EPA/540/R-94/520
March 1995
Geosafe Corporation In Situ Vitrification
INNOVATIVE TECHNOLOGY EVALUATION REPORT
Risk Reduction Engineering Laboratory
Office of Research and Development
U.S. Environmental Protection Agency
Cincinnati, Ohio 45268
on Recycled Paper
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NOTICE
The information in this document has been prepared for the U.S. Environmental Protection Agency's
(EPA's) Superfund Innovative Technology Evaluation (SITE) Program under Contract No. 68-CO-0048.
This document has been subjected to EPA's peer and administrative reviews and has been approved for
publication as an EPA document. Mention of trade names of commercial products does not constitute
an endorsement or recommendation for use.
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FOREWORD
The Superfund Innovative Technology Evaluation (SITE) Program was authorized by the Superfund
Amendments and Reauthorization Act (SARA) of 1986. The Program is administered by the EPA Office
of Research and Development (ORD). The purpose of the SITE Program is to accelerate the development
and use of innovative cleanup technologies applicable to Superfund and other hazardous waste sites. This
purpose is accomplished through technology demonstrations designed to provide performance and cost
data on selected technologies.
This project consisted of a demonstration conducted under the SITE Program to evaluate the In Situ
Vitrification Technology developed by the Battelle Memorial Institute and exclusively licensed to Geosafe
Corporation for treatment of soils contaminated with organic and inorganic materials. The Battelle
Memorial Institute developed the ISV technology for the U.S. Department of Energy, Environmental
Management Division, Office of Technology Develpment at Pacific Northwest Laboratory. The
technology Demonstration was conducted at the former site of Parsons Chemical Works, Inc. in Grand
Ledge, Michigan. This Innovative Technology Evaluation Report presents an interpretation of the
performance and cost data gathered during the demonstration and discusses the potential applicability of
the technology.
A limited number of copies of this report will be available at no charge from the EPA's Center for
Environmental Research Information, 26 West Martin Luther King Drive, Cincinnati, Ohio, 45268.
Requests should include the EPA document number found on the report's cover. When the limited supply
is exhausted, additional copies can be purchased from the National Technical Information Service (NTIS),
Ravensworth Building, Springfield, Virginia, 22161, (703) 487-4600. Reference copies will be available
at EPA libraries in the Hazardous Waste Collection. You can also call the SITE Clearinghouse Hotline
at (800) 424-9346 or (202) 382-3000 in Washington, D.C. to inquire about the availability of other
reports.
E. Timothy Oppelt, Director
Risk Reduction Engineering Laboratory
111
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ABSTRACT
The Geosafe In Situ Vitrification (ISV) Technology is designed to treat soils, sludges,
sediments, and mine tailings contaminated with organic, inorganic, and radioactive compounds. The
organic compounds are pyrolyzed and reduced to simple gases which are collected under a treatment
hood and processed prior to their emission to the atmosphere. Inorganic and radioactive contaminants
are incorporated into the molten soil which solidifies to a vitrified mass similar to volcanic obsidian.
This mobile technology was evaluated under the SITE Program on approximately 330 yd3 of
contaminated soil at the Parsons site. Demonstration results indicate that the cleanup levels specified
by EPA Region V were met and that the vitrified soil did not exhibit teachability characteristics in
excess of regulatory guidelines. Process emissions were also within regulatory limits.
The Geosafe ISV Technology was evaluated based on seven criteria used for decision-making
in the Superfund Feasibility Study (FS) process.
This report was submitted in fulfillment of Contract No. 68-CO-0048 by SAIC under the
sponsorship of the U.S. Environmental Protection Agency. This report covers a period from March
1994 to April 1994, and work was completed as of April 1994.
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TABLE OF CONTENTS
Page
NOTICE • "
FOREWORD i'i
ABSTRACT lv
LIST OF TABLES ™
LIST OF FIGURES lx
ACRONYMS, ABBREVIATIONS, AND SYMBOLS x
CONVERSIONS x111
ACKNOWLEDGEMENTS
EXECUTIVE SUMMARY . !
SECTION 1 INTRODUCTION . 7
1.1 Background -7
1.2 Brief Description of Program and Reports 8
1.3 The SITE Demonstration Program 9
1.4 Purpose of the Innovative Technology Evaluation Report '10
1.5 Brief Technology Description 10
1.6 Key Contacts 11
SECTION 2 TECHNOLOGY APPLICATIONS ANALYSIS 13
2.1 Key Features '13
2.2 Operability of the Technology '14
2.3 Applicable Wastes ,15
2.4 Availability and Transportability of the Equipment , '17
2.5 Materials Handling Requirements '18
2.6 Site Support Requirements '18
2.7 Ranges of Suitable Site Characteristics '19
2.8 Limitations of the Technology '21
2.9 ARARS for the Geosafe ISV Technology 22
2.9.1 Comprehensive Environmental Response, Compensation and Liability
Act(CERCLA) .23
2.9.2 Resource Conservation and Recovery Act (RCRA) • 27
2.9.3 Clean Air Act (CAA) , 29
2.9.4 Clean Water Act (CWA) . 29
2.9.5 Safe Drinking Water Act (SDWA) • 30
2.9.6 Toxic Substances Control Act (TSCA) • 30
2.9.7 Occupational Safety and Health Administration (OSHA)
Requirements -31
2.9.8 State Requirements 32
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TABLE OF CONTENTS (Continued)
SECTION 3 ECONOMIC ANALYSIS .
Page
33
3.1 Conclusions and Results of the Economic Analysis ... 33
3.2 Issues and Assumptions .................. ... 39
3.3 Basis of Economic Analysis ............... ... 42
3.3.1 Site and Facility Preparation Costs ................... ' ...... 43
3.3.2 Permitting and Regulatory Requirements Costs ................. 44
3.3.3 Equipment Costs .................................... 45
3.3.4 Start-up and Fixed Costs ....... ........................ 47
3.3.5 Labor Costs ....................................... 48
3.3.6 Consumables and Supplies Costs .......................... 49
3.3.7 Utilities Costs ...................................... 51
3.3.8 Effluent Treatment and Disposal Costs ....................... 52
3.3.9 Residuals and Waste Shipping and Handling Costs ............... 53
3.3.10 Analytical Service Costs ................................ 54
3.3.11 Maintenance and Modifications Costs ....................... 55
3.3.12 Site Demobilization Costs ............................... 56
SECTION 4 TREATMENT EFFECTIVENESS 57
4.1 Site History and Contamination ................................ 57
4.2 Treatment Approach ....................................... 57
4.3 Treatment Objectives ....................................... 59
4.4 Detailed Process Description 59
4.5 Testing Methodology ...................... : ............... 65
4.6 Perfomance Data ......................................... 71
Test Soil ...... 71
4.6.1.1 Pre-Treatment Test Soil Chemical Characteristics ..... 71
4.6.1.2 Post-Treatment Test Soil Chemical Characteristics ..... 77
4.6.1.3 Pre-Treatment Test Soil Physical Characteristics ....... 79
4.6.1.4 Post-Treatment Test Soil Physical Characteristics ...... 79
Scrubber Liquor ................ , . . . . . . 80
4.6.2.1 Pre-Treatment Scrubber Liquor ................. 80
4.6.2.2 Scrubber Liquor During and After Treatment ........ 84
4.6.3 Stack Gas ........................................ 85
4.6.4 Limitations of the Data Results .......................... 88
4.6.5 Process Operability and Performance at the Parsons Site .......... 90
4.7 Process Residuals
95
Vi
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TABLE OF CONTENTS (Continued)
Section 2^
SECTION 5 OTHER TECHNOLOGY REQUIREMENTS "
5.1 Environmental Regulation Requirements 99
5.2 Personnel Issues 100
5.3 Community Acceptance 100
SECTION 6 TECHNOLOGY STATUS 102
6.1 Previous/Other Experience 102
6.2 Scaling Capabilities .... HO
REFERENCES m
APPENDIX A VENDOR'S CLAIMS 113
A.I Summary us
A.2 Introduction 114
A.3 Applicability to Contaminated Soil and Other Earth-Like Materials 115
A.4 Application Configurations 116
A.5 Contaminant Treatment Effectiveness and Permanence 116
A.6 Residual Vitrified Product 118
A.7 Air Emissions and Other ARARs 119
A.8 Application Limitations 119
A. 8.1 Media Melting Characteristics 119
A. 8.2 Vitrified Product Quality ... 120
A. 8.3 Water Recharge 120
A.8.4 Processing Depth 121
A.8.5 Total Organic Content 121
A.8.6 Debris Content 122
A.8.7 Sealed Containers 122
A. 8.8 Media Gas-Phase Permeability 123
A.9 cost 123
A. 10 Regulatory and Public Acceptance 124
A. 11 Development Status and Commercial Implementability 125
A. 12 Review of Parsons Chemical Site Experience 126
A. 12.1 Unusual Challenges . 126
A. 12.2 Performance Results 127
A. 12.3 Notable Achievements 128
A. 13 Review of SITE Demonstration Results 130
A.14 Acknowledgement 131
VM
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LIST OF TABLES
Table
Table ES-1
Table 2-1
Table 3-1
Table 3-2
Table 4-1
Table 4-2
Table 4-3
Table 4-4
Table 4-5
Table 4-6
Table 4-7
Table 4-8
Table 4-9
Table 4-10
Table 4-1 1
Table 6-1
Table 6-2
Table 6-3
Table 64
Evaluation Criteria for the Geosafe In Situ Vitrification Process
Federal and State Applicable or Relevant and Applicable (ARARs) for the
Geosafe ISV Technology
Summary of Economic Analysis Results for Three Treatment Scenarios
Detailed Summary of Results for Case 2 (3,200 Cubic Yards of Contaminated
Soil)
Results of Analysis of Pre-Treatment Screening Samples Collected from
Cell 8
Performance Data During Demonstration Test Versus ARARs
Geosafe Test Soil Pesticides and Metals Data Summary ,.
Geosafe Test Soil Dioxins/Furans Data Summary
Geosafe Soil TCLP Pesticides and Metals Data Summary
Geosafe Pre-Treatment Test Soil Conductive Cations and Ultimate Analysis
Data
Geosafe Scrubber Water Organics Analysis Summary Data
Geosafe Scrubber Water Metals Analysis Summary Data
Geosafe Scrubber Water Dioxins/Furans Analysis Data
Geosafe Organic Stack Emissions Summary Data
Geosafe Metal Stack Emissions Summary Data
Region V Geosafe Stack Volatile Organic Compound Emissions Summary
Data
Region V Geosafe Stack Semivolatile Organic Compound Emissions Summary
Data
Region V Geosafe Stack Metals Emissions Summary Data
Region V Geosafe Typical CEM Emissions
Page
2
24
34
35
. 68
72
73
74
75
76
81
82
83
86
87
105
Vlll
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LIST OF TABLES (Continued)
Table
Table 6-5 Region V Geosafe HEPA Filter Analysis
Table 6-6 Region V Geosafe Hood Deposit Analysis 108
Table 6-7 Region V Geosafe Neutron Activation Analysis on Treated Soil 109
Table 6-8 Region V Geosafe Melt 1 Excavation Soil Analysis . 110
Table A-l Off-Gas Emission Performance 129
LIST OF FIGURES
Figure
Figure 3-1 Graphical Representation of 12 Cost Categories for Case 2 38
Figure 4-1 Plan View of Treatment Cells 58
Figure 4-2 Cut-Away View of Treatment Cells 59
Figure 4-3 Geosafe In Situ Vitrification Process 60
Figure 4-4 Typical ISV Process Conditions for the Geosafe Technology 62
Figure 4-5 Approximate Location of Actual ISV Melts at the Parsons Site 92
Figure 4-6 Power Input to Cell 8 During the Demonstration Test 95
Figure 4-7 Treatment Time Versus Electrode Depth During the Demonstration
Test (Cell 8) 96
Figure A-l Various Configuration Options for ISV Processing 117
IX
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ACRONYMS, ABBREVIATIONS, AND SYMBOLS
•tg Microgram
ug/kg Microgram s pe r kilogram
ug/L Micrograms per liter
Hg/m3 Micrograms per cubic meter
AQCR Air Quality Control Regions
AQMD Air Quality Management District
ARAR Applicable or relevant and appropriate requirement
ATTIC Alternative Treatment Technology Information Center
BOAT Best Demonstrated Available Technology
BLS Below land surface
CAA Clean Air Act
CEM Continuous emission monitors
CERCLA Comprehensive Environmental Response, Compensation, and Liability Act
CERI Center for Environmental Research Information
CFR Code of Federal RegulFR
CO Carbon monoxide
CO2 Carbon dioxide
CWA Clean Water Act
DDT Dichlorodiphenyltrichlorethane
DRE Destruction removal efficiency
EPAU.S. Environmental Protection Agency
EPA-BREL EP A Risk Reduction Engineering Laboratory
HEPA High efficiency particulate air
HSWA Hazardous and Solid Waste Amendments
ICP Inductively coupled plasma
ISV In Situ Vitrification
ITER Innovative Technology Evaluation Report
kg Kilogram
Ib/hr Pounds per hour
LDR Land Disposal Restriction
MCL Maximum contaminant levels
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ACRONYMS, ABBREVIATIONS, AND SYMBOLS (Continued)
MCLG Maximum contaminant level goals
MDNR Michigan Department of Natural Resources
mg/kg Milligrams per kilogram
mg/L Milligrams per liter
mg/rn3 Milligrams per cubic meter
MW Megawatt
MWh Megawatt hour
NAAQS National Ambient Air Quality Standards
NaOH Sodium Hydroxide
NCP National Oil and Hazardous Substances Pollution Contingency Plan
ND Not detected
ng/kg Nanograms per kilogram
NIST National Institute Standards Technology
NO Nitrogen oxides
NPDES National Pollutant Discharge Elimination System
NTIS National Technical Information Service
OD Outside diameter
ORD EPA Office of Research and Development
OSHA Occupational Safety and Health Act
OSWER Office of Solid Waste and Emergency Response
OVA Organic vapor analyzer
PAH Polynuclear aromatic hydrocarbon
Parsons Parsons Chemical Works, Inc.
PCB Poly chlorinated biphenyl
POTW Publically-owned treatment works
PPE Personal protective equipment
ppmv Parts per million by volume
PVC Polyvinyl chloride
QA Quality Assurance
QAPP Quality Assurance Project Plan
RCRA Resource Conservation and Recovery Act
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ACRONYMS, ABBREVIATIONS, AND SYMBOLS (Continued)
MCLG Maximum contaminant level goals
MDNR Michigan Department of Natural Resources
mg/kg Milligrams per kilogram
mg/L Milligrams per liter
mg/m3 Milligrams per cubic meter
MW Megawatt
MWh Megawatt hour
NAAQS National Ambient Air Quality Standards
NaOH Sodium Hydroxide
NCP National Oil and Hazardous Substances Pollution Contingency Plan
ND Not detected
ng/kg Nanograms per kilogram
NIST National Institute Standards Technology
NO, Nitrogen oxides
NPDES National Pollutant Discharge Elimination System
NTIS National Technical Information Service
OD Outside diameter
ORD EPA Office of Research and Development
OSHA Occupational Safety and Health Act
OSWER Office of Solid Waste and Emergency Response
OVA Organic vapor analyzer
PAH Polynuclear aromatic hydrocarbon
Parsons Parsons Chemical Works, Inc
PCB Polychlorinated biphenyl
POTW Publically-owned treatment works
PPE Personal protective equipment
ppmv Parts per million by volume
PVC Polyvinyl chloride
QA Quality Assurance
QAPP Quality Assurance Project Plan
RCRA Resource Conservation and Recovery Act
XI
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ACRONYMS, ABBREVIATIONS, AND SYMBOLS (Continued)
RREL Risk Reduction Engineering Laboratory
SAIC Science Applications International Corporation
SARA Superfund Amendments and Reauthorization Act
SDWA Safe Drinking Water Act
SITE Superfund Innovative Technology Evaluation
SOX Sulfur oxides
SWDA Solid Waste Disposal Act
TCDD Tetrachlorodibenzo-p-dioxin
TCLP Toxicity Characteristic Leaching Procedure
THC Total Hydrocarbons
tons/yd3 Tons per cubic yard
TSCA Toxic Substances Control Act
VISITT Vendor Information System for Innovative Treatment Technologies
yd3 Cubic yards
xn
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CONVERSIONS
Mass
1 pound (Ib) = 0.4536 kg
1 ton = 2,0001b = 907.18
1 kilogram (kg) = 2,20 Ib
Volume
1 cubic inch (in3) = 5.78E-04 ft3 = 2.14E-05 yd3 - 0,0164 L = 1.64E-05 m3 = 4.33E-03 gal
1 cubic foot (ft3) = 1,728 in3 = 0.0370 yd3 = 28.32 L = 0,0283 m3 = 7.48 gti
1 cubic yard (yd3) = 46,656 in3 = 27 ft3 = 764,55 L = 0.7646 in3 = 201.97 gal
1 cubic meter (m3) = 61,023 in3 = 35,31 ft3 = 1.31 yd3 = 1,000 L = 264,17 gal
1 liter (L) = 61.02 in3 = 0.0353 ft3 = 1.30E-03 yd3 - l.OOE-03 m3 = 0,2642 gal
1 gallon (gal) = 231 in3 - 0.1337 ft3 = 4.95E-03 yd3 = 3,7854 L = 3.79E-03
m3
Length
1 inch (in) - 0,0833 ft - 0.0278 yd = 0.0254 m
1 foot (ft) = 12 in = 0.3333 yd = 0.3048 m
1 yard (yd) = 36 in = 3 ft = 0.9144 m
1 meter (m) = 39,37 in = 3.28 ft = 1.09 yd
Temperature
1 degree Fahrenheit (°F) = 0.5556°C [x°C=0.5556*(y°F-32)]
1 degree Celsius (°C) = 1.8°F [x°F=1.8*(y°C) + 32]
XIII
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CONVERSIONS (Continued)
Pressure
1 pound per square inch (psi) = 27.71 in H2O = 6894.76 Pa
1 inch of water (in H2O) = 0.0361 psi = 248.80 Pa
1 Pascal (Pa) = 1.45E-04 psi = 4.02E-03 in H2O
Viscosity
1 poise = . 1 kg/m-see = 2.09E-03 Ib/ft-sec
1 kg/m-set =10.00 poise = 2.09E-03 Ib/ft-set
1 Ib/ft-sec = 478.70 kg/m-set
Rate
1 Ib/hr = 2.20 kg/hr
1 kg/hr = 0.4536 Ib/hr
xiv
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ACKNOWLEDGEMENTS
This report was developed under the direction of Ms. Teri Richardson, the EPA Technical Project
Manager for this SITE Demonstration at the Risk Reduction Engineering Laboratory (RREL) in
Cincinnati, Ohio. It was prepared by the Process Technology Division of Science Applications
International Corporation (SAIC), San Diego, California under the direction of Mr. Raymond J.
Martrano, the SAIC Work Assignment Manager. Contributors to the report were: Ms. Jamie Sue
Winkelman, engineering and technical writing; Mr. Jonathan E. Rochez, engineering and data evaluation;
and Ms. Ruth D. Alfasso, technical writing. Technical reviews were provided by Mr. Randy Parker and
Ms. Laurel Staley of EPA-RREL and Dr. Victor S. Engleman, Mr. Joseph D. Evans, and Mr. Kyle R.
Cook of SAIC. Special thanks are extended to Mr. Leonard N. Zintak, Jr. of EPA Region V for his
technical review and assistance throughout this project.
xv
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EXECUTIVE SUMMARY
This report summarizes the findings associated with a Demonstration of the Geosafe Corporation
(Geosafe) .In Situ Vitrification (ISV) Process. The Geosafe ISV technology was evaluated under the EPA
Superfund Innovative Technology Evaluation (SITE) Program in conjunction with remediation activities
associated with an EPA Region V removal action. The technology was assessed regarding its ability to
treat pesticides (specifically chlordane, dieldrin, and 4,4'-DDT) and mercury to below Region V
mandated limits. It was evaluated against the nine criteria for decision-making in the Superfund Feasibility
Study process. Table ES-1 presents the results of this evaluation.
The ISV technology uses electric power to heat contaminated soil past its melting point and thus thermally
destroy organic contaminants in the soil. Once the entire treatment volume is molten, power is
discontinued. As the molten mass solidifies, it incorporates inorganic contaminants within a glass and
crystalline vitrified material. Off-gases that are generated during treatment are collected in a containment
hood that is placed over the treatment area. The off-gases are processed by a treatment train which
typically consists of a quencher, a wet scrubber, a demister, a heater, particulate filters, and activated
carbon to process the gas before discharge to the atmosphere. In certain applications, a thermal oxidizer
is used to polish the treated gases before release to the atmosphere. As part of the Region V removal
action, Geosafe performed a total of eight melts which covered nine pre-staged treatment cells at the
Parsons Chemical Works, Inc. (Parsons) site located in Grand Ledge, Michigan. The SITE Program
studied one of these treatment settings (Cell 8) in detail to determine the technology's ability to meet the
Region V removal criteria and to obtain cost and performance data on the technology. This Innovative
Technology Evaluation Report focuses on the findings associated with the SITE Demonstration.
Results presented in this report for the treated soil are based on post-treatment sampling just below the
surface of the melt alone. Complete post-treatment sampling of the solidified melt cannot be safely
performed until at least one year after treatment at which time sampling of the melt core will take place.
Because the technology is already being used in commercial applications, this report has been published
prior to obtaining treated soil samples from the center of the study area. In this manner, the community
may be provided with the information currently available regarding the operability and effectiveness of
the technology. Results of the post-treatment soil samples collected from the core of Cell 8 will be
reported at a later date in a published Addendum.
