
model estimates $5,000 for site preparation. The range is
estimated to be $5,000 to $50,000.
The Chemfix cost model includes costs for many of the
activities associated with site preparation and with direct
mobilization, use, and demobilization of the Chemfix technol-
ogy. However, the Chemfix model may underestimate site
preparation costs. Considerable costs may be associated with
getting a Superfund site ready for a cleanup action, excavating
wastes, and clearing the site after the treatment process. Such
activities involve setting up decontamination facilities, estab-
lishing telephone lines to the site, preparing gravel roads and
parking areas, excavating wastes, backfilling the excavation,
sample collection, and monitoring health and safety conditions.
Many of these activities are labor intensive. A conservative
estimate assumes 500 hours of labor at $50 per hour plus costs
for utility service hookup and sample collection. Waste exca-
vation costs are excluded in this estimate, but can be estimated
at $40 per ton.
Additional materials handling and pretreatment costs must
also be considered according to site requirements. Costs for
these activities vary significantly depending on the character-
istics of the waste being treated. The Chemfix process equip-
ment does not include screening or particle size reduction
equipment. This must be rented or purchased in addition to
leasing the Chemfix equipment
Permitting and Regulatory Costs
Permitting and regulatory costs vary depending on whether
treatment is performed on a Superfund or a RCRA corrective
action site and on how the treated material is disposed of.
Section 121(d) of CERCLA as amended by SARA requires
that remedial actions be consistent with ARARs for environ-
11
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Table 4-1. Chemftx Cost Model
Category
Rate
EPA Commentary
Processing Costs
Labor Cost
Reagent Cost
Miscellaneous operating
expenses and maintenance
cost (includes health and
safety cost)
Equipment Lease*
Mobilization and Demobilization Costs'
Equipment transfer expenses
Labor costs with expenses
Miscellaneous site expenses
Travel expenses for crew
$5 to $15 per ton. Will vary with Realistic"
processing rate and quantity to be
processed.
$25 to $30 per ton. Will vary with Realistic
moisture content of Waste (moisture
or lack of moisture in soil).
$2 to $4 per ton. Realistic
$3 to $5 per ion. Will vary with Slightly low
processing rate.
$250 per loaded mile per truck Realistic
(from point of origin and return).
$380 per day per person. Realistic
$100 per day. Very low
$500 per person. Realistic
* Costs of labor and equipment shown here are realistic for the Chemfix process only. Labor and equipment needed to get the
waste to the treatment unit (excavation and materials handling) approximately double the costs shown here.
*This assumes that Chemfix process equipment is leased for use and does not represent the capital investment required for
purchasing the equipment.
'Mobilization and demobilization costs are one-time costs per job. Equipment transfer expenses vary based on distance from
Louisiana to the site.
mental laws, ordinances, regulations, and statutes. ARARs
include federal standards and criteria as well as more stringent
standards and criteria promulgated under state or local juris-
dictions. Applicable requirements are those for which juris-
dictional prerequisites of the underlying statute are satisfied.
Relevant and appropriate requirements do not legally apply to
the situation or action planned, but are nonetheless suitable
because of the characteristics of the remedial action, the
pollutants in question, or the physical circumstances at the
site. ARARs must be determined on a site-specific basis.
Permitting and regulatory costs are primarily incurred
through labor costs; the estimate of $25,000 is based on 250
hours at a labor rate of $100 per hour. Based on the capital
equipment total lease cost for 30,000 cubic yards of waste,
$25,000 is a reasonable estimate. This estimate does not
include relevant permit costs, which may vary significantly
depending on state and local requirements. At RCRA correc-
tive action sites, analytical protocols and annual monitoring
records must be kept, which increases regulatory costs. For
these situations, permitting and regulatory costs would be
higher. '
Capital Equipment Costs
Chemfix does not sell the patented process equipment
used for waste treatment. Moreover, for short-term on-site
remediations, it is not economically feasible to make the
capital expenditures required to purchase the equipment.
Therefore, Chemfix equipment must be rented from Chemfix
at a rate of $5,000 per week. This rental rate includes the cost
of the homogenizer, feed hopper, reagent units, mixer, and
other pumps and equipment
Assuming a weekly rate of $5,000, a processing rate of
160 tons per day, and a 7-day work week, the rental/lease cost
is approximately $5 per ton of raw waste. The Chemfix cost
model gives a range of $3 to $5 per ton. This cost does not
include the cost of obtaining pretreatment equipment or waste
storage.
Equipment Installation/Startup
Startup costs for the Chemfix process include those re-
quired to install the equipment, connect utilities, perform an
initial equipment shakedown, and initiate an environmental
monitoring program.
In the SITE demonstration of the Chemfix process, mo-
bilization of equipment at the test site took approximately 7
days. Miscellaneous site expenses for mobilization were about
$ 100 per day. Installation of power hookups cost about $2,050.
Expenses totaled over $5,500 for other equipment and mate-
rial used in the startup phase, including a crane to lift the
equipment into place, an arc welder, a trash pump, a four-way
cable pack, an air wrench, protective clothing for the crew,
and miscellaneous items. Therefore, the total cost of installa-
tion and equipment startup was approximately $8,500.
12
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Table 4-2. Estimated Costs ofCkemfix Treatment
Technology by Category*
Fixed Cost Category
Site Preparation''
Permitting and Regulatory
Equipment Installation and Startup
Trailer Transport to Site
Mobilization/Demobilization
Equipment Repair and Replacement
Effluent Treatment and Decontamination
Total Fixed Costs
Total Fixed Cost per Ton
Variable Cost Category
Estimated Costs
(1990$)
Capital Equipment Rent/Lease*
Labor
Chemfix Reagents
Utility and Miscellaneous
Analytical
Total Variable Cost per Ton
Total Treatment Cost
per Ton of Raw Waste
$50,000
$25,000
$8300
$12300
$ 12,000
NA*
$2500
$110,500
$3
Cost Per Ton of
Waste Treated
~$5
$27'
$30
$3
$70
$73'
"Based upon 30,000 cubic yards (37,000 tons) processed at
160 tons per day.
''Excludes excavation costs.
'Assumed to be included in the cost of renting/leasing
equipment from Chemfix.
d Based on the rent/lease cost of equipment from Chemfix.
Does not include costs for purchasing or renting screening
devices, size reduction equipment or waste/product storage
containers.
'Includes cost for an operations crew.
f Excludes the cost of raw waste or site environmental
sampling.
'Excludes the cost of possible post-treatment, curing,
storage, excavation, and final disposal.
Equipment Transport
The Chemfix cost model estimates transportation costs at
$2.50 per loaded mile per truck for the round trip between the
equipment point of origin (Baton Rouge, Louisiana) and the
site. The Chemfix equipment is transported on three to five
flat-bed trailers depending on the equipment capacity. The
cost analysis assumes a 1,000-mile trip for five Chemfix
trailers. Other equipment required for site preparation, pro-
cessing, and demobilization is assumed to be acquired locally.
Labor Costs
Chemfix estimates that its processing equipment requires
a crew of four to five workers. The crew includes four
technicians and one senior project engineer working 10-hour
shifts at hourly rates of $36.60 and $46.80, respectively. In
this scenario, die total daily cost of the crew is approximately
$1,900; including fringe and other indirect costs. Assuming
expenses of $100 per day per worker, the total labor cost to
run the Chemfix process equipment is approximately $2,400
per day.
Assuming that the processing rate is 160 tons per day, the
labor cost required for operating the Chemfix technology is
$15 per ton of treated material. This is consistent with labor
costs in the Chemfix model, which ranges up to $15 per ton,
including expenses.
In addition, a support crew is required to transfer exca-
vated soil and deliver it to the Chemfix equipment, to sample
soil and treated wastes, to monitor health and safety conditions,
and to direct the overall project. The support crew consists of
two technicians (a sampling technician and a health and safety
officer), two laborers (a backhoe operator and a general crew
member), and one resident engineer. Assuming 10-hour shifts
and fully loaded hourly rates of $36.60, $31.50, and $46.80
for the technicians, laborers, and engineer, respectively, the
total daily labor cost for the support crew is approximately
$1,800. At a processing rate of 160 tons per day, this is an
additional labor cost of $11.25 per ton of waste treated.
Therefore the total labor cost is $26.50 per ton of waste
treated.
Supply and Consumable Costs
The principal consumables associated with the Chemfix
technology are reagents. The impact of reagent cost on the
Chemfix process depends on required reagent concentrations.
The exact portions of dry (CHEMSET 1-20) and liquid
(CHEMSET C-220) reagents in the Chemfix process are
proprietary information. Chemfix quotes a reagent cost range
of $25 to $35 per ton of material treated. This range is
generally consistent with costs associated with alternative
reagents that can be used for this type of stabilization/solidi-
fication process. For example, treatment reagents similar to
those used in the Chemfix process, such as portland cement
(30 percent by weight) and sodium silicate (2 percent by
weight), yields a cost of $21 per ton of waste treated. Alterna-
tive solidification/stabilization processes not using cement,
such as pozzolanic processes (for example, those based on the
reaction of flyash with lime), have similar reagent costs.
