EPA
United States
Environmental Protection
Agency
Research and
Development
(MD-235)
E1PA/540/A5-89/001
May 1989
HAZCON
Solidification Process,
Douglassville, PA
Applications Analysis Fteport
SUPERFUND INNOVATIVE
TECHNOLOGY EVALUATION
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EPA/540/A5-89/001
May 1989
Applications Analysis Report
HAZCON Solidification Process,
Douglassville, Pennsylvania
Risk Reduction Engineering Laboratory
Office of Research and Development
U.S. Environmental Protection Agency
Cincinnati, OH 45268
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Notice
The information in this document has been funded by the U.S. Environmental
Protection Agency under Contract No. 68-03-3255 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
USEPA document. Mention of trade names or commercial products does not constitute
an endorsement or recommendation for use.
11
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Foreword
The Superfund innovative Technology Evaluation (SITE) program was
authorized in the 1986 Superfund amendments. The,program is a joint effort
between EPA's Office of Research and Development and office of Solid Waste
and Emergency Response. The purpose of the program is to assist the develop-
ment of hazardous waste treatment technologies necessary to implement new
cleanup standards which require greater reliance on permanent remedies.
This is accomplished through technology demonstrations which are designed
to provide engineering and cost data on selected technologies.
This project consists of an analysis of Hazcon's proprietary solidifi-
cation process. The technology demonstration took place at a former oil
reprocessing plant which comprises the Douglassville Superfund site. The
demonstration effort was directed at obtaining information on the performance
and cost of the process for use in assessments at other sites. Documentation
consists of two reports. The Technology Evaluation Report (EPA 540/5-89/00la)
describes the field activities and laboratory results. This Applications
Analysis provides an interpretation of available data and discusses the
potential applicability of the technology.
Additional copies of this report may be obtained at no charges from
EPA's Center for Environmental Research Information, 26 West Martin Luther
King Drive, Cincinnati, Ohio, 45268, using the EPA document number found on
the report's front cover. Once this supply is exhausted, copies can be
purchased from the National Technical Information Service, Ravensworth
Bldg., Springfield, VA, 22161, (702) 487-4600. Reference copies will be
available at EPA libraries in their Hazardous Waste Collection. YOU can
also 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.
Margaret M. Kelly, olrecto'r
Technology staff, office of
Program Management and
Technology, OSWER
[fred W1. Lindsay, Actiig Director
Office of Environmental Engineering
and Technology Demonstration
111
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Tables
Number Page
1 Comparison of HAZCON Results to Some Regulatory Values
for Metals ; 15
2 Estimated Cost 20
B-l Wastes Compatible with the HAZCON System 30
B-2 Priority Pollutant Limits in TCLP Extracts 32
C-l Physical Properties of Untreated Soils 36
C-2 Physical Properties of Treated Soils 37
C-3 Migration Potential 38
C-4 Chemical Analyses of Untreated Soils 39
C-5 Chemical Analyses of Treated Soils 39
C-6 Concentration of Metals in TCLP Leachates 40
C-7 Volatiles in TCLP Leachates 41
C-8 Base Neutral/Acid Extractable in TCLP Leachates 41
Figure
A-l HAZCON process flow diagram 27
VI
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Contents
Page
Foreword iii
Abstract iv
Tables vi
Figure vi
Abbreviations and Symbols , vii
Acknowledgment x
1. Executive Summary 1
2. Introduction 5
The SITE Program 5
SITE Program Reports 5
Key Contacts '. 6
3. Technology Applications Analysis 7
Introduction 7
Conclusions 7
Technology Evaluation 8
Environmental Regulations and the HAZCON Results 12
Waste Characteristics and Performance of the Technology 14
Ranges of SITE Characteristics Suitable for the Technology 15
Material Handling Required by the Demonstrated Technology 16
Personnel Issues 17
Testing Procedures : 17
4. Economic Analysis 19
Introduction 19
Results of Economic Analysis 21
Basis of Economic Analysis 21
References 25
Appendices
A. Process Description 27
B. Vendor's Claims for the Technology 29
C. SITE Demonstration Results 35
D. Case Studies 43
References for Appendices 52
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Abstract
This document is an evaluation of the HAZCON solidification technology and its
applicability as an on-site treatment method for waste site cleanup.
A Demonstration was held at the Douglassville, Pennsylvania Superfund site in the
fall of 1987. Operational data and sampling and analysis information were carefully
monitored and controlled to establish a data base against which other available data
and the vendor's claims for the technology could be compared and evaluated.
Conclusions were reached concerning the technology's suitability for use in clean up of
the types of materials found at the test site, and extrapolations were made to cleanups
of other materials.
Site materials were sampled to characterize the site. Untreated feedstock materials
were sampled to provide a base case against which to compare the product materials,
and solidified materials were sampled after 7 days and after 28 days of curing. The
samples were analyzed to determine physical properties such as unconfined
compressive strength and permeability, chemical properties such as leachability, and
microstructural characteristics. The results of these tests were then considered, along
with those obtained by other investigators, and conclusions on the technology drawn
from all the work.
The conclusions drawn from the test results and other available data are that: (1) the
process can solidify wastes high in organics; (2) the process does not immobilize
volatile and semivolatile organics in most instances; (3) heavy metals are successfully
immobilized; (4) a large volume increase can be expected where moisture content of
the wastes is low; (5) the solidified material shows good structure with high
unconfined compressive strengths and low permeabilities; (6) the microstructure
indicates a potential for degradation over the long term; and (7) the process is
economical.
IV
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Abbreviations and Symbols
ANS 16.1
API
ARAR
ASTM
BOAT
BNA
CERCLA
CFR
cm/sec
cuft
cuyd
DSA
EPA
EPTox
FSA
g/ml
HSWA
KPa
Kw
LAN
LAS
Ib/min
LFA
m/sec
MCC-1P
MFU
mg/kg
Modified American Nuclear Industry leaching test method
American Petroleum Institute
Applicable or Relevant and Appropriate Requirements
American Society for Testing and Materials
Best Demonstrated Available Technology
base neutral/acid (extractable)
Comprehensive Environmental Response, Compensation, and
Liability Act of 1980
Code of Federal Regulations
centimeters per second
cubic feet
cubic yard
Drum Storage Area
Environmental Protection Agency
Extraction Procedure Toxicity Test - leach test
Filter Sludge Area
grams per milliliter
Hazardous and Solid Waste Amendments to RCRA - 1984
kilopascal (s)
kilowatt(s)
Lagoon North
Lagoon South
pounds per minute
Landfarm Area
meters per second
Materials Characterization Center static leach test method
Mobile Field Blending Unit
milligrams per kilogram
Vll
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Abbreviations and Symbols (Continued)
mg/l
ml/g
NCP
n/m
NPDES
NPL
O&G
ORD
OSHA
OSWER
PADER
PAHs
Pb
PCBs
POP
PFA
PL
ppb
ppm
psi
RCRA
RI/FS
RREL
SARA
SEM
SITE
SPCC
TCLP
TOG
TSCA
UCS
milligrams per liter
milliliters per gram
National Contingency Plan
Newtons per meter
National Pollutant Discharge Elimination System
National Priorities List
oil and grease
Office of Research and Development
Occupational Safety and Health Act
Office of Solid Waste and Emergency Response
Pennsylvania Department of Emergency Response
polycyclic aromatic hydrocarbons
lead
polychlorinated biphenyls
pentachlorophenol
Processing Facility Area
Public Law
parts per billion
perts per million
pounds per square inch
Resource Conservation and Recovery Act of 1976
Remedial Investigation/Feasibility Study
Risk Reduction Engineering Laboratory
Superfund Amendments and Reauthorization Act of 1986
Scanning Electron Microscope
Superfund Innovative Technology Evaluation Program
Spill Prevention, Control, and Countermeasure Plan
Toxicity Characteristic Leaching Procedure
total organic carbon
Toxic Substances Control Act of 1976
unconfined compressive strength
vui
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Abbreviations and Symbols (Continued)
11/1
voc
WES
micron(s)
micrograms per liter
volatile organic compound
Waterways Experiment Station (Army Corps of Engineers)
IX
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Acknowledgments
This report was prepared under the direction and coordination of Paul R. dePercin,
EPA SITE Program Manager in the Risk Reduction Engineering Laboratory,
Cincinnati, Ohio. Contributors and reviewer for this report were Dick Valentinetti,
John Kingscott and Linda Galer of USEPA, Washington, D.C.; Stephen James, Robert
Olexsey, Ronald D. Hill, and Lisa Moore of USEPA, RREL, Cincinnati, Ohio; and
Timothy Smith of HAZCON Inc., Katy, Texas.
This report was prepared for EPA's Superfund Innovative Technology Evaluation
(SITE) Program by Stephen Sawyer of Foster Wheeler Enviresponse, Inc. for the U.S.
Environmental Protection Agency under Contract No. 68-03-3255.
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Section 1
Executive Summary
Introduction
The HAZCON solidification process was tested and
evaluated under the Superfund Innovative
Technology Evaluation (SITE) Program. The process
involves the mixing of hazardous waste material and
cement with a patented nontoxic chemical called
Chloranan. Chloranan is claimed to neutralize the
inhibiting effects that organic contaminants
normally have on the hydration of cement-based
materials. HAZCON claims that the wastes are
immobilized and bound by encapsulation into a
hardened leach-resistant concrete-like mass by this
process. Therefore, the major objectives of the SITE
project were to evaluate' the HAZCON solidification
technology in the following areas:
Effectiveness for treating and solidifying
contaminated soils varying from 1% to 25% by
wt oil and grease during the Demonstration
Test and other types of waste high in organics.
Ability to immobilize the site contaminants,
which included volatile organics (VOCs), base
neutral/acid extractables (BNAs), oil and
grease, polychlorinated biphenyls (PCBs), and
heavy metals.
Probable long-term stability and integrity of
the solidified soil.
Performance and reliability of the process
system.
Costs for commercial-scale applications.
Conclusions
The conclusions drawn from reviewing the data on
the HAZCON process, both from the SITE
Demonstration, where the most extensive results
were obtained, and the literature, in relation to SITE
Program objectives, are:
The process can solidify contaminated material
high in organics. Soils at the Douglassville
Superfund site with up to 25% organics were
solidified. Other applications showed
successful solidification of petroleum refinery
waste streams, and other wastes high in
organics.
Heavy metals were immobilized with leachate
reductions in excess of a factor of 100 in many
instances.
Organic contaminants, VOC and BNA, were
not immobilized for the most part. Instances
where immobilization of organics occurred were
observed in some studies outside the SITE
Program. In the SITE Program the Toxicity
Characteristic Leaching Procedure (TCLP)
produced equivalent leachate concentrations
for the treated and untreated wastes.
The physical properties of the treated wastes
were in general quite satisfactory. High
unconfined compressive strength (UCS), low
permeabilities, and satisfactory results of
weathering tests were obtained. However, large
volume increases in treated soils were found.
The microstructural analyses of the solidified
soil materials indicate a potential for long-term
durability problems, although a prediction on
solidified mass durability is not possible.
Efficient operating capabilities of the
equipment are attainable, even though
numerous operating difficulties were
encountered by HAZCON during the SITE
Demonstration. It is likely that design changes
in the raw material feed system and in the
blender, the two areas where shortcomings
were observed, can improve operations.
The HAZCON system is economical. Costs will
approach $100/ton of contaminated soil when
using larger units and reduced additive
consumption within the defined parameters
(see Section 4).
Applications for immobilization of heavy metals in
wastes containing high organics, even at organic
levels higher than those of the SITE project, are
likely. Immobilization of organic contaminants in
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most applications is unlikely; some select
applications may exist, and for each a treatability
study should be performed. Where solidification of
high organic content wastes is the primary concern
satisfactory physical properties are expected.
Several moisture-related limitations must be.
considered in application of the HAZCON
technology. For wastes with low moisture contents,
such as soils, the large volume increases may require
the capability to relocate the treated material so as
not to adversely affect site contours and access. For
areas where the solidified blocks become water-
saturated, weathering cycles, particularly
freeze/thaw, may become detrimental to the highly
porous treated blocks; they could fracture due to
freezing of absorbed water."
In summary, the HAZCON technology has
applications for the immobilization of heavy metals
in soils and sludges where organics levels are high.In
addition, the remediation site should 1) contain
organic toxins that are either sufficiently immobile
or proven by a treatability study to be immobilized
and 2) be such that physical soil solidification is
desirable.
Results
Physical Tests
The most extensive physical testing on the HAZCON
process was performed as part of the SITE
Demonstration, although additional data was
obtained by Environment Canada [1], by Waterways
Experiment Station (WES) [2], and at tests at the
Sand Springs, OK Superfund site [3]. The key
physical tests, which are used in evaluating
potential treated soil durability, are unconfined
compressive strength (UCS), weathering (wet/dry
and freeze/thaw), permeability, and bulk density.
The UCS values for HAZCON-treated soil ranged
from 220 psi for the Filter Storage Cake Area (FSA)
samples during the SITE Demonstration to 2,959 psi
in the Environment Canada study on a metal
finishing sludge. These are very satisfactory when
compared to the EPA guideline of 50 psi [4] for
stabilization/solidification systems and other
concrete-based waste treatment systems, with
results typically in the range of 15 to 150 psi [5].
The results from the 12-cycle wet/dry and
freeze/thaw weathering tests showed low absolute
weight losses, less than 1.0% by wt in all cases. When
compared to control samples, the weight losses were
less than 0.3%, which is considered very low. UCS
tests after the weathering tests on the SITE
Demonstration samples showed no loss of strength.
These weathering tests are more severe than
weathering under an actual field environment,
but due to the limited number of cycles involved,
they provide indications of only short-term
durability. Quantification of solidified mass
integrity in terms of life expectancy is not possible.
Permeability is a measure of a solid's ability to
permit the passage of water. The treated soil values
obtained for the SITE Demonstration and from
Environment Canada were very low, about 10-8
cm/sec; while at Sand Springs the value was 10-6
cm/sec. This relates very satisfactorily to the target
value of 10-7 cm/sec or less used for designing soil
barrier liners for hazardous waste landfill sites. Low
permeabilities should reduce both erosion and
leaching potentials.
Bulk density results were obtained for the SITE
Demonstration and Environment Canada work,
where detailed information was available on the
wastes and on the material balances. The bulk
density changes upon solidification were relatively
small, producing large volume increases, averaging
120% during the Demonstration Test. Therefore, for
relatively dry wastes, particularly in difficult
applications where large quantities of cement and
Chloranan may be used, volume increases of 100% or
more may occur. HAZCON can reduce the volume
increases by optimizing the quantity of additives, but
this may alter the physical and chemical properties
of the treated soil.
The microstructual analyses performed on SITE
Demonstration samples included optical and
scanning electron microscopy and x-ray diffraction
analysis of the crystalline structures. These results
showed a porous and incompletely hydrated matrix
with undispersed brownish aggregates. These
shortcomings may be due in part to insufficient
mixing, which could be corrected with a more
vigorous mixer. Therefore, a long-term potential for
treated soil degradation exists, although a time
frame for degradation cannot be predicted.
Solidification occurred for all wastes reported in the
various references on the HAZCON technology, even
those high in organics and moisture.
Chemical Tests
Chemical analyses were performed on untreated and
treated waste, along with corresponding TCLP
leachate analyses. Although extensive leachate
analyses exist on treated soil, only limited data is
available on the original untreated wastes, and a
primary goal of this evaluation is to compare
contaminant mobility of treated waste versus raw
waste.
The HAZCON process is effective in immobilizing
heavy metals, and it is expected that applicable
regulations will be met. A reduction factor of over
100 for lead, the predominant metal at the site, as
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well as for zinc, was seen during the SITE
Demonstration. TCLP leachate levels for treated soil
were about 100 ug/1. The WES results for treated
Basin F liquid at Rocky Mountain Arsenal
(untreated copper content, 5,680 mg/1) using the
Extraction Procedure Toxicity (EP Tox) leach test
showed a value of 410 ug/1 in the leachate.
A significant amount of data is available from eight
sources, in varying degrees of detail, on the
immobilization of organics. In most cases, the results
show the extracts from the TCLP leaching tests of
untreated soil to be equal to those of treated soil.
However, some TCLP data, particularly that
prepared for the American Petroleum Institute (API)
[5] on petroleum refinery wastes, showed sharp
reductions in leachate concentration after waste
treatment. This indicates that there may be select
applications where immobilization of organics
occurs.
TCLP analyses during the Demonstration were
performed for VOCs and BNAs. The results for total
VOC of untreated and treated soils were below 1.0
mg/1 for soil concentrations up to 150 ppm by wt. For
BNA, the untreated and treated leachate values for
the most contaminated location, FSA, were both
about 3.0 mg/1, comprising almost exclusively
phenols. The other BNAs, phthalates and
naphthalene, were found to leach only slightly
(<100 ug/1) from both untreated and treated soils.
The results of leach tests MCC-1P and ANS 16.1,
where the core sample is left intact (not crushed like
TCLP), provided leachate values of the same order of
magnitude as the TCLP results, with ANS 16.1 less
thanMCC-lP.
The results reported by WES [2] indicate that 86.7%
of the organics were leached after five cycles of a
sequential leach test where the treated material is
crushed (similar to the TCLP test). The conclusion of
this report was that the HAZCON process did not
effectively stabilize the total organic carbon in Basin
F liquid. Other reports, by Environment Canada and
HAZCON confidential report B [6], showed similar
results.
However, the API report [5] on treating refinery
wastes showed TCLP leachate reductions for treated
waste up to 99%. Also the tests performed at Sand
Springs, OK showed TCLP leachate concentration
reductions, although all valutss were very close to
detection limits.
Economics
The economic analyses was based upon the HAZCON
10 cu yd/hr mobile field blending unit (MFU) utilized
at Douglassville under the SITE Demonstration Test
conditions. Then a range of potential operating costs
was determined assuming system improvements of a
larger unit and lower chemical consumptions,
reasonable assumptions for future units. The
analyses, based upon remediating part of the
Douglassville, PA Superfund site, considered two on-
stream factors (70% and 90%), two chemical additive
rates (the SITE Demonstration level and two-thirds
of that), and operating capacities of 300 and 2,300
Ib/min. The cost to process the feedstock, with all the
site-specific assumptions defined in Section 4 of this
report, ranged from $97 to $206/ton of soil. The lower
value is based upon reduced additive consumption
and a new and larger processing unit than the one
utilized for the SITE Demonstration.
The process is very intensive in labor and chemical
additives, with these items amounting to about 85%
to 90% of the total reported costs.