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Table ES-1. Evalutation Criteria for the Geosafe In Situ Vitrification Process
Overall Protection of
Human Health and the
Environment
Compliance with
ARARS
Long-Term
Effectiveness and
Performance
Short-Term
Effectiveness
Reduction of Toxicity,
Mobility, or Volume
through Treatment
Provides both short- and long-
term protection by destroying
organic contaminants and
immobilizing inorganic
material. Developer also
claims the technology can
treat radioactive compounds.
Remediation can be performed
in situ, thereby reducing the
need for excavation.
Off-gas treatment system
reduces airborne emissions.
System is flexible and can be
adapted for a variety of
contaminant types and site
conditions.
Technology can
simultaneously treat a mixture
of waste types. Technology is
applicable to combustible
materials, but the
concentration of such
materials in the treatment zone
must be carefully controlled
and treatment prudently
planned.
Requires compliance with
RCRA treatment, storage, and
land disposal regulations (for a
hazardous waste). Successfully
treated waste may be delisted
or handled as non-hazardous
waste.
Operation of on-site treatment
unit may require compliance
with location-specific
applicable or relevant
appropriate requirements
(ARARs).
Emission control may be
needed to ensure compliance
with air quality standards
depending upon local ARARs
and test soil components.
Scrubber water will likely
require secondary treatment
before discharging to
publically owned treatment
works (POTW) or surface
bodies. Disposal requires
compliance with Clean Water
Act regulations.
Effectively destroys organic
contamination and immobilizes
inorganic material. Developer
also claims the technology can
treat radioactive compounds.
Reduces the likelihood of
contaminants leaching from
treated soil. ISV glass is
thought to have a stability
similar to volcanic obsidian
which is estimated to remain
physically and chemically
stable for thousands to
millions of years.
Allows potential re-use of
property after treatment.
Treatment of a site using ISV
destroys organic compounds
and immobilizes inorganic
contaminants.
Vitrification of a single
treatment setting may be
completed in approximately
ten days. This treatment time
may vary depending on site-
specific conditions.
Presents potential short-term
chemical exposure risks to
workers operating process
equipment. High voltage and
high temperatures require
appropriate safety precautions.
Some short-term risks
associated with air emissions
are dependent upon test
material composition and off-
gas treatment system design.
Staging, if required, involves
excavation and construction of
treatment areas. A potential
for fugitive emissions and
exposure exists during
excavation and construction.
Significantly reduces toxicity
and mobility of soil
contaminants through
treatment.
Volume reductions of 20 to 50
percent are typical after
treatment.
Some inorganic contaminants,
especially volatile metals, may
be removed by the vitrification
process, and require
subsequent treatment by the
off-gas treatment system.
Some treatment residues may
themselves be treated during
the next vitrification setting.
Residues from the final
setting, including expended or
contaminated processing
equipment, may require
special disposal requirements.
Volume of scrubber water
generated is highly dependent
upon soil moisture content.
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Table ES-1 (Continued)
Itnplcmentability
Cost
Community Acceptance
State Acceptance
Equipment is mobile and can be
brought to a site using conventional
shipping methods. Weight restrictions
on tractors/trailers may vary from state
to state.
Support equipment includes earth-
moving equipment for staging
treatment areas (if required) and
covering treated areas with clean soil.
A crane is required for off-gas
containment hood placement and
movement.
Chemical characterization of
contaminated soil is required for
proper off-gas treatment system
design.
A suitable source of electric power is
required to utilize this technology.
Technology not recommended for sites
which contain organic content greater
than 7 to 10% (by weight), metals
content in excess of 25% (by weight),
and inorganic contaminants greater
than 20% (by volume). Sites with
buried drums may only be treated if
drums are not intact or sealed.
The cost for treatment when the soil is
staged into nine 15-foot deep cells is
approximately 1770/yd1 ($430/ton).
Treatment is most economical when
treating large sites to the maximum
depth.
Electric power is generally the most
significant cost associated with ISV
processing. Other factors (in order of
significance) include labor costs,
startup and fixed costs, equipment
costs, and facilities modifications and
maintenance costs.
Moisture content of the media being
treated directly influences the cost of
treatment since electric energy must be
used to vaporize water before soil
melting occurs.
Sites that require staging and extensive
site preparation will have higher
overall costs.
Technology is generally accepted by
the public because it provides a
permanent solution and because it is
performed in situ.
Potential reuse of land after treatment
provides an attractive alternative to
property owners.
A public nuisance could be created if
odorous emissions from the soil
constituents are not properly controlled
by the off-gas system.
State ARARs may be more stringent
than federal regulations.
State acceptance of the technology
varies depending upon ARARs.
The ISV system (especially the off-gas
treatment portion) is somewhat
modular, such that it may be modified
to meet state-specific criteria.
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CONCLUSIONS BASED ON CRITICAL OBJECTIVES
The studies conducted by the SITE Program suggest the following conclusions regarding the technology's
performance at the Parsons site based on the critical objectives stated for the Demonstration:
The treated soil met the EPA Region V cleanup criteria for the target pesticides and mercury.
Dieldrin and 4,4'-DDT were reduced to levels below their analytical reporting detection limits
(< 16 Mg/kg) m the treated soil. Chlordane was below its detection limit (80 /^g/kg) before
treatment commenced. Mercury, analyzed by standard SW-846 Method 7471 procedures, was
below the specified cleanup level before treatment began, averaging 3,800 ^ig/kg. It was reduced
to an average of less than 33 ng/kg in the treated soil.
Stack gas samples were collected during the Demonstration to characterize process emissions.
There were no target pesticides detected in the stack gas samples. During the Demonstration,
mercury emissions averaged 1.2 x 10" Ib/hr (16ftg/m3). The emissions were below the
regulatory requirement of 5.93 x lO^lb/hr (88 jtg/m3) at all times. Other metal emissions in the
stack gas (particularly arsenic, chromium, and lead) were of regulatory concern during process
operations, but were found to be in compliance with the Michigan state applicable or relevant and
appropriate requirements (ARARs).
Emissions of total hydrocarbons (as propane) and carbon monoxide were'regulated at 100 parts
per million by volume (ppmv) and 150 ppmv, respectively. Throughout the Demonstration, vapor
emissions of these gases (measured downstream from the thermal oxidizer) were well below the
regulatory guidelines. Total hydrocarbon and carbon monoxide emissions both averaged below
10 ppmv.
CONCLUSIONS BASED ON SECONDARY OBJECTIVES
The studies conducted by the SITE Program suggest the following conclusions regarding the technology's
performance at the Parsons site based on the secondary objectives stated for the Demonstration:
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The technology successfully treated the soil in Cell 8, completing the test cell melt in ten days
with only minor operational problems. During this time, approximately 330 yd3 (approximately
600 tons) of contaminated soil were vitrified, according to Geosafe melt summaries.
Approximately 610 MWh of energy was applied to the total soil volume melted (estimated to be
480 yd3) during vitrification of Cell 8; power applied to the actual contaminated soil volume
could not be independently measured because clean fill and surrounding uncontaminated soil are
vitrified as part of each melt. Based on the total soil treated in Cell 8, the energy consumption
was approximately 0.72 MWh/ton, System operation was occasionally interrupted briefly for
routine maintenance such as electrode segment addition and adjustment.
The solid vitrified material collected was subjected to TCLP analysis for the target pesticides and
mercury. Test results indicate that no target pesticides were detected in the post-treatment
leachate. Chlordane was not detected in either the pre- or post-treatment leachate, so no definitive
conclusions can be drawn about the technology's impact on the teachability of this compound
based on this Demonstration. Levels of teachable mercury in both pre- and post-treatment soil
leachates were well below the regulatory limit of 200 ^g/L (40 CFR $261.24). Several other
metals were also found to have passed the TCLP leaching test.
Scrubber water generated during the Demonstration contained volatile organics, partially oxidized
semivolatile organics (phenolics), mercury, and other metals. The scrubber water underwent
secondary treatment before ultimate disposal, and data suggest that secondary treatment of this
waste stream will probably be required in most cases.
Pre-treatment soil dry density averaged 1.5 tons/yd3, while post-treatment soil dry density
averaged 2.1 tons/yd 3. Accordingly, a volume reduction of approximately 30 percent was
observed for the test soil on a dry basis.
The cost for treatment when the soil is staged into nine cells is approximately $1 ,300/yd3
($740/ton) for 5-foot deep cells, $770/yd3 ($430/ton) for 15-foot deep cells (like those at the
Parsons site), and $660/yd3 ($370/ton) for 20-foot deep cells. The costs presented are calculated
based on the number of cubic yards of contaminated soil treated. Because clean fill and
surrounding uncontaminated soil are treated as part of each melt, the amount of material
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treated is higher than the amount of contaminated soil treated. Costs per cubic yard based on total
soil treated would, therefore, be lower than the costs per cubic yard based on contaminated soil
treated presented in this report.
Treatment is most economical when treating large cells to the maximum depth. The primary cost
categories include utilities, labor, and startup and fixed costs.
The following sections of this report contain the detailed information which supports the items
summarized in this Executive Summary. The site studied during this Demonstration was Geosafe's first
large-scale commercial project, and the results presented in this report are based primarily on this
application. Valuable lessons learned at this site have been put into practice in subsequent applications.
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SECTION 1
INTRODUCTION
This section provides background information about the Superfund Innovative Technology Evaluation
program, discusses the purpose Of this Innovative Technology Evaluation Report, and briefly describes
the Geosafe In Situ Vitrification Technology. For additional information about the SITE Program, this
technology, and the Demonstration site, key contacts are listed at the end of this section.
1.1 Background
ISV has been under development since 1980. When it was first researched by Battelle Memorial Institute
(Battelle), ISV was designed to treat radioactive (transuranic) contaminated soil in situ to avoid problems
associated with excavation or transportation of these soils. A successful pilot-scale demonstration of the
technology on radioactive wastes was performed in 1983. It was soon recognized that the technology had
applicability towards other wastes, including hazardous chemical contamination and mixed (chemical and
radioactive) wastes. The Geosafe Corporation (Geosafe) was formed in the spring of 1988 and
subsequently negotiated a sublicense from Battelle for the purpose of establishing ISV in the commercial
marketplace. From this point forward in this report, Geosafe will be considered to be the technology
developer.
In October 1990, EPA began a cleanup of the soil contamination at the former Parsons Chemical Works,
Inc. site (currently occupied by ETM Enterprises) in Grand Ledge, Michigan. The site, designated as a
Super-fund site by the EPA, is located approximately ten miles west of Lansing. Parsons operated at this
location from 1945 until its closure in 1979. Parsons was engaged in the mixing, manufacturing, and
packaging of agricultural chemicals including pesticides, herbicides, solvents, and mercury-based
compounds. Prior to any remedial action, the site contained approximately 3,000 ydj (5,400 tons) of
contaminated soil. The depth of contamination on-site was relatively shallow, five feet or less; therefore,
contaminated soils from three target areas were excavated, consolidated, and staged on-site for treatment.
ISV was the cleanup technology selected for the Parsons site, and Geosafe Corporation of Richland,
Washington was the EPA contractor selected to perform the ISV treatment (I). During remediation of
the Parsons site, a SITE Demonstration of the full-scale Geosafe system was performed. Although
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Geosafe Corporation applied and was accepted into the SITE Program in the late 1980s, they had to wait
approximately two years for the signing of a remediation contract with EPA Region V. Geosafe also
encountered some developmental problems such that the actual SITE Demonstration of this technology
was delayed until March 1994.
1.2 Brief Description of Program and Reports
The SITE Program is a formal program established by the EPA's Office of Solid Waste and Emergency
Response (OSWER) and Office of Research and Development (ORD) in response to the Superfund
Amendments and Reauthorization Act of 1986 (SARA). The SITE Program promotes the development,
demonstration, and use of new or innovative technologies to clean up Superfund sites across the country.
The SITE Program's primary purpose is to maximize the use of alternatives in cleaning hazardous waste
sites by encouraging the development and demonstration of new, innovative treatment and monitoring
technologies. It consists of four major elements:
• the Emerging Technology Program,
• the Demonstration Program,
• the Monitoring and Measurement Technologies Program, and
• the Technology Transfer Program
The Emerging Technology Program focuses on conceptually proven bench-scale technologies that are in
an early stage of development involving pilot or laboratory testing. Successful technologies are
encouraged to advance to the Demonstration Program.
The Demonstration Program develops reliable performance and cost data on innovative technologies so
that potential users may assess the technology's site-specific applicability. Technologies evaluated are
either currently available or close to being available for remediation of Superfund sites. SITE
Demonstrations are conducted on hazardous waste sites under full-scale remediation conditions or under
conditions that closely simulate full-scale remediation conditions, thus assuring the usefulness and
reliability of information collected. Data collected are used to assess: (1) the performance of the
technology, (2) the potential need for pre- and post-treatment processing of wastes, (3) potential operating
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problems, and (4) the approximate costs. The Demonstrations also allow for evaluation of long-term risks
and operating and maintenance costs.
Existing technologies that improve field monitoring and site characterizations are identified in the
Monitoring and Measurement Technologies Program. New technologies that provide faster, more cost-
effective contamination and site assessment data are supported by this program. The Monitoring and
Measurement Technologies Program also formulates the protocols and standard operating procedures for
demonstration methods and equipment.
The Technology Transfer Program disseminates technical information on innovative technologies in the
Emerging Technology Program, the Demonstration Program, and the Monitoring and Measurements
Technologies Program through various activities. These activities increase the awareness and promote the
use of innovative technologies for assessment and remediation at Superfund sites. The goal of technology
transfer activities is to develop interactive communication among individuals requiring up-to-date technical
information,
1.3 The SITE Demonstration Program
Technologies are selected for the SITE Demonstration Program through annual requests for proposals.
ORD staff reviews the proposals to determine which technologies show the most promise for use at
Superfund sites. Technologies chosen must be at the pilot- or full-scale stage, must be innovative, and
must have some advantage over existing technologies. Mobile and in situ technologies are of particular
interest,
Once the EPA has accepted a proposal, cooperative agreements between the EPA and the developer
establish responsibilities for conducting the Demonstration and evaluating the technology. The developer
is responsible for demonstrating the technology at the selected site and is responsible for any costs for
transport, operations, and removal of the equipment. The EPA is responsible for project planning,
sampling and analysis, quality assurance and quality control, preparing reports, disseminating
information, and transporting and disposing of treated waste materials.
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The results of this evaluation of the Geosafe In Situ Vitrification Technology are published in two basic
documents: the SITE Technology Capsule and this Innovative Technology Evaluation Report (ITER). The
SITE Technology Capsule provides relevant information on the technology, emphasizing key features of
the results of the SITE field Demonstration while the ITER provides an in-depth evaluation of the overall
performance and applicability of the technology.
1.4 Purpose of the Innovative Technology Evaluation Report
This ITER provides information on the Geosafe In Situ Vitrification Technology for treatment of
contaminated soils and includes a comprehensive description of this Demonstration and its results. The
ITER is intended for use by EPA remedial project managers, EPA on-scene coordinators, contractors,
and other decision-makers carrying out specific remedial actions. The ITER is designed to aid decision-
makers in further evaluating specific technologies for further consideration as applicable options in a
particular cleanup operation. This report represents a critical step in the development and
commercialization of a treatment technology.
To encourage the general use of demonstrated technologies, the EPA provides information regarding the
applicability of each technology to specific sites and wastes. The ITER includes information on cost and
performance, particularly as evaluated during the Demonstration. It also discusses advantages,
disadvantages, and limitations of the technology
Each SITE Demonstration evaluates the performance of a technology in treating a specific waste. The
waste characteristics of other sites may differ from the characteristics of the treated waste. Therefore, a
successful field demonstration of a technology at one site does not necessarily ensure that it will be
applicable at other sites. Data from the field demonstration may require extrapolation for estimating the
operating ranges in which the technology will perform satisfactorily. Only limited conclusions can be
drawn from a single field demonstration.
1.5 Brief Technology Description
In situ vitrification uses electrical power to heat and melt soil and other earthen materials (e.g., dewatered
sludge, mine tailings, buried waste, and sediments) contaminated with organic, inorganic, and radioactive
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compounds. Due to the intense heat of the process, organic contaminants within the treatment volume
undergo pyrolysis (thermal decomposition in the absence of oxygen). The pyrolysis products then migrate
to the surface of the treatment zone where they are oxidized under a collection hood. Large amounts of
ambient air are used to cool the collection hood and to sweep the off-gases to the treatment system. An
air pollution control system treats the off-gases generated prior to discharge. The remaining molten
material cools to form a monolithic glass-like product that incorporates the thermally stable inorganic
compounds present within the treatment zone. The glass material is claimed to have very low leaching
characteristics (2,3,4)
The Geosafe ISV technology uses a square array of four graphite electrodes that allows a melt width of
approximately 20 to 40 feet and a potential treatment depth of up to 20 feet. Multiple settings may be
used for remediation of a larger contaminated area Electric power is supplied to the electrodes through
flexible conductors. Initially, the electrodes are inserted one to two feet below the soil surface, and a
conductive starter path is laid between them. An electric potential is applied to the electrodes to establish
an electrical current in the starter path. Upon melting (at temperatures in the vicinity of 2,000 to
2,500°F), the soil becomes electrically conductive. As the soil surrounding the electrodes becomes
molten, the electrodes can be lowered until the desired treatment depth is attained.
In a single setting, the process can remediate contaminated soil at an estimated rate of four to six tons
per hour until a maximum mass of 800 to 1,200 tons has been treated. After treatment, the vitrified mass
is typically left in place, although it can be removed if necessary after cooling. Subsidence, resulting from
the elimination of void volume and removal of humus and organic contaminants, is remedied by
backfilling over the melt with clean material.
A more in-depth description of the process may be found in Section 4.4 of this report, "Detailed Process
Description." Appendix A, "Vendor's Claims," provides some additional information.
1.6 Key Contacts
Additional information about the Geosafe In Situ Vitrification Technology and the SITE Program can be
obtained from the following sources
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The Geosafe In Situ Vitrification Technology
Mr. James E. Hansen
Geosafe Corporation
Director of Business Development and Communications
2950 George Washington Way
Richland, Washington 99352
Phone: 509/375-07 10
Fax: 509/375-7721
The SITE Program
Ms. Teri L. Richardson
EPA SITE Technical Project Manager
U . S Environmental Protection Agency
Risk Reduction Engineering Laboratory
26 West Martin Luther King Drive
Cincinnati, OH 45268
Phone: 5 13/569-7949
Fax: 5 13/569-7620
Information on the SITE Program is available through the following on-line information clearinghouses
• The Alternative Treatment Technology Information Center (ATTIC) System (operator:
703/908-2 137) is a comprehensive, automated information retrieval system that integrates
data on hazardous waste treatment technologies into a centralized, searchable source. This
database provides summarized information on innovative treatment technologies.
• The Vendor Information System for Innovative Treatment Technologies (VTSITT)
(hotline: 800/245-4505) database currently contains information on approximately 23 1
technologies offered by 141 developers.
• The OSWER CLU-IN electronic bulletin board contains information on the status of
SITE technology Demonstrations. The system operator can be reached at 301/589-8368.
Technical reports may be obtained by contacting the Center for Environmental Research Information
(CERI), 26 Martin Luther King Drive in Cincinnati, OH, 45268 at 513/569-7562.
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SECTION 2
TECHNOLOGY APPLICATIONS ANALYSIS
This section of the report addresses the general applicability of the Geosafe ISV technology to
contaminated soil sites. The analysis is based primarily on this SITE Demonstration, and conclusions are
based exclusively on these data since only limited information is available on full-scale applications of
the technology. This SITE Demonstration was conducted on approximately 400 cubic yards of soil, of
which an estimated 330 cubic yards were contaminated with low levels of pesticides, dioxins/furans,
mercury, and other metals,
2.1 Key Features
The Geosafe ISV system is an in situ technology that allows on-site treatment of contaminated wastes
without excavation and with only limited site preparation. The technology is unique in that it can
effectively treat a wide variety of contamination including hazardous chemical (both organic and
inorganic), radioactive, and mixed (chemical and radioactive) wastes. ISV can treat sites that would
otherwise require two or more technologies to handle the same range of contaminants. Although the
application of this technology to radioactive and mixed wastes was not studied as part of the
Demonstration, full-scale testing for this type of treatment has been successfully conducted.
In situ treatment is advantageous, especially when volatile organic compounds are present or when large
quantities of contaminated soils are present since soil handling activities may be minimized. If the
contamination is shallow or scattered, the soil may be excavated, consolidated, and staged for treatment.
Operation utilizes electric energy to melt the soil, driving off and decomposing organic contaminants and
immobilizing thermally stable compounds in a matrix claimed to be relatively non-leachable. The residual
product has very stable geological characteristics, similar to volcanic obsidian. Contaminants that are
diffkult to treat using other techniques can be bound into this glass and crystalline vitrified material. The
vitrified mass is typically left in place, and thus the need for disposal of the treated material can be
eliminated. The developer claims that the vitrified material is non-hazardous and can be delisted. Delisting
procedures are very site-specific and could vary significantly from state to state.
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Treatment by ISV effectively reduces the mobility of the contaminants and the toxicity and volume of the
contaminated media. The mobility of contaminants is diminished when teachable constituents are
incorporated into a non-leachable mass. The toxicity of the soil is reduced by the destruction and removal
of organic contaminants and volatile metal compounds. The potential for lateral migration is restricted
through the use of refractory walls when using staged treatment. Compounds that are vaporized but not
destroyed by the vitrification process are passed through an off-gas treatment system. The removal of
materials that can be vaporized and void space between soil particles as a result of the vitrification process
produces a 20 to 50 percent volume reduction according to the developer.