Flyash (Type F) (80 percent by weight of reagent) and lime
(20 percent by weight of reagent) can be used at a cost of $34
per ton of treated waste.
For the cost analysis, supply and consumables cost was
assumed to be $30 per ton of treated waste.
Utility and Miscellaneous Costs
The cost of utilities and other miscellaneous operating
expenses is estimated from the Chemfix cost model. The
estimated cost is $2 to $4 per ton of treated waste; $3 per ton
of treated waste was used in the cost analysis.
Effluent Treatment and Decontamination Costs
The Chemfix treatment process has no liquid effluent.
Personal protective equipment and monitoring instruments
may require decontamination. The cost of treating effluent
from decontamination procedures was estimated based on
13
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treating 2,000 gallons of water at $1 per gallon plus $500 in
transportation costs.
Analytical Costs
Analytical costs include those for laboratory analyses,
data reduction and tabulation, quality assurance/quality control
(QA/QQ, and reporting. These costs are for verification of
treatment effectiveness and do not include waste characteriza-
tion. Analytical costs will vary according to the types of
contaminants and regulatory requirements for the site.
The following assumptions were made for the cost analy-
sis. Analyses are conducted on a percentage of treated waste
to verify treatment effectiveness. The analyses include TCLP
and UCS tests at an estimated cost of $750 and $50 per
sample, respectively. Assuming one sample is collected and
analyzed per day, the total cost would be $5,600 for a 7-day
work week. This is equivalent to $5 per ton for the assumed
processing rate of 160 tons of waste per day.
Equipment Repair and Replacement Costs
Equipment repair and maintenance costs for the Chemfix
process are minimal. Chemfix supplies the principal equip-
ment, and repair costs should be covered in the leasing
agreement. Some costs may be incurred for maintenance of
non-Chcmfix equipment such as screens, grinding shredders,
or waste storage containers.
Mobilization/Demobilization Costs
Mobilization costs include miscellaneous equipment
transfer expenses, labor costs with expenses, miscellaneous
site expenses, and travel expenses for the crew. The Chemfix
model estimates a minimum of $6,000 for mobilization. Costs
for demobilization at the SITE demonstration, including costs
for garbage pickup, earth-moving equipment, plant disman-
tling, and protective clothing for the crew, totaled over $6,000.
Therefore, the cost analysis includes $12,000 for mobilization/
demobilization costs.
Residuals and Waste Shipping, Handling, and
Transportation Costs
The cost of treating wastes with Chemfix technology
varies with the disposal method for the treated material.
Placement on the original hazardous waste site or disposal in
an unlincd facility will be less costly than off-site disposal or
disposal in a RCRA Subtitle C facility. The cost of on-site
disposal in the excavation was approximated at $50 per ton.
The costs of residuals disposal in a Subtitle C landfill could
exceed $150 per ton.
Potential Additional Costs
Depending on the physical characteristics of the waste
and the chemical contaminants, the Chemfix process may not
provide a complete, effective remediation unless it is part of a
larger treatment train. Various pretreatment operations may
be required such as screening large particles, grinding (pul-
verization), soil washing, or an organics removal technology
to separate organic contaminants from the soil. Because waste-
specific considerations dictate the necessity of pretreatment
operations, they were not considered in the Chemfix cost
model. Land disposal of treated waste is another source of
additional costs that require consideration. Potential addi-
tional costs for solidification/stabilization processes are pre-
sented in Table 4-3.
Table 4-3. Potential Additional Costs for Solidification/
Stabilization Processes
Options Cost (per ton)
Screening
Grinding
Soil Washing
Organics Removal
Land Disposal
$
$
$
•$
$
3 to 7
05to2
100 to 400
250 to 600
50 to 250
Summary of Economic Analysis
The cost to solidify/stabilize waste material using the
Chemfix process is approximately $73 per ton of raw waste.
The cost analysis was based on process equipment capable of
treating an average of 160 tons per day. This rate is represen-
tative of requirements for a soil remediation at a Superfund
site.
Estimated treatment cost excludes the cost of waste exca-
vation, environmental site and waste characterization, raw
waste pretreatment, and curing, storing and disposal of the
treated waste. These costs were excluded because they are
either optional items subject to site-specific requirements or
are not directly associated with the treatment process. Appli-
cations of Chemfix technology should consider these items to
develop accurate cost estimates. Cost estimates for land dis-
posal of treated waste range from $50 to $200 per cubic yard.
The largest contributors to total treatment cost are the
proprietary reagents and labor. Reagent and labor costs ac-
count for 41 and 37 percent of the treatment costs, respec-
tively.
References
American Nuclear Society, 1986, American National Stan-
dard Measurement of die Leachability of Solidified Low-
Level Radioactive Wastes by a Short-Term Test Procedure,
prepared by the American Nuclear Society Standards
Committee Working Group, ANS 16.1. ANS, LaGrange
Park, Illinois.
American Society of Testing and Materials, 1987, Annual
Book of ASTM Standards. ASTM, Philadelphia, Pennsyl-
vania, Volume 4.08, March.
Chemfix Technologies, Inc., 1987, Propose SITE-002 for
Development of Innovative Technologies for Hazardous
Waste Site Cleanup. Metairie, Louisiana. Prepared for
U.S. EPA, HWERL, Cincinnati, Ohio. Chemfix Technolo-
gies, Inc.
Hazardous Waste Consultant, Materials that Affect Stabiliza-
tion/Solidification Processes, pp. 14-16, January/February
1988.
Salas, R.K., 1980, Disposal of Liquid Wastes by Chemical
Fixation/Solidification. The Chemfix Process, in Toxic
and Hazardous Waste Disposal, Volume One, R. Pojasek,
ed. Ann Arbor Science Publishers, Inc., Ann Arbor,
Michigan, 1980, p. 321-348.
14
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U.S. Environmental Protection Agency, 1979, Methods for
the Chemical Analysis of Water and Wastes. U.S. EPA 4-
70-020, March.
U.S. Environmental Protection Agency, 1986a, Prohibition on
the Placement of Bulk Liquid Hazardous Waste in Landfills,
Statutory Interpretive Guidance. EPA 530SW-86-016, June.
U.S. Environmental Protection Agency, 1986b, Test Methods
for Evaluating Solid Waste. U.S. EPA Volumes IA and H,
Third Edition, U.S. EPA Document Control No. 955-001-
00000-1.
U.S. Environmental Protection Agency, 1989, Superfund LDR
Guide #1, Overview of RCRA Land Disposal Restriction
(LDRs), U.S. EPA Directive 9346.3-01FS.
15
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Appendix A
Key Contacts for the SITE Demonstration
Additional information on the Chemfix technology, the
SITE program, and the demonstration site can be obtained
from the following sources.
The Chemfix Technology
Philip Baldwin
Chemfix Environmental Services, Inc.
2424 Edenborn Avenue, Suite 230
Metairie, LA 70001
(504) 831-3600
The SITE Program
SITE Project Manager, Chemfix Demonstration
Ed Earth
U.S. Environmental Protection Agency
Office of Research and Development
Risk Reduction Engineering Laboratory
26 West Martin Luther King Drive
Cincinnati, OH 45268
(513) 569-7669
SITE Program, EPA Headquarters
Jim Cummings
U.S. Environmental Protection Agency
Office of Solid Waste and Emergency Response
Office of Policy, Management, and Technology
401 M Street, S.W.
Washington, DC 20460
(202) 382-4362
The Demonstration Site (Portable Equipment Salvage
Company, Oregon)
John Sainsbury
U.S. Environmental Protection Agency (HW-093)
1200 Sixth Avenue
Seattle, WA 98101
(206)442-1196
16
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Appendix B
Vendor's Claims for the Technology
NOTE: This information was provided by CHEMFIX®
Technologies, Inc. It has not been edited or changed by
EPA.
Process Description of the CHEMFIX®
Technology
The CHEMFIX® Process is defined as a chemical fixa-
tion/stabilization technology. This patented process, enhanced
with proprietary developments, stabilizes mobile constituents
of concern within a waste matrix by chemical and physical
means.
The CHEMFIX® Process is based on the use of the
CHEMSET® C-220 family of poly-silicates and the
CHEMSET® family of dry calcium containing dry reagents.
This chemistry is assisted as needed by CHEMSET® reaction
promoter additives. The combination and proportions of re-
agents are optimized for each particular waste stream requir-
ing treatment.
The CHEMFIX® inorganic chemical system reacts with
polyvalent metal ions, certain other waste components, and
also with itself to produce a chemically and physically stable
solid material. The cross-linked, three dimension polymeric
matrix displays properties of good stability, high melting
point and stable, friable soil-like characteristics.
Three classes of interactions can be described within the
CHEMFIX® Process. First are the rapid reactions between
CHEMSET® poly-silicates, certain reaction promoters and
metal ions, producing insoluble metal silicates. Second are
reactions between the CHEMSET® C-220 molecules and the
reactive components, including calcium oxide within the
CHEMSET® dry reagent, producing a gel structure. Third are
hydrolysis, hydration and neutralization reactions between the
dry reagent and the waste and water (both free and contained).