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Section 2
Introduction
The SITE Program
In 1986, the EPA's Office of Solid Waste and
Emergency Response (OSWER) and Office of
Research and Development (ORD) established the
Superfund Innovative Technology Evaluation (SITE)
Program to promote the development and use of
innovative technologies to clean up Superfund sites
across the country. Now in its third year, SITE is
helping to provide the treatment technologies
necessary to implement new federal and state
cleanup standards aimed at permanent remedies,
rather than quick fixes. The SITE Program is
composed of three major elements: the
Demonstration Program, the Emerging Technologies
Program, and the Measurement and Monitoring
Technologies Program.
The major focus has been on the Demonstration
Program, which is designed to provide engineering
and cost data on selected technologies. To date, the
demonstration projects have not involved funding for
technology developers. EPA and developers
participating in the program share the cost of the
demonstration. Developers are responsible for
demonstrating their innovative systems at chosen
sites, usually Superfund sites. EPA is responsible for
sampling, analyzing, and evaluating all test results.
The result is an assessment of the technology's
performance, reliability, and cost. This information
will be used in conjunction with other data to select
the most appropriate technologies for the cleanup of
Superfund sites.
Developers of innovative technologies apply to the
Demonstration Program by responding to EPA's
annual solicitation. EPA also will accept proposals at
any time when a developer has a treatment project
scheduled with Superfund waste. To qualify for the
program, a new technology must be at the pilot or
full scale and offer some advantage over existing
technologies. Mobile technologies are of particular
interest to EPA.
Once EPA has accepted a proposal, EPA and the
developer work with the EPA regional offices and
state agencies to identify a site containing wastes
suitable for testing the capabilities of the technology.
EPA prepares a detailed sampling and analysis plan
designed to thoroughly evaluate the technology and
to ensure that the resulting data are reliable. The
duration of a demonstration varies from a few days to
several months, depending on Ithe length of time and
quantity of waste needed to assess the technology.
After the completion of a technology demonstration,
EPA prepares two reports, which are explained in
more detail below. Ultimately, the Demonstration
Program leads to an analysis of the technology's
overall applicability to Superfund problems.
The second principal element of the SITE Program is
the Emerging Technologies Program, which fosters
the further investigation and development of
treatment technologies that are still at the
laboratory scale. Successful validation of these
technologies could lead to the development of a
system ready for field demonstration. The third
component of the SITE Program, the Measurement
and Monitoring Technologies program, provides
assistance in the development and demonstration of
innovative technologies to better characterize
Superfund sites.
SITE Program Reports
The analysis of technologies participating in the
Demonstration Program is contained in two
documents, the Technology Evaluation Report and
the Applications Analysis Report. The Technology
Evaluation Report contains a comprehensive
description of the demonstration sponsored by the
SITE program and its results,. This report gives a
detailed description of the technology, the site and
waste used for the demonstration, sampling and
analysis during the test, and the data generated.
The purpose of the Applications Analysis Report is to
estimate the Superfund applications and costs of a
technology based on all available data. This report
compiles and summarizes the results of the SITE
demonstration, the vendor's design and test data,
and other laboratory and field applications of the
technology. It discusses the advantages,
disadvantages, and limitations of the technology.
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Costs of the technology for different applications are
estimated based on available data on pilot- and full-
scale applications. The report discusses the factors,
such as site and waste characteristics, that have a
major impact on costs and performance.
The amount of available data for the evaluation of ah
innovative technology varies widely. Data may be
limited to laboratory tests on synthetic wastes, or
may include performance data on actual wastes
treated at the pilot or full scale. In addition, there are
limits to conclusions regarding Superfund
applications that can be drawn from a single field
demonstration. A successful field demonstration does
not necessarily assure that a technology will be
widely applicable or fully developed to the
commercial scale. The Applications Analysis
attempts to synthesize whatever information is
available and draw reasonable conclusions. This
document will be very useful to those considering the
technology for Superfund cleanups and represents a
critical step in the development and
commercialization of the treatment technology.
Key Contacts
For more information on the demonstration of the
HAZCON technology, please contact:
1. Regional contact concerning the Douglassville, PA
site:
Mr. Victor Janosik
Superfund Branch (3HW21)
USEPA, Region III
841 Chestnut St.
Philadelphia, PA 19107
215-597-8996
2. EPA project manager concerning the SITE
demonstration:
Mr. Paul de Percin
USEPA
Risk Reduction Engineering Laboratory
26 W. Martin Luther King Drive
Cincinnati, OH 45268
513-569-7797
3. Vendor concerning the process:
HAZCON Engineering, Inc.
Mr. Timothy Smith
P.O. Box 1247
32522 McAllister Rd.
Brookshire.TX 77423
713-934-4500
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Section 3
Technology Applications Analysis
Introduction
This section of the report addresses the applicability
of the HAZCON process to varying potential
feedstocks based upon the results obtained from the
SITE Demonstration and other HAZCON
applications test data. Since the results of the
Demonstration provide the most extensive data base,
conclusions on the technology's effectiveness and its
applicability to other potential cleanups will be
strongly influenced by those results, which are
presented in detail in the Technology Evaluation
Report. Additional information on the HAZCON
technology, including a process description, vendor
claims, a summary of the Demonstration Results,
and reports on outside sources of data using the
HAZCON technology are provided in Appendices A-
D.
Following are the overall conclusions being drawn on
the HAZCON technology. The Technology
Evaluation subsection discusses the available data
from the Demonstration, HAZCON, and the
literature, and provides more details on the
conclusions and applicability of the HAZCON
process.
Conclusions
The conclusions drawn from reviewing the data on
the HAZCON process are:
The process can solidify contaminated material
high in organics. Soils at the Douglassville
Superfund site with up to 25% organics were
solidified. Other applications showed successful
solidification of petroleum refinery waste
streams, organics, water high in organics from
a waste storage pond, metal finishing sludge,
and other less clearly defined wastes.
Immobilization of heavy metals was observed,
with leachate improvements for lead and zinc in
excess of a factor of 100.
Organic contaminants, VOCs and BNAs, were
not immobilized for the most part. The
extensive testing for the Demonstration and
other test programs showed no immobilization
of the organics. However, there were two
instances where immobilization of organics
occurred.
The physical properties of the treated wastes
are in general quite satisfactory. High UCS,
low permeabilities, and satisfactory results of
weathering tests were obtained. However, large
volume increases in treated soils can be
expected, and the microstructural analyses of
the solidified soil materials indicates a
potential for long-term durability problems.
Application for immobilization: of heavy metals (up
to 2.3% by wt) in wastes containing high organics, up
to at least 25% by wt in soils, has been shown.
Successful immobilization of higher quantities of
heavy metals at even higher oil and grease levels
would be anticipated. Immobilization of VOCs and
BNAs did not occur in the SITE Demonstration test
on soils up to 25% by wt oil and grease,and
immobilization of other organics, as reported by
other investigators, was also unsuccessful. However,
immobilization of some petroleum refinery wastes
was successful.
Therefore, applications for immobilizing organic
contaminants, compared to a simple solidification
process with only cementitious materials, may have
to be tested on a site-by-site basis to prove
applicability of the HAZCON process. For high
organies content wastes, solidification may be very
difficult; the use of Chloranan will enhance
solidification of organics.
Two limitations in the application of the HAZCON
process need to be considered. For the treatment of
soils or other relatively low-moisture wastes, the
large volume increases may limit application to
spacious areas where the excess volume of material
can be located without adversely affecting site
contours and accessibility. In addition, in very wet
areas, especially below the water table, where the
solidified material would become saturated,
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weathering cycles could lead to fractures in the
highly porous solidified mass of treated soil.
Technology Evaluation
The two criteria defined in the SITE Program
Demonstration Plan [7] to evaluate the HAZCON
technology are:
Mobility of the contaminants as determined
from leaching and permeability tests, and
Integrity of the solidified soil as determined
from various physical tests such as UCS,
weathering (wet/dry and freeze/thaw), and
microstructural analyses (microscopy and x-ray
diffraction).
The following discussions utilize the available
HAZCON information to provide more detailed
conclusions on the process, particularly as related to
the various physical and chemical properties of
treated material. The reader should note that the
results differ from the claims expressed by HAZCON
in Appendix B in some instances. ~
Physical Test Results
The most extensive physical testing on the HAZCON
process was performed in the SITE Project and
reported in detail in the SITE Technology
Evaluation Report [8]. Additional data.as defined in
Appendix D, was provided by Environment Canada
[1], by Waterways Experiment Station (WES) on the
laboratory investigation they performed on Basin F
fluid wastes at Rocky Mountain Arsenal [2], and for
tests at the Sand Springs Superfund site [3] near
Tulsa, Oklahoma. This limited quantity of data, both
physical and chemical, is not unexpected, since the
purpose of the SITE Program is to evaluate new
innovative processes. *
Unconfined compressive strength is a primary
indicator of the durability of solidified wastes. The
results of the studies show very satisfactory
strengths for the solidified wastes relative to EPA's
guideline of 50 psi [4] for stabilization/solidification
systems. The Demonstration Test results for 28-day
samples ranged from 219 psi at FSA to 1,574 at PFA.
An inverse relation exists between strength and oil
and grease content, although samples with the
lowest oil and grease content, at DSA, did not give
the highest UCS. If the inverse relationship of UCS
to oil and grease continues at higher concentration
levels, then high organic content wastes (>25% by
wt) may produce solids approaching the 50 psi
guideline.
The values obtained at Sand Springs averaged 530
psi for an undefined formulation. For the
Environment Canada laboratory study, with the
same ratio of waste to cement to Chloranan as at the
SITE project, the UCS was 2,959 psi. The value
reported in the WES study was 2,902 psi. The latter
three studies did not involve contaminated soils, and
all involved higher water content waste than the
SITE test material.
SITE Demonstration UCS values at 7 and 28 days
were essentially equal. For the formulation tests on
samples prepared in the laboratory without
Chloranan, the UCS increased about 40% between
the 7- and 28-day samples, which is an expected
increase for Type I cement. A possible explanation is
that Chloranan accelerated the cement setting
reactions. The laboratory formulations for FSA
showed UCS values below 40 psi; thus, the
Chloranan addition in the field tests, as seen above,
had a very positive effect on UCS. No apparent effect
on strength was seen for soil from LAN. This
suggests that the Chloranan's contribution to UCS
starts to occur above 16.5% by wt oil and grease and
below 25% by wt oil and grease in the untreated soil.
These are all very satisfactory results, especially
compared to the EPA guideline of 50 psi for
stabilization/solidification systems. High UCS
values imply the potential for maintaining
structural integrity for many years. Other cement-
based waste treatment systems are typically in the
range of 15 psi to 150 psi [5], although the
comparison may not be fair since the weight ratio of
waste to cement varies widely in these processes.
Weathering effects can break down the internal
structure of the solidified soil producing potential
paths for water flow, which would increase
permeability and the potential for contaminant
leaching. Twelve-cycle wet/dry and freeze/thaw tests
performed during the SITE Demonstration produced
good results, in which the weight loss of the test
specimens was only slightly greater than their
corresponding controls (0.98% vs. 0.84% for the
wet/dry and 1.10% vs. 0.80% for the freeze/thaw).
Four-cycle wet/dry tests at Sand Springs [3] showed
losses of about 0.10%, which is very low. In addition,
a 12-cycle freeze/thaw test performed as part of the
Environment Canada study showed the test
specimen weight loss to be less than that of the
control. These tests, which are more severe than
conditions in the field, provide an indication of short-
term treated soil integrity under natural weathering
stresses. The tests are recommended as a means of
comparing weathering performance of different
processes, but cannot be used to predict long-term
durability.
Freeze/thaw weathering is of concern because of the
recognized potential for frost damage of concrete
structures. The test uses a greater rate of cooling
than the maximum of about 5°F per hour that is
-------
expected in nature. In addition, the tests are carried
out on specimens that are nearly water saturated,
where the water can rapidly freeze and cause
fracturing of the solidified waste. Relatively dry
concrete, below 80% of saturation level, is less likely
to fracture than a saturated material.
Unconfined compressive strength tests were
performed on both the test specimen and control
samples after the 12 weathering cycles during the
SITE Demonstration. These UCS results were
comparable to the unweathered values. Thus, it can
be concluded from the weight loss and UCS values
that the HAZCON treated soil maintained its
integrity through an initial set of weathering cycles.
A scheduled long-term monitoring program exists
during which the treated soil blocks will be sampled
annually. This will provide additional information
on durability of the solidified mass.
Permeability indicates the degree to which the
material permits or prohibits the passage of water
and is thus one measure of the potential for
contaminants to be released to the environment. It is
dependent on the solidified material's density,
degree of saturation, particle size distribution [5]; as
well as pore size, void ratio, interconnecting
channels, and the liquid pressure. Results for
permeabilities of solidified wastes are reported in the
Technology Evaluation Report [8], by Environment
Canada [5], and from the Sand Springs [3] tests. The
first two sources indicated permeabilities in the
range of 10-8 fco 10-9 cm/sec, while the latter test
value was 10-6 cm/sec. These permeabilities are a
major improvement compared to untreated soils, for
which values for the Demonstration Test were about
10-2 cm/sec. Cement systems usually can attain
permeabilities of 10-5 to 10-6 cm/sec [14], and soil
barrier liners for landfills are considered satisfactory
by EPA and the hazardous waste disposal industry if
the permeability is 10-7 cm/sec or less.
The permeabilities performed during the SITE
project laboratory formulation work showed that the
solidified sample values for LAN may have been
greater and those for FSA were about the same as
the field samples. Therefore, Chloranan may have a
beneficial effect on permeability, but insufficient
data exists to confirm it. The permeability values
measured in each study were quite low, conforming
well with HAZCON's claims, and should prove
satisfactory for any site remediation.
Bulk densities on the treated soils were measured
during the Demonstration, by Environment Canada
on a metal finishing waste containing 50% moisture,
and on an oily sludge material high in moisture
content provided to HAZCON.
The bulk density increase of the raw residue from the
Environment Canada study after treatment was
23.5% (from 1.49 g/ml to 1.84 g/ml) for a weight
increase from the addition of water, cement, and
Chloranan of 126%. Therefore, the calculated volume
increase of the treated residue, compared to the
untreated wet residue, was 83%. This compares to an
average volume increase for the relatively dry soils
tested during the Demonstration of 120%. For an oily
sludge, the volume upon solidification decreased, but
information on quantities of additives used,
composition of the waste, UCS, or other physical
properties of this solidified material is not available.
These results deviate from the claim of HAZCON
that the volume change upon remediation is very
small.
HAZCON claims that with optimization of the
quantities of cement and Chloranan used (reductions
from SITE project quantities of 33% to 66%), the
volume increase could be reduced. However, other
physical and chemical properties of the treated soil
may change with these reductions. It is projected
that the minimum volume increase on the
Douglassville soils would be 40% to 50% and less for
the waste treated by Environment Canada. It has
been verbally indicated by HAZCON that wastes
high in moisture will have a smaller volume
increase. It appears from the Demonstration Test
laboratory formulation data that the addition of
Chloranan resulted in a small increase in the bulk
density of the treated soil. However, more data is
required to confirm this observation.
In conclusion, it appears that for relatively dry waste
materials, bulk density changes are small and the
resultant volume increases are large. This could be a
very important remediation design consideration at
many sites
Optical microscopy, scanning electron microscopy,
and x-ray diffraction analyses were performed on
untreated and treated soil samples during the SITE
Demonstration. These methods are commonly used
techniques for understanding; the mechanisms of
structural degradation of soil, cement, and soil-
cement mixtures both with and without addition of
inorganic and organic compounds. Although
relatively few studies of the microstructure of
complex waste/soil mixtures like those resulting
from stabilization/solidification procedures have
been reported, useful information can be obtained on
the potential durability of the solidified mass. These
observations complement the weathering test
results, which are short-term measures of solidified
mass integrity; and UCS which is an indirect
indication of durability.
Microstructural studies from the Demonstration can
provide information on the potential for structural
change over the long-term, although quantitative
predictions on durability are not possible. Results
-------
described in this report suggest that the HAZCON-
solidified material may have a gerater potential for
long-term degradation than ordinary Portland
cement concrete. The HAZCON-solidified blocks
were found to be porous and incompletely hydrated,
and brownish aggregates in the soil passed through
the process unaltered. These observations are
indicative that mixing in the HAZCON MFU was
not highly efficient. It also was concluded that
encapsulation was the principal mechanism of
solidification/stabilization. This was supported by
the observation of brownish aggregates that passed
through the soil even after treatment unchanged.
Peaks in the x-ray diffraction patterns common to
both the soil and cores could not be identified with
any expected soil or cement minerals and are likely
to be associated with the (possibly unaltered) waste.
Pore concentrations and their distribution can affect
both permeability and leaching; connected pores
provide pathways for water migration. Studies have
shown that although pores of freshly prepared waste
forms are normally not saturated, upon contact with
water the matrices tend to absorb water and reach
saturation [9]. Cement-based systems with high
porosity, therefore, may lose integrity as a result of
fracturing caused by freeze/thaw or wet/dry
conditions.
Chemical Test Results
The most extensive chemical analyses, measuring
both the waste feed and leachate compositions, were
performed as part of the SITE project. Considerable
data is also available on the HAZCON technology
from many other sources, which includes those
referred to at the beginning of the physical test
section and in the IWC report [10], in two
independent confidential studies [6,11], and in a
report by Risk Science International for the
American Petroleum Institute (API) [12]. These
results are not consistent with one another, and in
many cases, information on waste properties,
additive mix quantities, and physical properties of
the treated waste are not reported. It is important to
know the quantity of the contaminants in the
untreated and treated wastes when performing a
leach, test, and this information is available in only a
few of the test programs. Leaching tests indicate the
chemical stability of the solidified mass, its tendency
[13] to leaching by water, and the mobility of
contaminants contained in the solidified waste when
they are in contact with aqueous solutions.
The HAZCON process is very effective in
immobilizing heavy metals. Reductions in leachate
concentrations by a factor in excess of 100 were
observed for many of the samples collected during
the Demonstration. At FSA, the untreated soil's oil
and grease level was 25% by wt with a lead content of
22,600 mg/kg. The leachate of the untreated soil
contained 17.9 mg/1 of lead, with the 28-day core
samples less than 400 ug/1 and the 7-day samples, 70
ug/1. Larger leachate concentration changes were
noted at other Douglassville plant areas. The WES
analyses at Rocky Mountain Arsenal show a low
value (0.41 mg/1) of copper in the treated waste TCLP
leachate for a Basin F liquid containing 5,680 mg/1
copper. HAZCON confidential report "A" [11]
(undefined waste and treatment process) for TCLP
leachates of a treated waste after 28 days of curing
shows values for chromium, cadmium, and nickel of
less than 50 ug/1 and for arsenic of less than 1.0 mg/1.