2.2 Operability of the Technology
The Geosafe ISV technology operates using electrical energy to heat and melt soil, destroying organic
contaminants by means of pyrolysis and oxidation, thermally decomposing some inorganic contaminants,
and immobilizing thermally stable contaminants. The most important operational parameter for this
technology is the electrical input to the melt. A maximum of 1.75 MW of power is supplied through each
of the two phases of the electrical system (A and B), such that maximum total power to the electrodes
during treatment is about 3.5 MW. Initially, the current applied to the soil is low (100 to 200 amps per
phase) and the voltage is quite high (up to 4,000 volts per phase). However, as the melt progresses, the
voltage is decreased and the current is increased as the molten soil becomes more conductive. The voltage
applied to each of the two phases during full power operation averages only 600 volts while the current
for each phase averages 2,900 amps. Treatment of a typical 15-foot deep single cell requires up to 1,200
MWh of energy; however, the cell treated during the Demonstration required only 610 MWh
(approximately 0.72 MWh/ton), much less than other cells at the Parsons site. According to the vendor,
normal energy consumption is approximately 1 MWh/ton. The high rates of consumption dictate that
electricity is a primary factor when considering costs and availability of resources.
Although ISV can treat saturated soils, the presence of large amounts of water or a high water table
hinders operation of the ISV technology. When water is present, electrical energy is initially used to
vaporize this water instead of melting the contaminated soil, thus prolonging treatment time and
increasing costs. The resulting water vapors must be handled by the off-gas treatment system and further
increases project costs. An overabundance of water does not preclude treatment with ISV, but may make
it prohibitively expensive. As with most thermal technologies, the cost of treatment increases with the
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amount of water that has to be removed; therefore, it is economically wise to keep the treatment zone
as dry as possible prior to treatment
Weather is another factor which affects the operability of the Geosafe system. Rain or snow at the
treatment site increases the amount of water in the soil and can lead to the difficulties discussed above.
High humidity increases the amount of liquid handled by the off-gas treatment system. Moving the hood
becomes more difficult in windy conditions, but may still be accomplished safely. Temperature is not a
critical factor. Cold ambient temperatures may increase the amount of initial heating required but once
the soil is in a molten state, the surrounding area stays warm due to the thermal insulating properties of
the soil. Extreme temperatures (hot or cold) make working conditions less favorable for personnel and
equipment. The ISV process was successfully operated at the Parsons site during a typical Michigan
winter season.
When contaminated soil volumes are shallow or scattered, the soil can be excavated, consolidated, and
staged in a treatment area. This was illustrated at the Parsons site where the contaminated soil was
excavated from three selected areas and placed in nine pre-constructed treatment cells. The cell walls
were constructed of concrete; a layer of cobble was placed outside of the concrete, and a sheet of
plywood was used to separate the treatment cells from the surrounding uncontaminated soil. The bottom
of the cells were constructed of cobble covered with a plastic liner. Some aspects of the cell structure
used at the Parsons site proved unsuitable for effective implementation of the technology. This issue is
further discussed in Section 4 of this report, "Treatment Effectiveness."
For the SITE Demonstration, one of the nine treatment cells was vitrified. This cell contained
approximately 400 cubic yards of soil, 330 of which was estimated to be contaminated. During the
removal action supervised by EPA Region V at the Parson Chemical site, all nine cells (approximately
3,000 cubic yards of contaminated soil) were treated. Because of the way the melts grew during
treatment, remediation of the nine cells was accomplished in eight melts rather than nine
2.3 Applicable Wastes
The ISV technology can treat a wide range of waste matrices contaminated with a variety or mixture of
contaminant types. The technology can be used on soils, sludges, sediments, mine tailings, and similar
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assembly and shakedown) is approximately three weeks. If a more rapid setup is required, more than one
shift of workers may be utilized per day.
2.5 Materials Handling Requirements
The amount of materials handling required depends mainly on whether the contaminated soil is staged
or treated in situ. Treatment of soils that are not moved, and that do not require pre-treatment, does not
necessitate much additional equipment. Earth-moving equipment (such as a backhoe and/or a dump truck)
is required to backfill the subsidence of treated areas.
If soils are to be staged, or if mixing of wastes is required, soil excavation equipment is needed. The
actual equipment used depends on the amount and characteristics of the contaminated soil. A backhoe is
commonly used to move soil on a site, with or without an accompanying dump truck. A conveyor belt
or similar device can be used to transport soil from a temporary staging area to treatment cells. Special
equipment or modifications to existing equipment may be recommended for excavation of soils containing
volatile contaminants in order to reduce volatilization and exposure of personnel or the community.
Sampling of soils before and after treatment may also require the use of materials handling equipment.
Soil in situ can be sampled using a drill rig, a backhoe, a shovel, or another device depending on the
characteristics of the soil and the depths to be sampled. After treatment, samples of the solidified matrix
may need to be collected using a specially-equipped drill rig or jackhammer
During both setup and treatment, a crane and other support equipment are required. The crane is used
to erect the hood during assembly, to move the hood over each melt before treatment, and to add
electrodes during treatment. Other equipment, such as a forklift, may be needed to move drums and
miscellaneous supplies on the site.
2.6 Site Support Requirements
The main site requirement for use of ISV is the availability of electricity. For the unit used during the
Demonstration, 4 MW are required at a voltage of either 12,500 or 13,800 volts. These voltages are
standard grid voltages available in the United States. Power can be supplied through trailer-mounted
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diesel generators in situations where building a connection to the power grid would be unfeasible. The
costs of using diesel-generated power are generally higher than that for grid electricity.
If a thermal oxidizer is part of the treatment train, then a source of natural gas or fuel oil is required. A
natural gas connection to the local utility was made at the Parsons site to supply natural gas during the
Demonstration. It may be possible to obtain an electric secondary combustion device that provides the
necessary off-gas treatment. Although this would eliminate the need for fuel, the use of natural gas or
fuel oil would probably be more economical if it is available.
Other utilities required for the use of ISV include water for cleaning, for use in the scrubber, and for
personnel needs. Only small amounts of potable water are required. Phone service to the site is required
for general communications and to summon emergency assistance. A connection to the sewer may also
be needed to discharge scrubber water or diverted groundwater. Portable toilets may be used as toilet
facilities.
Access to the site must be provided over roads suitable for travel by heavy equipment. The trailers can
travel over regular roads, but may not be allowed on low capacity bridges or especially steep grades.
Personnel must also be able to reach the site without difficulty, since three shifts of personnel are utilized
during treatment. Auxiliary facilities are needed for storage of supplies and tools, and for office and rest
areas. Mobile trailers and storage containers can be brought on-site for these purposes. Because the ISV
process is operated continuously, the top of the hood is equipped with floodlights which illuminate the
work areas after dark. Additional site lighting may be required in other areas for nighttime operation.
When the ISV equipment is utilized in an inhabited area, site security measures are required both to
protect the public from accidental exposures and to prevent accidental or intentional damage to the
equipment. A fence surrounded the Parsons site to provide additional security.
2.7 Ranges of Suitable Site Characteristics
Because ISV can operate on soils in situ, applicable waste characteristics (discussed in Section 2.3) and
suitable site characteristics overlap somewhat. The site characteristics described in this section provide
additional information about items which require consideration before treatment of a site.
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Apart from appropriate soil types discussed previously, the required geological conditions include stable
formations which can support the treatment equipment. The treatment surface must be level to allow
placement of the ISV equipment and facilitate effective sealing of the soil/hood interface to prevent escape
of fugitive emissions. Groundwater present in the treatment area makes treatment more time consuming
and costly (as described earlier). Diverting groundwater around the treatment area may make remediation
more efficient.
The treatment area cannot contain utility lines or other underground facilities, since these would be
destroyed by the treatment and may pose a safety hazard (e.g., buried gas lines). If the treatment soil or
adjacent areas contain highly permeable natural or artificial conduits in the less permeable matrix, special
precautions may need to be taken to prevent the melt from extending outside the planned treatment zone
and to prevent fugitive emissions of toxic or odorous gases. These precautions may include removal of
the more permeable material, mixing it with the other soil, or the construction of restraining walls, such
as the refractory concrete walls used during the Demonstration.
The use of ISV requires space for placement of the process equipment, auxiliary equipment and buildings,
and waste staging (when required). The process trailers occupy an area of approximately 10 feet by 120
feet. The off-gas hood is 60 feet in diameter, while the area treated in a single melt measures
approximately 27 feet by 27 feet; therefore, sufficient space must be available around the perimeter of
the treatment area to place and seal the hood. An extra buffer of space between the contaminated soil and
any areas that are not a part of the site is also required so that unexpected melt growth does not have an
adverse off-site impact.
The Geosafe equipment can operate in nearly any climate. Since soil is a good insulating material, very
cold climates do not inhibit treatment other than perhaps slowing its initiation. Equipment can be
climatized to prevent damage due to exposure to hot, cold, or wet conditions.
The ISV process can be used in fairly close proximity to inhabited areas, so long as appropriate measures
are taken to prevent off-site emissions, odors, or noise. The presence of lights and noise may preclude
use in some residential areas, since the system must be operated continuously for effective application.
Heavy equipment must be transported to and from the site on occasion, however, once the equipment is
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operating, there is little additional traffic generated to the site. The small crew size limits the number of
vehicles on-site.
2.8 Limitations of the Technology
The size of a melt which can be generated is limited to approximately 40 feet by 40 feet and a maximum
depth of about 20 feet (800 to 1,200 tons) with the current ISV technology. For treatment of deeper
contamination, Geosafe has proposed using a multi-layered staged approach in which the upper portion
of contaminated soil may be excavated while the deeper portion of contaminated soil is treated in situ.
The excavated soil would then be replaced and treated in situ atop the previously vitrified material. This
would, however, increase the complexity of treatment and the cost per cubic yard. Demonstrations of this
approach have not yet been performed.
Because the ISV process operates in situ, it may not be appropriate for sites where contaminated soil
exists directly adjacent to buildings, other structures, or the property line. Staging or the use of insulating
refractory walls can be used in some cases, but will probably increase the costs.
Costs per cubic yard are minimized when a sufficient amount of waste is treated at the site to distribute
the costs of mobilization. Small amounts of contaminated soil may be more efficiently treated with other
methods or at an off-site facility. ISV may not be the least expensive method to treat a waste with only
one type of contamination (e.g., volatile organics or metals), but it may be favored when in situ treatment
is desired. ISV also offers unique opportunities and potential cost savings when treating sites with
multiple types of contamination-sites that would normally require the use of two or more technologies
or a treatment train to accomplish treatment goals. In some instances, ISV may be the most cost-effective
treatment alternative
After treatment with ISV, the soil is molten and very hot. The molten mass may take more than a year
to fully cool. Although the surface of each completed melt is covered with a thick layer of clean fill, the
heat may prevent re-use of the site until complete cooling has occurred. The monolith of solidified
material is dense and hard, which minimizes leaching and breakdown. If required, the cooled vitrified
mass may be removed from the site. Intentional rapid cooling of the melt may induce shrink-cracking of
the surface, a desirable effect if the solidified block is to be broken apart and removed. Activities such
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as drilling through the treated material to install a building foundation or monitoring wells require state-
of-the-art technology, but can be accomplished using appropriate techniques.
Limits on the amounts of contaminants which can be present in media suitable for treatment by ISV are
determined by the heat removal capacity of the off-gas treatment system. The treatment soil is limited to
a maximum of seven to ten percent organics by weight for effective remediation using the current off-gas
treatment equipment. Additional or modified off-gas treatment components could allow treatment of a
waste with a higher organic content.
Previous experience has indicated that safe, effective treatment becomes more difficult when pockets of
flammable liquid or vapor in sealed containers exist beneath the soil surface. Combustible materials may
also present treatment difficulties since the sudden release of gases may exceed the heat load and
volumetric capacity of the off-gas treatment system, resulting in a loss of hood vacuum and a potential
for fugitive emission releases. The sudden gas release may also cause bubbling and spattering of molten
material which can damage the hood and may carry molten material away from the melt, creating a
potential safety hazard. The most effective means of treatment exists when contaminants are evenly
distributed throughout the soil and so will not cause sudden overload of gas-processing and other
equipment. Buried drums also present potential problems if they are sealed and contain significant
amounts of liquid
Metals in their reduced chemical state may sink to the bottom of the melt, concentrate there, and cause
the electrodes to short-circuit. This metal-induced shorting may be encountered in soils that have high
amounts of iron (or other similar metals). The developer claims that most metals are not reduced in an
ISV melt and that short-circuiting of the electrodes can be prevented through use of the feeding
mechanism which can retract the electrodes temporarily when a large metal object is encountered or when
shorting is experienced
2.9 ARARS for the Geosafe ISV Technology
This subsection discusses specific federal environmental regulations pertinent to the operation of the
Geosafe ISV technology including the transport, treatment, storage, and disposal of wastes and treatment
residuals. Federal and state applicable or relevant and appropriate regulations (ARARs) are presented in
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Table 2-1 These regulations are reviewed with respect to the Demonstration results. State and local
regulatory requirements, which may be more stringent, must also be addressed by remedial managers.
ARARs include the following: (1) the Comprehensive Environmental Response, Compensation, and
Liability Act; (2) the Resource Conservation and Recovery Act; (3) the Clean Air Act; (4) the Safe
Drinking Water Act; (5) the Toxic Substances Control Act; and (6) the Occupational Safety and Health
Administration regulations. These six general ARARs are discussed below.
2.9.1 Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA)
The CERCLA of 1980 as amended by the Superfund Amendments and Reauthorization Act (SARA) of
1986 provides for federal funding to respond to releases or potential releases of any hazardous substance
into the environment, as well as to releases of pollutants or contaminants that may present an imminent
or significant danger to public health and welfare or to the environment.
As part of the requirements of CERCLA, the EPA has prepared the National Oil and Hazardous
Substances Pollution Contingency Plan (NCP) for hazardous substance response. The NCP is codified
in Title 40 Code of Federal Regulations (CFR) Part 300, and delineates the methods and criteria used to
determine the appropriate extent of removal and cleanup for hazardous waste contamination.
SARA states a strong statutory preference for innovative technologies that provide long-term protection
and directs EPA to do the following:
use remedial alternatives that permanently and significantly reduce the volume, toxicity
or mobility of hazardous substances, pollutants, or contaminants;
select remedial actions that protect human health and the environment, are cost-effective,
and involve permanent solutions and alternative treatment or resource recovery
technologies to the maximum extent possible; and
avoid off-site transport and disposal of untreated hazardous substances or contaminated
materials when practicable treatment technologies exist [Section 121(b)].
Geosafe's ISV technology meets each of these requirements. Volume, toxicity, and mobility of
contaminants in the waste matrix are all reduced as a result of treatment. Organic compounds are
removed and destroyed; the vitrified product permanently immobilizes inorganic constituents. The need
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Table 2-1. Federal and State Applicable or Relavant and Applicable Regulations (ARARs) for the Geosafe ISV Technology
PROCESS ARAR
ACTIVITY
DESCRIPTION OF
REGULATION
GENERAL
APPLICABILITY
SPECIFIC
APPLICABILITY
TO ISV
Waste
characterization of
untreated waste
RCRA: 40 CFR Part
261 (or state
equivalent)
Standards that apply to
identification and
characterization of wastes
Chemical and physical
analyses must be performed
to determine if waste is a
hazardous waste .
Chemical and physical
properties of waste
determine its
suitability for
treatment by ISV.
Soil excavation
CAA: 40 CFR Part
50 (or state
equivalent)
Regulation governs toxic
pollutants, visible emissions
and particulates
If excavation is performed,
emission of volatile
compounds or dusts may
occur.
Only applies to staged
treatment. Handling
practices should
minimize volatilization
and dust production.
Waste processing
RCRA: 40 CFR Part
264 (or state
equivalent)
CAA: 40 CFR Part
50 (or state
equivalent)
Standards that apply to
treatment of wastes in a
treatment facility
When hazardous wastes are
treated, there are
requirements for operations,
recordkeeping, and
contingency planning.
Regulation governs toxic Stack gases may contain
pollutants, visible emissions volatile organic compounds
and particulates or other regulated gases.
Applicable or
appropriate for ISV
operations.
During ISV treatment,
stack gases must not
exceed limits set for
the air district of
operation. Standards
for monitoring and
recordkeeping apply.
-------
Table 2-1. (Continued)
ACTIVITY ARAR
DESCRIPTION OF
REGULATION
GENERAL
APPLICABILITY
SPECIFIC
APPLICABILITY TO
ISV
Storage of auxiliary
wastes
to
Ut
RCRA: 40 CFR Part
264 Subpart J (or state
equivalent)
Regulation governs
standards for tanks at
treatment facilities
RCRA: 40 CFR Part
264 Subpart I (or state
equivalent)
Regulation covers storage of
waste materials generated
If storing non-RCRA
wastes, RCRA requirements
may still be relevant and
appropriate.
Applicable for RCRA
wastes; relevant and
appropriate for non-RCRA
wastes
Storage tanks for liquid
wastes (e.g., scrubber
water) must be
placarded properly,
have secondary
containment and be
inspected daily.
Containers of process
stream residuals (e.g.,
filters) need to be
labeled as hazardous
waste. The storage area
needs to be in good
condition, weekly
inspections are
required, and storage
should not exceed 90
days unless a storage
permit is acquired.
Determination of
cleanup standards
SARA: Section
SDWA: 40 CFR Part
141
Standards that apply to
surface and groundwater
sources that may be used as
drinking water
Remedial actions of surface
and groundwater are
required to meet maximum
contaminant level goals
(MCLGs) or maximum
contaminant levels (MCLs)
established under SDWA -
No specific-
applicability to ISV
unless groundwater
treatment is specified as
part of the cleanup
criteria.
-------
Table 2- (Continued)
PROCESS ACTIVITY ARAR
Waste disposal
RCRA: 40 CFR Part
262
CWA: 40 CFR Parts
403 and/or 122 and
125
RCRA: 40 CFR Part
268
DESCRIPTION OF
REGULATION
Standards that pertain to
generators of hazardous
waste
Standards for discharge of
wastewater to a publically
owned treatment works
(POTW) or to a navigable
waterway
Standards regarding land
disposal of hazardous wastes
GENERAL
APPLICABILITY
Generators must dispose of
wastes at facilities that are
permitted to handle the
waste. Generators must
obtain an EPA ID number
prior to waste disposal.
Discharge of wastewaters to
a POTW must meet pre-
treatment standards;
discharges to a navigable
waterway must be permitted
under national pollution
discharge elimination system
(NPDES).
Hazardous wastes must meet
specific treatment standards
prior to land disposal, or
must be treated using
specific technologies.
SPECIFIC
APPLICABILITY TO
ISV
Waste generated may
include filters or other
solid wastes not
consumed in a melt.
Wastewater disposal
most applicable to
scrubber water
discharge.
May be applicable for
off-site disposal of
auxilliary wastes. May
also be applicable to
the solidified vitrified
soil, if materials were
staged for treatment.
ISV may be a best
demonstrated available
technology (BOAT) for
some wastes
-------
for off-site transportation and disposal of solid waste is eliminated by in situ treatment. Scrubber water
generated during the SITE Demonstration required secondary treatment before ultimate disposal at a
permitted facility, and off-gas emissions were treated prior to release to the atmosphere. The developer
claims that secondary wastes, including scrubber water, may be recycled to subsequent melts. In some
cases, according to the developer, this may accomplished by filtering and discharging the water and
treating the filter in a subsequent melt
In general, two types of responses are possible under CERCLA: removal and remedial action. Between
1986 and 1992, in situ vitrification was selected as the source control remedy at four Superfund sites in
one removal action (the Parsons site) and three remedial actions (1). Superfund removal actions are
conducted in response to an immediate threat caused by a release of hazardous substances. Removal
action decisions are documented in an action memorandum. Many removals involve small quantities of
waste or immediate threats requiring quick action to alleviate the hazard. Remedial actions are governed
by the SARA amendments to CERCLA. As stated above, these amendments promote remedies that
permanently reduce the volume, toxicity and mobility of hazardous substances, pollutants, or
contaminants.
On-site removal and remedial actions must comply with federal and often more stringent state ARARs.
AFURs are determined on a site-by-site basis and may be waived under six conditions: (I) the action is
an interim measure, and the ARAR will be met at completion; (2) compliance with the ARAR would pose
a greater risk to health and the environment than noncompliance; (3) it is technically impracticable to
meet the ARAR; (4) the standard of performance of an ARAR can be met by an equivalent method; (5)
a state AR4R has not been consistently applied elsewhere; and (6) ARAR compliance would not provide
a balance between the protection achieved at a particular site and demands on the Superfund for other
sites. These waiver options apply only to Superfund actions taken on-site, and justification for the waiver
must be clearly demonstrated.
2.9.2 Resource Conservation and Recovery Act (RCRA)
RCRA, an amendment to the Solid Waste Disposal Act (SWDA), is the primary federal legislation
governing hazardous waste activities and was passed in 1976 to address the problem of how to safely
dispose of municipal and industrial solid waste. Subtitle C of RCRA contains requirements for generation,
27
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transport, treatment, storage, and disposal of hazardous waste, most of which are also applicable to
CERCLA activities. The Hazardous and Solid Waste Amendments (HSWA) of 1984 greatly expanded
the scope and requirements of RCRA.
RCRA regulations define hazardous wastes and regulate their transport, treatment, storage, and disposal.