There are no side streams or discharges resulting from the
CHEMFIX® Process. During processing, all the waste is
transferred to the process mixer wherein the reagents immedi-
ately react to form a gel. This gel is then discharged to the
receiving area. The viscosity of the gel varies depending on
the total solids of the waste stream prior to processing.
The CHEMFIX® Product (Naturfil) has been demon-
strated to exhibit long term stability. Multiple extraction data
on new and aged product indicates that the new ionic and
covalent bonds formed within the Naturfil matrix are as stable
as should be expected from such chemistries.
CHEMFIX® Process Description
The schematic of the CHEMFIX® treatment system is
presented in Figure 1. The system consists of a feed hopper,
primary conveyor, weigh feeder, high speed shear process
mixer (homogenizer), CHEMSET® 1-20 dry reagent storage,
CHEMSET® C-22 or C-220d (dilute C-220) liquid reagent
tank, two alarm and control panels instrumentation, high shear
process mixer and other equipment.
A simplified process description can be obtained by
tracing the flow of the soil through the treatment system. This
system can be divided into two parts: (1) Preparation and (2)
Treatment
The first step in preparation is the transfer of soil from the
soil storage area to the soil feed hopper. This hopper has a
capacity of 15-20 cubic yards. From the hopper, the soil is
then lifted by a primary conveyer to the weigh feeder. The
amount of soil to be processed is measured at the weigh
feeder. From this, the soil is gravity feed into a high speed
shear process mixer (homogenizer) where the water is added.
If additional pre-treatment chemicals are required, they would
also be blended at this point. A signal representing the weight
of the soil to be processed is transmitted to a flow-indicating
controller that regulates the flow rates of water to the soil.
Water is introduced through a nozzle into the homogenizer to
obtain optimum mixing. The ratio of added water to soil can
be set at the flow-indicating controller to obtain the homog-
enizer can be controlled from the alarm and control panel.
The second part of the process, soil treatment, begins as
the soil-water mixture is transferred from the homogenizer to
the process mixer. The CHEMSET® 1-20 and CHEMSET®
C-220 are added to the process mixer, which uses a
CHEMFIX® designed pug mill to blend all the ingredients.
The CHEMSET® 1-20 is fed into the process mixer through a
dry reagent feeder from the storage silo. The CHEMSET® C-
220 is pumped from the liquid reagent storage tank by a
positive displacement pump. The proper feed rates for the
liquid and dry reagents are regulated at the control panel.
The final NATURFIL® fixed product is discharged from
the mixer into a storage bin and transported to the temporary
storage area for final curing.
CHEMFIX® Equipment Description
The CHEMFIX® soil treatment system is a self-con-
tained unit mounted on a flat-bed trailer. The system consists
of distinct pieces of equipment that, when assembled, are
17
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connected together both physically and electronically. This
section discusses each of these distinct pieces of equipment
and its function in the processing unit
Feed Hopper
The feed hopper is where waste material to be treated is
introduced, by the front-end loader or other earth-moving
equipment, into the treatment system. The CHEMFIX® feed
hopper to be used during the SITE demonstration site has an
approximate dimension of 9 x 16 feet and a capacity of 15-20
yards per hour.
Primary Conveyor
Waste material from the feed hopper is transferred by
conveyor to the weigh feeder.
Weigh Feeder
The weigh feeder receives waste material from the pri-
mary conveyor and continually weighs the waste that enters
the high speed process mixer. The feeder is electronically
connected to the water flow control system and the two
CHEMSET® reagent feed systems. Waste is moved through
the weigh feeder to the homogenizer. The weight of the soil
will regulate the water flow rate to the homogenizer through a
flow-indicating controller and a water flow control station.
Water Flow Control System
The water control system receives an electronic signal
from the weigh feeder signaling the amount of waste entering
the homogenizer. This system then adds water to the waste at
a predetermined rate as the waste passes into the homogenizer.
High Speed Shear Process Mixer
The high speed shear process mixer receives waste mate-
rial from the weigh feeder and water from the water flow
control system. The amount of water that is added is measured
by a flow meter and is determined by the amount of waste
passing through the weigh feeder.
CHEMSET® Dry Reagent Feeder
The CHEMSET® used in the process is transported to the
treatment site and stored in a silo. From the silo it is transferred
by an auger to the process mixer. The speed of the auger is
controlled in conjunction with the CHEMSET® C-220 or
C220d (dilute C-220) by the control panel. The design capac-
ity of the CHEMSET® 1-20 feeder is 0-54,000 Ibs per hour.
CHEMSET® 1-20 Storage Silo
The silo has a capacity of 120,000 Ibs and is equipped
with a level sensor for high and low levels. When 1-20 reaches
a low level, an alarm will sound. The silo is also equipped
with a baghouse collector. The collector is operated only
during the transfer of 1-20 from the bulk reagent storage
transport vehicle to the silo.
CHEMSET® C-220 Storage Tank
The 10 foot diameter C-220 storage tank, which has a
100,000 Ib capacity, is used to hold reagent as needed for the
process. The tank is outfitted with a transfer pump and the
system may be heated when the temperature is below 45°F.
Liquid Transfer Pump
The pump rate is manually set on the control panel and
varies according to the signal received from the weigh feeder.
High Shear Mixer
Wetted waste material from the homogenizer, 1-20 silo
and C-220 tank are mixed. The waste material is transferred to
the process mixer by gravity. The C-220 liquid reagent is
pumped to the process mixer and the 1-20 dry reagent is
transferred to the mixer by an auger. In the mixer, these three
ingredients are mixed and then discharged either directly or
by a positive displacement or centrifugal pump to the disposal
area, waste containers or solidification cells.
Wastes Compatible with the (Stabilization/
Fixation) Technology
1. See the attachment, "Partial List of Wastes Suitable for the
CHEMFIX® Treatment."
2. Liquid wastes that contain a minimum of 3%-5% solids
are reasonably considered treatable with the Technology
for heavy metals fixation/stabilization.
3. Solid wastes are treatable for heavy metals with the Tech-
nology either as is or with pre-treatment. Solid wastes
should have about 30% moisture available for chemical
reaction (this can be added as a part of the reagent additions)
and the waste particle size usually needs to be less than
100 mesh prior to reagent addition. Particle size reduction
may occur within the Technology mixing equipment or
pre-grinding may by required.
4. Volatile organics can only be addressed by the Technol-
ogy if the level is extremely low, i.e., typically less than
100 ppm. Special CHEMSET® reaction additives are
required in these applications.
5. Semivolatile and high molecular weight petrochemicals
can be addressed on a case-by-case basis, with or without
using CHEMSET® reaction additives. This is an area of
new development for the Technology.
6. Heavy metal treatment has been demonstrated possible
with the Technology, in the presence of 5%-10% by
volume oil and grease.
Favorable Conditions for Execution of the
Technology
The outdoor temperature should be above 45 degrees
Fahrenheit if the Technology is to be practiced outdoors, or if
the curing time is critical and there is ho heated space in which
the finished product can cure. A stabilized product that would
cure substantially within hours at 55-60°F will take 48-60
hours at 45°F and 96+ at 35°F.
Advantages of the Technology
1. The Technology thoroughly treats all of the waste to the
same standards, allowing the establishment of a superior
Quality Assurance program.
2. Stabilized waste has soil like qualities and can be reused as
a soil substitute. This synthetic soil usually has much
greater erosion resistance, enhanced slope stability, and
can trap soluble heavy metals and sweeten landfill leachate.
18
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3. The Technology produces a synthetic soil that has
permeabilities in the soil range, i.e., IxlO5 to IxlO7 cm/sec
range.
4. When amended with some natural soil to assist in moisture
retention and nutrient supply, the Technology will produce
a synthetic soil that may be used to support vegetation as a
topsoil.
Site Application of the Technology
1. Mobile locations where solid or liquid wastes require
stabilization and/or fixation are important applications of
the Technology.
2. Fixed facilities at a specific generator's plant location are
many times economical and convenient for the generator.
3. The Technology can be applied at a Central Treatment
Facility where waste are brought from many different
generators.
Cost Information on the Technology
1. Mobilization and any required demobilization costs are a
function of where the waste site is and what type of waste
and quantity is involved. The cost of mobilization/instal-
lation could range from as little as less than $10,000 to
more than $100,000.
2. CHEMSET® treatment reagent costs will also vary, with
wastes with less than 20%-30% moisture being more
expensive to treat than liquid wastes. A reasonable range
of reagent costs will lie within a $25-$35 per ton spread.
3. Capital budget expenses, based on a 250 ton day year and
a five year depreciation schedule (including mobile jobs),
should be considered to be in the range of $3-$6 per ton.
These numbers may not be valid if the volume processed is
small.
4. Miscellaneous operating and maintenance expenses should
be budgeted in the $2-$4 per ton range.
5. Labor varies depending on the type and size of operation.
A modest to large size job will require 4-5 workers including
onsite supervision management
6. Quality control and quality assurance laboratory work will
greatly depend on the job and State requirements. Standard
RCRA testing is to be expected, i.e., TCLP or EP leachate
testing for metals and potentially some organic components
that might be present. The addition of organic testing can
substantially increase the cost of any QA/QC program.