These values, with the possible exception of arsenic,
would probably meet most regulatory requirements.
For the WES work and HAZCON confidential
studies, concentrations in untreated waste extracts
were not performed, so the degree of immobilization
cannot be defined.
A significant amount of data is available on the
HAZCON technology's ability to immobilize
organics, VOCs, and BNAs. This data shows
immobilization of organics in a few instances but not
in most. In many cases only posttreatment TCLP
leachate analyses are available. The most extensive
data was accumulated for the Demonstration Test,
with soil analyses before and after solidification
matched to leachate concentrations. Three different
leach tests were performed: TCLP, ANS 16.1, and
MCC-1P. In the TCLP test, the solidified samples are
crushed, while for the other two the solid is
maintained intact. Since many test parameters differ
between leach test procedures, and experience with
MCC-1P and ANS 16.1 is limited for hazardous
wastes, the significance of any differences between
leach test results is unclear, but indications of
leachability can be discerned.
The results of the TCLP tests performed during the
Demonstration Test showed that the VOCs and
BNAs were not immobilized. Calculations of
migration potential, which is weight of a specified
analyte in the leachate divided by its weight in the
soil, were approximately equal for treated and
untreated soils. The total VOC values were
moderately low, less than 1.0 mg/1, for soil
concentrations up to 150 ppm by wt in the untreated
soil. Leachate analyses for the BNA for both treated
and untreated soils showed very low values for
phthalates and naphthalene, less than 100 ug/1, but
10
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high values for phenols. At FSA, where the phenols
content was 405 mg/kg, the leachate concentration
ranged from 2.8 to 3.8 mg/1 for both treated and
untreated soils.
Posttreatment leaching results of a 7-day test
performed by Environment Canada [1] with a 4:1
weight ratio of leachate to crushed solid showed very
low leaching of benzene and trichloroethylene, and
very high leaching of phenol. Approximately 80% of
the phenol contaminant was extracted, with other
organic components between the two extremes.
Pretreatment values were not performed for a
comparison.
The results for Basin F liquid at Rocky Mountain
Arsenal, as reported by WES [2], indicated that a
high percentage of the total organics, 86.7%, was
extracted after 5 cycles of a sequential leaching test,
with 67% extracted after the first cycle. Caution is
advised by the authors regarding extrapolating this
data to the field, because the test sample leached is
crushed and so its surface-to-mass ratio may be
different.
Leach tests using EP Tox were also performed, with
the results equivalent to other technologies
investigated by WES on Basin F liquid. The
conclusion of the WES report was that the HAZCON
process did not effectively stabilize the total organic
carbon in Basin F liquid.
A brief excerpt of confidential HAZCON report "B"
[6] on TCLP leach tests for pentachlorophenol (PCP)
showed nine points of data: HAZCON in a
subsequent letter indicates this was part of an
optimization study. The raw sample TCLP extract
concentration was 2.1 mg/1 PCP, while the nine
treated samples ranged from 1.1 to 27 mg/1.
Information on quantities of cement and Chloranan
were not provided. For eight of the analyses,
immobilization did not occur, but for the ninth,
where the leachate concentration was 1.1 mg/1, some
immobilization may have occurred, but it cannot be
confirmed because pretreatment and posttreatment
waste compositions are not available and the amount
of additives used is undefined.
In a report by Risk Science International for the
American Petroleum Institute [12], the HAZCON
process was one of many remediation technologies
evaluated on petroleum refinery wastes, including
API separator sludge, slop oil emulsion solids, and
two different filter cakes. The emphasis of the report
was to compare different types of processes,
mechanical, solvent extraction, thermal, and
stabilization/ solidification. However, for each type, a
number of technologies were treated. For
stabilization/solidification, Process #1 is the
HAZCON solidification technology. TCLP leachate
results for HAZCON-treated and untreated wastes
were presented; the API separator sludge showed a
reduction of approximately 99% for VOCs, BNAs,
organic acids, and metals. For the slop oil and the
filter cakes, the primary contaminants were VOCs,
and equivalent reductions were observed. However,
for these three wastes the leachate quantities of total
BNAs, organic acids, and metals are low and
scattered, so the technology's ability to immobilize
them cannot be confirmed. The ratio of waste to
cement to Chloranan was 2:1:0.05. These results are
good, particularly for the VOCs, but are not
consistent with the other results noted above.
Although not described in any detail, a proper
quality assurance program appears to have existed
for the analyses.
In an IWC study [10], the HAZCON process was one
of three solidification technologies evaluated on
organic sludges high in moisture. The HAZCON
process proved to be the best and was judged
satisfactory by the authors to meet regulatory
requirements. One apparently positive set of results
on the most difficult waste, which contained a total of
9% to 10% toluene, triehloroethylene, and benzene,
showed that the TCLP leachate for treated material
contained 23.4 mg/1 of these components. Leach tests
on untreated waste were not performed , so proof of
the technology's effectiveness cannot be confirmed
from these results.
TCLP leachate results were obtained on raw sludge
from the Sand Springs, OK Superfund site,
containing about 10% by wt oil and grease; the
HAZCON-treated material contained some VOC and
BNA. The treated waste leachates showed no
detectable levels of these organics. The untreated
waste extract values for the individual VOC
components ranged from nondetected to 50 ug/1.
Thus, some immobilization of organics may have
occurred. All the values reported are very low, and
analyses of the corresponding site waste were not
reported, although various Sand Springs site wastes
contained 10 to 100 mg/kg of these organic
contaminants.
Thus, it can be concluded that immobilization of
volatile and semivolatile organics does not usually
occur. This was observed in most of the tests
reported, with the Demonstration Test providing the
most complete data set available. Demonstration
Test results of the special leach tests, which attempt
to simulate the leaching of a solidified mass, were
the same order of magnitude as the TCLP leachate
concentrations. This would appear to show that the
TCLP results are indicative for this technology of
leaching from a solidified mass. However, as some
positive results on organic contaminant
11
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immobilization have been reported, some site-
specific tests may need to be performed.
Operations
Since most of the data on the HAZCON process is
based upon laboratory tests, operational data is only
available from the Demonstration. These results are
described in Appendix C. It was noted that although
HAZCON encountered many difficulties at
Douglassville, particularly for the 5-cu-yd runs,
design changes in the feed and mixing systems will
produce a reliable operating system.
Summary
Solidification/stabilization technologies generally
reduce contaminant mobility, particularly for toxic
metals, and increase volume. These techniques
nearly always leave some uncertainty about long-
term effectiveness, because laboratory tests can
neither fully duplicate field conditions over long
periods of time nor establish what actually happens
to the contaminants during treatment [14,15]. This
is true for the HAZCON technology also.
In conclusion the overall physical properties of
wastes treated by the HAZCON process are good,
although the potential for some remediation design
engineering and durability difficulties exists. The
innovative aspect of the HAZCON technology is the
use of Chloranan in conjunction with solidification
by Portland cement or other pozzolans. Chloranan
appears to 1) mitigate some of the detrimental effects
of organics on the rate of cement hydration reactions,
2) allow solidification of waste high in organics, and
3) improve some physical properties of the treated
material. Chloranan may also alter and improve the
ability of Portland cement to immobilize heavy
metals. However, it does not appear to enhance the
immobilization of organics, except possibly in select
applications. Thus, the technology appears to have
applications for the immobilization of heavy metals
in soils and sludges, where oil and grease levels are
high; and at sites where specific organic toxins are
sufficiently immobile and where physical soil
stabilization is deemed necessary. For other
applications, at sites containing organic
contaminants, treatability studies should be
performed.
Environmental Regulations and the
HAZCON Results
This section briefly discusses regulations pertaining
to hazardous waste cleanups. The discussion
particularly focuses on the Land Disposal Restriction
(LDR) standards and the use of stabili-
zation/solidification for Superfund actions.
The Resource Conservation and Recovery Act
(RCRA)
The Resource Conservation and Recovery Act
(RCRA) was passed in 1976 and expanded under the
Hazardous and Solid Waste Amendments (HSWA) of
1984. Section 3004 of HSWA prohibits land disposal
of untreated hazardous wastes after specified dates
and requires EPA to develop treatment standards,
which must be met before disposal is allowed.
After these standards, or Land Disposal Restrictions
(LDRs), become effective, wastes that are not treated
to meet those standards will be banned from land
disposal.
The key portion of this section of the 1984 HSWA is
the mandate for treatment standards for every waste
or group of similar wastes. All industrial hazardous
wastes were ranked according to their intrinsic
hazard and their volume. Based upon that ranking,
the list was divided into thirds, and a schedule was
prepared for establishing treatment standards.
Wastes that are considered hazardous based upon
their characteristics were scheduled for the final
third. The hazardous characteristics defining wastes
include ignitability , corrosivity, and reactivity, and
wastes that are hazardous based on extraction
procedure toxicity (EP Tox-leach test). Land disposal
of untreated wastes was prohibited on August 8,
1988 for the "First Third"; planned for June 8, 1989
for the " Second Third"; and May 8, 1990 for the
"Third Third" of the scheduled wastes.
Treatment standards are based on the performance
of the Best Demonstrated Available Technology
(BOAT) to treat the waste. A technology is
considered to be demonstrated for a particular waste
if the technology is in full-scale commercial
operation for treatment of that waste. Treatment
standards can be established either as a specific
technology or as a performance standard based on a
BDAT technology. When treatment standards are
fixed at a performance level, the regulated
community may use any technology not otherwise
prohibited to treat the waste so that it meets the
treatment standard.
On August 17, 1988, EPA promulgated treatment
standards for the First Third of the restricted
hazardous wastes. For three of these nonwastewater
inorganic wastes, F006, K046, and K022, the BOAT
performance standard is based on stabilization/
solidification technology; the standard for four other
wastes is also based on stabilization/solidification as
the BDAT for nonwastewater residuals (K001 and
K086) or ash residue (K101 and K102) following the
initial treatment.
On January 11, 1989, EPA proposed additional
treatment standards for the "Second Third" of the
12
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restricted hazardous wastes. EPA also proposed
additional treatment standards for some "First
Third" wastes and for "Third Third" wastes. Of these,
BDAT performance standards for F012, F006, and
F019 were based on stabilization/solidification.
In each case research to develop the performance
standard indicated that full-scale stabili-
zation/solidification is widely used throughout the
country to bind these metal waste constituents into a
cementitious matrix that immobilizes them, thereby
reducing their leaching potential.
The Comprehensive Environmental Response,
Compensation, and Liability Act (CERCLA)
The Comprehensive Environmental Response,
Compensation, and Liability Act (CERCLA) of 1980
as amended by the Superfund Amendments and
Reauthorization Act (SARA) of 1986 provides for
federal funding to respond to releases of hazardous
substances to air, water, and land. CERCLA
authorized EPA to prepare the National
Contingency Plan (NCP) for hazardous substance
response. The NCP defines methods and criteria for
determining the appropriate extent of removal,
remedy, and other measures. Specific techniques
mentioned in the NCP for remedial action at
hazardous waste sites include stabilization /solidi-
fication as a cost-effective technology for handling
contaminated soil and sediment.
Section 121 of SARA, entitled Cleanup
Standards,strongly recommends remedial actions
using on-site treatment that"...permanently and
significantly reduces the volume, toxicity,or mobility
of hazardous substances." The actions must assure
protection of human health and the environment,
must be in accordance with the NCP, and must be
cost-effective. This means that when selecting an
appropriate remedial action, the first step is to
determine the level of cleanup that is necessary to
protect the environment, and the second step is to
choose the most cost-efficient means of achieving
that goal. SARA further states that "off-site
transport and disposal... without such treatment
should be the least favored alternative remedial
action where practical treatment technologies are
available."
SARA also added a new criterion to CERCLA to be
used in determining cleanup priority: the
contamination or potential contamination of the
ambient air that is associated with a release. Since
stabilization/solidification often involves the
treatment of organic constituents, this criterion is of
primary concern in that the method of
stabilization/solidification selected must not release
VOCs into the ambient air.
Superfund Response Actions
Superfund response actions must meet "applicable or
relevant and appropriate requirements" (ARARs) for
cleanup. If land disposal restrictions are applied to
Superfund actions, they may be "applicable or
relevant and appropriate." LDRs are applicable
when existing federal or state laws can be utilized to
have direct authority over placement of restricted
hazardous wastes in or on the land. LDRs may be
relevant and appropriate when Superfund hazardous
substances are sufficiently similar to restricted
industrial hazardous wastes such that use of LDRs is
suited to the circumstances of the releases.
In addition to industrial process waste, the HSWA
also addresses soil and debris that result from
CERCLA response actions and RCRA corrective
actions. Effective August 8, 1988, EPA issued a
national capacity variance through November 8,
1990 for all CERCLA/RCRA soil and debris, which
are contaminated with hazardous wastes whose
BDAT standards are based upon incineration.
In the meantime, the EPA intends to develop
separate BDAT treatment standards for soil and
debris, because the BDAT standards were developed
for industrial waste processes, which are often
different from the soil or debris waste matrices in
terms of chemical/physical composition,
concentrations, and media within and among sites.
Until standards are developed for soil and debris,
remedies will continue to be selected on a site-
specific basis. Since these remedies are not likely to
conform to the BDAT standards for industrial
process waste, a variance is required.
Under a treatability variance, treatment will be
applied with the goal of achieving substantial
reduction in toxicity and mobility through treatment
to a range of treatment levels. These treatment
levels were developed from a data base that EPA has
compiled of treatability data for contaminated soil.
The data were divided into treatment for organic and
inorganic constituents, and further divided into
structural-functional groups based upon treatability
for the organics, and for individual metals for the
inorganics.
The treatment ranges for soil and debris have been
developed as interim guidance until final treatment
standards for soil and debris are promulgated.
Modifications to the treatment ranges may occur and
will be issued as revised guidance as additional
treatment information becomes available.
In developing the interim guidance, solidification
and stabilization technologies have not been
demonstrated to be effective technologies for the
13
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treatment of organic wastes. Solidification and
stabilization data resulting from the treatment of
organic wastes were, therefore, not considered.
Consequently, the treatment levels are expressed as
total composition values for organics and as leachate
values for inorganics.
Toxic Substances Control Act (TSCA)
The disposal of PCBs and PCB-contaminated
materials, 50 ppm by wt and greater, are regulated
under the provisions of the Toxic Substances Control
Act of 1976. The regulations, which are found in 40
CFR 761.60, address disposal requirements in
relation to the concentration of the PCBs in the
waste. PCBs in concentrations of 50 to 500 ppm may
be disposed of either by landfilling or incineration.
PCBs in concentrations greater than 500 ppm must
be disposed of by incineration. A contaminated waste
under 500 ppm by wt is a candidate for
stabilization/solidification. Unless regulations
change, PCBs in concentrations greater than 500
ppm may not be disposed of by stabili-
zation/solidification technology. Also, several states
have their own PCB regulations that may impact on
the use of stabilization/solidification technology.
Comparison of Regulations to HAZCON Results
Stabilization/solidification has been shown to be an
effective technology for treating metals. In addition,
the HAZCON process appears to overcome the
inhibiting effect from the presence of organics on the
solidification process. However, there is uncertainty
concerning the potential use of stabili-
zation/solidification for Superfund soils
contaminated with organics. The Land Disposal
Restriction standards have been developed with the
assumption that stabilization/solidification is not a
BDAT for organics. Test results from the
Douglassville demonstration for the HAZCON
technology tend to substantiate this assumption, as
long as the TCLP leach test is assumed as the sole
criterion for effectiveness.
Superfund legislation requires consideration of
alternatives that permanently and significantly
reduce the volume, toxicity, or mobility of hazardous
substances. Since remedies are chosen site-
specifically based on cost-effectiveness, there may be
applications where stabilization/solidification is an
acceptable remedy for wastes with some organics.
This will be especially true if a measure of
performance other than TCLP is chosen.
It is more feasible to evaluate the HAZCON process
with respect to regulations and treatment levels for
metals-bearing wastes. There are regulations and
approved delisting petitions for several waste-coded
materials, primarily F006, which is electroplating
wastes. For these metals, barium, cadmium, lead,
chromium, nickel, and mercury, some treated waste
leachate values exist that provide a guideline for
leaching results. In addition, the national capacity
variance for RCRA and CERCLA soil and debris
provides proposed treatment levels for contaminated
soils. These treatment concentrations for leachates
are in the range of 0.1 to 3.0 ppm when the metals in
the waste are below the threshold range, which is
essentially the same order of magnitude as the
values in the Demonstration for all metals except
lead; lead soil concentrations were higher than the
threshold value by a factor of 10-70. Thus, only a 95%
reduction factor is required.
A comparison of the HAZCON results and the
regulatory values are shown in Table 1. Based upon
the available data, primarily from the
Demonstration, the HAZCON process would readily
meet the range of regulatory concentration values
that are currently accepted. Even for the high lead
values in the Demonstration waste, the treatment
range and reduction factors were readily met.
Waste Characteristics and Performance
of the Technology
Solidification/stabilization processes involve the
addition of agents that are intended to mechanically
or chemically bind or encapsulate hazardous
constituents to prevent their release into the
environment. These processes generally increase the
strength and decrease the permeability of the
solidified mass. In general, the stronger, more
impermeable, and more durable a treated waste, the
more effectively it will contain hazardous
constituents. If the material does not fragment,
create dust, or increase the surface area available for
leaching, losses will be minimized. Some processes
produce solid pellets, where compressive strength is
not a criterion.
The HAZCON process is a cement-based process
whose design concept is to solidify and immobilize
waste contaminants. The principal difference
between this process and other cement-based
processes is the use of a proprietary component-
Chloranan-which is claimed to permit solidification
of waste materials with high organic concentrations.
It has long been known that organics may inhibit the
cementation process, which may result in less
favorable physical characteristics of the solidified
product, such as UCS, permeability, and bulk
density.
Batch system feeds are preferred by HAZCON, Inc.
to continuous feeds, since the developer believes feed
variations can be more easily identified with a batch
system and steps can be taken to adjust admix ratios
to compensate for feed variations. The HAZCON
process claims to be able to handle any type of feed.