These regulations are only applicable to the Geosafe ISV Technology if RCRA-defined hazardous wastes
are present. If soils are determined to be hazardous according to RCRA (either because of a characteristic
or a listing carried by the waste), all RCRA requirements regarding the management and disposal of
hazardous waste must be addressed by the remedial managers. Criteria for identifying characteristic
hazardous wastes are included in 40 CFR Part 261 Subpart C. Listed wastes from specific and nonspecific
industrial sources, off-specification products, spill cleanups, and other industrial sources are itemized in
40 CFR Part 261 Subpart D. For this Demonstration, the technology was subject to RCRA regulations
because the Parsons site is a Superfimd site contaminated with RCRA-listed wastes including
dioxins/furans, chlordane, dieldrin, 4,4'-DDT, mercury, and arsenic. RCRA regulations do not apply to
sites where RCRA-defined hazardous wastes are not present.
Unless they are specifically delisted through delisting procedures, hazardous wastes listed in 40 CFR Part
261 Subpart D remain listed wastes regardless of the treatment they may undergo and regardless of the
final contamination levels in the resulting effluent streams and residues. This implies that, even after
remediation, treated wastes are still classified as hazardous because the pre-treatment material was a listed
waste.
For generation of any hazardous waste, the site responsible party must obtain an EPA identification
number. Other applicable RCRA requirements may include a Uniform Hazardous Waste Manifest (if the
waste is transported), restrictions on placing the waste in land disposal units, time limits on accumulating
waste, and permits for storing the waste.
Requirements for corrective action at RCRA-regulated facilities are provided in 40 CFR Part 264, Subpart
F (promulgated) and Subpart S (partially promulgated). These subparts also generally apply to
remediation at Superfund sites. Subparts F and S include requirements for initiating and conducting
RCRA corrective action, remediating groundwater, and ensuring that corrective actions comply with other
environmental regulations. Subpart S also details conditions under which particular RCRA requirements
28
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may be waived for temporary treatment units operating at corrective action sites and provides information
regarding requirements for modifying permits to adequately describe the subject treatment unit.
2.9.3 Clean Air Act (CAA)
The CAA establishes national primary and secondary ambient air quality standards for sulfur oxides,
particulate matter, carbon monoxide, ozone, nitrogen dioxide, and lead. It also limits the emission of 189
listed hazardous pollutants such as arsenic, asbestos, benzene, and vinyl chloride. States are responsible
for enforcing the CAA. To assist in this, Air Quality Control Regions (AQCR) were established.
Allowable emissions are determined by the AQCR, or its sub-unit, the Air Quality Management District
(AQMD). These emission limits are determined based on whether or not the region is currently within
attainment for National Ambient Air Quality Standards (NAAQS).
The CAA requires that treatment, storage, and disposal facilities comply with primary and secondary
ambient air quality standards. Fugitive emissions from the ISV technology may come from (1) the
untreated soil during sampling or staging (volatile organic compounds or dusts), (2) the area around the
hood during treatment, (3) the treated air exhaust stack during treatment, or from (4) the still-molten
treated soil. Under the CAA, the ISV treatment must not exceed the current standards for any pollutant
that may be present in the waste soil or formed during treatment. Because of the thermal nature of the
ISV process, the potential for generating regulated compounds exists. The off-gas treatment system must
be designed to meet the current emission standards. State air quality standards may require additional
measures to prevent emissions
2.9.4 Clean Water Act (CWA)
The objective of the CWA is to restore and maintain the chemical, physical, and biological integrity of
the nation's waters. To achieve this objective, effluent limitations of toxic pollutants from point sources
were established. Publically owned treatment works (POTWs) can accept waste water with toxic
pollutants; however the facility discharging the waste water must meet pre-treatment standards and may
need a discharge permit. A facility desiring to discharge water to a navigable waterway must apply for
a permit under the National Pollutant Discharge Elimination System (NPDES). When an NPDES permit
is issued, it includes waste discharge requirements for volumes and contaminant concentrations
29
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The only waste water from the ISV process which may need to be managed is the scrubber water that
is used to cool the off-gas and remove particulates and acid gases. The volume of waste water generated
includes the original charge of liquid to the scrubber and water condensed from the gas stream. The
amount of waste water to be managed depends on the water content of the soil undergoing treatment and
the moisture content of the gas stream. Because of the presence of mercury in the soil, the waste water
generated from the scrubber during the ISV Demonstration was not treated and discharged on-site, but
was transported to an off-site facility for disposal. The CWA was therefore not an ARAR for the
Demonstration site, but it could be in other applications where discharge to a POTW is performed.
Safe Drinking Water Act (SDWA)
The SDWA of 1974, as most recently amended by the Safe Drinking Water Amendments of 1986,
requires the EPA to establish regulations to protect human health from contaminants in drinking water.
The legislation authorized national drinking water standards and a joint federal-state system for ensuring
compliance with these standards.
The National Primary Drinking Water Standards are found in 40 CFR Parts 141 through 149. These
drinking water standards are expressed as maximum contaminant levels (MCLs) for some constituents,
and maximum contaminant level goals (MCLGs) for others. Under CERCLA (Section 121(d)(2)(A)(ii)),
remedial actions are required to meet the standards of the MCLGs when relevant. For the ISV
Demonstration, treatment of contaminated groundwater was not a part of the removal actions. Leaching
tests such as the toxicity characteristic leaching procedure (TCLP) or state-specific tests are often used
to determine whether water may be impacted by contaminated soils. ISV immobilizes or encapsulates
contaminants in a glass and crystalline structure. The TCLP is frequently used after treatment by ISV to
determine the final teachability of contaminants within a vitrified mass.
Toxic Substances Control Act (TSCA)
The TSCA of 1976 grants the EPA authority to prohibit or control the manufacturing, importing,
processing, use, and disposal of any chemical substance that presents an unreasonable risk of injury to
human health or the environment. These regulations may be found in 40 CFR Part 761; Section 6(e) deals
specifically with PCBs. Materials with less than 50 ppm PCB are classified as non-PCB; those containing
30
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between 50 and 500 ppm are classified as PCB-contaminated; and those with 500 ppm PCB or greater
are classified as PCB. PCB-contaminated materials may be disposed of in TSCA-permitted landfills or
destroyed by incineration at a TSCA-approved incinerator; PCBs must be incinerated. Sites where spills
of PCB-contaminated material or PCBs have occurred after May 4, 1987 must be addressed under the
PCB Spill Cleanup Policy in 40 CFR Part 761, Subpart G. The policy establishes cleanup protocols for
addressing such releases based upon the volume and concentration of the spilled material.
TSCA may be relevant or appropriate for use of ISV, since the technology is capable of treating wastes
containing or contaminated with PCBs. TSCA was not an ARAR at the ISV Demonstration at the Parsons
site because no PCBs were detected in the treated waste
2.9.7 Occupational Safety and Health Administration (OSHA) Requirements
CERCLA remedial actions and RCRA corrective actions must be performed in accordance with the
OSHA requirements detailed in 20 CFR Parts 1900 through 1926, especially $1910.120 which provides
for the health and safety of workers at hazardous waste sites. On-site construction activities at Superfund
or RCRA corrective action sites must be performed in accordance with Part 1926 of OSHA, which
describes safety and health regulations for construction sites. State OSHA requirements, which may be
significantly stricter than federal standards, must also be met.
All technicians operating the Geosafe ISV system and all workers performing on-site construction are
required to have completed an OSHA training course and must be familiar with all OSHA requirements
relevant to hazardous waste sites. Workers on hazardous waste sites must also be enrolled in a medical
monitoring program. The elements of any acceptable program must include: (1) a health history, (2) an
initial exam before hazardous waste work starts to establish fitness for duty and a medical baseline, (3)
periodic (usually annual) examinations to determine whether changes due to exposure may have occurred
and to ensure continued fitness for the job, (4) appropriate medical examinations after a suspected or
known overexposure, and (5) an examination at termination.
For most sites, minimum PPE for workers will include gloves, hard hats, safety glasses, and steel-toe
boots. Depending on contaminant types and concentrations, additional PPE, including respirators or
supplied air may be required. Additional requirements for protective clothing are dictated by the use of
31
-------
high power electricity on the site, and these requirements should be used to specify the types of boots,
gloves and hard hats which are used during operation.
The vapor hood of the Geosafe ISV system may be considered a confined space. If workers are required
to enter beneath the hood while it is on the ground, the actions must comply with the recently
promulgated OSHA requirements for confined spaces (29 CFR §1910.146), including requirements for
stand-by personnel, monitoring, placarding, and protective equipment. If excavation of the waste is
required on the site, trenches and excavations may be considered additional confined spaces (based on
type and depth) and the same requirements would have to be met. Other construction- or plant-related
OSHA standards may also apply during ISV operations, including shoring of trenches, and lock-out/tag-
out procedures on powered equipment.
Noise levels are not expected to be high, with the possible exception of noise caused by soil handling
activities. During these activities, noise levels should be monitored to ensure that workers are not exposed
to noise levels above a time-weighted average of 85 decibels over an eight-hour day. If noise levels
increase above this limit, workers will be required to wear ear protection. The levels of noise anticipated
are not expected to adversely affect the community, depending on its proximity to the treatment site.
2.9.8 State Requirements
In many cases, state requirements supersede the corresponding Federal program, such as OSHA or
RCRA, when the state program is Federally approved and the requirements are more strict. The state of
Michigan had other regulatory requirements which are not covered under the major Federal programs
including special requirements for operating on a floodplain.
32
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SECTION 3
ECONOMIC ANALYSIS
The primary purpose of this economic analysis is to provide a cost estimate (not including profit) for full-
scale application and use of the Geosafe ISV system. The costs associated with this technology are
identified in 12 cost categories defined by EPA that reflect typical cleanup activities encountered on
Superfund sites. Each of these categories is defined and discussed, thus forming the basis for this cost
analysis,
Costs estimated in this economic analysis are largely based on actual conditions experienced at the
Parsons site. The vendor claims to have made substantial improvements relative to these numbers and
should be contacted for current cost estimates. Appendix A of this report presents the vendor's claims
in detail.
3.1 Conclusions and Results of the Economic Analysis
This economic analysis estimates the cost of using the Geosafe ISV system for three cases-Case 1, Case
2, and Case 3 corresponding treatment of approximately 970, 3,200, and 4,400 cubic yards (1,700,
5,700, and 7,900 tons) of contaminated soil in nine staged treatment cells. This represents three different
cell depths (5, 15, and 20 feet) for the same size site. The costs for Case 1, Case 2, and Case 3 are
estimated to be $1,300, $770, and $660 per cubic yard ($740, $430, and $370 per ton), respectively.
Costs presented in this report are order-of-magnitude estimates as defined by the American Association
of Cost Engineers, with an expected accuracy within +50% and -30% ; however, because this is a new
technology, the range may actually be wider. Table 3-1 presents a summary of the 12 cost categories for
each case. Table 3-2 presents a detailed summary for the cost associated with Case 2 (3,200 cubic yards)
which most closely parallels conditions observed at the Demonstration site. Figure 3-1 shows a graphical
representation of the contributions of each of the categories to the total cost for Case 2.
The economic analysis for the case most similar to the conditions experienced at the Parsons site (Case
2) shows that the primary cost categories include utilities, labor, and startup and fixed costs, each
contributing roughly 20% to the total cost (utilities slightly higher). Equipment costs and facilities and
maintenance costs are each responsible for roughly 10% of the total treatment cost. The other two cases
33
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Table 3-1. Summary of Economic Analysis Results for Three Treatment Scenarios
Case 1
Cost Category
1. Site and Facility 'Preparation
2. Permitting and Regulatory Requirements
3. Equipment
4. Startup and Fixed
5. Labor
6. Consumables and Supplies
7, Utilities
8. Effluent Treatment and Disposal
9. Residuals .and Waste Shipping and Handling
10. Analytical Services
11. Facility Modifications and Maintenance
12. Site Demobilization
TOTAL COST PER CUBIC YARD
TOTAL COST PER TON*
970
$/yd3
51
27
190
260
250
80
180
0
34
52
170
37
1,300
740
yd3
%
4
2
15
20
19
6
14
0
3
4
13
3
100
Case
3,200
$/yd3
18
9
98
130
150
61
170
0
26
19
86
13
770
430
2
yd3
%
2
1
13
17
19
8
22
0
3
2
11
2
100
Case
4,400
$/yd3
13
7
83
no
130
52
160
0
23
14
69
9
660
370
3
yd3
%
2
1
13
17
20
8
24
0
3
2
10
1
100
* Assuming wet soil density of 1.8 tons/yd3 based on SITE Demonstration results.
Note: All costs arc based on contaminated soil treated.
Total costs are rounded to two significant figures and based on the sum of the individual costs before
rounding. For this reason, the sum of the numbers presented in this table may not match the total
precisely.
34
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Table 3-2. Detailed Summary of Results for Case 2 (3,200 Cubic Yards of Contaminated Soil)
Case 2
3,200 yd3
$/yd3*
1 SITE AND FACILITY PREPARATION
Site Design and Layout
Survey and Site Investigations
Legal Searches
Access Rights and Roads
Preparations for Support Facilities
Auxiliary Buildings
Utility Connections
Transportation of Waste Feed
Technology-Specific Requirements
Transportation
Assembly
TOTAL
2. PERMITTING AND REGULATORY REQUIREMENTS
Permits
Environmental Monitoring Requirements
Development of Monitoring Protocols
Stand-Down
TOTAL
3. EQUIPMENT
Major Equipment (to estimate other costs)
Annualized Equipment (prorated)
Equipment Rental
100-Ton Crane
25Ton Crane
Forklift
Front-End Loader
Dump Truck
Storage Tank
Thermal Oxidizer
Trailers
Toilets
TOTAL
0.00
0.00
0.00
4.81
12.95
17.76
9.50
9.50
78.68
4.05
0.85
2.10
1.24
0.43
1.76
8.25
0.71
0.24
98.31
0
0
0
15,400
41,400
30,400
30,400
4,000,000
251,800
13,ooo
2,700
6,700
4,ooo
1,400
5,600
26,400
2,300
800
314,700
(Continued)
-------
Table 3-2. (Continued)
Case 2
3,200 yd3
$/yd3* $
4.
5.
6.
7.
STARTUP ANTI FIXED
Startup
Working Capital
Insurance and Taxes
Initiation of Monitoring Programs
Contingency
TOTAL
LABOR
Total Melt Labor
Total Move Labor
Per Diem
Rental Cars
Airfare
TOTAL
CONSUMABLES AND SUPPLIES
Consumables
Electrodes
Graphite and Glass Frit
Insulating Blanket
"Refractory Concrete
NaOH
HEPA Filters
Scrub Solution Bag Filters
** Carbon Filters
Office Supplies
Health and Safety Supplies
TOTAL
UTILITIES
Natural Gas
Water
Electricity
TOTAL
8.62
14.61
53.72
53.72
130.67
75.95
25.93
23.88
9.95
10.61
146.33
22.79
0.15
4.23
7.83
1.28
11.04
0.57
11.97
0.24
1.13
61.23
1.02
0.02
166.05
167.10
27,600
46,800
171900
171900
418^00
243,100
83jOOO
76,400
31,800
34,000
468300
72900
500
13^00
25,100
4,100
35300
1,800
38300
800
3,600
195,900
3,300
100
531,400
534^00
(Continued)
36
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Table 3-2. (Continued)
Case 2
3,200 yd3
$/yd3*
8. EFFLUENT TREATMENT AND DISPOSAL
On-Site Facility
Off-Site Facility
TOTAL
9. RESIDUALS AND WASTE SHIPPING AND HANDLING
Preparation
Waste Disposal
Scrubber/Decontamination Water
Solid Waste
TOTAL
10. ANALYTICAL SERVICES
Soil Samples
Gas Samples
Scrubber Samples
Glass Samples
Operational Monitoring
TOTAL
11. FACILITY MODIFICATIONS AND MAINTENANCE
Design Adjustments
Facility Modifications
Scheduled Maintenance (materials)
Equipment Replacement (hood panels)
TOTAL
12. SITE DEMOBILIZATION
Disassembly
Site Cleanup and Restoration
Permanent Storage
TOTAL
TOTAL
0.00
1.77
19.04
4.86
25.67
4.27
4.27
4.27
4.27
1.42
18.52
35.81
50.56
86.38
12.95
0.00
0.00
12.95
774.40
5,700
60SCO
15,500
82400
13,700
13,700
13,700
13,700
4,500
59,300
114,600
161,800
276,400
41,400
0
0
41,400
2,478,000
*Costs presented are per ydj of contaminated soil treated.
Costs presented in the body of the report have been rounded to two significant figures. Additional
significant figures have purposely been retained in this detailed table.
**May not be required at every site.
37
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Coat Breakdown by Category for Can 2 (3,200 Yd' Contaminated Soil)
2 PERMITTING & REGULATORS
REQUIREMEUTS
1%
1 SITE 4 FACILITY
PREPARATION
2%
12 SITE DEMOBILIZATION
2%
11. FACttJTY MOOVCATIONS A
HE!**
11%
10 ANALYTICAL SERVICES
2*
9 RESIDUALS A WASTE
SHIPPING A HANDLING
3%
3-2. Co*» (of Efflu*n(
•>• z«Q for
w«i 'Swvfoni net, slxwm ix- th
Figure 3-1. Graphical Representation of 12 Cost Categories for Case 2
38
-------
show similar cost distributions. Treatment is most economical when treating large soil volumes to the
maximum depth, particularly since down-time between melts is minimal compared to actual treatment
time. A high ratio of down-time to melt time results in increased costs per cubic yard for some categories
(e.g., labor) because total treatment time is not linearly related to total treatment volume. On a per cubic
yard basis, the contribution of utilities (as a percentage of total cost) increases markedly with increased
treatment volume. As expected, the contributions of labor costs and consumables and supplies costs also
increase with increased treatment volume. The contributions of all other cost categories as a percentage
of total cost decrease with increased treatment volume.
3.2 Issues and Assumptions
This economic analysis was developed based primarily on information collected during the treatment of
Cell 8 at the Parsons site. Costs have been extrapolated where necessary, and when treatment of Cell 8
did not yield representative data, information was obtained from Geosafe so that a fair estimate of typical
treatment could be generated.
This cost analysis provides estimates for the three treatment scenarios described below. In each case,
staged treatment is assumed to take place in nine treatment cells measuring 27 feet by 27 feet. Preliminary
analysis indicated little variation in cost per cubic yard when treatment depth remained constant and the
number of cells was varied. The contributions of categories such as site and facility preparation costs,
startup and fixed costs, and, site demobilization costs (on a per cubic yard basis) decrease, as expected,
when the number of cells is increased because their contributions can be amortized over a longer
treatment period. However, the impact of varying the number of treatment cells appeared to have little
effect on the overall cost per cubic yard of contaminated soil treated. Therefore, the three cases present
data for treatment in which the number of cells remains constant and the treatment depth (and thus total
volume) is varied. The depth of treatment is assumed to exceed the depth of contaminated soil by one
foot. Although included in this cost estimate, the layer of clean fill on top of the contaminated soil may
be less than specified or not required at all in some cases. If clean fill is not required, the overall
treatment volume (and therefore treatment cost) may be reduced. The three cases presented in this report
are as follows:
39
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• Case 1: Cell depth of 5 feet with a 0.5foot layer of clean fill on top of the contaminated
soil such that the depth of contaminated soil is 4.5 feet and the total treatment depth is
6 feet.
• Case 2: Cell depth of 15 feet with a 2-foot layer of clean fill on top of the contaminated
soil such that the depth of contaminated soil is 13 feet and the total treatment depth is 16
feet.
• Case 3: Cell depth of 20 feet with a 2-foot layer of clean fill on top of the contaminated
soil such that the depth of contaminated soil is 18 feet and the total treatment depth is 21
feet.
Case 1 was selected to present information representative of what may be considered to be a minimum
treatment depth for economically feasible application of ISV. Case 2 was selected to present economic
data representative of conditions observed during the Demonstration and ISV treatment at the Parsons
site. It should be noted that treatment of the nine cells (approximately 3,000 cubic yards) at Parsons was
actually accomplished in eight melts. This economic analysis assumes that, in each case, the process
completes nine melts in nine settings. Case 3 was selected to provide information representative of the
current maximum treatment depth for ISV.
The costs for each case of this economic analysis are presented per cubic yard of contaminated (not total}
soil treated. When using ISV, the total volume of soil treated exceeds the contaminated volume of soil
treated. Three factors must, therefore, be taken into account to determine the total volume of soil treated
corresponding to the contaminated volume of soil treated. These factors are: 1) the layer of clean fill
(one-half to two feet); 2) the actual treatment depth (one foot beyond the contaminated soil depth); and
3) an overmelt correction of 15% (by volume) to account for overmelting beyond the perimeter of the
treatment zone and remelting to facilitate overlapping treatment. The amount of soil treated in excess of
the amount of contaminated soil is dependent on the actual treatment configuration.
The focus of this cost estimate is on Case 2 which represents the Demonstration at the Parsons site.
During the Demonstration, it was estimated by Geosafe that approximately 330 cubic yards of
contaminated soil were treated in one treatment cell. In this cost analysis, a cell treatment volume of
approximately 350 cubic yards of contaminated soil is used in the calculations for Case 2. When taking
into consideration the three factors mentioned above, the volume of total soil treated is approximately 500
cubic yards per cell. Thus, Case 2 is based on treatment of approximately 3,200 cubic yards of
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contaminated soil and approximately 4,500 cubic yards of total soil. Because the total amount of soil
treated exceeds the amount of contaminated soil treated, costs per cubic yard of total soil treated would
necessarily be lower
Overall costs to the site owner would probably be less when staged cells are not used since excavation
and cell construction costs may be eliminated, however, undocumented underground features (e.g., buried
tanks, drums, telephone or electrical cables, etc.) may potentially increase treatment costs for in situ
treatment
Important assumptions regarding operating conditions and task responsibilities that could significantly
impact the cost estimate results are presented below:
0 The cost estimates presented in this analysis are representative of charges typically
assessed to the client by the vendor and do not include profit. Costs such as preliminary
site preparation, permits and regulatory requirements, initiation of monitoring programs,
and site cleanup and restoration are considered to be the responsible party's (or site
owner's) obligation and are not included in the estimate presented. These costs tend to
be very site-specific, and calculations are left to the reader. Whenever possible,
applicable information is provided on these topics so that the reader may independently
perform calculations to acquire economic data desired.