7. There are no side streams produced with the Technology.
Only wash waters which can be saved and reintroduced
into the process for stabilization.
8. Liquid wastes can be treated at the rate of from 200-300
gallons per minute per processing unit. Solid wastes can be
treated in the range of from 200-500 cubic yards per day.
9. Finished product disposal varies significantly depending
on the project program. The final product could be re-used
onsite if the waste has been rendered non-hazardous via
"de-characterization" or "delisting." The waste could be
re-used as a soil enhancement at a disposal facility.
Mobilization-Demobilization Costs
Project: Treatment of contaminated soils.
Mobilization From: Kenner, Louisiana
Truck trailers typically required: Three
Men typically required: 4 operating technicians, 1 supervi-
sor plus an electrician
Set up time at the site: Typically 1 week
Shakedown period, minimum: 1 week
Equipment transfer expense: $2.50 per loaded mile from
Kenner to the site, times three trucks
Example:
Process site distance: 1000 miles
Manpower costs per day with expenses: $380.00 x 6 = $2,2807
day x 14 = $31,920.00.
Misc. site expenses: $100/day x 14 = $1,400.00.
Equipment transfer: 3 x 1000 miles x $2.50 = $7,500.00.
Travel expenses for crew: 6 x $500.00 = $3,000.00
Minimum expected mobilization and installation costs =
approx. $45,000.00
Demobilization expenses vary depending on distance and
the QC cleaning program that is required by the controlling
Agency. This total cost could range from 60%-75% of the
mobilization costs to as much as the mobilization/installation
expenses.
Reagent Costs
A typical soil would be processed at a per ton cost of $25-
30. One of the important variables is the moisture or lack of
moisture in the soil.
Labor Costs
This includes training required plus periodic medical
exams. A typical project will require 4 to 5 personnel with an
expected cost of about $5 to $15 per ton, depending on the
speed of the processing and size of the job.
Miscellaneous Operating Expenses w/
Maintenance
Budget a typical $2 to $4 per ton.
Capital Equipment Costs
Budget a typical $3 to $6 per ton, depending on the speed
of the processing.
Operating Rates
Budget a typical quantity of soil to be processed in a 10
hour work shift at 200-400 tons.
19
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Appendix C
SITE Demonstration Results
The Chemfix solidification/stabilization technology was
demonstrated and evaluated under the SITE program at the
Portable Equipment Salvage Company (PESC) site in
Clackamas County, Oregon, in March 1989. The PESC site
was an electrical transformer and metal salvage facility from
the 1960s to 1985. Its operations involved scrapping and
recycling power transformers containing oils with PCBs. Ac-
tivities at the site left the soil heavily contaminated with lead,
copper, zinc, and PCBs. The objective of the SITE demonstra-
tion was to determine the following:
• The ability of the Chemfix process to create a stabilized
waste that would meet land disposal restrictions (LDR)
requirements for heavy metal wastes (F006) and lead.
Specifically, lead concentrations of less than 0.51 mg/L in
the TCLP extract and a demonstration-specific soil con-
centration of 5.0 mg/L were used as benchmarks to evaluate
the process.
• The effectiveness of the Chemfix process in reducing the
mobility of heavy metals flead, zinc, and copper) and
PCBs. Treatment effectiveness was measured by compar-
ing TCLP test data from before and after solidification/
stabilization.
• The ability of the Chemfix process to dechlorinate PCBs.
• The extent to which the Chemfix process alters chemical
and physical properties of wastes, and the effect of any
alterations on the long-term stability of treated wastes.
• The costs and major cost factors associated with the
Chemfix process.
For the SITE demonstration, four on-site locations (Areas
A, C, E, and F) were selected for treatment by Chemfix. These
locations differed in soil type and contaminant concentration.
During the demonstration, Chemfix treated waste from each
of the designated areas. Table C-l summarizes objectives of
the demonstration, test methods, and results. A detailed de-
scription of demonstration results can be found in the Tech-
nology Evaluation Report.
The contaminated waste was extensively sampled and
analyzed before and after treatment to determine the effec-
tiveness of the Chemfix process in immobilizing contami-
nants. Specific analytical procedures used for the demonstration
are listed in Table C-2. Analyses conducted on the waste may
be grouped into four classes: leaching tests, chemical tests,
physical tests, and tests for PCB dechlorination. In addition,
air monitoring was conducted during the demonstration to
determine whether PCBs were released to the air as the
technology was implemented. Materials balance data were
also collected during the demonstration.
Leaching Tests
The TCLP PCB and metal analyses of the extracts were
performed on five duplicate samples of raw and treated soil
from each test run to determine percent reductions as a result
of treatment. Additional leaching procedures were used to
evaluate chemical stability and leaching potential of raw and
treated wastes. These procedures included the multiple ex-
traction procedure (MEP) and the American Nuclear Society
Test 16.1 (ANS 16.1). ANS 16.1 was used only for the treated
waste products.
TCLP
The TCLP is used to evaluate the potential for contami-
nants to be extracted from waste when codisposed with mu-
nicipal waste in a landfill. The TCLP is the basis for lead
regulations under the LDRs of RCRA. Because the TCLP is a
regulatory test for RCRA hazardous wastes, it is a measure of
the potential of the Chemfix technology for future applications.
Concentrations of lead, copper, zinc, and other metals in
TCLP extracts of treated waste were substantially reduced
compared to those of raw waste. PCBs were not found in any
TCLP extracts. Table C-3 presents the percent reductions of
mean TCLP-extractable lead, copper, and zinc.
The SITE demonstration was designed to test the ability
of the Chemfix process to meet potential regulatory standards
under RCRA. LDRs are likely to be considered ARARs for
Superfund wastes treated by the Chemfix process. However,
several land ban standards could also apply to waste treated at
this demonstration.
Results of the extraction study were compared to three
standards: (1) 0.51 mg/L of lead in the TCLP extract; (2) 99-
percent reduction in lead in the TCLP extract following
treatment; and (3) 5.0 mg/L of lead in the TCLP extract The
0.51 mg/L standard is based on the standard for lead in
electroplating wastes. The 99-percent reduction standard is
discussed in the EPA interim Superfund policy for soil and
debris. For wastes with initial concentrations of lead greater
than 300 ppm in TCLP extracts, the treatability variance under
the LDR requires treatment to achieve 99-percent reduction in
lead in the TCLP extracts. The 5.0 mg/L standard is analogous
to that used for definition of a characteristic waste (D008).
Although the definition of a characteristic waste is based on
20
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Table C-l. Summary of Demonstration Objectives, Test Methods, and Results
Objective
Approach/Method
Results
Primary
• Determine whether wastes treated by the
technology meet or exceed RCRA land
ban standards for lead.
Secondary
Determine the effectiveness of the process
in reducing lead, zinc, and copper con-
centrations in leachates obtained using
the TCLP on raw and treated wastes.
• Determine the effectiveness of the process
in reducing PCS concentrations in TCLP
extracts to 1 ppm or less.*
• Determine whether the treatment process
dechlorinatesPCBs over time.
Determine baseline physical properties
of raw wastes to establish a basis for
evaluating process performance.
Determine the chemical properties of the
raw wastes to establish a basis for
evaluating process performance.
Determine physical properties of treated
wastes to indicate their long-term
permanence and placability.
Determine chemical properties of treated
wastes.
Compare lead concentrations in TCLP leachates of
treated wastes to chosen demonstration standard of
5.0 mglLfor soil and RCRA-listed wastes
(electroplating sludges') standard of 051 mglL.
Compare TCLP lead, zinc, and copper concentrations
in TCLP leachates from treated wastes with those
from raw wastes. These percent reductions were
compared to interim standards for Superfund soil and
debris for RCRA land ban.
Compare PCB concentrations in TCLP extracts from
treated wastes with those from raw wastes.
Compare PCB concentrations in treated wastes at 15,
30,45, and 60 days after treatment using EPA
Method 680. Identify the presence of reaction
products using a new analytical approach to determine.
whether dechlorination rather than adsorption has
occurred during the curing process.
Analyze raw wastes for particle size, percent moisture,
standard proctor value, porosity, bulk density; and
specific gravity.
Analyze raw wastes for acid neutralization capacity,
TOC, pH, Eh, oil and grease, electrical conductivity,
total PCBs, total lead, total copper, lead compounds,
humic acid, and dioxin.
Subject treated wastes to permeability, wet/dry,
freeze/thaw, water content, bulk density, specific
gravity, and porosity tests.
Analyze raw wastes for acid neutralization capacity,
TOC, pH, Eh, oil and grease, electrical conductivity,
total PCBs, total lead, total copper, lead compounds,
humic acid, and dioxin.
70% of samples met the demonstration standard. 65%
of samples met the RCRA land ban standard.
Percent reductions of mean TCLP lead, zinc, and
copper concentrations from untreated to treated
wastes were 935 to 999 for lead and 95.5 to 99.4 for
copper.