Matrices preferred by HAZCON in order of
14
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Table 1. Comparison of HAZCON Results to Some Regulatory Values for Metals
Regulatory range, mg/IW>
Metal
Pb
Cr
Ni
Cd
Cu
LDRs
0.25-0.5
0.32
2.2
0.066-0.14
-
Delisting
0.31-0.5
1.7
0.048-0.32
0.063
-
Interim
Guidelines
0.1-3.0
0.5-6.0
0.5-1.0
0.2-2.0
0.1-3.0
HAZCON
untreated waste,
mg/l
17.9
< 0.008
0.07
0.13
-
HAZCON
treated waste, mg/l(a>
(waste concentration, mg/kg)
0.40
< 0.007
0.025
< 0.004
0.41
(22,400)
(95)
(17)
(6)
( 5,680)(0
(a)Leaching results after 28 + days of curing.
The 7-day core leachate from the Demonstration Test was 0.070 mg/l.
<°)Rocky Mountain Arsenal - Basin F pond water. There are not any regulatory values for copper.
W>AII values based upon using EP Toxicity leaching test.
Results from the Demonstration Test using TCLP.
preference are soils, sludges, emulsions, and lastly
liquids, with the preferred contaminants being
metals, organics, and lastly volatile organics.
Although the Chloranan admix was selected for use
at the Douglassville site and usually not defined in
the other tests of the HAZCON technology, other
formulations or admixes can be chosen dependent
upon the waste contaminants. HAZCON is
continuing to develop admixes that are contaminant-
specific, but has not provided any information on
what these changes are or the factors that influence
their selection.
HAZCON usually tests all site materials before
operation to determine the proper formulations,
admixes, and ratios for optimum results. However,
this was not done for the Demonstration, and
conservatively high levels of Chloranan and cement
were utilized. Cement-based mixtures generally are
used, as they have proven to be effective, but the
equipment can process other pozzolanic (fly ash, kiln
dust, etc.) mixtures as well.
The HAZCON system is claimed to work best with
soil feeds; sticky materials are more difficult to treat
because of materials handling problems. However,
during the Demonstration, the sticky filter cake was
processed more easily by the MFU than the other soil
feeds. Information from other tests on ease of
processing various feedstocks was not reported. The
10 cu yd/hr continuous system used in the SITE
Project works best with materials of a consistency
ranging from soil-like to light sludges. Liquids
cannot be handled because of insufficient equipment
component sealing.
Variability of feedstock components can result in
product problems. This can be overcome by using
larger than optimum ratios of admixes, but at the
cost of volume increase or the necessity to frequently
sample the feedstock to ensure constancy. Out-of-
specification product material may be recycled while
still in a slurry state, but after solidification the
problems with recycle become much more serious.
For further treatment, special equipment such as
crushers, screens, etc., are required. In addition,
laboratory analyses may have to be obtained
promptly to minimize the quantity of recycle.
Cold weather (below 40°F) can affect the hydration
reactions and thus the product quality. However,
this effect may be overcome by the use of special
cements or by preheating the process streams and
feedstock to a maximum of 40°F to 50°F, which would
avoid volatilization of the light organics. Preheating
of any feed materials would increase equipment and
operating costs. Since the hydration of cement is
exothermic, additional heat is not required once the
reactions commence.
Ranges of SITE Characteristics Suitable
for the Technology
Currently HAZCON has available two continuous
Mobile Field Blending Units (MFU) that can process
up to about 10 cu yd/hr of untreated soil. HAZCON
indicates that five 100 cu yd /hr batch systems are in
the planning stages and are expected to be available
in the fall of 1988; they will be managed through five
planned regional offices tentatively selected to be
opened in Atlanta, Chicago, Houston, Los Angeles,
and New Jersey. Prior to the start of operations of
the 100 cu yd/hr systems, HA2ICON intends to serve
as the prime contractor to design site-specific batch
remediation system components and to subcontract
the use and operation of the equipment. Remediation
time constraints, areas of remediation, and costs will
determine which system will be selected for
remediation of a specific site. Multiple systems
operating in parallel will allow handling of large
sites. HAZCON has indicated that sites greater than
15
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those capable of being handled by the multiple 100-
cu-yd arrangement may be handled by subcontracted
process equipment. All equipment is selected based
on contaminants and costs. HAZCON places no
limits on the size of the site that can be remediated.
For a site the size of Douglassville-250,000 cu yd to
be remediated-assuming a 90% on-stream factor and
24 hours processing per day, one 100 cu yd/hr system
could remediate the entire site in approximately 4
months. The 10 cu yd continuous system would take
more than 3 years to complete the remediation.
The 10 cu yd/hr system is compact, weighs
approximately 17,000 pounds (empty) is mobile, and
requires no special over-the-road or operating
permits. Thus, it would be accessible to nearly all
hazardous waste sites. The system must be nearly
level to operate, and the site soil must be able to
support the system's weight fully loaded with
cement, water, feedstock, and admixes, as well as
support auxiliary equipment and storage tanks.
Therefore, some site preparation work may be
required to level the terrain, pour slabs, and build
access roads. The trailer and support equipment
require a setup area of about 500 sq ft. Additional
area is needed for storage of cement, Chloranan, and
fuel, as well as personnel facilities for any long-term
project. The moving components-pumps, feeders,
etc.-are driven by a hydraulic power pack deriving
its power off the diesel engine of the transporting
vehicle. The cement is air conveyed from a separate
cement truck to the cement hopper on theMFU.
The 100-cu-yd/hr proposed system consists of a feed
aggregate bin where the waste feed is weighed, a
cement feed bin, and a rotary drum mix tank. The
feed and cement are combined and conveyed to the
mix tank, where water and admixes are added.
Pumpable materials can be metered directly into the
mix tank. The system will be mounted on an over-
the-road trailer and will weigh approximately 40,000
pounds (empty). Some site work may be required to
level an area for the trailer or to pour support slabs.
Good traction for the earth-moving equipment is
required. The trailer and support equipment
provided by HAZCON will occupy approximately a
1,000 sq ft area. Additional area is needed for
cement, fuel, and Chloranan storage bins, as well as
personnel facilities. The system power source for the
HAZCON unit is a 60 KW diesel generator, plus
additional power for support systems.
Although the MFU used at Douglassville is not
corrosion-resistant, the proposed 100-cu-yd/hr batch
system's major components, such as the feed and
aggregate bins, belts, and rollers, will be corrosion-
resistant stainless steel. The new systems are
designed to be operated under negative pressure to
reduce emissions. The small MFU is not leak-tight
and would experience difficulty in maintaining
negative pressure. The MFU is claimed by HAZCON
to be explosion-proof, and at least one of the five 100-
cu-yd/hr systems will be designed to be explosion-
proof.
Auxiliary equipment consists of storage tanks and
feed equipment for the fuel, Chloranan, and cement;
a personnel trailer for administrative functions; on-
site sampling facilities for any laboratory work;
parts supplies; health and safety supplies; and an
area with equipment for personnel and equipment
decontamination.
Typically, the process consists of excavating the
waste; transporting it to the solidification unit; and
sizing, processing, and removal of the solidified
product to a permitted landfill. It may be left on a
site if it meets the established site regulations or, for
a coded waste, the land ban (RCRA) requirements.
The placement of the treated waste back into the
original excavations is possible, although this has
not yet been satisfactorily demonstrated for most
system applications. Disposal on or off site for
rejected screened materials must be anticipated.
Local bridges and roads must be able to support
standard excavating equipment.
Off-site migration of airborne contaminants or
vapors can be a problem during excavation, mixing,
and transport of the waste to remediation. High
water tables can result in groundwater
contamination during excavation; high groundwater
that results in bearing losses at the site could
preclude use of the technology without appropriate
support slabs for equipment and roads for transport.
The HAZCON technology can process a wide range of
feedstocks, from dry soils to liquid wastes. However,
monitoring of the feedstock is required, so that
adjustments in the quantity of cement, Chloranan,
and water can be made. All feedstocks should not be
processed with the same quantities of additives, or
the economics of the process will suffer.
Material Handling Required by the
Demonstrated Technology
A successfully solidified product from HAZCON's
continuous system is dependent on proper time,
weight, flow calibrations, and ratios of the admixes.
Component feed variations, such as "slugs" of oil and
grease in an otherwise uniform soils feed, cannot be
easily handled by this system, as would be the case
for many systems, and could result in improper
mixture ratios. Continuous measurements of oil and
grease or of individual contaminant levels is not
possible. In order to overcome this disadvantage the
process is capable of using higher-than-required
admix ratios, but this procedure is less cost-effective.
HAZCON, therefore, prefers to use batch systems
16
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where they claim the mix ratios can be carefully
monitored, variations in the feed components can be
easily adjusted, and improved mixing can be applied.
HAZCON does not define how feed variations will be
identified or defined.
Heavy earth-moving equipment is required to
properly excavate the feed stock material and
transport it to the system free inlet. Both the
continuous and batch systems require air monitoring
equipment to track organic and dust exposures
during excavation, transport, and feed to the system.
Feed materials must be screened and/or crushed to 3-
inch diameter for the continuous system, and to 6-
inch diameter for the 100 cu yd/hr batch system.
Grinding, crushing, or other appropriate size
reduction equipment may be used to pretreat the
feedstock. HAZCON claims that contaminated
water, whether surface or ground water, can be used
in the process as the water additive.
Any site conditions that could interfere with
excavation would present a problem for the
technology, as they probably would for most other
similar technologies. For example, a high water
table might require process adjustments, present
excavation problems, and might indicate insufficient
support for access by heavy equipment. Frozen
ground could present an excavation, screening, and
processing problem.
At the Douglassville site, the feed material had a
tendency to pack when compressed, causing
HAZCON to reduce the feedrate to slower than
originally intended because the feed screw had a
tendency to ride up on the material and jam. The soil
also was fed to the 7 1/2 cu yd feed hopper only as
rapidly as the process screw could process it, which
added significant time and expense to the site
support operations. In addition, an uncontrolled and
crudely measured water feed stream was fed directly
to the storage bin to facilitate soil movement.
HAZCON suggests, without providing any details,
that in such circumstances, pretreating the feed
material to obtain a nonpackable slurry would
resolve such difficulties. HAZCON indicates that the
100-cu-yd batch system is not expected to experience
the same problems.
Personnel issues
Personnel required for the 10 cu yd/hr system at
Douglassville were four operators as a minimum, not
including operators of other earth-moving
equipment, office and laboratory workers, etc.
HAZCON claims that the 100 cu yd/hr batch plant
will require two peoplea control room operator and
an outside personplus earth-moving, office, lab, and
maintenance personnel.
HAZCON claims that personnel are usually widely
available, and if not trained can be trained on site by
HAZCON. However, these people must pass
appropriate physical exams and have completed an
EPA-approved 40-hour hazardous material training
course, which reduces local manpower availability.
Personnel are subjected to the standard OSHA
requirements for operating moving equipment and
would be required to wear the proper personal
protective equipment dictated! by the specific site
conditions and contaminants.
Testing Procedures
The samples taken and analytical procedures used
for the Demonstration Test were selected based upon
the information required to provide answers to the
technology evaluation criteria. The two important
technical criteria to evaluate any stabili-
zation/solidification technology are:
Mobility of the contaminants
Durability of the solidified mass
Tests were drawn from various related fields and
applied to hazardous waste to obtain the answers.
The most important factors in evaluating
contaminant mobility are:
To relate pretreatment to posttreatment results
To measure contaminant concentration in the
waste for the samples being used in leaching
tests
Therefore, for all pretreatment and posttreatment
samples for the Demonstration Test, soil analyses for
VOC, BNA, PCB, and heavy metals were performed
before samples of the same material were leached.
The TCLP test is the most widely accepted leaching
procedure and is capable of measuring both organics
and heavy metals. It is the most important test in the
program for evaluating contaminant mobility. Two
additional leach tests, MCC-1P and ANS 16.1, were
also used on selected posttreatment samples; they
attempt to simulate leaching from a solidified mass.
MCC-1P simulates a stagnant groundwater regime
and ANS 16.1 a more rapidly moving groundwater
where the boundary (surface) concentrations are
below saturation levels. These tests were drawn from
the nuclear industry and are relatively expensive to
perform. The three tests use different leachate-to-
solid ratios, so only a qualitative relationship
between test results is valid.
Following the TCLP test, the next most important
test is permeability, which is a measure of flow of
water through the solid. Since water is the leaching
17
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agent, only water coming in contact with the
contaminant can leach the toxins out. A constant
head permeability test, such as ASTM D-2434-68,
can be used for untreated soils where permeabilities
are relatively high, more than IxlO-4 cm/sec. For the
treated soils, where permeabilities may range from
1x10-6 cm/sec to IxlO-10 cm/sec, the falling head
permeability test is used. This is described in Test
Methods for Solidified Waste Characterization
(TMSWC) (a draft document prepared by the
Materials Characterization Center of EPA).
Once the contaminant is immobilized, the concern is
how long it will remain that way. Therefore, tests
were performed to provide information on potential
durability of the treated soil. In addition, a long-term
monitoring program, for this SITE project over a
five-year period, is included; samples will be
collected from treated soil that is buried at the
Douglassville site. The most prominent test is UCS,
which provides a measure of the quality of the
solidified mass. It is a test commonly used by the
cement industry to evaluate cement quality and is
relatively inexpensive.
Wet/dry and freeze/thaw 12-cycle tests provide
additional information on degradation of the
solidified material. The tests used are described in
TMSWC and are very similar to the ones used by
ASTM. These tests, although more severe than field
weathering, provide an indication as to whether the
solidified material when saturated or near
saturation, as when buried, will disintegrate over
the first few weathering cycles, which may take
place within the first few years. The tests cannot be
used to quantitatively predict the life of the solidified
mass in terms of years, decades, or centuries.
The final group of tests, which can be performed and
interpreted at only a few laboratories, go under the
general heading of microstructural analyses. Both
treated and a few untreated soil samples are
analyzed by the following methods:
X-ray diffraction (XRD) - defines crystalline
structure, which can indicate changes from the
normally expected structure.
Microscopy both optical and scanning electron
(SEM).- These techniques characterize crystal
appearance, porosity, fractures, and presence of
unaltered waste forms. From these observa-
tions, mixing efficiency can also be obtained.
Energy dispersive x-ray spectrometry -
elemental analysis of crystal structures can be
determined.
These tests are proven methods of analysis for
understanding the mechanism of structural
degradation in materials similar to those of the SITE
Demonstration. The literature is replete with
examples of SEM and XRD analyses of soil, cement,
soil-cement mixtures, and each of these mixed with
various inorganics and organic compounds.
However, there have been relatively few studies of
the microstructure of complex waste/soil mixtures,
such as those resulting from a stabiliza-
tion/solidification procedure. Consequently, in some
cases, interpretation of the microstructural
observations may be difficult.
These observations provide information on the
potential for long-term durability of the solid. They
cannot quantitatively predict the life of the solid
mass or provide a direct relationship to the other
tests described above. In the future, if a body of data
is developed from long-term monitoring programs,
the predictability of these procedures will improve.
Another test of importance, but not directly related
to the two technology evaluation criteria, is the
inexpensive test of measuring bulk density. In all
solidification processes, pozzolans and special
additives, along with water in many cases, are added
to the waste. This could lead to major waste or soil
volume changes, which may affect the remediation
procedures. Bulk density measurements of the soil
before and after soil treatment, along with a
material balance, will provide a method of
calculating volume change during the remediation
process.
The other physical testsmoisture, pH, and particle
size distribution (PSD)are typical soils tests and
provide background information that could become
important if problems occur. Moisture and pH
analyses are very inexpensive, and a PSD is
moderately priced.
18
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Section 4
Economic Analysis
Introduction
A primary purpose of the economic analysis is to
attempt to estimate costs (not including profits) for a
commercial-size remediation. It was expected that
stabilization/solidification technologies would be less
expensive than most other technologies, such as
incineration. The basis for this analysis was
remediation of part of the Douglassville site. Because
the Douglassville Superfund site is a spacious area in
a rural setting, it allows a simplification and
elimination of some potentially expensive site-
specific costs. Many costs are site specific, being
affected by such factors as site geology; being in a
floodplain (as at the Douglassville site); type and
quantity of contaminants; proximity to the
community or to other industrial sites; regulatory
requirements, and local costs of labor, utilities, and
raw materials.
Due to the short-term nature of the Demonstration
and the fact that labor and chemical expenses
dominate the remediation costs, the actual test costs
for HAZCON and EPA were not used. However, since
HAZCON used a small-scale (300 Ib/min),
continuous, commercial unit, the capacity, on-stream
factor, and chemical usage during the Demonstration
Test comprise the starting basis for a commercial
cleanup estimate. One change was made for the
analysis in each of these variables, which would
progressively improve the commercial potential.
First, the existing small-scale unit was assumed to
operate at on-stream factors of 70% and 90%. Then,
based upon HAZCON's recommendations for the size
of the unit that will be available in the foreseeable
future, a 2,300 Ib/min batch unit is assumed at both
70% and 90% on-stream factors. If a treatability
study had been performed by HAZCON on
Douglassville wastes, reduced quantities of cement
and Chloranan might have been used. However,
since this did not occur, HAZCON utilized a
conservative approach and probably used more
cement and Chloranan than required for all or most
of the plant areas. HAZCON has indicated that lower
cement and Chloranan rates are likely to be used,
possibly 25% to 50% by wt lower. Therefore, a 33%
reduction in usage for each of the above conditions
was investigated. Thus, eight cost scenarios were
developed ranging from using the existing unit at
Demonstration conditions to using future commercial
equipment at optimized chemical consumptions.
These costs are presented in Table 2.
Important assumptions were made in preparing the
eight cases that could significantly impact the
remediation costs. Many actual or potential costs that
exist were not included as part of this estimate. They
were omitted because site-specific engineering
designs would be required, which were beyond the
scope of this SITE project. Therefore, certain
functions were assumed to be performed by others
and were not included in the estimates. The major
assumptions that reduced the cost estimates were:
A prime contractor is at the site who will perform
many site functions including many services not
charged to the HAZCON remediation and so only
partially included in this cost estimate. These
are:
Site preparationroads, access to feedstock,
and providing utilities to plant battery limits.
Battery limits can be defined as a space
envelope that includes all of the HAZCON
equipment plus support equipment to which
utilities and access must be provided.
Installation of support tankage, pumps,
piping, etc., for feeding the cement,
Chloranan, and fuel to the operating unit.
Removal of support equipment at the
completion of the cleanup.