• It is assumed that the, contaminated soil will be staged into treatment cells by an
independent contractor prior to Geosafe's arrival on-site.
• The density of the untreated soil (on a wet basis) is assumed to be 1.8 tons per cubic
yard.
• Treatment is assumed take place 24 hours per day, 7 days per week, 52 weeks per year.
An on-line efficiency factor of 80% has been incorporated to account for down-time due
to scheduled and unscheduled maintenance and other unforeseen delays. Down-time to
move the hood is accounted for separately.
• Capital costs for equipment are limited to the cost of the ISV system (off-gas hood,
electrical transformers, power cables, and electrode feeders) the basic gas treatment
system (quench tank, scrubber, demister, particulate filter system, activated carbon
system, and glycol cooling system), and the backup gas treatment system. Percentages
of the total equipment cost are used to estimate other costs.
• During treatment, three shifts of workers are assumed to work eight hours per day, seven
days per week for three weeks. At the end of three weeks, one shift of workers is rotated
out, and a new set replaces the former. The rotation of workers is set up so that each
worker works for three weeks straight, and then rests for one week.
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• Operations for a typical shift require two workers: one shift engineer and one operator.
Additionally, one site manager and one project control specialist are present on-site
during the day shift. Off-site office support corresponding to 50% of one person's full-
time responsibilities is also required.
• The costs presented (in dollars per cubic yard) are calculated based on the number of
cubic yards of contaminated soil treated. Because clean fill and surrounding
uncontaminated soil are treated as part of each melt, the total amount of material treated
may be approximately 35 to 55 percent higher. Costs per cubic yard based on total soil
treated would, therefore, be lower than those presented in this estimate.
Many actual or potential costs that exist, including treatability studies, were not included as part of this
estimate. They were omitted either because the costs were assumed to be the obligation of the responsible
party or because site-specific engineering designs that are beyond the scope of the SITE project would
be required. The costs of treatability studies could range from $40,000 to $80,000 depending on the
application (2,3,4). Analytical costs can be a major factor in treatability studies, depending on the
number and type of analyses required
3.3 Basis of the Economic Analysis
This cost analysis was prepared by breaking down the overall cost into 12 categories defined by EPA.
The categories, some of which do not have costs associated with them for this particular technology, are:
• Site and Facility Preparation Costs
• Permitting and Regulatory Requirements Costs
• Equipment Costs
• Start-up and Fixed Costs
• Labor Costs
• Consumables and Supplies Costs
• Utilities Costs
• Effluent Treatment and Disposal Costs
• Residuals and Waste Shipping and Handling Costs
• Analytical Services Costs
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I
• Facility Maintenance and Modifications Costs
• Site Demobilization Costs
The 12 cost factors examined as they apply to the Geosafe ISV system, along with the assumptions
employed, are described in detail below.
3.3.1 Site and Facility Preparation Costs
For these cost calculations, "site" refers to the location of the contaminated waste. Site design and layout,
survey and site investigations, legal searches, and access rights and roads are assumed to be the
responsibility of the site owner. Support facilities and auxiliary buildings are not required for this
technology because the system is self-contained with mobile trailers used for auxiliary buildings. Utility
connections may or may not be required; the specific characteristics of the site may cause this cost to
fluctuate greatly, and therefore, costs are not included in this estimate. It should be noted that utility
connections, while normally available from standard United States electrical grids, may be of particular
importance for this technology because of the high power demands of the system. Because ISV is an in
situ technology, the location of the contaminated waste is assumed to be the same as the location of the
treatment facility; thus, there are no costs for transportation of the contaminated waste.
For the purposes of this cost estimate, it is assumed that the contaminated soil will be excavated and
staged into treatment cells by an independent contractor prior to Geosafe's arrival on-site. Although the
costs of this activity are not included in this estimate because they are site-specific, typical excavation and
placement costs may be assumed here. If staging is not required, a reduction in site preparation costs may
be experienced; however, if the contaminated soil is not excavated and consolidated, unidentified buried
items may be encountered and must be handled appropriately
Transportation charges are only assessed for travel to a treatment site since it is anticipated that, once a
job is completed, the equipment will be transported directly to the next site without returning to Geosafe's
home office. Trucking charges include drivers and are based on an 80,000-pound legal load. The ISV
process equipment is contained on or in three mobile trailers: a process trailer, a support trailer, and an
electrical trailer. The three process trailers are typically moved by two tractors (two of the trailers are
towed together). An overweight permit is necessary for transport of the electrical trailer. This is the only
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trailer that requires a permit. Three additional trailers are required for transportation of the hood,
electrode feeders, backup gas treatment system, and other associated piping and equipment. Thus,
transportation of the ISV system requires a total of five tractors and six trailers. It is assumed that
overweight permits can be obtained for under $50 per state and that permits will be required for an
average of four states per trip. Using a 1,000-mile basis as a typical transportation distance and an
estimated cost per mile of $3.00, the total transportation cost is approximately $15,000, Depending on
the number of states that are traversed and the amount of state fees that are assessed for permits and road
usage, this cost may vary. The transportation cost from Geosafe Corporation in Richland, Washington
to the Parsons site in Grand Ledge, Michigan was higher than this estimate (approximately $34,000 total)
due in part to the great distance travelled and to the peculiar weight limitations of Michigan roads. The
$15,000 figure has been used for this cost estimate to present what may be anticipated as typical
transportation costs.
Assembly of the Geosafe ISV system requires a full crew of eight Geosafe employees plus three local
workers working eight hours per day for ten days. Office support from the home office is also required
for four hours per day (one person). Two cranes are required: a 25-ton crane for one week (seven days)
and a 100-ton crane for half of one day (four hours). Assembly costs are limited to labor charges
(including rental cars and per diem) and crane rental fees. Information on labor rates may be found under
"Labor Costs. "
3.3.2 Permitting and Regulatory Requirements Costs
The cost of permitting and regulatory requirements is generally the obligation of the responsible party
(or site owner), not that of the vendor. These costs may include actual permit costs, system monitoring
requirements, and the development of monitoring and analytical protocols. Modifications to the system
may also be required to maintain compliance with the regulations. Permitting and regulatory costs can
vary greatly because they are very site- and waste-specific. No permitting costs are included in this
analysis, however, depending on the treatment site, this may be a significant factor since permitting
activities can be very expensive and time consuming. The costs of environmental monitoring (including
the development of monitoring protocols) are determined by the requirements imposed by the local
governing agency. Because they are site- and waste-specific, these costs are not included here.
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Stand-down costs (costs incurred while the system is not in use) for this technology, which are included
in the cost estimate, are in the vicinity of $5,000 per day. It is therefore advisable that, to the maximum
extent possible, permitting and regulatory requirements are carefully researched and appropriate permits
obtained prior to the initiation of treatment. Even so, it is likely that some stand-down time will occur
while samples are being analyzed to determine compliance. It is assumed that one day of stand-down time
will be incurred for each sampling episode and that one sampling episode will be required for every three
cells treated.
3.3.3 Equipment Costs
Equipment costs include major pieces of equipment, purchased support equipment, and rental equipment.
Support equipment refers to pieces of purchased equipment and/or subcontracted items that will only be
used for one project.
The major pieces of equipment are the off-gas hood, the electrode feeders, electrical cables, the off-gas
treatment system (including quencher, scrubber, mist eliminator, particulate filter system, and activated
charcoal system), the back-up off-gas treatment system, the glycol cooling system, and the electrical
system. The electrodes themselves are considered consumables. No support equipment is purchased or
sub-contracted for operation of this system. Rental equipment includes a 25-ton crane, a 100-ton crane,
a forklift, a front-end loader, a dump truck, a storage tank, one mobile office trailers, one mobile
decontamination trailer, and two portable toilets. In some cases, rental of modular additions to the gas
treatment system may also be necessary. At the Parsons site, a rented thermal oxidizer was required to
fully treat the off-gases. To remain consistent throughout the analysis, it is assumed that a thermal
oxidizer is required in each case.
The capital cost of the complete system is assumed to be $4,000,000. Although the client does not
purchase the system, the cost of remediation must account for the annualized cost of the equipment. The
capital equipment costs are presented as annualized equipment costs, prorated for the amount of time the
equipment is used for the project. The annualized equipment cost is calculated using a ten-year equipment
life and 10% annual interest rate. The annualized equipment cost is based upon the writeoff of the total
initial capital equipment cost and scrap value (5,6), assumed to be 10% of the original equipment cost.
The following equation is used:
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Capital recovery = (V -V) — —
(1 + /)"
where V = the cost of the original equipment ($4,000,000),
V, = the salvage value of the equipment ($400,000),
n = the equipment life (10 years), and
i = the annual interest rate (10%) (4,5).
The capital cost of equipment is the same for each case. The annualized cost of the equipment is prorated
over the assembly time, startup time, total treatment time, and disassembly time. In each case, assembly
and disassembly time remain constant at ten days each; startup time remains constant at seven days. Total
treatment time for nine settings, including soil melt time and hood move time, is estimated to be 73 days
when the depth of the cell is 5 feet, 130 days when the depth of the cell is 15 feet (as during the
Demonstration), and 150 days when the depth of the cell is 20 feet.
A 25-ton crane is rented at a rate of $95 per hour to provide assistance with hood movement and
electrode addition. The 25-ton crane is required for an estimated two hours per cell when the cell depth
is 5 feet, for four hours per cell when the cell depth is 15 feet, and for an estimated six hours per cell
when the cell depth is 20 feet. A 100-ton crane is rented at a rate of $200 per hour for eight hours (one
day) each time the hood is moved. Crane rental charges for assembly and disassembly are included under
"Site and Facilities Preparation Costs" and "Site Demobilization Costs," not "Equipment Costs." A
forklift is rented at a rate of $1,300 per month for assembly time, startup time, total treatment time, and
disassembly time. A front-end loader ($440 per day) and a dump truck ($150 per day) are each rented
for one day to backfill the melt subsidence each time the hood is moved, nine days total. A 20,000-gallon
Baker * storage tank is rented at a rate of $38 per day for the total treatment time; the costs for delivery
and pickup of the tank are each $350. One mobile office trailer and one mobile decontamination trailer
are rented at a rate of $150 per month for assembly time, startup time, total treatment time, and
disassembly time; the costs for delivery and pickup are each $180. Two portable toilets are rented at a
rate of $60 per month for assembly time, startup time, total treatment time, and disassembly time; the
costs for pickup and delivery are $40 each. A thermal oxidizer is rented at a rate of $5,000 per month
for assembly time, startup time, total treatment time, and disassembly time; the costs for pickup and
delivery are each $300.
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3.3.4 Start-up and Fixed Costs
Start-up and fixed costs are considered to include such things as startup operations, security, working
capital, insurance and taxes, and contingency. For the most part, these costs are independent of the length
of treatment time. Working capital varies slightly with treatment depth and the time required to treat each
cell. Insurance and taxes and contingency costs are prorated over the assembly time, startup time, total
treatment time, and disassembly time
Startup costs are limited to labor charges (including rental cars and per diem) for a full crew (eight
persons) working eight hours per day for one week (seven days). Operations will not take place 24 hours
per day during startup since melting is not initiated until after the startup and shakedown processes are
complete. Information on labor rates may be found under "Labor Costs."
To protect both the site and the public, site security is required whenever Geosafe personnel are not on-
site. Since 24-hour operations are assumed to take place only during treatment (actual melting), security
is required overnight during all other phases of the project (i.e., assembly, startup, hood moves, and
disassembly). At these times, one security guard is required for eight hours per day. The labor rate for
a security guard is assumed to be $10 per hour.
Working capital is the amount of money currently invested in consumables and supplies. The working
capital cost of consumables and supplies is based on maintaining a one-month inventory of these items.
(See "Consumables and Supplies Costs" for the specific amounts required for the operation of the system.
Note that the cost of consumables and supplies varies slightly with treatment depth and the time required
to treat each cell.) The total cost of consumables and supplies divided by the total number of treatment
months yields the monthly cost of consumables and supplies. This dorresponds to the amount of money
required to maintain a one-month inventory of consumables and supplies.
Insurance is usually 1% and taxes are usually 2 to 4% of the total purchased equipment capital costs
(approximately) on an annual basis. The cost of insurance for a hazardous waste process can be several
times more. Together, annual insurance and taxes are assumed to be 10% of the purchased equipment
capital costs (7) for the purposes of this estimate. The cost is prorated over the assembly time, startup
time, treatment time and disassembly time.
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The cost of the initiation of monitoring programs is very site- and waste-specific. Requirements for the
initiation of monitoring programs are generally determined by the state agency governing hazardous waste
operations. Applicable costs would be assessed prior to treatment and would not likely extend into the
treatment phase of remediation. The cost of environmental monitoring is discussed under "Permitting and
Regulatory Requirements Costs" above.
An annualized contingency cost of 10% of the total purchased equipment capital costs is allowed for any
unforeseen or unpredictable cost conditions, such as strikes, storms, floods, and price variations (5,6).
This cost is prorated over the assembly time, startup time, treatment time and disassembly time.
3.3.5 Labor Costs
Labor costs include overhead and administrative costs and are limited to hourly labor rates, per diem,
daily transportation, and travel. Labor charges are assessed only during the total treatment time since
labor costs for other activities (such as assembly, startup and disassembly) are included elsewhere. Labor
charges during treatment are broken down into two categories: soil melts and hood moves.
During a melt, operations take place in three shifts. The day shift (8 A.M. to 4 P.M.) requires a site
manager, an engineer, a project control specialist, and an operator. The swing shift (4 P.M. to 12 A.M. )
and the graveyard shift (12A.M. to 8 A.M.) each require an engineer and an operator. During hood
moves, the full crew (a site manager, three engineers, a project control specialist, and three operators)
is present. Operations are eight hours a day during hood moves. To coordinate on-site operations with
the home office, it assumed that office support requirements total 50% of one person's full-time
responsibilities.
Hourly labor rates are as follows: site manager, $60; engineer, $40; project control specialist, $30;
operator, $30; local worker, $20; office support, $40. .Per diem (daily meals and accommodations) is
estimated at $75 per day per person. Daily transportation includes a rental car and fuel at $50 per day.
One rental car is provided for the site manager; a second rental car is provided for the process control
specialist. One additional rental car is provided for each shift of workers for a total of five rental cars.
Round trip travel costs are assumed to be $1,000 per person, and it is assumed that, based on a rotating
schedule of three weeks on and one week off, each person will travel home and back to the site once each
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month during treatment. Regular trips home are not scheduled during assembly, startup, and disassembly
The site manager, project control specialist, engineers, and operators require per diem, daily
transportation to the site, and round trip travel to the site. Local workers are only employed during
assembly and disassembly and do not require per diem, daily transportation to the site, or round trip
travel to the site. Office support personnel provide assistance from the home office and are not required
to be present on-site; hourly labor is the only applicable charge for office support.
3.3.6 Consumables and Supplies Costs
The Geosafe ISV process utilizes a square array of four electrodes to melt soil. The electrodes used are
solid graphite and supplied in 12-inch outside diameter (OD) six-foot threaded sections. The cost of the
graphite electrodes is approximately $1 per pound, and each six-foot section weighs approximately 500
pounds, resulting in an electrode cost of $500 per section. The total cost for electrodes is based on whole
(six-foot) sections used during each melt. That is, even if the melt is only sixteen feet deep, electrode
usage is assumed to be eighteen feet (three six-foot electrode sections). Geosafe shears the electrodes near
the surface at the conclusion of a melt for reuse, but the location of the cut with respect to the threads
determines the usefulness of the sheared electrodes.
A conductive mixture of graphite and glass frit is laid in a pattern on the untreated soil surface between
the electrodes to provide a starter path for the electrical current Approximately 75 pounds of frit
available for about $1 per pound, are required for every melt
A synthetic material is used to insulate the untreated soil surface and to protect the hood from undesirable
contact with molten soil during the early stages of treatment. This insulating "blanket" is available by the
roll at a cost of $1.70 per square foot. Approximately 900 square feet are required to cover the soil
surface beneath the hood for each cell
Refractory concrete is a material that can be used to prevent convective melt erosion of the soil wall and
limit melt width. This material has recently been employed to restrict melt growth to the desired areas
Prefabricated sheets can be used to form the walls of the cells constructed for staged treatment
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Refractory concrete may be considered a staging cost rather than a consumable, but for this cost estimate,
it is categorized as a consumable item. Refractory concrete is available at a cost of $0.25 per pound. The
use of refractory concrete is not required when the cell depth is 5 feet because melt width is not a
problem at such shallow depths. When the cell depth is 15 feet (based on experience at Parsons),
approximately 11,000 pounds of refractory concrete are required per cell, and an estimated 15,000
pounds when the cell depth is 20 feet. The need for and the use of refractory concrete may vary from
site to site and even from cell to cell. Using a conservative approach, the quantities in this estimate
assume that refractory concrete is used in every cell treated over the entire cell depth. Geosafe proposes
that refractory concrete may only be required at the "beltline" (widest point) of the melt and not over the
full depth.
Sodium hydroxide (NaOH) is utilized as a caustic in the scrubbers. For this process, a 50% NaOH
solution is used. It is available for $150 per 55-gallon drum. The amount of NaOH required depends on
the volume and characteristics of soil treated. It is also influenced by the performance of the scrubber and
the ambient weather conditions. It is estimated that one drum per cell is required when the cell depth is
5 feet, three drums per cell when the cell depth is 15 feet, and four drums per cell when the cell depth
is 20 feet.
High efficiency particulate air (HEPA) filters are used in the off-gas treatment system to collect fine
particulate matter. These filters are consumed at a rate dependent on the soil characteristics, the treatment
time, and the performance of the off-gas treatment system. In some cases, it may not be necessary to use
HEPA filters to meet state particulate limits. Demonstration results indicate that approximately 25 HEPA
filters were used during treatment of each 15-foot cell. It is assumed that an estimated 10 HEPA filters
are required for each 5-foot cell, and 35 filters are required for each 20-foot cell. Each HEPA filter costs
approximately $160. The high cost and high rate of consumption of HEPA filters motivated Geosafe to
develop techniques whereby the filters could be reused and recycled, reducing the overall cost of HEPA
filters.
Bag filters used by the scrubber portion of the off-gas treatment system are available at $2.50 per filter.
The number of filters used during treatment of each cell is dependent on the amount volume of scrubber
water generated. This volume is highly variable. Approximately 80 filters were required per cell during
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treatment at the Parsons site (15foot cells). It is estimated that 25 filters are required for treatment of
5-foot cells and 100 filters are required for treatment of 20-foot cells.
Carbon filters, employed to process the off-gas before release to the atmosphere, are used for normal
operations in the absence of a thermal oxidizer. In some instances, such as at the Parsons site, carbon
filters may be used in addition to a thermal oxidizer. Carbon filters were consumed at a rate of four per
15-foot cell at Parsons. The number of carbon filters is variable and dependent on the volume and nature
of off-gas generated as well as the performance of the off-gas system. It is assumed that an estimated two
filters are required per 5-foot cell and five filters are required per 20-foot cell
General office supplies are required to maintain efficient operation at the site from the time of assembly
and startup through treatment and disassembly. The monthly cost for office supplies is approximately
$150.
Health and safety supplies are required for all phases of the project including assembly, startup,
treatment, and disassembly. The monthly cost of health and safety supplies varies slightly with the phase
of treatment but averages approximately $700.
337 Utilities Costs
Electricity is a primary cost for this technology. Rates substantially lower than typical residential rates
are often available for industrial purposes, particularly when usage is as high as it is for this technology.
The industrial or commercial cost of high voltage line power varies greatly with location ranging from
as low as $0.025 per kilowatt-hour on the west coast to as much as $0.08 per kilowatt-hour in the
Midwest and east coast (3). At the time of the Demonstration in Grand Ledge, Michigan, the commercial
cost of electricity was slightly higher-$0.089 per kilowatt-hour. There was an additional monthly service
fee of $6.50. These charges reflect the local cost for electricity. At other sites, this cost may differ. Based
on information gathered during the Demonstration, the Geosafe ISV process requires approximately 0.37
kWh of electricity for each pound of soil melted (approximately 0.72 MWh per ton). This value is used
in the cost estimate presented although it is slightly lower than the typical value reported by Geosafe of
0.50 kWh per pound (1 MWh per ton). The total electrical usage for the system when treating nine five-
foot deep cells at a rate of 370 MWh per pound of soil is approximately 2,200 MWh. When the cell
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depth is increased to 15 feet, approximately 5,900 MWh are required for nine cells, and when the cell
depth is 20 feet, approximately 7,700 MWh are required for nine cells. The power consumption per
pound of soil reported here is based on Demonstration results-soil with a density of approximately 3,600
pounds per cubic yard (1.8 tons per cubic yard) and 16 percent moisture. The density and moisture
content of the actual soil treated may cause this value to vary. Additional electricity is required for power
in the office and process trailers. However, this is negligible compared to the amount of power required
to melt the soil and has therefore been ignored in these calculations. A diesel generator may be utilized
when power lines are inaccessible. Cost for use of diesel generators is equivalent to approximately $0.083
to $0.13 per kilowatt-hour (3)
Natural gas is utilized by the thermal oxidizer. Approximately one million cubic feet of natural gas are
required to treat the off-gas generated from each B-foot cell when using a thermal oxidizer with a
capacity of 10,000 standard cubic feet per minute. This amount will vary slightly with the time required
to treat a cell, but the overall effect on the total cost is negligible, and thus the same natural gas
requirements have been assumed for each of the three cases. The local cost for natural gas in Grand
Ledge, Michigan at the time of the Demonstration was $10 per month plus approximately $0.00040 per
cubic foot.