PCBs were not found in the TCLP extracts of raw
wastes. Therefore, no conclusions could be drawn.
Data suggest the partial dechlorination of PCBs to less
chlorinated congeners. No evidence of total
dechlorination of PCBs to another compound was
found. Partial dechlorination may not be due to the
stabilization process.
See Table C-4.
See Table C-4.
Results show that UCS is relatively constant after
14 days. Products showed resistance to freeze/thaw
and wet/dry weathering tests.
The acid neutralization capacity, electrical conductivity,
andpH of the wastes increased dramatically with
treatment. Eh was lower after treatment.
(continued)
* This objective was dropped because PCB concentrations in the TCLP extracts of raw and treated wastes (preliminary sampling) did not exceed detection levels.
-------
TabJeC-L (Continued)
Objective
Approach/Method
Results
Secondary (continued)
• Determine extraction and leaching
properties of treated wastes to indicate
their long-term chemical stability.
Determine the homogeneity of mixing
and structural characteristics of the
treated wastes.
Determine whether significant PCB
concentrations are released to the air
by the treatment process.
Determine dilution effects on any
reductions of lead and copper
concentrations in leachates obtained
from treated wastes.
Determine effects of aging on the
teachability, acid neutralization capacity,
and strength of treated wastes.
Determine total cost and major cost
factors associated with the process.
Subject treated wastes to a number of different
extraction and leaching tests.
Conduct x-ray diffraction, petrograpkic, and scanning
electron microscopy examinations of treated and raw
wastes.
Monitor PCB concentrations in the air near the
Chemfix equipment during the treatment process.
Measure the mass of wastes, water, and treatment
reagents used in each test run. Use these
measurements to calculate dilution factors.
Conduct x-ray diffraction, petrographic, and scanning
electron microscopy examinations of treated and raw
wastes.
Evaluate costs of all materials, equipment, and services
needed to complete the demonstration.
Mean lead concentrations in MEP extracts from
posttreatment samples generally exceeded the RCRA
regulatory level of 5 mg/Lfor the first extraction.
Mean concentrations from the last two extractions
showed an upward trend.
The ANS 16.1 leaching results suggest that diffusion is
the controlling mechanism of contaminants from the
matrix. The results met the NRC standard for the
teachability index. However, calculated fluxes from
this test should be used in a ground-water model for
site-specific applications.
These studies are on a scale too small to allow
conclusions regarding the product as a whole.
No significant increase in PCB concentration was
found during the treatment process.
Dilution factors for treated wastes varied between 133
and 1.40.
No major changes were detected after 6 months.
Costs were as follows: $73 per ton of new waste;
$50,000 for site preparation exclusive of excavation;
plus cost of placement or land disposal.
-------
Table C-2. Analytical Procedures Used for the SITE Demonstration
Test
Method
Leaching Tests
TCLP
ANS16.1
BET
MEP
Chemical Tests
pH
Eh
Electrical Conductivity
Acid Neutralization Capacity
Total Organic Carbon (TOC)
Humic Acid
Oil and Grease
Volatile Organic Compounds (VOCs)
Semivolatile Organic Compounds (SVOCs)
PolychlorinatedBiphenyls (PCBs) and Pesticides
Dioxins andFurans
Metals
Lead Compounds
Total Dissolved Solids (TDS)
PCB Dechlorination
Engineering/Geotechnical Tests
Particle Size Analysis
Water Content
Bulk Density
Specific Gravity
Wet/Dry Weathering Test
Freeze/Thaw Weathering Test
UnconfinedCompressive Strength (UCS)
Immersion UCS
Hydraulic Conductivity
In Situ Hydraulic Conductivity
Slump of Portland Cement Concrete
Standard Proctor Test
Petrographic Examination
40 CFR Part 268 (Federal Register, 1986)
ANS 16.1
Modified TMSWC-6 (Cote, 1988)
EPA Method 1320
EPA Method 904519040
Modified EPA Method 9045
ASA 10-3.3
TMSWC-7
ASA 29-33.2
ASA 30-3 2
EPA Method 413.2
EPA Method 8240 for VOCs
EPA Method 8270 for SVOCs
EPA Method 8080 for PCBs and Pesticides
EPA Method 8280 for Dioxins and Furans
EPA Methods 6010, 7060, 7421,
7740, 7841, 7470, 7471 for Metals
WRIMethod"
EPA Method 160.1
EPA Methods 680 and 3540 and RMC Methods'"
ASTMD422
Modified ASTM D2216/TMSWC-4
ASA 13-2/TMSWC-2
ASTMD854
ASTMD4843-88 (Draft)
ASTMD4842-88 (Draft)
ASTMD1633
Modified ASTM D16331 ASTM C39
EPA Draft Protocol (CSS-13)
ASTMD3385-75
ASTM C143
ASTMD698
ASTM C856
"Lead compounds were determined using the method developed by Western Research Institute.
*One of the two PCB dechlorination analyses were conducted using procedures developed by RMC Environmental and
Analytical Laboratories, Inc.
23
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Table C-3. Mean Concentrations of Metals in Untreated and Treated Material from SITE Demonstration
Lead
Area A
AreaC
AreaE
AreaF
Copper
Area A
AreaC
AreaE
AreaF
Zinc
Area A
AreaC
AreaE
AreaF
Mean Concentration
In Untreated
Waste
(Total, mg/kg)
21,000
140,000
92,000
11,000
18,000
18,000
74,000
33,000
Ij&OO
4200
8,000
5,100
Mean Concentration
In TCLP From
Untreated Waste
(mg/L)
610
880
740
390
45
12
120
120
16
30
71
42
Mean Concentration
In TCLP From
Treated Waste
(mg/L)
<0J0
25
47.0
0.10
057
054
0.65
0.60
0.024
025
4.8
0.03
% Reduction
In Mean
TCLP
Concentrations3
>99.9
99.7
93.6
99.9
98.9
95.5
99.4
995
99.8
99.1
93.2
99.9
'The effect of dilution from addition of reagents and water was not taken into account.
results of the extraction procedure (EP) test and not the TCLP,
the two extractions are similar for inorganic contaminants in a
very alkaline matrix.
Data from TCLP tests were evaluated by comparing
individual sample results to the previously described standards.
Seventy percent of the TCLP extracts met the 99-percent and
5.0 mg/L standards, and 65 percent met the 0.51 mg/L standard.
American Nuclear Society 16.1 Test
The ANS 16.1 test is used by the nuclear industry to
identify mechanisms that control leaching. It indicates the
amount of potential leaching from a monolithic solid. This
leaching procedure is used to simulate contact of solidified
wastes with ground water. Because material is not ground as
part of the test as it is in other extraction tests, ANS 16.1 test
results provide information on the structural ability of the
solidified waste to contain contaminants.
Several facts should be considered in reviewing results of
this test. The test is normally conducted on monolith-like
solids generated by solidification/stabilization projects in the
nuclear power industry. Although the ANS 16.1 test was
applicable to the solid produced during the SITE demonstra-
tion, the Chemfix process does not always produce a mono-
lithic solid. Therefore, ANS 16.1 test results may have limited
applicability to other uses of the Chemfix technology. The
ANS 16.1 test was not performed on untreated waste because
it was friable soil.
Mean leachate lead concentrations in die ANS 16.1 test
extract increased from 0.2 to 2.3 mg/L as the test progressed
from an initial contact period of 2 hours to 43 days. Mean
leachate copper concentrations per extract increased from
0.05 to 0.28 mg/L over diis time. A concurrent increase in
mean leachate pH values occurred and ranged from 9.9 to
11.0.
Leachability indices were calculated from results for
lead, copper, zinc, and arsenic. The leachability index for lead
exceeds the Nuclear Regulatory Commission's leachability
index standard of 6 by several orders of magnitude.
Multiple Extraction Procedure
The MEP was performed on raw and treated waste samples
from Area C. This procedure was used to determine extraction
properties of the waste. The RCRA EP toxicity extraction
procedure was used, followed by nine sequential extractions
with acidified, distilled water.
The test was included as part of the demonstration because
worst-case results of the test have been used in EPA models
for delisting RCRA-listed hazardous wastes. The models as-
sume a specific facility scenario and evaluate health effects to
a receptor at that facility from exposure to the leachate. Results
from EP toxicity extraction can be used to determine whether
the waste is a characteristic waste.
Lead, copper, and zinc were found in the first extraction
of the MEP as well as in acidified water extractions of raw and
treated waste samples. Mean lead concentrations in the origi-
nal EP toxicity extraction were 663 and 332 mg/L for raw and
treated waste, respectively. Mean lead concentrations increased
over time in some replicates. This increase suggests that the
24
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treated material may leach as time elapses after disposal if the
buffering capacity and structural integrity of the waste matrix
decrease.
Interpretation of Leaching Test Results
Extraction test results from TCLP and MEP were evalu-
ated by plotting lead concentrations in the extracts against the
final pH of extracts from raw and treated waste samples from
all waste collection locations. These relationships are displayed
in Figures C-l and C-2. These figures resemble the normal
shape of the solubility curve for lead, with the concentration
of lead in the extracts decreasing as the pH moves above 4.