A large volume increase between untreated and
treated wastes exists. Thus, the total treated
waste may not be able to be placed back into the
original excavation. A cost for removal to a
landfill is not included and could be quite
substantial. Even moving the excess material to
treated waste may not be able to be placed back
into the original excavation. A cost for removal to
a landfill is not included and could be quite
substantial. Even moving the excess material to
19
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Tablo2. Estimated Costa.c
Demonstration
Test Chemical Consumption
Reduced Chemical Consumption
300 Ib/min
On-Stream Factor
90% 70%
2300 Ib/min
On-Stream Factor
90% 70%
300 Ib/min
On-Stream Factor
90% 70%
2300 Ib/min
On-Stream Factor
90% 70%
Site Preparation
Permitting and Regulatory
Equipment
HAZCON, $>»
Support, S/ton
Equipment Rentals, $/ton
Contingency, $/ton (10% of Direct
Costs)
Startup and Fixed Cost, $lton
Operator Training
Site Mobilization
Depreciation (10% of Direct Costs)
Insurance and Taxes
(10% of Direct Costs)
tabor Coste, $lton
Salaries and Living Expenses
Administration (10% of Direct Costs)
Supplies - Raw Materials, $/ton
Cement
Chtoranan
Supplies - Utilities, $lton
Fuel
Electricity
Water
Effluent Treatment
Residual Transport
Analytical, S/ton
Facility Modifications, $lton
(10% of Direct Costs)
Site Demobilization, $lton
TOTALS, $/ton
100,000 100,000 300,000 300,000 100,000 100,000 300,000 300,000
2.25 2.25 6.75 6.75 2.25 2.25 6.75 6.75
8.05 10.36 1.05 1.35 8.05 10.36 1.05 1.35
0.25 0.32 0.11 0.13 0.25 0.32 0.11 0.13
0.84
0.83
0.25
0.25
0.84
0.83
0.32
0.32
0.84
0.83
0.11
0.11
0.84
0.83
0.13
0.13
0.84
0.83
0.25
0.25
0.84
0.83
0.32
0.32
0.84
0.83
0.11
0.11
0.84
0.83
0.13
0.13
50.32
0.25
50.00
66.67
1.00
0.03
0.08
5.65
0.25
0.83
187.80
64.70
0.32
50.00
66.67
1.29
0.03
0.08
6.50
0.32
6.56
0.11
50.00
66.67
0.23
0.07
2.26
0.12
8.44
0.13
50.00
66.67
0.29
0.07
2.40
0.14
50.32
0.25
33.33
44.44
1.00
0.03
0.08
5.65
0.25
64.70
0.32
33.33
44.44
1.29
0.03
0.08
6.50
0.32
0.83 0.83 0.83
205.98 136.65 139.13
0.83 0.83
148.90 167.08
6.56
0.11
33.33
44.44
0.23
0.07
2.26
0.12
0.83
97.75
8.44
0.13
33.33
44.44
0.29
0.07
2.40
0.14
0.83
100.23
a This cost analysis does not include profits of the contractors involved.
b Not used directly but is used for the estimate of other costs.
o The American Association of Cost Engineers defines three types of estimates: order of magnitude, budgetary, and definitive. This estimate
would most closely fit an order of magnitude estimate with an accuracy of +50% to -30%. However, as HAZCON is a new technology,
the accuracy range is probably significantly wider.
20
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another area at the Douglassville site, along with
land contouring, would add appreciable expense.
Permitting and any environmental monitoring of
operations for any regulatory authority are not
included.
Operations are assumed to be 7 days per week
and 24 hours per day. Any reductions in this
schedule would add to the remediation cost by
increasing the labor costs.
Results of Economic Analysis
The results of the analysis show a cost per ton range
of $97 to $205. The lowest value is based upon
HAZCON's expectation of reducing chemical
consumptions by 33%, attaining an on-stream factor
of 90%, and using a new 2,300 Ib/min batch
processing unit . Since a 70% on-stream factor is
closer to that actually seen at Douglassville, PA, the
costs for this level of operating efficiency are also
calculated. These cost values are higher than those
normally claimed by HAZCON, see Appendix B. In
addition, many costs not charged to HAZCON as
mentioned in the previous subsection and discussed
in more detail under Basis of Economic Analyses,
would increase the actual cost to those responsible for
remediating the site. Extreme care in defining the
ground rules for the economic analysis is required.
The results show that 85% to 90% of the costs are for
raw materials (cement and Chloranan) and labor.
HAZCON provided the cost for cement at $50/ton
delivered, which may be a little low for the
Douglassville area, and for Chloranan at $3.00/gallon
($66.67/ton). The labor costs include 17 people to
operate the HAZCON equipment, 17 people to
provide support services such as feedstock
preparation, plus 5 management and office
personnel. The same size work force for both the large
and small processing unit is assumed.
The two largest potential savings in remediating the
site result from chemical use reductions and the
increased size of the processing unit, which would
reduce operating time to remediate the same
quantity of contaminated soil, compared to the 300
Ib/min system used at the Demonstration. The next
largest cost factors are on-stream time, analytical
costs, and equipment rentals and consummables.
This suggests that larger remediations would be
more cost-effective, and that equipment operation
must be closely monitored to ensure high on-stream
factors. Stable operations may also allow reduced
sampling frequency, but this potential variable was
not included in the economic analysis.
Basis of Economic Analysis
The cost analysis was prepared by breaking the costs
into twelve groupings. Theses will be described in
detail as they apply to the EIAZCON process. The
categories, some of which do not have costs associated
with them for this technology, are as follows:
Site preparation costs including site design and
layout, surveys and site investigations, legal
searches, access rights and roads, preparations
for support facilities, decontamination facilities,
utility connections, and auxiliary buildings.
Permitting and regulatory costs including
permit(s), system monitoring requirements, and
development of monitoring and analytical
protocols and procedures.
Equipment costs broken out by subsystems,
including all major equipment items: process
equipment, materials handling equipment, and
residual handling equip>ment. Also included
descriptions of the equipment specifications (i.e.,
throughput and utilization, rate).
Startup and fixed costs ~ broken out by
categories, including mobilization, shakedown,
testing, working capital, depreciation, taxes, and
initiation of environmental monitoring pro-
grams.
Labor costs including supervisory and
administrative staff, professional and technical
staff, maintenance personnel, and clerical
support.
Supply costs ~ includes the raw materials,
cement, and Chloranan. This is the largest of the
twelve cost categories for the HAZCON
technology, and any design optimizations based
on treatability studies or direct field experience
could have a large impact on the bottom line.
Supplies and consumables costs both the
utilities required, which include fuel, electricity,
and water, and any byproducts or posttreatment
of the treated soil.
Effluent treatment and disposal costs both on-
site and off-site facility costs including
wastewater disposal and monitoring activities.
Residuals and waste shipping, handling, and
transport costs including the preparation for
shipping and actual waste disposal charges.
Analytical costs including laboratory analyses
for operations and environmental monitoring.
21
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Facility modification, repair, and replacement
costs including design adjustments, facility
modifications, scheduled maintenance, and
equipment replacement.
Site demobilization costs including shutdown,
site cleanup and restoration, permanent storage
costs, and site security.
Some general ground rules defining the basis of the
estimates are as follows:
The remediation occurs at the Douglassville
Superfund site, No. 102 on the National Priority
List(NPL).
A total of 35,400 tons of soil are processed in each
of the eight cases estimated. (This figure is based
upon the HAZCON MFU used for the
Demonstration Test operating at 300 Ib/min,
continuously for six months at a 90% on-stream
factor.)
There is a prime contractor on site responsible for
the complete site cleanup, who will provide
certain functions for the HAZCON processing
unit, such as site preparation, whose costs are not
included.
The twelve cost factors, along with the assumptions
utilized, each are described below.
Site Preparation Costs
It is assumed that this work will be performed by the
site prime contractor and that there will be no
charges to the HAZCON cleanup. This assumes that
roads, site preparation for the HAZCON MFU and its
support equipment, and access to the feedstock are
provided by others, along with the supply of
electricity and water to battery limits and connecting
them to the system. It is also assumed that the design
of the facilities and any final contouring of the land
will take into consideration that the Douglassville
Superfund site is in a 100-year floodplain and that it
is covered by the Pennsylvania Scenic Rivers Act of
1972. These latter two factors may add considerable
cost to any remediation.
Equipment Costs
Based upon information provided by HAZCON, the
capital cost for the small continuous processing unit
used during the Demonstration Test is $100,000, and
the cost of their future large batch processing system
is $300,000. In addition to the HAZCON mobile unit,
there are stationary facilities required for the storage
of cement, Chloranan, and fuel oil. In addition, there
are pumps for the fuel and Chloranan and an air
conveying system for the cement. This involves added
expenses within battery limits: site preparation,
foundations, interconnecting piping, support steel,
instrumentation, and electrical supplies. For the
small HAZCON system, second-hand support
equipment may be utilized that might be discarded at
project completion.
Tanks and pumps might be available from used
equipment suppliers. Even with refurbishing and
checkout, major savings both in time and cost may be
realized. It is assumed that there is a project charge of
$80,000 or $2.25 per ton of soil processed. For the
large system, the charge is assumed to be triple this
amount, or $6.75 per ton of soil. A preliminary
design, along with ground rules for operation at the
site, would be required to provide a more accurate
estimate. Since there are so many variables involved
and this type of design is outside the scope of the
SITE Program, this preliminary design was not
performed.
A contingency cost, approximately 10% of the direct
costs on an annual basis, is allowed for unforeseen or
improperly defined cost definitions. This is separate
from the previously described design basis
uncertainties.
One of the largest costs after chemicals and labor is
the rental of equipment and consumables. Rental
equipment includes such items as: front-end loaders,
backhoes for soil excavation and transport, a steam
cleaner for decontamination, a pickup truck, a drill
rig, and personnel facilities. This latter item includes
expendable health and safety clothes, health and
safety instrumentation, trailers for office space,
sanitary facilities, lights, and sampling materials.
Based upon a six-month program, this is estimated to
add up to about $285,000. It is assumed that these
costs are directly proportional to the time at the site.
Permitting and Regulatory Costs
Since Douglassville is a Superfund site, it is assumed
that no permits will be required, neither federal nor
state. The need for developing analytical protocols or
monitoring records is assumed not to exist. On non-
Superfund sites, this activity could be expensive and
very time consuming.
Startup and Fixed Costs
The costs included in this group are operator
training, initial shakedown of the equipment,
equipment depreciation, and insurance and taxes.
It is assumed that three days of operator training are
required for the HAZCON MFU operators,
supplementary field personnel, the Site Health and
Safety Officer, and the sampling technician. The
22
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costs include salaries, overheads, and expenses at the
rates described under the grouping for labor.
Initial startup includes setup of the HAZCON
equipment and checkout of its operation. This is
equivalent to the HAZCON site mobilization, but
travel costs to the Douglassville site are not included.
Three days are allowed for this function. The
installation of the support tankage, pumps, etc., is
not assumed as a charge to the remediation. This is
probably a significant cost, equivalent to many
dollars per ton, but the design of a system and a
budgetary or detailed estimate of it is outside the
scope of this economic analysis. For purposes of this
estimate, this installation work is assumed to be by
the site prime contractor and not charged directly to
the HAZCON operation.
The depreciation costs are based upon a 10-year life
for all the equipment. Therefore, the costs are based
upon the write-off of $180,000 worth of equipment for
the small system and $540,000 for the large system.
Insurance and taxes are lumped together and are
assumed for the purposes of this estimate as 10% of
direct costs taken on an annual basis.
coordinator, health and safety officer, project
manager, and office managers are estimated at
$120/day. A contingency of about 10% to 15% for all
personnel is also allowed for overtime plus
unexpected expenses. This results in a total average
daily cost of approximately $9,800.
An additional labor-related expense item is
administrative costs, which include office expenses,
such as supplies, telephones, furniture, and
reproduction equipment, but not salaries. This cost is
assumed to be 10%, on an annual basis, of direct
costs.
Supply Costs
The cost of raw materials includes typical variable
costs and is the largest expense; the raw materials
are cement and Chloranan. The costs were provided
by HAZCON and were assumed to be on a delivered
basis. Cement was charged to the project at $50/ton,
which may be a little low for the Douglassville area,
and Chloranan at $66.67/ton ($3.00/gal).
Labor Costs
These costs are salaries plus overhead along with
living expenses and some miscellaneous admini-
strative expenses. It is expected that a total of 39
people will be required, with the same number
needed for both the large and small operating units.
It is expected that most of the people will be on
expenses, except for some support people that are
assumed to be local hires.
HAZCON indicated they require three operators plus
one supervisor per shift, with their salaries ranging
from $17.50 to $35.00/hr. It is also assumed that
there is one overall coordinator, which costs the
project $50/hr. In addition, it is assumed that all
personnel are allowed $85/day living expenses.
In order to provide feedstock and other field support
services it is assumed that three operators plus a
supervisor are required each shift plus an overall
coordinator. Expenses for these personnel are
assumed to range from $25/hr for the operators, who
are local hires and do not charge living expenses, to
$40/hr for shift supervisors, and $50/hr for the
coordinator.
In addition, it is assumed there is one site health and
safety officer at $50/hr, an overall project manager at
$60/hr, a part-time sampling technician at $40/hr, an
office manager at $40 far to handle field accounting
and purchasing and one secretary at $20/hr. The
living expenses, with some rental cars included, for
the field support supervisors, field support
Supplies and Consumable Costs
The utilities included are fuel, electricity, water; also
included are byproducts thai; require treatment or
transport to a landfill.
HAZCON indicated that their small mobile field
blending unit (MFU) would, consume fuel for its
operation at 4 gph, and the proposed large unit at 5
gph. External electricity is not required for the MFU.
It is assumed that the support vehicles, front-end
loaders, backhoes, and pick-up truck consume an
equivalent amount of diesel fuel. The fuel was
assumed to cost $1.00/gal. Electricity is assumed to
power lights, trailers, pumps, etc. at an average daily
rate of 5 kw. The cost of electricity is assumed at
$0.04/kwhr.
Water use is primarily for the process, with small
quantities required for equipment decontamination.
Based upon material balances hi the SITE Program
Technology Evaluation Report, the water
consumption is assumed to be 14 gpm for the small
MFU and approximately 100 gpm for the large unit.
The cost of water is assumed at $0.80/1000 gal. There
are not any byproducts from the HAZCON process,
and soil pretreatment or posttreatment is not
necessary. If this were to change due to low pH or
other factors, where neutralization of the untreated
soil feed or special covering of the treated soil
becomes necessary, another major cost could be
added.
23
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Effluent Treatment and Disposal Costs
Since there are not any liquid effluent streams
associated with this technology, no costs accrue to
this category.
Residual and Waste Shipping, Handling, and
Transport Costs
There are no residuals or byproducts associated with
the HAZCON technology. Therefore, there are no
expenses associated with this category of potential
costs. However, if this changes due to the inability of
the site to handle the large volume increase produced
in the treatment of the wastes, a major new expense
for transporting the excesses to an approved landfill
would occur.
Facility Modification, Repair, and Replacement
Costs
The costs accrued under this category include
maintenance and working capital. Maintenance
materials and labor costs are difficult to estimate and
cannot be predicted as functions of preliminary
design concepts. Therefore, annual maintenance
costs are assumed as 10% of capital costs. Working
capital costs are assumed to be negligible, as all
supplies purchased to have on-hand are assumed to
be fully consumed by the project's completion. The
cost of using money early in the project is neglected.
Analytical Costs
It is assumed that sample sets will be taken daily for
the first two weeks of operation at all operating
conditions. After that, sample sets will be collected
once per week until the cleanup is completed. Both
physical and chemical analyses will be run on all
sample sets, with the cost per set estimated at $5,000.
The cost/ton reported in Table 2 is an overall average
value, based upon a completed project.
Site Demobilization Costs
It is assumed that all personnel will be on site for
three days for demobilization. This is sufficient time
for disassembly of the HAZCON mobile equipment,
decontamination and cleanup, but insufficient for
removal of support equipment, storage tanks, pumps,
etc. The additional work required is assumed to be by
the site prime contractor and not charged to
HAZCON.
24
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References
1. Cote, P. 1988. Investigations of Specific
Solidification Processes for the Immobilization
of Organic Contaminants. Wastewater
Technology Center, P.O. Box 5050, Burlington,
Ontario, Canada L7R 4A6, April 27,1988
2. Myers, T. and M. Zappi, 1987. "Laboratory
Investigation of Organic Contaminant
Immobilization by Proprietary Processing of
Basin F Liquid, Rocky Mountain Arsenal,
Denver, Colorado." Technical Report EL-87-11.
U.S. Army Engineer Waterways Experiment
Station, Vicksburg, Mississippi.
3. USEPA, 1987. Sand Springs Superfund Site-
Report Excerpts.
4. USEPA, 1986. Prohibition on the Placement of
Bulk Liquid Hazardous Waste in Landfills-
Statutory Interpretative Guidance. EPA 530-
SW-86/016. U.S. Environmental Protection
Agency, Office of Solid Waste and Emergency
Response, Washington, DC.
5. USEPA, 1982. Guide to the Disposal of
Chemically Stabilized and Solidified Waste.
SW-872 Revised. Municipal Environmental
Research Laboratory, Office of Research and
Development, U.S. Environmental Protection
Agency, Cincinnati, OH.
6. HAZCON Confidential Report B
7. USEPA, 1987. Demonstration Plan HAZCON/
Douglassville SITE Program.
8. USEPA, 1989. Technology Evaluation Report,
Site Program Demonstration Test, Hazcon
Solidification, Douglassville, PA. U.S.
Environmental Protection Agency, Office of
Research and Development, Hazardous Waste
Engineering Research Laboratory, Cincinnati,
OH.
9. Cote, P. and T.R. Bridle, 1987. Long-Term
Leaching Scenarios for Cement-Based Waste
Forms. Waste Management and Research, 1987,
5, pp 55-66.
10. IT Corp. IWC Feasibility Study -
Solidification/Fixation Bench Scale Testing,
Appendix A. IT Corp. Austin, Texas. (no date).
11. HAZCON Confidential Report A
12. Risk Science International, 1987. "Evaluation
of Treatment Technologies for Listed Petroleum
Refinery Wastes. Interim Report." Prepared for
the American Petroleum Institute. April 27,
1987.
13. Planning Research Corporation, 1988.
"Evaluation of Test Protocols for Stabilization/
Solidification Technology Demonstrations."
Draft Report. Contract 68-03-3484. U.S.
Environmental Protection Agency, Office of
Research and Development, Cincinnati, OH.
14. Cote, P., et al., 1986. "An Approach for
Evaluating Long-Term Leachability from
Measurement of Intrinsic Waste Properties."