Locally, water rates were $21 per quarter (three months) plus a sewage fee of $0.0029 per gallon at the
time of the Demonstration. Water usage fluctuated throughout treatment based on system performance,
soil moisture content, and current weather conditions. On the average, approximately 3,500 gallons of
water were required for each cell treated during the Demonstration (cell depth 15 feet). When the cell
depth is 5 feet, water consumption per cell is estimated to be 2,000 gallons per cell, and when the cell
depth is 20 feet, water consumption is estimated to be 4,500 gallons per cell.
Effluent Treatment and Disposal Costs
The stack gas and the scrubber liquor are the only effluent streams anticipated to be generated as a result
of typical treatment using the Geosafe ISV process. Depending on the on-site contamination and the
ARARS, these streams may be permitted for discharge. In most instances, when a thermal oxidizer is part
of the off-gas treatment train, emissions may be released directly to the atmosphere without further
treatment. A likely scenario for the scrubber liquor is collection and disposal as a residual waste although
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Geosafe claims that scrubber liquor may be recycled to subsequent melts. During the Demonstration,
scrubber liquor was collected as disposed of as a residual waste, therefore these costs are covered under
"Residuals and Waste Shipping and Handling Costs," At the Parsons site, an additional effluent stream
was encountered when the logistics of treatment required a groundwater diversion system to be installed,
This diverted water was permitted for discharge after carbon filtration. The costs for treatment of this
additional effluent stream were unique to the Parsons site and have been excluded from this cost estimate.
3.3.9 Residuals and Waste Shipping and Handling Costs
The primary process residua! generated by the Geosafe ISV technology is the vitrified mass. This material
is generally left intact and in place at the conclusion of treatment. The molten mass may take one to two
years to cool completely. There are no costs associated with the disposal of the vitrified mass. In some
instances, the treated material may be left uncovered in order to cool more rapidly and thus induce
crystallization and fracturing of the mass. This may be a desirable practice if the vitrified mass is to be
removed from the treatment site. Costs for the removal of the vitrified mass are dependent on the ease
of handling the material (which is in turn dependent on the degree of fracturing achieved) and have not
been included in this cost estimate.
A number of secondary process residuals and waste streams are generated by the Geosafe technology.
The disposal of these streams requires approximately one week (seven days) of preparation (eight hours
per day). Personnel requirements are limited to three local workers and the off-site assistance of one
person from the Geosafe home office. (See "Labor Costs" for specific labor rates.)
The liquid waste streams include scrubber liquor and decontamination liquid. The scrubber liquor was
discussed briefly above as an effluent stream, but since the scrubber liquor was not discharged at the
Parsons site, the cost of its disposal is included in this category. The amount of scrubber liquor generated
is dependent on the nature of the treatment media. High levels of contamination and/or soil moisture
content may result in large quantities of scrubber liquor. For treatment of 5-foot cells, it is estimated that
approximately 3,000 gallons of scrubber water (including the initial charge of water to the scrubber) are
generated per cell. The amount of scrubber liquor generated at the Parson site was highly variable from
cell to cell, but an average of approximately 8,000 gallons of scrubber water (including the initial charge)
were generated for treatment of 15-foot cells. It is estimated that approximately 10,000 gallons of
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Geosafe claims that scrubber liquor may be recycled to subsequent melts. During the Demonstration,
scrubber liquor was collected as disposed of as a residual waste, therefore these costs are covered under
"Residuals and Waste Shipping and Handling Costs." At the Parsons site, an additional effluent stream
was encountered when the logistics of treatment required a groundwater diversion system to be installed.
This diverted water was permitted for discharge after carbon filtration. The costs for treatment of this
additional effluent stream were unique to the Parsons site and have been excluded from this cost estimate.
3.3.9 Residuals and Waste Shipping and Handling Costs
The primary process residual generated by the Geosafe ISV technology is the vitrified mass. This material
is generally left intact and in place at the conclusion of treatment. The molten mass may take one to two
years to cool completely. There are no costs associated with the disposal of the vitrified mass. In some
instances, the treated material may be left uncovered in order to cool more rapidly and thus induce
crystallization and fracturing of the mass. This may be a desirable practice if the vitrified mass is to be
removed from the treatment site. Costs for the removal of the vitrified mass are dependent on the ease
of handling the material (which is in turn dependent on the degree of fracturing achieved) and have not
been included in this cost estimate.
A number of secondary process residuals and waste streams are generated by the Geosafe technology.
The disposal of these streams requires approximately one week (seven days) of preparation (eight hours
per day). Personnel requirements are limited to three local workers and the off-site assistance of one
person from the Geosafe home office. (See "Labor Costs" for specific labor rates.)
The liquid waste streams include scrubber liquor and decontamination liquid. The scrubber liquor was
discussed briefly above as an effluent stream, but since the scrubber liquor was not discharged at the
Parsons site, the cost of its disposal is included in this category. The amount of scrubber liquor generated
is dependent on the nature of the treatment media High levels of contamination and/or soil moisture
content may result in large quantities of scrubber liquor. For treatment of 5-foot cells, it is estimated that
approximately 3,000 gallons of scrubber water (including the initial charge of water to the scrubber) are
generated per cell. The amount of scrubber liquor generated at the Parson site was highly variable from
cell to cell, but an average of approximately 8,000 gallons of scrubber water (including the initial charge)
were generated for treatment of 15-foot cells. It is estimated that approximately 10,000 gallons of
53
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scrubber water (including the initial charge) are generated for treatment of 20-foot cells. The scrubber
liquor may require special handling depending upon the types and levels of contaminants being treated.
Decontamination liquid will only be generated at the conclusion of treatment when the process equipment
is decontaminated prior to transport to the next treatment site. It is estimated that approximately 5,000
gallons of decontamination water will be accumulated for disposal. Two profile samples are assumed to
be collected from each 20,000 gallons of liquid waste accumulated. A full range of analyses will be
performed on these samples to characterize the waste stream for disposal. The analytical cost per sample
is estimated at $1,500. An additional one-time $150 profile cost is also assumed for the liquid waste
stream. Disposal costs for the liquid waste stream are assumed to be $0.75 per gallon, typical for liquid
waste disposal.
Solid secondary wastes include carbon filters, scrub solution bag filters, HEPA filters, used hood panels,
and personal protective equipment (PPE). Carbon filters and HEPA filters may be recycled to maximize
their use. Other process residuals (such as used scrub solution bag filters, used HEPA filters, and PPE)
can be disposed in future melt settings to reduce the volume of these materials requiring ultimate disposal.
The number of used hood panels requiring disposal is dependent on the type and extent of contamination
at the site, the corrosiveness of the off-gases generated during treatment (as well as the corrosion-
resistance of the hood panels), and the. duration of treatment. The vendor claims that under some
treatment conditions, the life expectancy of hood panels may increase, and disposal of the panels may not
be required. The solid wastes may be combined into a single waste stream for disposal. Approximately
two 20-cubic yard roll-off bins of solid waste are generated for treatment of nine 5-foot cells; four roll-off
bins for treatment of nine 15-foot cells; and five roll-off bins for treatment of nine 20-foot cells. Disposal
costs are assumed to be $800 per 20-cubic yard roll-off bin. Profile samples are collected to characterize
the waste for disposal (two per roll-off bin), and a full range of analyses performed ($1,500 per sample)
An additional one-time $150 profile cost is also assessed to the solid waste stream.
3.3.10 Analytical Services Costs
Sampling and analysis of the system is performed on a routine basis to ensure proper performance and
compliance with regulatory limitations. It is assumed that samples are collected from every third cell
treated. Three samples of each of the following matrices are collected during each sampling episode for
54
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test soil, off-gas, scrubber liquor, and treated soil. A full range of analyses ($1,500) is performed on each
sample. If sampling is performed by an outside contractor, additional costs will be incurred, particularly
for gas sampling. Daily monitoring for fugitive emissions is also performed using a photoionization
detector or organic vapor analyzer. This monitoring equipment is available for approximately $250 per
week and is required only during treatment.
3.3.11 Maintenance and Modifications Costs
Maintenance costs are assumed to consist of maintenance labor and maintenance materials. Maintenance
labor and materials costs vary with the nature of the waste and the performance of the equipment. For
estimating purposes, the annual maintenance labor and materials costs are assumed to be 10% of the
purchased equipment capital costs. Of this, 33% is estimated to be maintenance labor and 67% is
estimated to be maintenance materials. Costs for design adjustments, facility modifications, and equipment
replacements are not included in this cost estimate. Maintenance labor is assumed to be accounted for
under "Labor Costs, " and therefore scheduled maintenance costs are limited to maintenance, materials
In addition to typical maintenance materials, the Geosafe hood panels may require replacement during
and at the conclusion of treatment. Although the panels were stainless steel, the harsh environment
beneath the treatment hood at the Parsons site demanded frequent replacement of the panels. There are
approximately 120 panels (approximately $100 each) on the hood. It is estimated that 33 % of these panels
will need replacement during treatment of nine 5-foot cells, 50% during treatment of nine 15-foot cells,
and 58% during treatment of nine 20-foot cells. Due to difficulties in decontaminating the hood panels
at the conclusion of treatment, it is Conservatively estimated that 67% of the hood panels will need
replacement for after treating nine 5-foot cells, and all 120 hood panels will need replacement after
treating nine 15- or 20-foot cells. The frequency of hood panel replacement depends on operating
conditions during treatment; Geosafe claims that the typical life expectancy of the panels is greater than
that exhibited during the Demonstration. See Appendix A of this report ("Vendor's Claims") for
additional details
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3.3.12 Site Demobilization Costs
Site demobilization is limited to the removal of all equipment from the site. Disassembly of the Geosafe
ISV system holds the same cost requirements as assembly. The disassembly process is identical to
assembly, merely performed in the reverse order. Any other requirements of the site will vary depending
on the future use of the site and are assumed to be the obligation of the responsible party. Therefore, site
cleanup and restoration costs are limited to disassembly labor charges for this cost estimate.
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SECTION 4
TREATMENT EFFECTIVENESS
4.1 Site History and Contamination
From 1945 to 1979, Parsons Chemical Works, Inc. was engaged in the mixing, manufacturing, and
packaging of agricultural chemicals at a 6.5-acre site located in Grand Ledge, Michigan. Sanitary sewage
and wash water were discharged from the packaging plant to a septic tank and tile field system. Wash
water from the operations was also released to the septic tank system, which was hydraulically connected
to a storm drain emptying into an unnamed creek near the site. Chemicals in the wash water contaminated
the soil in three areas on the site. The site, now a Superfund site, is currently owned and occupied by
ETM Enterprises, Inc., a manufacturer of fiberglass parts. ETM purchased the site from Parsons in 1979.
A total of about 3,000 cubic yards of soil were found to be contaminated with chlordane, 4,4'-DDT,
dieldrin, and mercury. Dioxins were also found on the site at very low levels. The areas of contamination
on the site were relatively shallow, reaching a maximum depth of only five feet.
4.2 Treatment Approach
After a feasibility study was conducted at the Parsons site, ISV was selected as the treatment remedy
Treatability tests on the site soil were completed by Geosafe Corporation in January 1990. The results
confirmed the suitability of the site soil and contamination for remediation by ISV, and thus ISV was
selected as the Removal Action for the Parsons Superfund site.
Because the contaminated soil at the Parsons site was shallow and located in several small areas on the
site, the soil was excavated and staged into two adjacent trenches. The trenches were constructed near
two of the contaminated soil areas, and also close to the original Parsons building. One trench was 168
feet long, and the adjacent trench was 84 feet long. Each trench was approximately 27 feet wide. A total
of nine ISV treatment cells were planned for the trenches, each a total of 27 feet by 27 feet by 15 feet
deep (See Figure 4-1)
57
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1' CONCRETE WALL INITIALLY PLANNED LOCATION Of
2'COBBLE FILL 12" DIA. ELECTRODE (TYPICAL)
CELLS
DEMONSTRATION
TEST AREA
CLEAN FILL SURROUNDS COBBLE
Figure 4-1. Plan View of Treatment Cells
The cells were built using concrete, cobble, and wood as shown in Figure 4-2. They were constructed
by trenching an area of the site, installing wooden concrete forms, and pouring concrete into the forms
to create the nine cell settings. The concrete walls were one-foot thick and 16 feet high; the top of the
walls were at ground level. A one-foot layer of cobble (which sloped up to approximately three feet in
the comers) was placed in the bottom of each cell, and approximately two feet of cobble was used to
surround the exterior of the cell forms. The cobble was used to provide a drainage pathway for water that
was known to be present on-site; the resultant flow of water was directed to two sumps and was pumped
from there to a drainage trench. After construction, the cells were lined with plastic sheeting, and then
filled with contaminated soil from the site. A layer of clean soil approximately two feet deep was placed
on top of the contaminated soil to act as a barrier between the contaminated soil and the surrounding area.
It was planned that the treatment would progress through the nine cells in a designated order. Each cell
was anticipated to require approximately seven to ten days to treat, with an additional three days required
to move the hood and off-gas treatment system between settings and start the next cell.
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4.3 Treatment Objectives
The treatment objectives for the ISV remediation at Parsons were set by EPA Region V. Final cleanup
levels for the soil were set at 1,000 fig/kg for chlordane; 4,000 Mg/kg for 4,4'-DDT; 80 /xg/kg for
dieldrin; and 12,000 /ig/kg for mercury. A major claim of the ISV developer is that the process can
significantly reduce the leaching potential of heavy metals and other inorganics from the solidified mass.
Leachability was therefore tested by conducting the toxicity characteristic leaching procedure (TCLP) on
pre- and post-treatment samples of the soil. The Federal TCLP limits (40 CFR 9261.24) were used for
comparison with test results.
4.4 Detailed Process Description
The ISV process is designed to treat soil and other earthen materials (e.g., sludge, sediments, and mine
tailings) contaminated with a wide variety of contaminants. The technology uses joule heating to melt the
waste matrix, destroying organic compounds in the process, and encapsulating the inorganic constituents
in a monolithic and leach-resistant form. In joule heating, electric current flows through the material and
transfers heat energy to the material (3)
ISV involves the heating and melting of the lithological matrix in which contamination is present. The
Geosafe process uses a square array of four 12-inch OD graphite electrodes spaced up to 18 feet part.
This allows formation of a maximum melt width of about 35 to 40 feet and a maximum melt depth of
approximately 20 feet. The electrode spacing is somewhat dependent on the soil characteristics, and the
electrodes are lowered gradually as the melt progresses. Figure 4-3 shows a typical ISV equipment layout.
A conductive mixture of flaked graphite and glass frit is placed just below the soil surface between the
electrodes to act as a starter path since dry soil is usually not electrically conductive. The soil surface
beneath the hood is then covered by a layer of insulation. The starter path facilitates the flow of current
between the electrodes until the ground matrix reaches a temperature and viscosity to conduct the current
and produce melting. At this stage, the soil warms to approximately 2,900 to 3,600°F (1,600 to
2,000°C), well above the initial melting temperature of typical soils (2,000 to 2500°F or 1,100 to
1,400°C). Temperatures at an individual electrode can reach as high as 3,300°F(1,800°C). The graphite
and glass starter path is eventually consumed by oxidation. Upon melting, most soils become electrically
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Electrode
Ctean Fill (Soil)
Figure 4-2. Cut-Away View of Treatment Cells
OFF-GAS HOOO
Zl
ttt
UTUfTYQR
OCSEL-
Ge«RA1EO
POV¥ER
PO
WER
TOEUECmOOES
^x*
^
ELEcraooe
tQCATION
J
. ^
X
1
1
w
1
4
t«
'SAOCUP'
•QASFLOW
•NATURAL
GAS
THEBMAL
OXOZEH
OFF-0AS THEATMBNT SYS7B»«
- TO ATMCWHEHE
Figure 4-3, Geosafe In Situ Vitrification Process
60
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Electrode
Clean Fill (Soil)
Figure 4-2. Cut-Away View of Treatment Cells
OFF-GAS HOOD
POWER TO ELECTRODES
/
ELECTRODE
inCATIOM
OBWATER
HEAT
NATURAL
GAS
X
OFF-GAS TREATMENT SYSTEM
TO ATMOSPHERE
Figure 4-3. Geosafe In Situ Vitrification Process
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conductive; thus, the molten mass becomes the primary conductor and heat transfer medium. As a result
of the joule heating, the inherent viscosity is lowered to approximately 100 poise. At this point, the melt
begins to grow within the soil matrix, extending radially and downward. Power is maintained at levels
sufficient to overcome heat losses from the surface and to the surrounding soil. Heating of the melt is
aided by convection currents within the melt. Heat is transferred to the adjacent soil by conduction from
the melt.
Electric power is supplied to the array of electrodes through flexible conductors. The ISV hood is
equipped with an electrode feed system that gravity feeds the electrodes downward as the melt progresses.
Initially, the electrodes are inserted approximately one to two feet below grade. As the melt becomes
established and is no longer subject to any failure in its conduction of the applied current, the four
electrodes are released and allowed to descend into the lithological matrix according to their respective
individual weights. Ideally, this will proceed until the targeted contaminants are completely enveloped
in the melt and the desired treatment depth is attained. Graphite extensions are added to the top of each
electrode according to the intended depth penetration of the melt. If processing difficulties are
encountered, the electrode feed system may "grasp" the electrodes and thus prevent their downward
movement until the difficulty is addressed.
The process can remediate contaminated soil at a rate of four to six tons per hour until a maximum mass
of 800 to 1,200 tons has been treated. The downward growth rate of the melt is in the range of one to
two inches per hour. Because soil typically has low thermal conductivity, a very steep thermal gradient
of 300 to 480°F (150 to 250°C) per inch precedes the advancing melt front. This produces a 212°F
(100'C) isotherm less than one foot away from the molten mass. The soil volume between the 212°F
isotherm and the melt is termed the "dry zone." This zone has maximum vapor permeability because it
exists without the presence of liquid water.
As the melt grows, the electrical resistance of the melt decreases. The ratio between the voltage and the
current must, therefore, be adjusted periodically to maintain operation at an acceptable power level.
Generally, the melt grows outward to a width approximately 50 percent wider than the electrodes spacing.
The molten zone is roughly a cube with slightly rounded comers on the bottom and sides; this shape
reflects the higher power density around the electrodes. Figure 4-4 presents typical process conditions.
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During processing, ISV removes the void volume present in particulate materials resulting in a volume
reduction. Further volume reduction also occurs, since some of the material present in the soil such as
humus and organic contaminants are removed as gases and vapors during processing. The overall volume
reduction (typically 20 to 50 percent), creates a subsidence volume above the melt (see Figure 4-4).
At appropriate temperature regimes within the soil surrounding the melt, or within the melt itself, the
solids and contaminants undergo changes of physical state .and decomposition reactions. The possible
dispositions of contaminants resulting from ISV processing include:
Off-Gas Collection Hood
(-0,5 to 1,0 in Water)
Controlled Air
input
Off-Gases to
Treatment
Electrode (typ)
' - 3-4 MW power level
- 0,3 to 0.4 kwh/Ib treated
Angle of Repose
Unaffected Soil
(minimum
permeability)
Conductive Heating
{matt advance rate
of 1 to 2 in/hr)
212 F Isotherm
Melt Surface
Dry Zone
• thermal gradient of
30Gto4SS F/tn
- maximum permeability
Molten Soil Region
- joule heating between electrodes
-2,900-3,6ofi F
- melt rate 4-6 tons/hr
- molten oxides and contaminants
- chemically reducing environment
• convection currents
Figure 4-4. Typical ISV Process Conditions for the Geosafe Technology
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• chemical and thermal destruction;
• removal from the treatment volume to the off-gas treatment system;
• chemical and physical incorporation within the residual product;
• lateral migration ahead of the advancing melt; and
• escape to the environment.
As the thermal gradient advances on solid or liquid organic materials, these materials are either drawn
into the melt or laterally migrate into the dry zone where the are vaporized and ultimately pyrolyzed.
Only a small fraction of vapor passes through the melt itself. The predominant pathway for vapor
movement from the treatment zone is through the dry zone adjacent to the melt. Because of gas-phase
permeability differences, the dry zone is the path of least resistance and the adjacent wet soil acts as a
barrier to outward movement of vapors. Organic pyrolysis products are typically gaseous; because of the
high viscosity of the molten material, these gases move slowly through the melt, usually on a path
adjacent to the electrodes, toward the upper melt surface. While some of these gases may dissolve into
the molten mass, the remainder move to the surface where those that are combustible react in the
presence of air. Pyrolysis and combustion products are collected in an off-gas collection hood and are
subsequently treated in the off-gas treatment system. Because of the high temperature of the melt, no
residual organic contaminants are expected to remain in their original compound form within the vitrified
product
The behavior of inorganic materials upon exposure to the advancing thermal gradient is similar to that
of the organics. Inorganic compounds may thermally decompose or otherwise enter into reactions with
the melt. Typically, the metals originally present are incorporated into the vitrified residual.
Immobilization may occur when the contaminants are incorporated into the glass network or encapsulated
(surrounded) by the glass. If large amounts of non-volatile metals are present, they may sink to the
bottom of the melt and concentrate there.