The concentration is generally less than 1.0 mg/L between 8
and 10 pH units and increases as the pH climbs above 10.
Results of the leaching tests indicate that pH is a major factor
controlling leaching from the stabilized and solidified waste.
Chemical Tests
Chemical characteristics determined for the waste in-
clude pH, Eh, electrical conductivity (EC), total organic car-
bon (TOC), acid neutralization capacity (ANC), oil and grease,
metals, VOCs, semivolatile organic compounds (SVOCs),
polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated
dibenzofurans (PCDFs), pesticides, PCBs, lead compounds,
and humic acid. Table C-4 summarizes results of chemical
tests performed on raw and treated soil samples from the
PESC site.
The increase in pH (from approximately 7 before treatment
to 11 after treatment) is consistent with the alkalinity associ-
ated with cemerititious additives in Chemfix solidification
reagents. Eh is a measure of the reduction/oxidation potential
of the material. The decrease in Eh indicates a less oxidizing
environment as a result of treatment. The increase in the EC
treatment indicates an increase in the number of ions in
solution, suggesting that dissolution of the matrix is occurring.
This dissolution may be the result of addition of soluble
(nontoxic) compounds in the reagent mix or the solubilization
of waste components after treatment.
The increase in ANC of posttreatment samples reflects
the amount of alkaline reagent added to waste in the treatment
process. The metals concentration is represented in Table C-4
by the concentration of lead in the waste. The lead concentra-
tion, as well as concentrations of copper and zinc, varied
considerably from area to area and within areas. Any apparent
decrease in metals concentrations between raw and treated
waste samples may be attributed to the variability of the
original wastes or to dilution of the material with reagents
added during the treatment.
VOCs were not detected in raw waste from Areas A, C,
and E. Samples from Area F contained approximately 0.8 mg/
kg tetrachloroethylene. This concentration decreased slightly
after treatment, presumably because of volatilization during
treatment, dilution, or chemical encapsulation. Raw wastes
from Areas A, E, and F contained several SVOCs, mostly
benzene and pyrene derivatives in concentrations ranging
from 2 to 7 mg/kg. The Chemfix process did not reduce
SVOC concentrations.
Oil and grease, TOC, PCBs (Arochlor 1016 and 1260),
dioxins, and furans were not affected by the Chemfix process.
Physical Tests
Physical tests performed on raw and treated waste in-
cluded particle size distribution, water content, bulk density,
specific gravity, hydraulic conductivity, UCS, immersion UCS,
wet/dry weathering, and freeze/thaw weathering. Table C-4
summarizes the results for water content, bulk density, specific
gravity, porosity, and hydraulic conductivity. Data from the
UCS, immersion UCS, wet/dry weathering, and freeze/thaw
weathering tests are discussed below.
Unconfined Compressive Strength
UCS was measured on nine sets of treated samples aged
for 14, 21, and 28 days. Each sample set represents the
Chemfix product at a specific time during the treatment
process and includes three split samples, one for each test
time. Samples were cured on-site for 2 days before shipment
to the laboratory for analysis. Wet and cold conditions on-site
were not ideal for curing.
Results of the UCS test for Area C indicate that the
product of the Chemfix process meets the EPA guidance of 50
psi for placement in a landfill. These results also suggest that
the UCS value does not change significantly after curing for
14 days. Chemfix staff indicated that solidified/stabilized
waste generally sets up in a very short time, within 24 to 72
hours.
Results of UCS tests on samples taken throughout the
treatment process show that the UCS of the samples varies
considerably from 250 to 130 psi, in the first 2 to 4 minutes of
treatment The UCS decreases to an average of approximately
90 psi after 9 minutes of treatment.
Immersion UCS Test
UCS has two components. Part of the strength of a cured
product is the result of particles drying in a matrix, and part of
the strength comes from actual adhesion between particles.
The immersion UCS test distinguishes between these compo-
nents. If there is no reduction in strength after prolonged
immersion in water, the product demonstrates real adhesion
between particles. There is no generally accepted standard for
this test, but it is included in this demonstration for compari-
son with the UCS test.
Eighteen treated waste samples from Area C were im-
mersed in water. Six cores, one from each of the first sampling
boxes, were removed at 30,60, and 90 days after immersion.
Mean UCS values for each test period were 177 psi for day 30,
188 psi for day 60, and 204 psi for day 90. Results indicate no
decrease in strength as the result of increasing periods of
immersion. These data suggest that the strength of the solidi-
fied product is the result of adhesion between particles of the
matrix.
Wet/Dry Weathering Test
Wet/dry weathering tests were performed on molded
samples of treated waste from Area C according to method
TMSWC-12. Results from these tests are expressed as the
cumulative weight loss through 12 wet/dry cycles, normalized
to a control sample not subjected to the wet/dry weathering
test. Results of tests for all replicates indicate that less than 1
percent of the core weight was lost after 12 wet/dry cycles.
25
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10000
1000- -
100--
10 ••
1 * '
.1
*A
A
A
Figure C-1.
PH
10
11
12
13
Summary of extraction data for raw waste TCLP and MEP data from all areas.
10000
1000
100- •
10
.1 • •
.01
5
Figure C-2.
A
8
9
pH
10
11
12
Summary of extraction data for treated waste TCLP and MEP data from alt areas.
13
26
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Table C-4. Chemical and Physical Test Results
pH(pH units)
Eh (mil)
Electrical Conductivity (\unhos)
Total Organic Carbon (%)
Acid Neutralization Capacity (meg/g)
Oil and Grease (wt %)
Total Lead (mg/kg)
Arochlor 1016 (mgfkg)
Arochlor 1260 (mg/kg)
Water Content (wt %)
Bulk Density (g/cm3)
Specific Gravity
Porosity (%)
Hydraulic Conductivity (cm/s)
Before Treatment
65-75
140-280
83-340
3.2 - 7.9
NA'
0.4 - 75
11,000-140,000
15-260
120-300
12-31
1.7-2.0
2.7-3.1
NA
2.4x10* -2.7x10*
After Treatment
11.0-11.8
24-53
2500 - 4600
3.2 - 7.4
2.8-4.9
1.4-65
9,900-52,000
13-170
95-190
13-19
1.6-2.0
2.4-2.7
32-50
3.6xlO-7-lxlO-6
'NA= Not available
For this test, control samples lost 0.3 to 1.5 percent of their 45 and 60 days contained 68 and 65 mg/kg, respectively.
weight These differences are attributed to sample heterogeneity cre-
ated by variation in amounts of Chemfix additives in the
waste and variation in PCB concentrations in raw waste
entering the Chemfix process unit.
Freeze/Thaw Weathering Test
Freeze/thaw weathering tests were performed on test
cores from molded samples of treated waste from Area C
according to method TMSWC-11. Results of these tests were
reported in the same manner as those of wet/dry weathering
tests. A weight loss of less than 1 percent was found after 12
freeze/thaw cycles. Control samples lost 0.8 to 1.5 percent of
their weight. Insignificant weight loss during freeze/thaw
weathering tests indicates product durability in an exposed
environment.
PCB Dechlorination
Two sets of analyses were conducted to evaluate the
effectiveness of the Chemfix process in dechlorinating PCBs.
EPA incorporated these tests into the demonstration because
Chemfix had preliminary data suggesting such dechlorination
(Chemfix, 1987).
The first set of analyses evaluated concentrations of total
PCBs and individual PCB congeners in waste before and after
treatment Quantifying concentrations of individual congeners
provides information on relative concentrations of congeners
with high chlorine content and low chlorine content. An
increase in concentration of low-chlorine congeners with a
corresponding decrease in concentration of high-chlorine
congeners would suggest some dechlorination of the PCB
molecule.
Individual PCB homologs (mono through deca) were
determined in raw and treated soil samples aged 15, 30,45,
and 60 days. Data showed considerable variability in total
PCB content that was not related to the amount of aging. For
example, total PCBs in samples aged 15 and 30 days were
approximately 49 and 32 mg/kg, respectively. Samples aged
Concentrations of PCB homologs (mono through deca)
normalized to the hexa homolog revealed elevated concentra-
tions of di, tri, tetra, and penta homologs in treated samples
compared to those in raw waste. Marginal decreases were
found in hepta and octa homologs, although these differences
may not be significant.
In the second set of analyses, treated product was exam-
ined for by-products of complete dechlorination of PCBs.
These by-products, dihydroxy biphenyls, were not found in
any samples of treated waste. A comparison of PCB profiles
for raw and treated wastes showed excellent agreement, indi-
cating no chemical change from PCBs to another compound
as a result of treatment. The test method was confirmed by
spiking a sample of treated waste with dihydroxy biphenyls;
92 percent of the spike was recovered.
Results of these two sets of analyses suggest limited PCB
dechlorination. However, it is not known whether this appar-
ent, partial dechlorination is the result of the treatment process
or of some other phenomenon such as analytical error, bio-
degradation, or poor recovery. There was no evidence of
products of complete dechlorination. No conclusions can be
drawn at this time regarding the effectiveness of the Chemfix
process in dechlorinating PCBs.