Hazardous and Industrial Solid Waste Testing
and Disposal, 6th Vol., ASTM STP 933, Dr.
Lorenzen, et al., editors, American Society for
Testing and Materials, Philadelphia, PA, pp 63-
78.
15. U.S. Congress, Office of Technology Assess-
ment, 1988. Are We Cleaning Up? Ten
Superfund Case StudiesA Special Report.
OTA-ITE-362. U.S. Government Printing
Office, Washington, D.C.
25
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APPENDIX A
PROCESS DESCRIPTION
Description of the Primary Treatment
Mechanisms
Solidification and stabilization are treatment
processes that are designed to accomplish one or
more of the folio wing results [1,2]:
Improve the handling and physical charac-
teristics of the waste, as in the sorption of free
liquids.
Decrease the surface area of the waste mass
across which the transfer or loss of contaminants
can occur.
Limit the solubility of any hazardous constitu-
ents of the waste such as by pH adjustment or
sorption [3,4].
Change the chemical form of the hazardous
constituents to render them as innocuous
compounds or make them less leachable.
Solidification entails obtaining these results
primarilyby producing a monolithic block of treated
waste with high structural integrity. Stabilization
techniques limit the mobility of the waste
contaminants or detoxify them, whether or not the
physical characteristics of the waste are changed or
improved. This is accomplished usually through the
addition of materials to ensure that the hazardous
constituents are maintained in their least mobile or
least toxic form [4,5].
The HAZCON process is a cement-based process in
which the contaminated material is mixed with
Portland cement, a patented additive called
Chloranan, and water. The process is capable of
treating solids, sludges, semi-solids, or liquids. The
unit used for the Demonstration Test could only
process solids. The Developer's claim is that the
mixture hardens into a cohesive mass that
immobilizes contaminants. The Chloranan is re-
ported to make it possible to fixate wastes
contaminated with high concentrations of organic
compounds.
The cement hardens in a process brought about by
the interlacing of thin, densely packed silicate fibers
that grow from the individual cement particles. The
fiber matrix incorporates the added aggregates and
the waste into a monolithic, rocklike mass. The
waste soil is entrapped in the rigid matrices of the
hardened concrete. A process; flow diagram of the
HAZCON technology is shown in Figure A-l.
I Pozzolanic
I Additive
(Chloranan
Additive
Figure A-1. HAZCON process flow diagram.
The Chloranan is claimed to act upon the waste to
remove the Figure A-l. HAZCON process flow
diagram, inhibiting effect that organic contaminants
27
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normally have on the crystallization of pozzolanic
materials such as cement, by reacting to form a
coating around the organic molecules. The
microencapsulation prevents the organics from
inhibiting the normal crystallization of the pozzolan.
According to HAZCON, Chloranan is a patented,
proprietary, and nontoxic chemical blend.
Typical ratios of waste/cement on a weight basis
range from 1:1 to 3:1. For the test at the
Douglassville site, a conservative ratio of 1 part
waste to 1 part pozzolan was selected by HAZCON.
Chloranan is pumped into the mixing chamber
followed by the addition of cement. Through precise
control of the flowrate, ratios of waste-to-Chloranan
can be metered accurately from a 10:1 to a 50:1 blend
ratio by weight. For the Demonstration Test, a 10:1
ratio was used. After initial combination of the
primary ingredients, water was added as necessary
to achieve a desirable consistency of the mix as
visually determined by HAZCON.
All additives are fed through a mixing chamber to
achieve a homogenous blend. Various types of mixers
can be used, and the selection may be dependent
upon the type of contaminants.Thorough mixing is
required, particularly when high levels of organics
are present, so that the Chloranan is thoroughly
dispersed into the waste, and then intimately mixed
with the cement and water. A screw blender, used for
the Douglassville test, or a higher energy more
efficient pugmill or ribbon blender may be used. The
resultant mass is discharged into either a temporary
or a permanent disposal area.
Comparison to Existing Treatment
Technologies
Comparing the HAZCON Engineering, Inc. solid-
ification process to other cement-based technologies
reveals that few differences exist in equipment and
still fewer in the processes. Although the means to
convey and mix the materials can vary, the basic
unit operations remain the same. A different type of
cement can be used in the process or a more efficient
mixer to blend the waste, cement, and additive, but
the solidification reactions are essentially the same.
The unique characteristic of the HAZCON process is
the use of the proprietary ingredient Chloranan. The
wastes most effectively solidified by the process are
aqueous solutions, suspensions, or solids containing
appreciable amounts of heavy metals and inorganic
salts. The claimed characteristic of the Chloranan
to inhibit the effects of organics on the crystal-
lization of the cement is unique to the HAZCON
process.
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APPENDIX B
VENDOR'S CLAIMS FOR THE TECHNOLOGY
This appendix to the report is based upon claims
made by HAZCON either in conversations or in
written or published materials. The reader is
cautioned that these claims and interpretation of the
regulations are those made by the vendor and are not
necessarily correct or able to be substantiated by test
data. Many of HAZCON's claims are evaluated in
section 3 against the available test data.
Potential Applicability
The HAZCON Process
The HAZCON mobile field blending units are
capable of treating extracted solids, sludges, or fluids
at rates up to 60 cu yd per hour. These truck- or
trailer-mounted units are supported by bulk cement
carriers and chemical tankers. Two continuous
processing units are currently available; the one
used for the Demonstration Test was sized for 10 cu
yd per hour. This system is not designed to process
fluids.
The HAZCON process is intended primarily for on-
site use at RCRA- and CERCLA-regulated remedi-
ations. Utilization of multiple units of high produc-
tion concrete batching equipment allows treatment
of up to 200 cu yd of waste each hour in high volume
applications.
Materials that are either pumpable, able to be
extracted by earth-moving equipment, or conveyable
using conventional means are most applicable to the
process, because of the ease of introducing the
material into the blending equipment.
HAZCON adapts commonly available conventional
concrete processing equipment to its waste
solidification operations. Truck and trailer systems
are the most convenient, since they are readily
available, but almost any standard mixing
equipment can be used. For large sites, transportable
systems, such as an asphalt batch plant or cement
mixers are appropriate. Batch blending units are the
systems of choice, since, according to HAZCON, feed
variations can be more easily identified. Thus, steps
can be taken to adjust admix ratios to compensate for
feed changes, allowing better control of blending
ratios and mix consistencies. These systems are far
more accurate than the in-line blenders, such as was
used during the SITE demonstration; the in-line
blender was used only because it was most suitable
for a relatively small-scale operation.
HAZCON suggests that their process is superior to
competitive systems such as in situ processes, in that
their excavation and mixing process assures more
effective mixing than in situ systems. Admix
ratioing is more effective and can be better
optimized, whereas in situ systems must use excess
admix materials to ensure proper ratios, leading to
larger volume increases in the product material.
HAZCON makes no claim to a universal treatment
advantage in the use of the chemical blend
Chloranan. Applications of their process where little
or no organic contamination exists would not be
appropriate. The additive has been proven through
extensive internal testing to be capable of producing
a highly leach-resistant product, yielding high
compressive strengths, from highly organic wastes.
HAZCON has the capability of targeting waste-
specific contaminants with the most optimal mix
formulations available, and also has the expertise to
put these formulas to use in actual field applications.
Scale-up from laboratory-sized batches to full-scale
application can be made directly, since the
stabilization chemistry is more significant than the
equipment usedany mechanical equipment that
uniformly mixes the waste and additives is
satisfactory.
HAZCON usually tests all site materials before
operation to determine the proper formulations,
admixes, and ratios for optimum results. Cement-
based mixtures generally ares used, as they have
29
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proven to be effective systems, but the equipment
can process other pozzolanic (fly ash, kiln dust, etc.)
mixtures as well, as needed. HAZCON claims that
optimal results have been achieved using
Chloranan/cement mixes.
Posttreatment is not required. HAZCON also claims
that contaminated clothing and water can be used as
raw materials in the process, and that any materials
that cannot be fed through the system can be
entombed within the solidified mass.
Treatable Wastes
HAZCON claims to be able to handle any type of
feed, such as liquids, sludges, emulsions, and soils.
Only reactive components in the feed may affect the
technology. These components are identified during
laboratory characterization tests, and proper pre-
cautions are taken to keep reactive components
separated, or to pretreat them to nullify their
reactive characteristics. If the laboratory testing
indicates that feed pretreatment can enhance the
solidification process, the waste feed may be pre-
treated as needed. HAZCON stresses that pretreat-
ment usually is not required.
HAZCON reports that the waste types shown in
Table B-l are compatible with their technology. The
waste types listed, found at RCRA and CERCLA
sites, are those for which test data are available.
Additional waste types and contaminants for which
no leachate data are available are also treatable by
the HAZCON process. Matrices preferred by
HAZCON in order of preference are soils, sludges,
emulsions, and lastly liquids, with the preferred
contaminants being metals, organics, and lastly
volatile organics. Additional materials treated by
HAZCON and process results are shown below:
To date the most common full-scale treatment
process performed by HAZCON has been on sludges
containing oil and grease. HAZCON indicates that
they have successfully solidified material for
Monsanto Company, Sterling Chemicals, Phillips
Puerto Rico Core, Inc., Mobil Chemical Co., NALCO
Chemical Co., and others. Laboratory treatment has
been accomplished on all types of refinery, plating,
and blending by-product wastes.
Tablo B-1. Wastes Compatible with the HAZCON System*
Arsenic (6,7)
Barium (5)
Cadmium (6.7,8)
Chromium (3,6,7,8)
Copper (3,8)
Lead (3,7,8)
Mercury (7)
Nickel (6,8)
Selenium (7)
Silver (7,8)
Zinc (8)
Chloroform (9)
Isobutanol (9)
Acrytonitrite (9)
Methyl Ethyl Ketone (MEK) (9)
p&m-CresoJ (3)
Undane(7)
Inden0(3)
Polychlorinated biphenyls (PCBs) (8)
Oil & Grease (8)
BNA Phthalates (3,8)
BNA Phenols (3,8,10)
BNA Naphthalene (3,8)
Methylene Chloride (9)
Pentachlorophenol (PGP) (11)
1,1-Dichloroethylene (9)
1,2-Dichloroben2ene (9)
1,1,1-Trichlorobenzene (9)
1,1,2-Trichloroethane (9)
1,1,1,2-Tetrachloroethane (9)
1,1,2,2-Tetrachloroethane (9)
Bis(2-chloroethyl)ether (10)
2,4-Dimethylphenol (3)
Toxaphene (7)
1-Methylnaphthalene (3)
Toluene (3,8,9)
Trichloroethene (8)
Tetrachloroethane (9)
Ethylbenzene (3,8,9)
Xylenes (3,8)
Benzene (3,9,10)
Trichloroethylene (9,10)
Chloroethylene (9,10)
Tetrachloroethylene (9)
Carbon Tetrachloride (6,9)
Vinyl Chloride (9)
Carbon Disuifide (9)
Acenaphthene (10)
Aniline (10)
o-Cresol (3)
Endrin (7)
2,4-D (7)
Phenanthrene (3)
The numbers in brackets designate references cited.
30
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Material Treated
Nonhazardous organic
sludge
40% aromatic organics
Organic wash-out pit
API separator sludge
Asphaltic sludge, < 1 pH
Slop oil
Oil base paint + solvents
AN centrifuge cake
Acetone
Volume
> 87,000 gal
> 60,000 gal
> 10,000 gal
> 20,000 gal
> 500 gal
> 500 gal
> 250 gal
> 100 gal
> 50 gal
Results
landfillable >300 psi
landfillable >500 psi
landfillable >600 psi
landfillable > 100 psi
nonhazardous, 6.4 pH
landfillable > 1500 psi
landfillable >1500 psi
landfillable >2500 psi
landfillable >1200 psi
Extensive investigations are underway to identify
other wastes that can be treated by the process,
including low-level radioactive wastes.
System Advantages
Some of the claimed advantages of the HAZCON
system over existing systems are:
Formation of a homogeneous mass that is
capable of being emplaced as a unit and is
retrievable, traceable, or useable for other
purposes.
Leach resistance of the product, which can be
accurately measured and recorded.
Creation of a material after treatment that is
transportable without risk of dispersion,
incremental loss in transit, dilution, or mixing
with other materials.
Creation of an extrudable cement-like slurry
that can be formed into any shape and emplaced
in any sort of form or container prior to
hardening to meet a multiplicity of requirements
for disposal, emplacement, or reuse.
Readily available ingredients (fly ash, kiln dust,
Portland cement) except for small quantities of
the proprietary reagent controlled by HAZCON.
Reduction of toxicity immediately upon
hardening, which occurs within 30 minutes of
pouring into forms or containers.
Capability to immediately return the mass to the
blending system for reprocessing in case the mix
is faulty, without degradation of chemical or
physical characteristics.
No necessity to pH-balance waste streams,
allowing the HAZCON system's universal
application.
No need to decant or filter to remove moisture, as
the system has very tolerant allowances for
moisture content, which is utilized in the cement
hydration reactions.
Improved safety as designed, since the HAZCON
extraction and pumping system that carries the
waste to a blending station requires only one
person to be in the exclusion zone in protective
clothingthe remainder of the staff are from
1,000 to 4,000 feet away.
HAZCON has performed in-house laboratory studies
to verify that they can solidify pure acetone into a
homogeneous, strong, and very dense solid free of
volatile gases and practically odorless. As a result of
this capability combined with previous solidification
successes, HAZCON claims that no compounds
known to exist in typical RCJRA and Superfund sites
cannot be treated by their process. Feeds having
solvents, volatiles, or variations in pH or
temperature do not present a problem in the
solidification process. HAZCON presents Table B-2
as indicative of their treatment successes.
Product Characteristics
The prime advantage of the HAZCON organic
fixation technology is in its ability to overcome the
inhibiting effect that organics typically have on
pozzolanic fixation. The additive Chloranan, when
mixed with the waste and cement or kiln dust, reacts
to form a coating around the organic molecules. This
microencapsulation prevents the organics from
inhibiting the normal crystallization of the pozzolan.
Other fixation processes, many of which do not use
proprietary chemicals, cannot claim to treat wastes
with high concentrations of organic material.
The HAZCON solidification process is claimed to
produce a hardened mass with the following
characteristics:
Compressive strengths of 2100 to 5000 psi
Leach resistance
Low permeability (10-7 to 10-9 cm/sec)
More dense than concrete
Volumetric reduction with most wastes or very
small increases
Toxicity reduced
Product available for useful purposes such as
road construction
HAZCON's formulation creates a hardened mass of
sufficient strength for allowing capping even when
applied to wastes containing over 50% total organic
compounds. The most significant capability claimed
31
-------
Table B-2. Priority Pollutant Limits In TCLP Extracts (ppm)
Priority
Pollutant
Arsenic
Barium
Cadmium
Chromium
Lead
Mercury
Selenium
Silver
Benzene
Crosol-o
Cresoi-m
Cresol-p
Endrin
LJndans
Melhoxychlor
Pentachlorophenol
Phenol
Toxaphene
2,4-D
2,4,5-TP Silvex
Toluene
Xytenes-m
Xytones-o
Xytenes-p
1,2-Dtohloroethane
1 ,1 -Dfchtoroethylene
2,4-Dtnitrotoluene
Chtorobenzone
Chlordane
Chloroform
Before
Treatment
11.8
131.0
13.2
68.0
265.0
1.2
2.0
7.5
22.0
>10.8
>10.8
>10.8
1.0
3.0
10.0
70.0
> 14.4
1.0
20.0
10.0
1.0
50.0
51.0
51.0
1.0
> 0.1
> 0.13
> 1.4
> 0.03
> 0.07
Regulatory"
Level
5.0
100.0
1.0
5.0
5.0
0.2
1.0
5.0
0.07
10.0
10.0
10.0
0.003
0.06
1.4
3.6
14.4
0.07
1.4
0.14
14.4
0.4
0.1
0.13
1.4
0.03
0.07
After
Treatment
0.001
0.70
0.28
0.132
0.503
0.0008
0.005
0.038
0.04
0.68
0.66
0.68
0.0004
0.00001
0.00001
1.65
0.67
0.0002
0.00001
0.00001
0.66
0.29
0.34
0.34
0.001
0.0001
0.002
0.00001
0.00001
0.0001
agent ratios required in competitive systems to
fixate high-organic wastes. HAZCON claims that
their lower ratio admix levels also can result in a
lower volume increase of the solidified product than
produced by competitive systems. HAZCON has the
ability to optimize its additive blend to limit volume
increase in situations when volume is of concern. At
the Demonstration site ratios of cement-to-waste of
1:1 and of Chloranan- to-waste of 1:10 were used.
HAZCON claims that ratios as low as 1:3 and 1:20,
respectively, can be used in some applications.
Volume increases as low as 10% have been achieved
in the past on soil wastes; 30% to 40% is average.
Cost Information
HAZCON calculates that the normal cost range for
treatment of one cubic yard of waste varies from
$15.00 to $12 0.00 ($12 to $96/ton of soil), as based on
actual previous bid amounts and completed remedi-
ations. Typically the cost increases as treatment
criteria become more stringent, and according to the
magnitude of difference between the treatment
requirements and the initial condition of the raw
waste.
Capital costs range from $75,000 to $250,000
depending on the output capacity of the blending
equipment. These are typical operating costs:
$100/hour for operators, $3 to $6/ton of soil for
miscellaneous expenses, and $15 to $80/ton of soil for
Jj«i»
additive & .
Overview
HAZCON states that their solidification technology
offers an alternative for on-site remediation of RCRA
and CERCLA sites. The Environmental Protection
"Proposed toxteity characteristic contaminants regulatory levels that
define, using TCLP, if a waste is hazardous - Federal Register
Vol. 51, No. 114 Friday, June 13,1986. [12]
for the solidified product is resistance to leaching of
toxins in excess of the EPA's Maximum Con-
centration Limits (a standard used to evaluate
treatment alternatives as they affect the ability of a
contaminant to pollute the surrounding environ-
ment.)
Once blended, the cement-like slurry can be pumped
into concrete forms for hardening or returned to the
ground for in situ emplacement. The product is
denser than cement; its high strength reduces the
possibility of fracturing and release of toxic com-
ponents.
The addition at normal ratios of the Chloranan
additive is more cost-effective than the higher fixing
Agency evaluation of the HAZCON process under
the Superfund Innovative Technology Evaluation or
SITE program was the first solidification process
evaluation and has provided an abundance of data on
the technology. HAZCON expects that the emerging
data base from the test will set the stage for the
future use of their technology on CERCLA sites
throughout the country.