During treatment, a "cold cap" forms over the surface of the melt. This cold cap, a surface layer of
viscous molten material at the air/melt interface, helps to contain radiative heat loss. The cold cap also
performs the important function of holding volatilized wastes for possible re-incorporation into the melt.
The cold cap is penetrated by the electrodes which, themselves, are usually hot enough to maintain fluid
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behavior in directly adjacent areas. These highly fluid surface areas are common vent locations for release
of vapors and gases from the melt.
Once a melt is established, the process may be restarted after a power shutdown or loss, as long as a
molten path remains between the electrodes. If this is not the case, it will be necessary to lay a new
starter path of graphite and glass frit between the electrodes. The amount of time allowed for restart
depends on the size of the melt. A large melt (e.g., 500 tons) could allow restart even after several days.
Shutdowns during the first 48 hours of treatment are more difficult to restart and more sensitive to the
length of the outage.
The processing area is covered by an octagonal off-gas collection hood with a maximum width between
the flat edges of 60 feet. Footers, which support the hood, extend five feet past the maximum width of
the hood. The large distance between the edge of the hood and the edge of the melt is designed to enable
off-gas containment, even under worst-case subsidence conditions. Flow of air through the hood is
controlled to maintain a vacuum of 0.5 to 1 inches of water on the system. The vacuum prevents the
escape of fugitive emissions from the hood and ground surface interface. Air provides oxygen for
combustion of pyrolysis products and organic vapors. The off-gases, pyrolysis products, and air are
drawn from the hood by an induced draft blower into the off-gas treatment system. The off-gas is treated
by quenching, pH-controlled scrubbing, mist elimination, particulate filtration, and activated carbon
adsorption. A thermal oxidizer was added to the gas treatment train midway through the remediation at
the Parsons site to complete combustion of organic compounds from the melt and help reduce odors. A
backup gas treatment system is also present and is designed to be activated automatically in case of power
interruption. The backup system employs a diesel-powered generator, blower, mist cooler, filter, and
activated carbon column.
Once power to the electrodes is shut off, the melt begins to cool. In most cases, no attempts are made
to force cooling of the melt; slow cooling is expected to produce a vitreous (amorphous) and micro-
crystalline structure. Removal of the hood is normally accomplished within 24 hours after power to the
electrodes is discontinued. The used graphite electrodes are severed near the melt surface and are left
within the treated monolith. After the off-gas hood is removed and the electrodes are severed, the
subsidence volume is filled to the desired depth with clean backfill. When melt locations are contiguous,
a single large monolith will ultimately be produced. In instances where removal of the vitrified mass is
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anticipated, the treated area may be left uncovered to speed the cooling process and induce shrink-
cracking of the surface. This aids the fracturing of the mass prior its removal.
4.5 Testing Methodology
The EPA Risk Reduction Engineering Laboratory (EPA-RREL) chose the former operational site of
Parsons Chemical Works, Inc. (the Parsons site) in Grand Ledge, Michigan for the evaluation of the
Geosafe ISV process as part of the SITE Program. The site was known to be contaminated with low
levels of pesticides and metals and was the first full-scale implementation of the ISV technology to treat
hazardous wastes. Region V of the EPA had also selected the Geosafe technology as part of a removal
action for the Parsons site. The SITE Program, under the direction of EPA-RREL, used this opportunity
to gain additional valuable information regarding the ISV technology. The SITE Demonstration and the
Region V cleanup operations were implemented in conjunction with one another during treatment. The
sampling analysis and process monitoring performed as part of the SITE Demonstration were designed
to supplement those already planned and performed by Region V. For informational purposes, some data
from EPA Region V is presented in this report; these data were not used to evaluate the SITE
Demonstration objectives
Under the SITE Program, the goal of this Demonstration was to determine the effectiveness of treatment
and to evaluate the technology from an economic and performance standpoint. The developer of this
technology (Geosafe) claimed that the ISV system could obtain a destruction and removal efficiency
(DRE) of 99.99% for organic compounds within the soil and can incorporate inorganic compounds and
metals within the residual vitrified product. Pre-treatment chemical concentrations were too low to
evaluate this claim appropriately. Instead, the objectives presented in the following paragraphs were
established.
The primary objective of the Demonstration was to determine whether EPA Region V cleanup criteria
could be met. The Demonstration of the ISV technology was designed to allow evaluation of the ability
of the technology to meet regulatory criteria for the major pesticides present and mercury. In addition,
the leaching characteristics of the untreated and the treated waste were evaluated.
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Critical objectives are those objectives which are important to developer's claims and those which can
be evaluated at this site. Secondary (or non-critical) objectives are those which are of interest to future
applications of ISV technology but do not relate directly to the developer's claims. Other objectives, such
as DRE, are not considered here but are expected to be included at future sites where levels of
contamination are higher. The Demonstration objectives as specified in the QAPP were:
Critical Objective:
• To determine if final soil cleanup levels set by the EPA Region V were achieved. These
specified cleanup levels were 1,000 peg/kg for chlordane, 4,000 ^g/kg for 4,4'-DDT, 80
jig/kg for dieldrin, and 12,000 /ig/kg for mercury.
Secondary Objectives:
• To evaluate the teachability characteristics of chlordane, 4,4'-DDT, dieldrin, and mercury
in the test soil using the TCLP and determine whether the teachability characteristics of
these compounds in the vitrified residue met the regulatory limits specified in 40 CFR
$261.24. (Note: Only mercury and chlordane are listed in 40 CFR $261.24.)
• To determine the approximate levels of dioxins/furans, pesticides (specifically chlordane,
4,4'-DDT, and dieldrin), mercury, and moisture in the test soil.
• To characterize the liquid residues (scrubber water) of the process with respect to
pesticide and mercury concentrations.
• To evaluate emissions from the process
• To identify the operational parameters of the technology
• To develop operating costs and assess the reliability of the equipment
• To examine potential impediments to the use of this technology including technical,
institutional, operational, and safety impediments.
A Demonstration Plan and Quality Assurance Project Plan (QAPP) were prepared to specify technical
project objectives to be used in evaluating the Geosafe ISV technology at the Parsons site under the SITE
Program. The QAPP specified the procedures for sampling and analysis to evaluate project objectives.
The sampling plan required test soil sampling before and after treatment, scrubber water sampling before
and after treatment, and gas sampling of the emissions to the atmosphere during treatment.
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To evaluate the critical objective for this project, the treated soil samples analyses for pesticides and
mercury were designated as critical analyses. Other non-critical measurements were performed to
characterize the process. The following sections present a discussion of the data collected in support of
this evaluation.
Soil placed into the treatment cells was sampled by EPA Region V while the cells were being filled.
These samples were composites collected from random locations throughout the cells. Based upon Region
V data, Cell 8 contained the highest levels of organic and inorganic contaminants, therefore this cell was
selected for evaluation by the SITE Program. In May 1993, five additional grab samples were collected
by EPA Region V, three of which were analyzed by the SITE Program for pesticides and mercury. The
TCLP was also performed on these samples, and the leachate was analyzed for pesticides and mercury.
These samples were intended to provide information for use in development of SITE Demonstration
objectives. The results are presented in Table 4-1. The data suggest that the staged soil is not very
homogeneous before treatment, exhibiting wide variations in contamination levels.
Based upon these results, it was noted that the contaminant levels were not high enough to warrant a full
statistical-based sampling strategy to determine the average soil concentration of target contaminants for
use in DRE, mass balance, or percent removal calculations. Therefore, the SITE Program elected to
collect a limited number of soil samples (three plus one field duplicate) from the test cell to evaluate pre-
treatment soil conditions. Pre-treatment soil conditions were not as significant as post-treatment soil
conditions since determination of DRE was not an objective, so the heterogeneity of the pre-treatment
soil was not a concern.
Composite samples of the soil in Cell 8, the cell treated during the Demonstration, were collected and
analyzed before treatment was initiated on this cell at a time when sampling did not interfere with Region
V activities in adjacent cells. A drill rig equipped with a 2-inch diameter split spoon sampler was used
to collect sample cores from three separate boreholes at three locations within the cell. An additional
borehole was drilled to obtain the field duplicate samples. This boring was located as close as possible
to the primary boring. All samples were collected from depths between 4 and 15 feet below land surface.
The soil recovered from all split spoons of a particular boring were composited together and aliquoted
for the selected analyses. Samples from the cell were analyzed for pesticides (chlordane, 4,4'-DDT, and
dieldrin), dioxins/furans, mercury, glass formers (alumina and silica), and conductive cations (lithium,
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Table 4-1. Results of Analysis of Pre-Treatment Screening Samples Collected from Cell 8
Analytical Parameter
Sample
Composite*
1'
3f
5'
TCLP 1*
TCLP 2f
TCLP 3f
Units
Mg/kg
Mg/kg
Mg/kg
Mg/kg
Mg/L
/tg/L
Mg/L
4,4' -DDT
72,000 J
1,100
4,800
830
0.11
1.2
< 0.087
Dieldrin
12,000 J
2,600
2,800
180
4.4
6.3
1.5
Chlordane
2,000 J
<8.0
<8.0
<8.0
<0.26
<0.26
<0.26
Mercury
12,000
3,900
15,000
1,400
< 0.00048
O.00048
< 0.00048
Random composite collected during filling of the cell. Sample collected in February 1991 by
Ecology and Environment.
Samples collected in May 1993 for SAIC by EPA Region V representatives. Five samples were
collected, but only three were analyzed.
Value reported is less than the reporting detection limit but greater than the method detection
limit. Value is an estimate.
Compound not detected at or above presented value (detection limit).
potassium, sodium). Samples were also subject to the TCLP for the target pesticides and mercury. During
sampling, the geological characteristics of the borings were recorded. The physical parameters of grain
size and permeability were determined. To evaluate the volume reduction from treatment, moisture
content and test soil density (on a dry basis) were measured using a drive cylinder method. In this
procedure, the sample is obtained in situ by driving a cylinder of known volume into the sample matrix.
The cylinder is weighed to determine density and then analyzed for moisture content. Using this
information, dry density can be calculated.
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During treatment of Cell 8, the process was visually observed and monitoring of the system was
conducted. Data were recorded at regular intervals. Stack sampling was conducted as specified in the
QAPP.
Gaseous emissions from the stack downstream of the gas treatment equipment were evaluated using both
sample collection and continuous emission monitoring techniques. Stack gas samples were collected using
Summa canisters for volatile organic compounds, and sampling trains for semivolatile organics,
pesticides, dioxins/furans, metals, hydrogen chloride, and particulate matter. Continuous emission
monitoring for oxygen, carbon monoxide, and total hydrocarbons was conducted using the on-line
equipment utilized by Geosafe to comply with operating permits. The original intent of the stack gas
sampling was to provide an indication of the composition of the gases emitted to the atmosphere. All of
the stack gas measurements were designated as non-critical. During the first few treatment settings at the
Parsons site, an offensive odor was emitted from the process. To remedy this, Geosafe modified the off-
gas treatment train to include a thermal oxidizer, thereby oxidizing the odorous compounds. Local
regulatory agencies also closely monitored process emissions and specified emission criteria. As a result
of these developments, the stack gas sampling objectives for the SITE Demonstration were modified to
evaluate if the process could operate within regulatory guidelines. The emissions of pesticides and
mercury, along with arsenic, chromium, lead, carbon monoxide, and total hydrocarbons, were designated
critical measurements. Samples of the gases emitted to atmosphere were collected after exiting the thermal
oxidizer
After treatment of Cell 8 was complete, the off-gas treatment system was allowed to run for
approximately 24 hours to remove any fugitive emissions from the melt. After this 24-hour period, the
containment hood was moved and the ambient air was monitored with an organic vapor analyzer and a
mercury analyzer. When airborne contaminant levels were determined to be safe, samples of the treated
material were collected from just below the surface of the melt. These samples were intended to provide
immediate information regarding the effectiveness of the ISV treatment.
The surface material sampled was part of the "cold cap" and was already solidified by the time the
treatment hood was moved. Samples were collected by a member of the developer's staff who, wearing
heat-insulating boots and other appropriate personal protective equipment, stood upon the subsided surface
of the melt. The sampler was supported by a lifeline held by personnel outside the melt area Samples
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of the surface material were then obtained using a decontaminated hammer to chip pieces from the cold
cap. After collection, the samples were placed in a cotton cloth and further crushed using the
decontaminated hammer. The sample pieces were thoroughly homogenized and aliquoted into sample
containers for analysis. These post-treatment surface samples were analyzed for pesticides (chlordane,
4,4'-DDT, and dieldrin), dioxins/furans, and metals. They were also subject to the TCLP for the target
pesticides and metals. In addition, density measurements were performed on the treated material.
Admittedly, these surface samples are not representative of the entire melt, but they do provide immediate
information about the treated surface material.
Additional samples of the post-treatment soil will be collected from the core of the vitrified mass after
it has completely cooled and solidified. The number of samples collected will exceed then number of
samples required to ensure statistical credibility. These samples may be collected up to two years after
the completion of treatment. It is anticipated that these samples will be collected from the center of the
treatment area using a rotary drill rig equipped with a diamond-tipped drill bit or another appropriate
method. The samples will again be analyzed for pesticides (chlordane, 4,4'-DDT, and dieldrin),
dioxins/furans, and metals and subjected to the TCLP for target pesticides and metals. The density of
these samples will also be measured. The data will be reviewed by a statistician as required. If the
samples display significant variability or the levels are higher than the cleanup objectives, then additional
samples will be analyzed. Future samples are anticipated to confirm the results obtained from the surface
samples. The results from these sample analyses will be published as an Addendum to this report.
To account for contaminants removed by the scrubber, grab samples of the scrubber water were collected
before, during, and after treatment of Cell 8. Two samples (primary and field duplicate) of water charged
to the scrubber were collected before treatment of Cell 8 (but after treatment of the preceding cells) to
provide baseline data regarding the type and quantity of contaminants present. The scrubber liquor was
also sampled to evaluate the amount and types of material accumulating during treatment. Two sets of
samples were collected after treatment commenced-one (primary and field duplicate) during a discharge
sequence, and one at the end of the test. Since the scrubber liquor waste stream may require secondary
disposal, samples were collected to characterize this liquid and to gain information on the type of material
being treated by the off-gas treatment system. All scrubber samples were analyzed for volatile organics,
semivolatile organics, target pesticides, dioxins/furans, and total metals including mercury and arsenic.
These sample analyses were not considered critical objectives for the Demonstration.
70
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4.6 Performance Data
Table 4-2 presents the post-treatment soil sample results for target pesticides, mercury, and target TCLP
analytes in comparison to regulatory limits. The table also presents summary stack emission data in
comparison with the ARARs in place at the time of the Demonstration. Standard deviations are not
presented in this table since only a limited number of samples were collected. The summary clearly
indicates that Region V cleanup objectives for the target contaminants were achieved. It should be noted
that some ARARs were achieved prior to treatment, without implementation of the technology. Both
chlordane and mercury were below the specified cleanup objectives before treatment even began. As
shown in the table, the TCLP results were well within the regulatory limits. Stack emissions were also
below the ARARs. The technology was not rigorously challenged by the low levels of contaminants at
this site, and therefore, the ability of the technology to remediate highly contaminated soil has not yet
been demonstrated. Detailed discussions regarding the analytical data in this table are presented in the
following sections.
4.6.1 Test Soil
The test soil was subjected to the chemical and physical analyses specified in the QAPP both before and
after treatment. A discussion of the results of these analyses is presented below.
4.6.1.1 Pre-Treatment Test Soil Chemical Characteristics
The results of chemical analyses of the soil are presented in Tables 4-3 through 4-6. Standard deviations
are not presented because only a limited number of samples were collected. The pesticide target analytes
were detected in the pre-treatment samples at the average levels shown in Table 4-3. Chlordane was
below the EPA Region V cleanup criteria of 1,000 /ig/kg and was not detected in any of the samples.
4,4'-DDT averaged 13,000 tig/kg, with a range of 2,400 to 23,000 iig/kg. Dieldrm ranged from 1,200
to 8,300 ^g/kg and averaged 4,600 /xg/kg. Levels of mercury in the test soil were below the Region V
cleanup criteria of 12,000 /xg/kg, ranging from 2,200 to 4,700 fig/kg and averaging 3,800 tig/kg.
The pre-treatment soil was also evaluated for the presence of dioxins and furans since these compounds
had been detected in low levels by EPA Region V at various locations of the Parsons site. The results
71
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Table 4-2. Performance Data During Demonstration Versus ARARs
Analyte
Treated Soil
Chlordane
4,4-DDT
Dieldrin
Mercury
Treated Soil TCLP
Chlordane
Mercury
Arsenic
Barium
Cadmium
Chromium
Lead
Selenium
Silver
Stack Emissions
A r*\pn if*
/** tSv'iliV*
r*"* H r A rn t n rn
v*4.u v/nni4iii
Lead
Mercury
Carbon Monoxide
Total Hydrocarbons
Units
Mg/kg
Mg/kg
fig/kg
Mg/kg
Mg/L
Mg/L
Mg/L
Mg/L
Mg/L
Mg/L
Mg/L
Mg/L
Mg/L
Ih/hr
I \J 1 i 1 1
Ih/hr
i,U/ lii
Ib/hr
Ib/hr
ppmv
ppmv
Test Result (Average)
< 80
< 16
< 16
110
< 0.50
0.18
13
440
< 5,0
< 10
1,100
< 300
< 10
< I OF-Ofi
^"> i r •"' *~rf \J\J
? 1 p.o^
i_. » 1 1^ \,/^
2.8E-05
1.1E-04
< 10
< 10
Regulatory Limit
1,000 *
4,000 *
80 *
12,000
30 **
200 **
5,000 **
100,000 **
1,000 **
5,000 **
5,000 **
1,000 **
5,000 **
.:.
f
5.9E-04 ?
150 i
100
Cleanup level specified by EPA Region V,
40CFR §261.24,
No regulatory limits specified.
Emission level specified by Michigan Department of Natural Resources.
72
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Table 4-3. Geosafe Test Soil Pesticides and Metals Data Summary*
Analyte
Pesticides +
Chlordane
4,4'-DDT
Dieldrin
Metals ++
Aluminum
Arsenic
Barium
Calcium
Chromium
Cobalt
Copper
Iron
Lead
Magnesium
Manganese
Mercury
Nickel,
Potassium
Sodium
Vanadium
Zinc
Physical Parameters -H-
Density (wet basis)
Density (dry basis)
Pre-Treatment
(us/kg)
< 80
13,000
4,600
(M8/kg)
3.1E+07
9.0E+03
3.1E+05
2.6E+07
4.1E+04
l.OE+04
7.1E+03
2.4E+07
5.0E+04
8.7E+06
6.7E+05
3.8E+03
3.4E+04
1.3E+07
6.2E+06
5.6E+04
5.6E+04
(ton/yd5)
1.8
1.5
Post-Treatment
(jag/kg)
< 80
< 16
< 16
(Hg/kg)
3.1E+05
3.1E+03
3.6E+03
l.OE+06
1.3E+04
1.9E+03
7.1E+03
2.6E+06
8.6E+03
3.2E+05
1.1E+04
3.3E+01
1.1E+04
1.1E+05
1.2E+05
1.9E+03
4.5E+04
(ton/yd3)
NA
2,0
Post-Treatment
(Hg/kg)
NA
NA
NA
(^g)
3.0E+07
6.4E+03
2.8E+05
4.8E+07
5.0E+04
5.5E+03
1.4E+04
1.6E+07
2.5E+04
1.5E+07
3.4E+05
1.1E+02
1.6E+04
1.1E+07
6.7E+06
4.3E+04
9.2E+04
(toii/yd3)
NA
NA
* - Complete data are presented in the Technology Evaluation Report,
1 - Digestion of metals by SW-846 Method 3050 and mercury- by SW-846 Method 7471,
b - Digestion by HF acid total dissolution.
+ - Data reported are average values from three primary and one duplicate sample collected.
++ - Pro-treatment data reported are average values from three primary samples collected.
Post-treatment data reported are average values from three primary and one duplicate sample collected,
< - Analyte not detected at or above presented value (detection limit),
NA - Sample not analyzed for this parameter.
73
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Table 4-4. Geosafe Test Soil Dioxins/Furans Data Summary*
Anal yte
2,3,7,8-TCDF
Total TCDF
2,3,7,8-TCDD
Total TCDD
l,2,3,7s8-PeCDF
2,3,4758-PeCDF
Total PeCDF
1,23,78-PeCDD
Total PeCDD
1,2,3,4,7,8-HxCDF
1,2,3,6,7,8 HxCDF
2,3,4,6,7,8-HxCDF
l,2,3,7,8,9_HxCDF
Total HxCDF
1,2,3,4,7,8-HxCDD
l,2,3,6,7,8_HxCDD
1,2,3,7,8,9-HxCDD
Total HxCDD
l,2,3,4,6,7,8_HpCDF
l,2,3,4,7,8,9_HpCDF
Total HpCDF
1,2,3,4,6,7,8 HpCDD
Total HpCDD
OCDF
OCDD
2,3,7,8-TCDD Equivalence
Pre-Treatment * *
(ng/kg)
< 0.88
17
6.4
9.2
< 1.7
4.5
52
1.4
7.4
< 6.2
< 5.4
3.6
0.78
53
1.5
6.3
3.2
56
32
< 2.5
130
240
430
200
2,900
17
Post-Treatment **
(ng/kg)
< 0.49
< 0.49
< 0.47
0.011
< 0.51
< 0.31
< 0.51
< 0.34
< 0.34
< 0.51
< 0.43
0.40
< 0.49
0.20
< 0.49
< 0.63
< 1.0
0.0067
< 0.60
< 0.55
0.08
0.78
0.80
< 0.77
4.3
0.034
* - Complete data are presented in the Technology Evaluation Report.