Air Monitoring
PCB concentration in ambient air close to and downwind
of Chemfix equipment was measured with a high-volume air
sampling device. Analyses of field and trip blanks and upwind
and downwind samples revealed PCB levels equivalent to
27
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concentrations characteristic of an urban environment in the
United States (0.7 to 12 ng/m3).
Materials Balance
Table C-5 presents materials balance information for
each of the four test runs performed by Chemfix during the
demonstration. Approximately 4 to 6 tons of dry soil material
were treated for each test run. Dry reagent was added in
amounts that varied from 12 to 21 percent of the wet soil
material by weight, with an average value of 17 percent. The
amount of diluted liquid reagent added was relatively consis-
tent for each test run (20 percent of wet soil weight). Each test
run produced approximately 4 to 6 cubic yards of treated
material.
Reductions in leachable lead or copper concentrations in
treated waste may result from diluting raw waste with re-
agents used in the treatment process. Therefore, a dilution
factor and volume expansion ratio (VER) was calculated for
each test run. The dilution factor was 1.3 for Area A and 1.4
for Areas C, E, and F. Contaminated soils from the PESC site
were diluted between 30 and 40 percent and were increased in
volume between 20 and 50 percent as a result of treatment
Calculation of the VER requires an estimate of the in situ
bulk density of the raw waste; therefore, the VER is relatively
site-specific. However, the VER allows users of Chemfix
technology to roughly estimate the volume of treated waste
that would require disposal based on the quantity of raw waste
present at a site.
Table C-5. Summary of Chemfix Operating Conditions
Area A AreaC
AreaE
AreaF
Average
Total soil (screened), kg"
Total dry reagent, kg*
(ChemsetI-20)
Total liquid reagent, kg°
(water included)
(Chemset C220)
Total weight, kg
Slurry bulk density, glcn?d
Total volume, m3'
Dry reagent-to-soil ratio
Liquid reagent and water-to-soil ratio
Soil-to-total feed ratio
Operating time, minute/
Soil feed, kg/sec
Dry reagent, kglsec
Liquid reagent, kg/sec
Total feed addition, kglsec
4218
526
886
5,630
1.9
2.9
0.12
0.21
0.75
20
35
0.44
0.74
4.7
5,153
780
1.082
7,014
2.0
3.4
0.15
0.21
0.73
13
6.6
1.0
IA
9.0
5,779
1,070
1.017
7,865
1.9
4.1
0.19
0.18
0.73
19
5.1
0.94
0.89
6.9
5,434
1,143
1.027
7,604
1.6
45
0.21
0.19
0.71
16
5.7
1.2
LL
7.9
5,146
880
1.002
7,029
1.7
3.7
0.17
0.20
0.73
17
5.0
0.9
UL
6.9
• The weight of soil used was obtained from the Chemfix weight feeder totalizer.
* The weight of dry reagent added was obtainedfrom the Chemfix reagent totalizer.
e The weight of diluted liquid reagent added was based on a reading from the Chemfixflow
meter and 11.04 Iblgallon.
d Slurry bulk density was obtainedfrom laboratory analysis.
' Total volume was calculated based on total weight and bulk density.
1 The operating time was checked with a stopwatch.
28
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Appendix D
Past Applications of the Chemfix Technology
The SITE demonstration provided information on the
application of the Chemfix solidification/stabilization process
to waste from the PESC site. This appendix summarizes
additional applications of the technology to industrial wastes,
spiked electroplating wastes, Superfund wastes, and munici-
pal wastes. Information describing these applications was
supplied by Chemfix. Quality assurance of the data was not
verified.
Industrial Wastes Applications
Chemfix provided information on applications of the
solidification/stabilization process to a wide variety of indus-
trial wastes. The Chemfix process was used to solidify/stabi-
lize electroplating wastewater treatment sludge (F006) and
dissolved air flotation sludge (K048) to make those wastes
eligible for delisting from the EPA list of hazardous wastes
noted in 40 CFR 261.31 and 261.32. Electroplating waste
spiked with metals and other industrial wastes were also
successfully solidified/stabilized.
Chemfix Treatment for Delisting ofRCRA
Wastes
In September 1985, EPA delisted 150 million gallons of
dissolved air flotation sludge (K048) from the Amoco Oil
Company after chemical solidification/stabilization of the waste
with the Chemfix process. The exclusion required daily test-
ing during the treatment for lead and total chromium in the EP
toxicity test extracts to ensure that the process adequately
solidified/stabilized the material. In November 1986, EPA
delisted approximately 6.8 million gallons of electroplating
wastewater treatment sludge (F006) from General Motors
Corporation after chemical solidification/stabilization with
the Chemfix process. Table D-l presents a summary of EP
toxicity test data for these two delisting projects.
Other Industrial Wastes
The Chemfix process has been used on a wide variety of
industrial wastes. Three treatability studies provide examples
of the type of experience Chemfix has with industrial wastes:
• Chemfix treated waste stream comprised of arsenic and
hydrofluoric acid from production and purification of hy-
drofluoric acid. Arsenic leached from the raw waste in
concentrations greater than 70,000 ppm. After treatment
with the Chemfix process, arsenic leached at 2.5 mg/L,
and the volume of waste increased by less than 150 percent
• Chemfix treated electric arc furnace dust (K061) from a
U.S. Steel facility. This waste contained metals in the
following concentrations:
3,000 mg/kg total Cr,
3,000 mg/kg total Cu,
14,000 mg/kg total Pb,
70,000 mg/kg total Zn.
Concentrations of chromium and lead in the treated leachate
were less than 0.3 mg/L; data for copper and zinc were not
available. Based on results of the treatability study, EPA
proposed the waste for delisting from the list of RCRA
hazardous wastes.
• The Chemfix process was applied to a mixture of listed
waste sludges for which solidification/stabilization was
defined as best demonstrated available technology (BDAT).
Concentrations of cadmium, nickel, and lead in the TCLP
extract from the raw waste were 1.3,65.8, and 15.6 mg/L,
respectively. After Chemfix treatment, concentrations of
cadmium, nickel, and lead in the TCLP extract were less
than 0.025,015, and 0.1 mg/L, respectively.
Long-Term Analyses of Treated Industrial Waste
Chemfix supplied data on projects conducted during the
1970s that were reexamined 8 to 12 years after completion.
These data provide information on the long-term stability of
the Chemfix product (Table D-2).
In 1973, the Chemfix process was used to treat electro-
plating waste from Ranco, Inc., containing elevated concen-
trations of cadmium, chromium, and nickel. This waste was
sampled in 1985 to determine the long-term stability of the
Chemfix product Concentrations of metals in MEP extracts
were all below the limits defining a hazardous waste.
In 1975, the Chemfix process was used to solidify/stabilize
refinery wastes from the Sohio Oil Company and the Koch
Refining Company. The refinery wastes contained high con-
centrations of lead and chromium. In 1983, the treated prod-
ucts were sampled to determine leaching characteristics after
8 years of aging. Concentrations of lead and chromium in EP
toxicity test extracts were well below levels used to establish a
characteristic waste under RCRA.
Small Business Innovative Research Project
In May 1987, Chemfix completed Phase 1 of the Small
Business Innovative Research (SBIR) project for EPA. For
this study, Chemfix spiked electroplating waste (F006) with a
variety of metals and processed the waste with standard
29
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Table D-l. EP Toxicity Test Data for Detisted Wastes Solidified and Stabilized with the Chemfix Process (mg/L)
Ag As Ba Cd Cr Hg Ni Pb Se
1. Amoco Oil (K048)
(Pondl)
2. General Motors (F006)
(Impoundment #2)
EP Toxicity Standards
Drinking Water Standards
NA*
0.034
1.0
0.01
0.17
0.002
5.0
0.05
1.4
0399
100.0
1.0
0.03
0.019
1.0
0.01
0.07
0.437
5.0
0.05
0.05
<0.001
0.2
0.002
0.13
0.364
NA
NA
1.05
0.34
5.0
0.05
0.15
1
0.002
1.0
0.01
* NA = not available.
Table D-2. EP Toxicity Test Data for Industrial Wastes Solidified and Stabilized with the Chemfix Process during the
1970s (mg/L)
Ag As Ba Cd Cr Hg Ni Pb Se
1. Ranco, Inc.
2. Sohio Oil
3. Koch Refining
EP Toxicity Standards
Drinking Water Standards
<0.01
NA*
NA
1.0
0.01
<0.002
NA
NA
5.0
0.05
<0.1
NA
NA
100.0
1.0
0.032
NA
NA
1.0
0.01
0.16
0.182
NA
5.0
0.05
0.018
NA
0.07
0.2
0.002
0.16
NA
NA
NA
NA
0.12
0.24
0.32
5.0
0.05
0.016
NA
NA
1.0
0.01
*NA as not applicable.
Chemfix reagents and a variety of additives. The waste was
characterized before and after treatment by measuring ;metal
concentrations in TCLP extracts. Although this was a labora-
tory (bench-scale) study, it is a good supplement to the SITE
demonstration because it includes information on metals other
than those found at the PESC site in a different waste matrix.