Under the provisions of the Comprehensive Environ-
mental Response, Compensation, and Liability Act of
1980 (CERCLA) as amended by the Superfund
Amendments and Reauthorization Act of 1986
(SARA), the stabilization/solidification process is
recognized as a Best Demonstrated Available Tech-
nology (BOAT) under the land banning regulations.
The HAZCON process probably can meet Federal
and State applicable or relevant and appropriate
requirements (ARARs) for the disposal of hazardous
wastes.
32
-------
The HAZCON technology has been evaluated and
reported upon at the Douglassville SITE Demon-
stration [8]; in tests reported in the I.T./IWC report
[9]; in two independent confidential studies [6,11]; in
a report by Risk Science International for the
American Petroleum Institute (A.P.I.) [1]; in a
Canadian report [10]; by the Waterways Experiment
Station (WES) at the Rocky Mountain Arsenal [7];
and at the Sand Springs Superfund Site [13].
HAZCON offers these evaluations, the results of
which are highlighted in Section 3 and Appendix A,
as confirmation of their capabilities to remediate a
wide range of sites and contaminants.
33
-------
-------
APPENDIX C
SITE DEMONSTRATION RESULTS
Introduction
A wide variety of soil contaminant concentrations
exist at the Douglassville Superfund Site, and a
variety of feedstocks were used in the tests to
evaluate the HAZCON technology. The soils treated
contained oil and grease ranging from 1% to 25% by
wt, heavy metals (primarily lead) from 0.3% to 2.3%
by wt, volatile organics up to 150 ppm by wt , base
neutral/acid extractables (semivolatile organics)
ranging up to more than 500 ppm by wt, and small
amounts of polychlorinated biphenyls (PCBs). A test
was run on contaminated soil from six plant areas,
each providing a different composition feedstock.
The analytical data consist of test results of
untreated soil, treated soil collected in the field as a
slurry after a 7-day curing period, and core samples
from the solidified blocks after curing in the field for
28 days. Clean soil, FSA soils, and LAN soils, these
two areas containing the highest organics content,
each were mixed in the analytical laboratory with
the cement used in the field without Chloranan and
checked for physical properties as a baseline against
which to compare the field results. The Demon-
stration results are discussed separately in terms of
the physical tests, chemical tests, and operations.
Results
A large amount of analytical and operating data was
obtained, and it was sufficient to meet the program
objectives. The detailed results and operating
summaries are in the Technology Evaluation Report
[8].
Physical
The physical tests showed that the HAZCON process
can readily solidify contaminated soil with oil and
grease content up to 25% by wt. The HAZCON
process produced a structurally firm material, with
few negative properties observed. The unconfined
compressive strengths (UCS) of tested samples
ranged from 220 psi at FSA,, the highest oil and
grease content area, to 1,570 ai; PFA, one of the lower
oil and grease areas. In general, the treated soil
strength was inversely proportional to the oil and
grease content. These UCS values easily meet the
EPA guideline of 50 psi [1.4] for this type of
technology.
Soil samples were prepared in the laboratory without
Chloranan for FSA and LAN. For FSA, the solidified
soil had a UCS of less than 40 psi, while for LAN the
results were equal to those samples with Chloranan.
Therefore, for the highest oil and grease content
samples, Chloranan appears to have a very
beneficial effect.
The permeabilities and other results of the wet/dry
and freeze/thaw weathering tests were good. The
permeabilities, for both the field samples with
Chloranan and the two laboratory formulations
without Chloranan, were in the range of 10-8 to 10-9
cm/sec, which is less than an EPA and industry
guideline of 10-7 cm/sec for hazardous waste landfill
soil barrier liners. Not only dcies a low permeability
reduce contaminant mobility, but it reduces solid
erosion and weathering. The wet/dry and freeze/thaw
weathering tests showed relatively low weight
losses, less than 1.0%, over the twelve cycle tests,
with the test specimen losses only slightly larger
than the control samples, not subjected to drying or
freezing. Unconfined compressive strength tests
performed on the weathered test specimens showed
no losses in strength.
Less positive results were observed from the bulk
density and microstructural analyses. The treated
soil bulkdensity increased approximately 10% to
15% resulting in a volume increase of the treated soil
compared to the untreated soil of 120%. Thus, one
part soil plus one part cement plus water and
Chloranan yields 2.2 parts treated soil by volume.
35
-------
This may provide remediation difficulties involving
where to place the excess material. HAZCON has
indicated that smaller quantities of cement and
Chloranan might have been used, which would
greatly reduce the volume increase, but this may
impact other physical and chemical properties. In
addition, the microstructural analyses showed that
the solidified mass was porous, that mixing of the
various components was not highly efficient, and
that brownish aggregates passed through the process
unchanged. These characteristics are factors that
may impact upon durability of the solid mass and
immobilization of the contaminants. A more efficient
mixer, such as a ribbon blender, may eliminate many
or all of these deficiencies.
The physical properties of the untreated and treated
soils are shown in Tables C-l and C-2.
Chemical
The chemical analysis consists of both soil and
leachate analyses for metals, volatile organics
(VOCs), base neutral/ac id extractables (BNAs), and
polychlorinated biphenyls (PCBs). The leachate
results can be directly related to the corresponding
soil composition.
Table C-3 presents the results for these contam-
inants (except PCBs) in terms of migration potential,
which is defined as the weight of an analyte in the
leachate divided by the weight in the solid being
leached. Migration potential provides a method of
comparing the fraction of an analyte extracted from
the solid for both the untreated and treated soils.
The untreated and treated soil analyses are shown in
Tables C-4 and C-5. The TCLP and special leach
tests, ANS 16.1 and MCC-1P, showed that the
HAZCON process immobilized heavy metals, which
consist predominantly of lead, but not organics. The
heavy metals were reduced in the TCLP leachate
from concentrations of 20 to 50 mg/1 for untreated
soils to 5 to 400 ug/1 for treated soils, with most of the
treated soil values below 100 ug/1. These results are
shown in Table C-6.
The leachate analyses for organics, VOC, and BNA
showed that they were not immobilized, since the
leachate concentrations of the contaminants in the
treated soil were equivalent to those in the untreated
soil (See Tables C-7 and C-8). The primary VOCs
detected were toluene, xylenes, tetrachloroethene,
trichloroethene, and ethylbenzene. The individual
location values for total VOCs varied greatly as the
soil composition ranged from nondetected to a
maximum of 150 ppm by wt at FSA. For the three
areas of lowest VOC concentrations, DSA, LFA, and
PFA, toluene was injected at a rate sufficient to
provide an equivalent of 125 ppm by wt VOC
concentration in these soils. The TCLP leachate
results ranged, for both the treated and untreated
soils, from less than 100 ug/1 to about 1000 ug/1. The
soils without toluene injection provided the best
comparisons.
Table O1. Physical Properties of Untreated Soils
Untreated Soil
Moisture, Bulk density,*3) Oil & Grease.(c)
Plant Area Weight % pH g/ml Weight %
DSA 11.8 6.41 1.23 1.0
LAN 17.6 3.69 1.40 16.5
FSA 24.7 2.56 1.60 25.3
LFA 16.7 4.58 1.68 4.3
PFA 6.6 7.00 1.73 4.5
LAS 11.9 4.11 1.59 7.7
Clean Soil 15.7 6.43 l.63(e) 0.26
Total
Organic Carbon,
Weight %
4.9
23.0
27.3
8.9
7.5
14.3
0.3
Permeability,
cm/sec
5.7x10-1
1.8x10-3
fmpermeable(d)
10.5x10-2"
7.7 x 10-2
1.5x10-5
6.0x10-3
Less than
200 mesh (74n),
%
58
37
NA(d)
57
19
47
32
(a) Values reported are of undisturbed soil samples except for clean soil.
(b) Permeability as measured by constant head permeability test
(c) Oil and grease is fraction of TOO extracted by a solvent
(d) Could not be run due to excessive stickiness.
(o) Compacted loose sand.
36
-------
Table C-2. Physical Properties of Treated Soils
Plant
Area
DSA
LAN
FSA
LFA
PFA
LAS
Cement
only
Clean(f)
soil &
cement
FSA &(W
cement
LAN &
Permeability,
cm/sec
1.8x10-9
3.6 x 10-9
8.4 x 10-8
4.5 x 10-9
5.0x10-9
2.2x10-9
5.9 x 10-9
3.2x10-8
3.8 x 10-8
(a) Permeabilities all performed after 28 days elapsed.
(b) Laboratory formulations prepared without the use of Chloranan: Baseline.
(c) Not scheduled to be performed.
(d) The two low values average 4.7 x 10-10 cm/sec.. The third value was 1.2 X 10-8 cm/sec.
The BNAs consisted of phthalates, phenols, and
naphthalene. The phthalates and naphthalene
concentrations in both untreated and treated soil
TCLP leachates were very low, less than 50 ug/1.
However, the phenol concentrations in the leachates
were much greater. For FSA, where the untreated
soil contained 405 ppm by wt phenols, the untreated
and treated soil leachate concentrations were both in
the range of 3 to 4 mg/1. Thus, for phenols, which
have a moderate solubility in water, the migration
potentials were approximately the same for the
treated and untreated soils. Since the phthalate and
naphthalene leachate concentrations were so low,
determination as to whether they were immobilized
is difficult.
The TCLP leachate analyses for PCBs provided
values all below detection limits of 1.0 ug/1, both for
the treated and untreated soil samples.
The special leach tests, ANS 16.1 and MCC-1P,
attempt to simulate leaching from the solidified
mass, as compared to the TCLP test where the
sample is crushed. Tests equivalent to ANS 16.1 and
MCC-1P were not performed on untreated soil.
Therefore, these results can only be compared to the
treated soil TCLP results. Since experience with
these tests for hazardous wastes is limited, and each
test uses a different weight ratio of solid to leachate,
significance of the results is unclear. However, the
leachate concentrations from all three tests were the
same order of magnitude. This indicates leaching of
the blocks in the field may be similar to that shown
by a TCLP test. This was surprising, since the
surface area and the intimacy of mixing for leaching
in the TCLP test is much greater than for ANS 16.1
andMCC-lP.
Operations
Many operational difficulties were encountered by
HAZCON during the 5-cu-yd runs. Control of
Chloranan and water rates were erratic. In addition,
on two occasions the soil feed screw jammed with
soil, and operations had to be discontinued so the
HAZCON unit could be flushed clean. In the
extended run (3 hr) at LAS, where 25 cu yd of treated
soil was produced, operations ran relatively smooth
with an on-stream factor of about 85%. For all tests a
labor-intensive effort was required to maintain
operations.
Material balances performed on each test run
showed that the soil processing rate ranged from 180
Ib/min to 300 Ib/min and was constant for each test
area. The cement-to-soil additions were maintained
at the targeted ratio of 1:1 except during the
extended run when the cement rate tailed off. The
feed ratio of Chloranan to soil varied between runs,
ranging from 0.052 to 0.094; this compares to the
targeted value of 0.
37
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Table C-3. Migration Potential, ng leached/pg in soiKa>
co
oo
Plant
Area
DSA
LAN
FSA
LFA
PFA
LAS
VOC
Untreated
13.55
0.166
0.137
8.35
4.78
0.154
Treated
5.70
0.285
0.148
0.300
0.730
0.305
Toluene
Untreated Treated
13.55
0.200
0.192
8.35
4.78
0.667
5.97
0.625
0.274
0.312
0.757
0.562
BNAs
Untreated Treated
0.938
0.108
0.0625
0.0519
0.0059
ND
0.617
0.151
NO
0.533
0.306
Phenols
Untreated Treated
ND
3.73
0.139
ND
ND
ND
ND
0.81
0.429
(C)
(C)
1.93
Metals
Untreated
0.0093
0.0691
0.0159
0.0404
0.0567
0.0706
-Pb
Treated
0.000169
0.000036
0.00080
0.000540
0.000061
0.000313
Migration
Reduction
of Lead, %
98.19
99.95
95.03
98.67
99.89
99.56
(a) Based upon TCLP leaching test.
(b) ND - Not detected.
(c) Below quantification limits.
-------
Table C-4. Chemical Analyses of Untreated Soils
Parameter DSA LAN
FSA
LFA
PFA
LAS
PCBs ppm bv wt
Aroclor 1 260
Aroclor 1248
Oil and grease, % by wt
Metals ppm bv wt
Lead
Chromium
Nickel
Cadmium
Copper
Zinc
BNA - DDb bv wt
All phthalates
All phenols
Naphthalene
Volatiles - ppb bv wt
Toluene
Trichloroethene
Tetrachloroethane
Ethyl benzene
Xylenes
1.2
ND
0.98
3,230
24
23
1
74
315
12,150
ND
ND
ND
ND
ND
ND
ND
51
ND
16.5
9,250
19
6
2.3
35
150
15,700
5,200
ND
1,000
130
160
180
970
40
ND
25.3
22,600
31
8
6
128
655
14,200
405,000
115,000
26,000
13,800
6,100
13,000
91,000
10
ND
4.27
13,670
46
22
4
90
735
33,500
ND
3,200
ND
ND
ND
ND
ND
14.5
19
4.47
7,930
95
46
5.5
440
1,600
10,750
ND
7,700
ND
ND
100
ND
320
250
270
7.800
14,8300
730
170
3.50
1400
5800
34,2000
NDO
5,4000
2900
5800
1,500
400
3,700
ND None detected
Table C-5. Chemical Analyses of Treated Soils*
Parameter DSA LAN
"Based on 28-day results
FSA
LFA
PFA
LAS
Total PCBs (ppm)
Oil and grease (%)
Lead (ppm)
Total BNAs (ppb)
Phthalates
Phenols
Naphthalene
Total Volatiles (ppb)
Toluene (ppb)
0.54
830
ND
ND
ND
ND
1320
1240
7.54
2800
42800
ND
32400
10400
3550
1280
9.45
10300
368900
1300
126800
216700
105300
19000
1.53
1860
ND
ND
ND
ND
24700
23700
2.11
3280
4130
ND
ND
4130
22700
17700
1.67
3200
15700
2150
6700
4550
7200
1780
39
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Table C-6. Concentration of Metals in TCLP Leachates mg/liter*
Pb Cr Ni
Cd
Cu
Zn
Soil
DSA
LAN
FSA
LFA
PKA
LAS
7-Dav Cores
DSA
LAN
FSA
LFA
PFA
LAS
28-Day Cores
DSA
LAN
FSA
LFA
PFA
LAS
1.5
31.8
17.9
27.7
22.4
52.6
0.015
< 0.002
0.07
0.04
0.01
0.14
0.007
0.005
0.400
0.050
0.011
0.051
< 0.008
< 0.008
0.27
< 0.008
< 0.008
< 0.008
<0.07
<0.07
0.02
<0.07
<0.07
< 0.008
< 0.007
0.007
< 0.070
0.009
< 0.007
0.015
0.02
0.07
0.11
0.06
0.05
0.07
<0.15
<0.15
< 0.008
<0.15
<0.15
< 0.008
t-
0.020
< 0.01 5
<0.15
0.015
< 0.01 5
0.025
< 0.004
0.02
0.13
0.03
0.01
0.04
<0.04
<0.04
< 0.003
<0.04
<0.04
< 0.003
< 0.004
< 0.004
< 0.040
< 0.004
< 0.004
< 0.004
<0.03
<0.3
<0.03
<0.08
<0.03
0.13
<0.06
<0.06
<0.03
<0.06
<0.06
<0.05
0.023
0.010
< 0.060
0.080
0.027
0.055
0.07
1.1
23.0
6.7
1.4
4.8
<0.02
<0.02
0.02
0.04
0.02
0.04
0.037
0.017
0.037
0.013
0.030
0.258
1 Where the symbol < is used, indicates values below detection limits of quantity shown. The detection limits vary between metals and from
WhereS2 of^3 vafues are above detection limits, three values were averaged assuming the one below detection limits is zero. If only one of
three values is above detection limits, the results are reported as below detection limits.
Tabto C-7. Volatiles In TCLP Leachates, pg/IO)
Volatile Organic DSA LAN
FSA
LFA
PFA
LAS
Untreated Soil
Toluene
Xytenes
Trichloroethene
Tetrachtoroethene
Ethyl benzene
7-Dav Cores
Toluene
Xylenes
Trichloroethene
Tetrachtoroethene
Ethyl benzene
28-Dav Cores
Toluene
Xylenes
Trichloroethene
Tetrachtoroethene
Ethyl benzene
915
<50
<20
<40
<70
380
3.5
<10
<20
<40
370
6
<9
<6
<3
10
7
2.4
<4
<7
<6
6
<2
<4
<7
40
8
2
3
2
245
525
165
19
80
220
340
105
11
60
230
330
100
20
60
5100
<230
<95
<210
<360
201
5
<2
<4
<7
370
<6
<9
<6
2
11000)
<180
<76
<160
<290
350
20
<5
<10
<20
670
170
<9
<6
<3
10
35
8
5
<7
<15
15
<5
<10
<20
50
40
8
10
4
(a) < indicates less than detection limits. Within one sampling area, the detection limit may change between samples. For these, the highest
detection limit is shown.
(b)Two values < 60 and 2200 ug/1.
40
-------
Table C-8. Base Neutral/acid Extractables in TCLP Leachates, pg/l
SNA DSA LAN FSA
LFA
PFA
LAS
Untreated Soil
Phthalates
Phenols
Naphthalene
7-Dav Cores
Phthalates
Phenols
Naphthalene
28-Dav Cores
Phthalates
Phenols
Naphthalene
ND
ND
ND
NO
40
15
ND
ND
ND
10
1010
ND
30
1310
ND
10
1440
ND
ND
2810
50
ND
3850
60
10
2720
60
10
ND
ND
10
30
10
20
80
ND
10
ND
ND
20
50
20
30
80
ND
ND
ND
10
ND
470
ND
80
650
ND
Mfi ,, nrvf Ho+Af-ttnrl
41
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Appendix D
Case Studies
Data in the HAZCON Applications Analysis Report was quoted from a variety of
outside sources along with the SITE Technology Evaluation Report. This Appendix
contains a summary of these sources, listed below.
D-l
D-2
D-3
D-4
D-5
D-6
D-7
Canadian Report [10]
Waterways Experiment Station - Basin F Liquid Rocky Mountain Arsenal [7]
Sand Springs Superfund Site [13]
Risk Science International for API [3]
IT Study for IWC [9]
HAZCON Confidential Report A [11]
HAZCON Confidential Report b [6]
43
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Case Study D-1
Canadian Report: Investigation of Specific
Solidification Processes for the Immobilization of
Organic Contaminants.
Description:
A laboratory study was conducted on the
effectiveness of the HAZCON solidification process
on a spiked metal finishing waste. Acenaphthene,
aniline, benzene, bis(2-chloroethyl) ether, phenol,
trichloroethylene and lithium (as a tracer) were
added to create a concentration of 500
micrograms/gram in the waste. Two hundred grams
of Chloranan and 2,000 grams of Portland cement
was added to the 2,000 gram waste sample (1:1 and
1:10 ratios, respectively). Mixing was limited to 10
minutes.
Testing Protocol:
After 56 days of curing chemical and physical tests
were performed on the sample. The untreated sample
had been previously tested with certain of these same
tests. The conclusions section lists the specific tests
and the results, and the data comparison. Two
replicate samples were tested and the data reported.
No effort was made to control or contain chemical
volatilization during the mixing and curing.
The leach concentration was measured in a batch
extraction conducted for 7 days at a liquid-to-solid
ratio of 4:1. The liquid-to-solid ratio is calculated on a
dry weight basis but the waste is added wet.
Major Conclusions:
No conclusions are presented in the document.
Data Summary
Measured Physical Properties
bulk density of untreated
waste (gm/cm3)
bulk density of treated waste
(gm/cm3)
solids specific gravity (@ 20
C)
moisture content (w/ww)
unconfined compressive
strength (kPa)
freeze/thaw weathering
(weight loss)
permeability (m/s X
10E + 10,@20C)
Weight and Volume Changes
weight change factor
volume change factor
Calculated Matrix Properties
void fraction
porosity
degree of saturation
1.49
1.84
2.263
0.188
20,409
-0.0082
4
2.26
1.83
0.51
0.34
1.02
44
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Equilibrium Leach Test Summary
Concentration
Measured Calculated
Rep Contaminant Name Leachate (ug/ml) Residue (ug/g)
1 Acenaphthene
Aniline
Benzene
Bis(2-chloroethyl)ether
Lithium
Phenol
Trichloroethylene
2 Acenaphthene
Aniline
Benzene
Bis(2-chloroethyl)ether
Lithium
Phenol
Trichloroethylene
1.820
19.400
0.007
2.110
66.000
49.500
0.003
1.650
19.300
0.009
2.240
67.000
52.120
0.010
211.7
154.2
221.0
213.7
-8.2
50.6
221.0
212.3
154.6
221.0
213.3
-11.6
41.6
221.0
Calculated
Fraction
Extracted (%)
2.9
30.2
0.0
3.3
103.8
77.1
0.0
2.6
30.1
0.0
3.5
105.3
81.2
0.0
ANS16.1 Leachate Index
Contaminant
LX
Aniline
Bis(2-chloroethyl) ether
Phenol
Acenaphthene
Lithium
8.2
9.9
7.9
10.1
7.0
45
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Case Study D-2
Laboratory Investigation of Organic Contaminant
Immobilization by Proprietary Processing of Basin F
Liquid; Rocky Mountain Arsenal, Denver, Colorado.
Description:
A laboratory study was conducted on the
effectiveness of the HAZCON solidification process
on the Basin F liquid from the Rocky Mountain
Arsenal. Basin F is a hazardous waste
storage/evaporation pond containing several million
gallons of chemical waste from past industrial and
military activities. Concentrations reported were
TOG 97,000 mg/1; ammonia-nitrogen 40,700 mg/1;
copper 5,860 mg/1; and arsenic 3.10 mg/1. The pH of
the liquid was 5.7.
To 1,500 grams of Basin F liquid was added 3,500
grams of portland cement (1:2 ratio) and 500 grams of
Chloranan (3:1 ratio). During mixing ammonia gas
was released; it was determined this could be avoided
by adding magnesium and phosphate to form
ammonium magnesium phosphate.
Testing Protocol:
Physical and Chemical tests were performed on the
stabilized waste. The physical test was the
unconfined compressive strength (UCS) procedure.
Six duplicate samples were tested and the results
averaged. Two chemical tests were used to evaluate
the stabilization effectiveness; the toxicity extraction
procedure (EP) and the sequential batch leach test
(SBLT). Two duplicate samples were run with the EP
tox and four samples were tested using SBLT.
Leachates generated by the EP tox and the SBLT
were analyzed for TOG, copper, barium, cadmium,
chromium, lead and silver, selenium, mercury,
ammonia and pesticides (e.g., lindane, endrin, and
toxaphene).
Major Conclusions:
Physical strength tests showed that the HAZCON
process can convert Basin F liquid to a hardened solid
mass. Sequential batch leach tests showed that
greater than 86 percent of the total organic carbon
could be leached from HAZCON solidified Basin F
liquid. The Toxicity Extraction Procedure showed
that HAZCON solidified Basin F liquid did not
exceed the limits for the contaminants specified by
the USEPA for the procedure.
The HAZCON solidification process is a cement-
based process that possesses chemical stabilization
properties similar to other cement-based
solidification processes. The HAZCON process did
not effectively stabilize the total organic carbon in
Basin F liquid. Chemical stabilization of organics in
Basin F liquid by the HAZCON process did not
appear technically feasible.
Data Summary:
The unconfined compressive (UCS) strength test
results were dependent on the curing period. After
curing for seven days the UCS was less than 500 psi,
but the UCS increased rapidly to 2,900 psi after 30
days of curing. There was potential for further
strength development.
To pass the toxicity extraction procedure the leachate
must not exceed concentrations one hundred times
the national interim primary drinking water
standards. In all cases, for the specific compounds
analyzed for, the leachate concentrations were
substantially below the requirements.
There are five sequential leachates developed from
the sequential batch leach test. In the first step 67.2%
of the TOG was leached from the HAZCON stabilized
waste. For steps 2 through 5, the cumulative TOC
extracted were 79.6, 83.7, 85.4 and 86.7 percent,
respectively. Further leaching would have removed
more TOC. Thus, less than 13 % of the TOC was
resistant to leaching after the HAZCON treatment.
46
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Case Study D-3
Sand Springs Superfund Site Test Summary.
Description:
A field treatability study was performed at the Sand
Spring, Oklahoma Superfund Site located about 10
miles west of Tulsa. HAZCON used their Mobile
Field Blending Unit to process waste from a closed oil
refinery. The waste was a heavy organic tar (about
50% organics) with little volatile organics. Three
samples of the raw material were analyzed and two
samples of the treated (stabilized) waste. The before
and after results were compared to determine if there
had been any improvement in the leaching
characteristics.
Testing Protocol:
Both physical and chemical tests were performed on
the treated waste. Only chemical tests were
performed on the untreated waste. Physical tests
included the unconfined compressive strength (UCS),
the wet/dry durability and permeability. Chemical
test was the Toxic Characteristic Leaching Procedure
(TCLP).
The leachates (before and after) were analyzed for
both organics and metals. The organic analysis
included volatile organics (i.e., benzene, ethyl ben-
zene, toluene, total xylenes 2-hexanone and 4-
methyl-2-pentanone) and semivolatile organics (i.e.,
2-methlyphenol, 2,4-dimethlyphenol, naphthalene,
2-methylnaphthalene, phenanthrene and flour-
anthene). Most metals were included in the metals
analysis.
Major Conclusions:
No conclusions were presented in the document.
Data Summary:
The physical test results were very good. The UCS
data ranged from 450 psi to 600 psi. Weight loss from
the wet/dry durability test ranged from 0.09 to 0.12%
after 4 cycles. The permeability data was not
available.
After treatment only barium and zinc had TCLP
leachate concentrations that could be quantified and
these were at the detection limits. All the other
metals were below the detection limits. Many of the
metals had TCLP leachate concentrations below the
detection limits before treatment, i.e., arsenic,
barium, beryllium, cadmium, mercury, selenium,
silver and thallium.
After treatment the leachate concentrations for all
the volatile and semivolatile organics (listed above)
were below the detection limits. Three volatile
organics were not detected in leachate from the
untreated waste (i.e., benzene, ethyl benzene and 4-
methyl-2-pentanone). Those organics that could be
measured had leachate concentrations less than 0.01
mg/1 from the untreated waste.
47
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Case Study D-4
Risk Science International for American Petroleum
Institute: Evaluation of Treatment Technologies for
Listed Petroleum Refinery Wastes
Description:
A laboratory study was performed to determine if the
HAZCON stabilization process can adequately treat
refinery waste, i.e, API separator sludge, slop oil
emulsion solids, plate filter cake and belt filter cake.
Chloranan was mixed with 50 gram samples of each
waste at ratios of 1:10, 1:20 and 1:30. The best mix
was then further mixed with pozzolanic material
(e.g., kiln dust) at ratios of 1:1, 2:1 and 3:1. There is
no information as to whether any effort was made to
contain the volatile organics from volatilizing. The
TCLP leachate concentration for the untreated waste
was compared to the leachate concentration for the
stabilized waste and a percent reduction in
concentration calculated.
Testing Protocol:
After curing 24 hours the sample was tested for pH,
compressive strength and wet/dry durability. The
leacnates were analyzed for volatile, semivolatile
(base/neutral) and acid organics, and metals. Volatile
organics included benzene, methyl ethyl ketone,
styrene, ethylbenzene, toluene and xylenes.
Semivolatile organics included anthracene, chrysene,
indene, fluoranthene, naphthalene, phenanthrene,
pyrene and several other BNAs. Acid organics
included cresol, 2,4-demethylphenol and phenol.
Metals included arsenic, barium, cadmium,
chromium, cobalt, lead, mercury and selenium.
Major Conclusions:
No conclusions were presented in the document.
Data Summary:
After HAZCON treated the API separator sludge a
substantial reduction in the leachate concentrations
was measured. For those chemicals that the change
in leachate concentration could be measured, the
leachate concentration reduction ranged from 96 to
99%. This was true for all four chemical classes;
VOCs, BNAs, acid organics and metals.
The results of the stabilization of the slop oil
emulsion solids was less successful. Volatile organic
leachate concentration dropped by 99%, but the
BNAs showed little if any change and there was an
increase in the leachate concentration of the acid
organics. Most metals were below detectable limits
before and after treatment.
The effectiveness of the HAZCON stabilization
process on the plate filter cake and belt filter cake
could not be determined because most of the
chemicals were below detectable limits before
treatment.
48
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Case Study D-5
International Technologies Study for the IWC
Superfund Site.
Description:
A laboratory study was conducted on the
effectiveness of the HAZCON solidification process to
treat the two wastes at the IWC superfund site.
Wastes from the surface impoundment and the Area
D drum solvent were prepared into three samples for
treatment. These samples were surface
impoundment sludge; surface impoundment sludge
mixed with the aqueous phase from Area D; and
surface impoundment sludge mixed with both the
aqueous and organic fractions from Area D.
The surface impoundment contaminants were
toluene - 72,000 ppm, trichloroethylene - 21,000 ppm
and ethyl benzene - 3,000 ppm. Area D drum disposal
had toluene - 92,000 ppm, ethyl benzene - 39,000
ppm, methylene chloride - 83 ppm, and
trichloroethylene and tetrachloroethylene less than
50 ppm. (To the 300 grams of sludge and 100 grams of
mixed liquids, HAZCON mixed in 60 grams of
Chloranan and 300 grams of Portland cement. The
TCLP leachate concentrations were compared to the
treated TCLP concentrations before treatment and to
the proposed TCLP limits.
Testing Protocol:
The samples were tested for physical properties using
the unconfined compressive strength (UCS)
procedure. Chemical properties of the samples were
determined by the toxic leaching characterization
procedure (TCLP). The TCLP leachate was analyzed
for a broader range of chemicals than listed above.
The testing procedure did not attempt to suppress the
loss of volatile organics during the mixing and curing
of the samples.
Major Conclusions:
The data derived from the HA2ICON bench scale test
demonstrates that the waste soils, sludges, aqueous
liquids and organic liquids present at the IWC site
may be successfully treated by solidification arid
fixation for on-site disposal.
The general conclusions were that HAZCON
"passed" the metal and extractable organics (BNAs)
leach test for surface impoundment sludge mixed
with both the aqueous liquid and the two fractions
from Area D (sample types 2 and 3). HAZCON also
"passed" the volatile organic leach test for the
aqueous mix, but only had a "tentative" pass for the
two fraction mix. A passing concentration is a
leachate concentration less than the proposed TCLP
limits. BNAs have no proposed TCLP limits and thus
substantial reduction in leacha.te concentration was
used to determine "passing."
Data Summary:
UCS results for the two HAZCON samples improved
over the curing period from 200 and 225 psi after 18
hours of curing to greater than 700 psi after 90 hours
of cur ing.
The TCLP results for volatile organics were mixed.
For most chemicals the TCLP results were below the
proposed TCLP limits. There were a few chemicals,
however, that the detection limits were above the
proposed limits and when the leachate data was
reported as "less than the detection limit" it is
difficult to interpret the data. Chemicals of this type
were benzene, carbon tetrachloride, methyl ethyl
ketone, chloroform, isobutanol, trichloroethylene,
vinyl chloride and tetrachloroethylene. Except for
isobutanol, the leachate concentrations for the above
chemicals were all less than 10 mg/1 and most were
less than 1 mg/1.
49
-------
Case Study D-6
HAZCON Confidential Report A.
Description:
Waste samples from five plant facilities were
obtained and laboratory treatability studies
performed. These wastes contained chromium,
chlorobenzene, cadmium, nickel and arsenic.
Testing Protocol:
For each of the five wastes duplicate samples were
treated using the HAZCON solidification procedure
and allowed to cure for 32 to 56 days.
No physical test results were reported. Chemical test
results were determined by performing the toxic
characteristic leaching procedure (TCLP) and
analyzing the leachate for the compound of interest.
For two of the facilities (B and E) the raw (untreated)
waste was also tested with the TCLP. Method blanks
were performed.
Major Conclusions:
No conclusions are presented in the document.
Data Summary:
Results of the TCLP Analyses for the HAZCON 28-day samples:
Plant
A
B
C
D
E
Sample
1
2
Methods Blank -
1
2
raw waste
Methods Blank -
1
2
Methods Blank -
.1
2
Methods Blank -
1
2
raw waste
Methods Blank -
Constituent
chromium
chromium
chromium
chlorobenzene
chlorobenzene
chlorobenzene
chlorobenzene
cadmium
cadmium
cadmium
nickel
nickel
nickel
arsenic
arsenic
arsenic
arsenic
Concentration
men
0.032
0.030
<0.02
0.6
1.4
33.0
< 0.005
0.05
<0.02
<0.02
0.06
0.07
<0.05
0.91
0.67
30
<0.01
Proposed
Regulatory
Level, mg/1
5.0
5.0
1.4
1.4
1.4
1.0
1.0
4.8
4.8
5.0
5.0
5.0
Proposed regulator level from the 6/13/86 Federal Register
Nickel estimated delisting criteria; 5/17/88 Federal Register proposed regulation shows 0.31 mg/1
50
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Case Study D-7
HAZCON Confidential Report B.
Description:
A laboratory study was conducted on the
effectiveness of the HAZCON solidification process
on soil contaminated with pentachlorophenol (PCP).
The results of the TCLP on the raw waste was 2.1
ppm PCP. No information was available on the
mixing ratios of cement or Chloranan.
Testing Protocol:
Nine treatability samples were processed by
HAZCON. After curing, a toxic characteristic
leaching procedure (TCLP) was performed on the
samples and the leachate analyzed for PCP.
Major Conclusions:
No conclusions are presented in the available
information.
Data Summary:
Below is the TCLP data on the nine treatability
samples:
Sample Number
PCP TCLP
Concentration
mg/1
9
10
11
12
13
14
15
16
17
16
21
24
26
24
4.3
2.9
27
1.1
51
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References for Appendices
1. Tittlebaum, M.E., et al. State-of-the-Art on
Stabilization of Hazardous Organic Liquid
Wastes and Sludges. In CRC Critical Reviews in
Environmental Control, Vol. 15, Issue 2, CRC
Press, Boca Raton, Florida, 1985, pp 179 - 211.
2. USEPA, 1985. HandbookRemedial Action at
Waste Disposal Sites. EPA 625/6-85/006. U.S.
Environmental Protection Agency, Office of
Research and Development, Cincinnati, Ohio,
and Office of Solid Waste and Emergency
Response, Washington, B.C.
3. Risk Science International, 1987. "Evaluation
of Treatment Technologies for Listed Petroleum
Wastes." Interim Report. Prepared for the
American Petroleum Institute. April 27,1987.
4. USEPA, 1982. Guide to the Disposal of
Chemically Stabilized and Solidified Waste.
SW-872 Revised. Municipal Environmental
Research Laboratory, Office of Research and
Development, U.S. Environmental Protection
Agency, Cincinnati, Ohio.
5. Malone, P.G. and L. Jones, 1979. Survey of
Solidification/Stabilization Technology for
Hazardous Industrial Wastes. EPA 600/2-
79/056. U.S. Environmental Protection Agency,
Municipal Environmental Research
Laboratory, Cincinnati, Ohio.
6. HAZCON Confidential Report B.
7. Myers, T. and M. Zappi, 1987. "Laboratory
Investigation of Organic Contaminant
Immobilization by Proprietary Processing of
Basin F Liquid, Rocky Mountain Arsenal,
Denver, Colorado." Technical Report EL-87-11.
U.S. Army Engineer Waterways Experiment
Station, Vicksburg, Mississippi.
8. USEPA, 1988. Technology Evaluation Report,
SITE Program Demonstration Test, HAZCON
Solidification, Douglassville, PA. U.S.
Environmental Protection Agency, Office of
Research and Development, Risk Reduction
Engineering Laboratory, Cincinnati, Ohio.
9. IT Corp. IWC Feasibility Study - Solidi-
fication/Fixation Bench Scale Testing, Appendix
A. IT Corp. Austin, Texas, (no date).
10. Cote, P. 1988. Investigation of Specific
Solidification Processes for the Immobilization
of Organic Contaminants. HAZCON, Inc.
Wastewater Technology Center, P.O. Box 5050,
Burlington, Ontario L7R 4A6, April 27,1988.
11. HAZCON Confidential Report A.
12. Federal Register, Volume 51, No. 114, 6/13/86,
p. 21652.
13. USEPA, 1987. Sand Springs Superfund Site -
Report Excerpts.
14. USEPA, 1986. Prohibition on the Placement of
Bulk Liquid Hazardous Waste in Landfills
Statutory Interpretative Guidance. EPA 530-
SW-86/016. U.S. Environmental Protection
Agency, Office of Solid Waste and Emergency
Response, Washington, D.C.
52
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