Table D-3 presents results of the SBIR project. Concen-
trations of cadmium, chromium, copper, zinc, and nickel in
TCLP extracts from treated waste were 98 percent less than
concentrations in extracts from untreated wastes. The Chemfix
process produced a significant (94-percent) reduction in con-
centrations of lead in TCLP extracts. Mobility of arsenic,
barium, selenium, silver, and vanadium was unaffected by the
Chemfix process, and mobility of antimony and mercury
increased. Reported reductions do not account for dilution of
waste by addition of Chemfix reagents. Data were not avail-
able on quantities of reagents used and on volume expansion
as a result of treatment.
Spiked electroplating waste was also treated with a set of
additives to test the effectiveness of the Chemfix process
when used in conjunction with other reagents. Table D-4
summarizes results of these tests. The data indicate the fol-
lowing:
• Hexadecyl mercaptan enhanced mercury binding but had
little effect on antimony, arsenic, barium, selenium, silver,
or vanadium.
• Activated carbon was effective at binding thallium and
antimony at concentrations of 100 and 1,000 mg/kg, re-
spectively.
• Polyethylene amine at concentrations of 40,000 mg/kg
produced an 80-percent reduction in arsenic in the post-
treatment TCLP extract as compared to the pretreatment
TCLP extract. However, mobility of copper, thallium,
antimony, selenium, and mercury increased.
• Ethylenediamine tetraacetate (EDTA) successfully immo-
bilized arsenic but failed to improve containment of cad-
mium, lead, copper, thallium, and antimony.
In another part of the SBIR project, municipal waste was
spiked with organic pollutants such as pentachlorophenol
(PCP), PCBs (Aroclor 1254), and 1-chlorohexodecane. Re-
sults indicated a decrease in the concentration of Aroclor 1254
from 1,000 mg/kg on the day of Chemfix treatment to 165 mg/
kg after 15 days. The mechanism causing this decrease is
unknown.
Superfund Waste Applications
The Chemfix treatment process was tested on two differ-
ent types of contaminated soil similar to waste found at the
PESC site. The first of these tests was conducted on Super-
fund Analytical Reference Material (S ARM), a synthetic waste
developed to model a typical Superfund waste. The second
test was conducted on soil from an actual Superfund site.
The SARM Test
When Chemfix submitted an application for the SITE
program, it treated and analyzed soil produced as SARM.
Results of this analysis are presented in Table D-5. These
results confirm SBIR project results for cadmium, copper,
chromium, nickel, lead, and zinc. Concentrations of these
metals in TCLP extracts were reduced 99 percent by Chemfix
treatment
The concentration of arsenic in the TCLP extract from the
treated material was 97 percent less than that from the untreated
material. This is a significant difference from the result of the
SBIR study in which arsenic in the TCLP extract was reduced
only 22 percent. According to these tests and other treatability
studies, the ability of the Chemfix process to immobilize
arsenic varies with the matrix being treated.
30
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Table D-3. Application of Standard Chemfix Treatment Technology to Waste Spiked with Inorganic Contaminants
Metals
Cadmium
Lead
Copper
Thallium
Antimony
Arsenic
Selenium
Silver
Vanadium
Zinc
Barium
Chromium
Mercury
Nickel
Concentrations
of Spiked Sludge
inTCLP Extract
(mg/L)
34.8
3.97
235
135
050
157
0.020
0.01
<0.1
158
0.8
7.1
2.07
31.9
Concentrations
of Chemfix Product
inTCLP Extract
(mg/L)
0.072
024
0.43
12.4
2.84
1.23
0.054
0.01
05
0.265
1.1
<0.05
2.12
0.18
Percent
Reduction"
by Chemfix
Process
99.8
94.0
98.2
8.2
No Reduction11
21.7
No Reduction*
No Reductionb
No Reduction11
99.8
No Reduction1"
>99.9
No Reduction*
99.4
f • —"— — — "•"• J •**• • •""•"^v. w vj wr m*x> u J v»Ub**»«lS-*« \JJ I V-l^£l* i * \J trl H L// ffU*lHSIt- £4} l*Vl&t-H4t/tC IS ft tflC
quantity of reagents used.
* TCLP metal leachatefrom the Chemfix product was higher than leachatefrom spiked sludge.
Source: Chemfix, 1987, Demonstration of Innovative Technologies for Hazardous Waste Site Cleanup. Response to Proposal
SITE-002.
Table D-4. Application of Chemfix Treatment Technology with Assorted Additives to Spiked Electroplating Waste
Metals
Concentrations of
Spiked Sludge
inTCLP Extract
(mg/L)
Concentrations of
Chemfix Product
inTCLP Extract
(mgIL)
Concentrations in TCLP Extract
after Application of Chemfix Process with These Additives
Hexadecyl Activated Polyethylene Ethylenediamine
Mercaptan@ Carbon @ Imine @ Tetraacetate @
4,000 mg/L 1,000 mg/L 40,000 mg/L 100 mg/L
Cadmium
Lead
Copper
Thallium
Antimony
Arsenic
Selenium
Silver
Vanadium
Zinc
Barium
Chromium
Mercury
Nickel
34.8
3.97
235
135
050
157
0.020
0.01
<0.1
158
0.8
7.1
2.07
31.9
0.072
0.24
0.43
12.4
2.84
1.23
0.054
0.01
05
0.265
1.1
<0.05
2.12
0.18
0.073
0.2
0.18
75
1.43
1.68
0.41
0.7
05
0.052
0.9
<0.05
0.0015
0.19
0.043
0.35
0.40
0.32
0.49
0.08
0.3
1.22
15.8
2.81
0.33
0.71
0.03
0.052
1.4
6.9
024
0.36
0.3
0.66
12.4
4.0
0.067
Proposal Site - 002.
31
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TreataUlity Study for Superfund Soil
The Chemfix stabilization process was used to treat soil
from a Superfund site in the northeastern United States.
Metals in the soil included arsenic, cadmium, chromium,
copper, lead, nickel, and zinc. Table D-6 shows metals con-
centrations in TCLP extracts from soil before and after treat-
ment. The Chemfix stabilization process reduced these metals
concentrations by 97 to 99 percent. The total reagent addition
was less than 25 percent of the waste by weight
Municipal Sludge Applications
The Chemfix process was successfully used to stabilize
sewage sludge from the South Essex Sewerage District that
contained high levels of animal fats and metals. The treated
sludge was used as daily cover and final capping material for
sanitary landfills. From 1981 to 1984, the Chemfix treatment
process was used to stabilize 600 tons per day of municipal
sewage sludge from the Blue Plains Wastewater Treatment
Plant. A total of 240,000 tons of solidified/stabilized product
was used as supplemental capping material for Maryland
sanitary landfills.
The Chemfix process was used to treat approximately
100 tons per day of dewatered sludge from the Gloucester
County Utilities Authority. The treated sludge was used as
intermediate and final cover for a municipal sanitary landfill.
Table D-7 shows data from these three applications of the
Chemfix technology. No information on untreated sludge is
available.
Table D-5. Results of Application of Chemfix Process to SARM
Metals
Arsenic
Cadmium
Chromium
Copper
Nickel
Lead
Zinc
Concentration in TCLP
Extract From Untreated
Material
Sample 1
(mg/L)
105
28
7
175.5
215
38
530
Sample 2
(mg/L)
10
27
8
2095
21
28 '
520
Concentration in TCLP
Extract From Treated
Material
Sample 1
(mg/L)
0.384
<0.005
0.10
0.12
0.23
<0.05
0.033
Sample 2
(mg/L) -. :
0.176
<0.005
0.10
0.12
0.23
<0.05
053
Mean Percent
Reduction*
97
99
99
99
99
99
99
* These percent reductions do not account for dilution bf waste by addition of reagents. No information is available on the
quantity of reagents used.
Table D-6. Summary of Results from TreatabUity Study Involving Contaminated Soil from Superfund Site
Concentrations in the Extract (mg/L)
Metals
Before Treatment
After Treatment
As
Cd
Cr
Cu
Pb
Ni
Zn
105
28.0
7.0
176.0
38.0
215
530.0
0.29
0.28
0.07
1.76
038
0.21
5.3
Table D-7. EP Toxicity Test Data from Municipal Wastes Stabilized with the Chemfix Process (mg/L)
Ag As Ba Cd Cr Hg Ni Pb Se
1. South Essex
Sewerage District
2. Blue Plains Wastewater
Treatment Plant
3. Gloucester County
Utilities Authority
EP Toxicity Standards
Drinking Water Standards
NA*
NA
0.01
1.0
0.01
0.02
<0.002
0.005
5.0
0.05
031
0.6
0.2
100.0
1.0
0.03
<0.001
<0.005
1.0
0.01
0.12
0.013
0.08
5.0
0.05
0.003
<0.0005
0.0009
0.2
0.002
0.18
NA
NA
NA
NA
0.32
0.005
<0.05
5.0
0.05
0.01
NA
0.003
1.0
0.01
* NA = not available.
32
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