** - Data reported are average results from one primary and one duplicate sample collected.
< - Analyte not detected at or above presented value (detection limit).
74
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Table 4-5, Geosafe Soil TCLP Pesticides and Metals Data Summary*
Pre-Treatment
Analyte
Pesticides
Chlordane
4,4'-DDT
Dieldrin
Metals
Arsenic
Barium
Cadmium
Chromium
Lead
Mercury
Selenium
Silver
Sample 1
(Hg/L)
< 0,50
0,17
8,2
NA
NA
NA
NA
NA
0.050
NA
NA
Sample 2
Oig/L)
< 0.50
< 0.10
8.9
NA
NA
NA
NA
NA
0,035
NA
NA
Sample 3
(Mg/L)
< 0.50
< 0.10
6.5
NA
NA
NA
NA
NA
0.010
NA
NA
Sample i
(ug/L)
< 0.50
< 0.10
< 0.10
< 4,0
330
< 5,0
11
< 50
0.20
< 300
< 10
Post-Treatment
Sample 2
(Hg/L)
< 0.50
< 0.10
< 0.10
13
540
2.9
< 10
4,300
0.23
< 300
< 10
Sample 3
(ng/L)
< 0.50
< 0.10
< 0.10
31
550
4.1
5.8
15
0.090
< 300
< 10
* - Complete data are presented in the Technology Evaluation Report.
NA - Sample not analyzed for this compound.
< - Analyte concentration is less than or equal to presented value (detection limit).
in Table 4-4 indicate that dioxin/furan contamination was extremely low with a 2,3,7,8-TCDD
equivalency, averaging 17 ng/kg with a range between. 14 and 19 ng/kg.
The pre-treatment soil samples were subjected to the toxicity characteristic leaching procedure to evaluate
the teachability of the critical target anaiytes before treatment (see Table 4-5), Only chlordane and
mercury are listed, in 40 CFR §261,24 where TCLP limitations are specified. Chlordane was not detected
in any of the TCLP samples, and mercury was well below regulatory limits. However, low levels of 4,4'-
DDT were detected between less than 0.10 and 0.17 jig/L, and dieldrin was detected between 6,5 and.
8.9
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Table 4-6. Geosafe Pre-Treatment Test Soil Conductive Cations and Ultimate Analysis Data*
Analysis Result units
Conductive Cations* *
Aluminum 33,000 mg/kg
Lithium 18 mgfkg
Potassium 12,000 mgn
-------
Table 4-6. Geosafe Pre-Treatment Test Soil Conductive Cations and Ultimate Analysis Data*
Analysis Result units
Conductive Cations**
Aluminum 33,000 mg/kg
Lithium 18 mg/kg
Potassium 12,000 mg/kg
Silicon 280,000 mg/kg
Sodium 6,600 mg/kg
Ultimate Analysis* * *
Carbon 1.3 %
Nitrogen 0.23 %
Oxygen 7.0 %
Sulfur 0.010 %
• - Complete data are presented in the Technology Evaluation Report.
• * - Data reported arc average values from one primary and one duplicate sample collected.
• ** - Data reported are average values From three primary samples collected.
An important consideration when using the in situ vitrification technology is the confirmation of sufficient
amounts of conductive cations and glass-forming metal oxides in the test soil to allow soil melting and
subsequent formation of a stable monolith. For the SITE Demonstration, inductively coupled plasma
(TCP) analyses using standard SW-846 procedures were conducted on the pre-treatment test soil to
evaluate these parameters. The results are summarized in Table 4-6. Geosafe typically uses an X-ray
diffraction technique rather than ICP analyses to evaluate these parameters before treatment. Before the
onset of remediation at Parsons site, Geosafe independently determined that the concentrations of these
materials were high enough to allow the Parsons soil to be vitrified without supplemental oxide addition.
During the processing of the test cells prior to the cell selected for the Demonstration, odor problems
were observed. Because of the odor, Region V and Geosafe investigated potential sources of the problem.
Geosafe suspected sulfur as the culprit since site records indicated that sulfur was previously used at the
Parsons site, and low concentrations of sulfur-based compounds in the exhaust gas are often very
odorous. The SITE Program analyzed some of the pre-treatment samples using an ultimate elemental
analysis technique to evaluate the sulfur content of the soil. These analyses were not originally planned
76
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as part of the Demonstration. As noted in Table 4-6, some sulfur was present in the pre-treatment soil,
but at very low levels. To solve the odor problem, Geosafe added a thermal oxidizer to the end of the
off-gas treatment train to polish and completely combust partially oxidized melt gases. The thermal
oxidizer was effective in removing melt odors. The ultimate source of the odor was never positively
identified.
Additional studies were conducted on the pre-treatment test soil after learning that arsenic, lead, and
chromium were being detected in stack gas samples collected by EPA Region V and in HEPA filter
samples. The SITE Program elected to make these metals critical analytes in the stack gas samples since
their emission to the atmosphere may be a human health risk. Because of this decision, samples of the
pre-treatment test soil were analyzed to evaluate metal content within the soil. The soil was analyzed for
standard ICP metals and arsenic (using a graphite furnace method). The results of these analyses are
presented in Table 4-3.
4.6.1.2 Post-Treatment Test Soil Chemical Characteristics
In the laboratory, all vitrified soil samples were ground into a fine powder before digestion and/or
teachability testing was performed. The samples were ground in a comminution device specifically
designed to prepare laboratory samples by minimizing heat effects (friction of grinding) and sample
contamination. The laboratory was instructed to grind portions of the treated soil that were most
representative of the center of the treated area, not the cold cap. The cold cap was easily distinguished
by the amount of entrained bubbles in the vitrified sample. Solid (bubble-free) portions of the melt were
selected for analyses since they probably best represent the final product.
Samples of the ground vitrified material were extracted and analyzed for pesticides using SW-846 Method
8080. The results of these analyses are summarized in Table 4-3. The results indicate that the technology
met the removal criteria for the organic contaminants of interest. As noted by the data, all pesticides were
below their detection limits in each of the samples. Table 4-3 shows that 4,4'-DDT was reduced from
an average concentration of 13,000 /ig/kg to less than 16 /ig/kg. Dieldrin was reduced from 4,600 uglkg
to less than 16 /tg/kg. Since chlordane was not detected in any of the pre-treatment samples, the ability
of the technology to treat this compound cannot be evaluated as part of this Demonstration.
77
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Metal analyses were performed using two different digestion procedures—SW-&46 Method 3050 (7471
for mercury) and a microwave procedure using a mixture of hydrofluoric, nitric, and hydrochloric acids
to obtain total dissolution of the sample. The data for both of these analyses are summarized in Table 4-3.
As noted in the table, the metal,concentrations detected by the microwave digestion procedure are much
greater than those found in the standard procedure since the microwave digestion with hydrofluoric acid
is more agpessive and provides a better dissolution of the vitrified soil. Comparison between the two
samples is assumed to be valid because aliquots from the same sample were used for both analyses. The
only metal which does not appear to have been recovered at higher concentrations in the microwave
procedure was lead. Lead recoveries may have been impacted by sample detection limits. The data
suggest that most of the metals are retained within the vitrified solid after treatment. However, due to
the limited data set, it is difficult to accurately draw this conclusion pertaining to any specific mete!
because of sample and analytical variability. Metals were not the primary focus of this Demonstration.
Mercury concentrations that were determined using the microwave-digested samples may not be accurate.
During the QA review of these data, it was noted that some signal enhancement or depression may have-
occurred. A National Institute of Standards and Technology (NIST) fly ash sample was analyzed with
routine samples. This sample exhibited high recovery and matrix spike samples were biased low using
the microwave procedure. Therefore, mercury concentrations obtained using standard SW-846 digestion
and analytical procedures may provide a better indication of mercury concentrations since all associated
quality control data was acceptable. The data from either procedure, however, clearly indicate that the
regulatory limits for mercury levels in soil were easily achieved. Other metal concentrations closely match
the pre-treatment soil samples (hydrofluoric acid digestion method) with the exception of mercury and
perhaps arsenic (see Table 4-3). This is not surprising given the relative volatility of these metals at high
temperatures. It was not possible to thoroughly evaluate the ability of the process to retain other metals
due to the limited number of samples collected. • •
Some of the ground vitrified samples were subjected to the TCLP to evaluate the teachability of the
critical analytes after treatment. TCLP results are presented in Table 4-5 (target pesticides and regulated
metals only). As noted by the results, all samples were below the regulatory criteria for the metals
and chlordane, however, no firm conclusion can be stated regarding chlordane since this compound was
below its detection limit before treatment. Leachable levels of the pesticides dieldrin and 4,4*-DDT were
reduced to non-detectable levels in the leachate. One of the three samples contained leachable levels of
ft
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lead at 4,300 ^g/L which is close to the regulatory limit of 5,000 /ig/L. The reason for this single data
outlier is not clear, especially since lead was not present at high levels in the test soil and was 50 jig/L
or less in the other two samples. The TCLP was not performed for regulated metals other than mercury
during the pre-treatment sampling event. Therefore, no conclusive statements can be made regarding the
technology's impact on teachability characteristics of these metals (pre- and post-treatment comparison).
Dioxin/furan samples of the treated material collected suggest that these compounds were reduced to
levels much lower than those found in the samples of the soil before treatment. This evaluation can be
made by comparing the 2,3,7,8-TCDD equivalence calculations on pre- and post-treatment soil (see Table
4-4). The data table indicates that 2,3,7,8-TCDD equivalences were reduced from an average of 17 ng/kg
to 0.034 ng/kg. The decrease of the equivalences appears to be real since the concentrations of the
individual isomers seem to have been reduced.
4.6.1.3 Pre-Treatment Test Soil Physical Characteristics
Physical properties of the test soil were investigated as part of the Demonstration. The soil was a sandy
clay-like material containing approximately 45 % of material with a grain size greater than 0.1 mm. The
remainder of the test soil consisted of some finer grain sands. The detailed results of the grain size
measurements and the geological information gathered during sampling are found in an appendix of the
accompanying Technology Evaluation Report. Table 4-3 presents the results of the soil density
measurements on both a wet and a dry basis. It should be noted that the pre-treatment samples were
collected in July 1993 and the Demonstration did not commence until late March 1994. It is unlikely that
the percent moisture values (used to determine soil density on a dry basis) obtained from the pre-
demonstration samples are identical to the actual moisture content of the soil at the time of treatment.
However, sampling logistics required pre-treatment samples to be collected well in advance of treatment,
while the test cell was not covered by the hood and before directly adjacent cells were treated.
4.6.1.4 Post-Treatment Test Soil Physical Characteristics
Samples of the post-treatment soil were also collected to evaluate the density of the treated material.
These data, along with pre-treatment dry density information were used to evaluate the volume reduction
upon treatment (Table 4-3). Dry density was used in these calculations in order to compare pre- and
79
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treatment data. It was assumed that sample moisture was contained in the porosity of the soil and, upon
driving the moisture off during treatment, no appreciable volume reduction would occur. The result of
this evaluation indicated that, on a dry basis, a volume reduction of approximately 30% occurred as a
result of treatment. Vendor claims for volume reduction as a result of treatment are calculated somewhat
differently; the vendor should be contacted if additional information regarding this claim is desired.
4.6.2 Scrubber Liquor
At the time of the SITE Demonstration, Geosafe had completed five melt settings. Before the start of the
SITE Demonstration (treatment of Cell 8), the off-gas treatment system was prepared with fresh HEPA
filters and activated carbon. The scrubber system was also drained, cleaned, and charged with fresh
water. The results of analysis of the scrubber water samples for organics, metals, and dioxins/furans are
presented in Tables 4-7, 4-8, and 4-9, respectively.
4.6.2.1 Pre-Treatment Scrubber Liquor
The pre-treatment scrubber samples, obtained from the scrubber tap, were slightly brown and cloudy
from suspended and dissolved solids which remained after cleaning. The results of the pesticide analyses
(Table 4-7) indicated that there were no traces of chlordane or 4,4'-DDT in the scrubber solution. The
primary and duplicate samples both showed approximately 3.0 pg/L of dieldrin before treatment. These
results indicate that some of the dieldrin was escaping the vitrification process during treatment of cells
previously remediated. This loss can probably be attributed to volatilization of the pesticide within the
dry zone of the approaching melt
Volatile and semivolatile scrubber water data that were obtained before the start of the Demonstration are
summarized in Table 4-7. The volatile pre-treatment scrubber samples contained ketones (specifically
acetone and methyl ethyl ketone) and some benzene. Benzene was detected in the scrub solution at a
concentration of approximately 15 jxg/L. Samples analyzed for semivolatile organics before testing
indicated that there were low levels (approximately 2.0 to 50 pg/L) of polynuclear aromatic hydrocarbon
(PAH) compounds along with some moderate levels (approximately 100 to 400 Mg/L) of phenolic
compounds in the scrubber before the test.
80
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Table 4-7. Gcosafe Scrubber Water Organics Analysis Summary Data*
Pre-Treatment**
AMJyte (Mg/L)
Pesticides
ChJordane
4,4' -DDT
Dieldrin
Volatiks
Ace tone
Benzene
Methyl ethyl ketone
Semivolatiks
Acenaphthylene
Anthracene
Bcnz(a)anthracene
Bcnz(a)pyrene
Bcnzo(b)fluoranthene
Benzo(g,h,i)perylene
Benzo(k)fluoranthene
Benzoic acid
chrysene
Di-n-butylphthalatc
Dibcnzofuran
2,4-Dimethylphcnol
bis(2-cthylhexyl)phthalate
Fluoranthene
Fluorcnce
Indenol 1,, 2,3cd)pyrcne
2-Methylnaphthalene
4-Methylphenol/3-Metfaylphenol
2-Methylphenol
Naphthalene
4-Nitrophenol
Phenanthitne
Phenol
Pyrene
< 5.0
C 1.0
3.0
450
15
90
2.1
9.3
21
3.2
17
1.5
17
< 50
39
1.2
13
34
6.6
33
6.5
1.2
7.3
150
90
33
3.6
41
380
24
During Treatment**
(H8/L)
< 50
< 10
< 10
1,500
21
200
< 100
< 100
11
< 100
< 100
< 100
< 100
22.000
20
< 100
8.0
< 100
< 100
29
6.1
< 100
< 100
690
345
31
6,100
43
5.100
2Q
Post-Treatment***
(Mg/L)
< 50
< 10
10
2.ooo
24
310
< 100
< 100
18
< 100
< 100
< 100
< 100
11.000
33
< 100
15
< 100
c 100
53
10
< 100
< 100
3,100
660
31
2,6QO
78
11,000
36
• - Complete dara are presented in the Technology Evaluation Report.
• * - Data reported are average values from one primamy an one duplicate sample collected.
***- Data reported are from one primary sample collected.
< - Analyte not detected at or above presented value (detection limit).
81
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Table 4-8. Geosafe Scrubber Water Metals Analysis Summary Data*
Analyte Pre-Treatment** During Treatment** Post-Treatment*
(Hg/L)
-------
Table 4-9. Ckosafe Scrubber Water Diojcins/Furans Analysis Data"
Pit-Treatment**
AnaJyte (Hg/L)
2,3,7.8-TCDF
Total TCDF
2,3,7,8-TCDD
Total TCDD
1,2,3,7,8-PeCDF
2,3,4,7,8-PeCDF
Total PeCDF
1,2,3,7,8-PeCDD
Total PeCDD
1 ,2,3,4,7, 8-HxCDF
1,2,3,6,7,8-HxCDF
2,3,4,6,7,8-HxCDF
1,2,3,7,8.9-HxCDF
Total HxCDF
1,2,3,4,7,8-HxCDD
1,2,3,6,7,8-HxCDD
1,2,3,7.8,9-HxCDD
Total HxCDD
1,2,3,4,6,7,8-HpCDF
1,2,3,4,7,8,9-HpCDF
Total HpCDF
1, 2,3,4,6,7, 8-HpCDD
Total HpCDD
OCDF
OCDD
2,3,7,8-TCDD Equivalence
2.1E-04
4.6E-Q3
3.2E-04
1.6E-02
< 5.7E-04
2.5E-04
1.9E-03
8.3E-04
1.6E-02
2.1E-04
2.1E-04
1.4E-04
< l.OE-04
1.4E-03
4.2E-04
5.6E-04
3.9E-04
1.3E-02
4.1E04
< l.OE-04
4.3E-04
2.7E-03
6.61-03
1.5E-W
3.7E-G3
l.OE-03
During Treatment*
C^ig/L)
1.4E-04
3.0E-03
1.4E-04
4.7E-03
< 2.6E-G4
I.3E-04
1.3E-03
2.8E-04
4.7E-03
< l.OE-04
5.3E-GS
4.3E435
< l.OE-04
2.6E-04
1.2E-04
1.8E-04
1.7E-04
3.6E-03
9.0E-05
< l.OE-04
9.0E-05
9.3E4M
2.2E-03
3.0E-OS
1.6E-03
4.2E^M
Post-Treatment***
(Hg/L)
3.5E-04
7.8E-03
3.0E-04
1.4E-02
2.3E-04
3.3E-04
4.3E-03
6.2E-04
9.5E-G3
< l.TE-04
< 1.5E-04
1.2E-04
< i .OE-04
6.6E-04
2.8E-04
4.1E-04
1.8E-04
6.9E-03
2.6E-4M
< l.OE-04
2.6E-04
2.3E-03
5.3E-03
8.3E-05
4.0E-03
9.5E4M
* - Complete data are preseattsd in the Technology Evaluaticnj Repwt,
** - Data reported ait average values from one primary and one duplicate sample collected.
*** - Data reported are from one primary sample collected.
< - Analyte not detected at or above presented value (detection limit).
83
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The pre-treatment scrubber water was also analyzed for the presence of dioxins and furans. There were
no appreciable levels of these compounds detected (2,3,7,8-TCDD equivalence was 1.0 x 10"3iig/L).
The metals data for the scrubber water is summarized in Table 4-8. Some residual metals were present
in the scrubber solution in the form of either dissolved or precipitated salts. As noted by the data,
moderate levels of arsenic, chromium, lead, and mercury were present at the beginning of the
Demonstration. Sodium hydroxide was used in the scrubber to neutralize acid vapor from the melt and
to assist in the precipitation of dissolved metals; therefore, the average sodium concentration in the pre-
treatment scrubber water was 110,000 itg/L.
4.6.2.2 Scrubber Liquor During and After Treatment
No target pesticides were detected in samples collected from the scrubber sump discharge during
treatment. These results are summarized in Table 4-7. The samples required a dilution, and the detection
limits achieved for the pre-treatment samples could not be achieved due to chromatographic interferences.
The sample collected at the end of the Demonstration contained dieldrin at a concentration of 10 tig/L.
This value was the same as the reporting detection limit of this sample. The positive identification of
dieldrin suggests that some of this compound is not thermally decomposed by the vitrification process and
must be treated by the off-gas treatment system.
Post-treatment scrub solution samples analyzed for volatile and semivolatile compounds required dilution
to reduce chromatographic interferences (see Table 4-7). The concentration of benzene in the scrubber
liquor did not appear to change significantly during treatment while increases in concentrations of other
volatile analytes (especially acetone and methyl ethyl ketone) were observed. The post-treatment samples
showed increases in the concentrations of the phenolic compounds and nitrophenols. These compounds
were present in the post-treatment scrubber liquor in concentrations ranging from approximately 650 to
11,000 jug/L. Benzoic acid was also detected at 11,000 /xg/L.
The post-treatment scrubber water was also analyzed for the presence of dioxins and furans. No
appreciable levels of these compounds were detected in the samples (see Table 4-9), and in most cases,
the concentrations detected would not be a regulatory concern. The scrubber concentrations were on the
84
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order of 1.0 x 10~Vg/kg2,3,7,8-TCDD equivalence for pre-treatment, blowdown, and post-treatment
samples
The metal analyses of the scrubber water during and after treatment indicated that some mercury (a target
analyte) was present in the scrub solution (Table 4-8). However, in comparison to pre-treatment samples,
there was no net increase beyond what may be attributed to analytical error. Reductions and/or no
significant change were observed for many of the metals. This was most likely due to the addition of
sodium hydroxide to the scrubber solution which was used to neutralize acid gases and assist in the
precipitation of dissolved metals. Treatment of metal vapors by the scrubber probably resulted in
precipitable salts which were removed in the scrubber filtration system. Significant increases were noted
in aluminum, antimony, potassium, selenium, thallium, and zinc. These metals do not readily form
precipitable salts at the pH conditions under which the scrubber was operating.
463 Stack Gas
Stack gas samples for the parameters specified in the QAPP were collected during treatment of Cell 8.
The stack gas was also monitored continuously for oxygen, carbon monoxide, and total hydrocarbons.
Because pesticides were known to be present in the soil, pesticide emissions were evaluated by the
analysis of samples collected by three primary and one duplicate sample train. The soil concentrations
were too low to allow evaluation of a destruction and removal efficiency (DRE) claim. Even so, any
detectable quantity of pesticides in the stack gas would indicate a low DRE for these compounds. The
results of the pesticide stack samples are presented in Table 4-10. As shown in the table, none of the
target pesticides were detected in the stack gas.
Samples collected for volatile and semivolatile analyses did not contain any significant target compound
hits. The volatile samples were obtained using a time-integrated Summa@ canister sampling technique.
The results of these analyses are summarized in Table 4-10. Since both volatile and semivolatile samples
were analyzed using gas chromatography/mass spectrometry, a search of the 10 largest non-target
compounds were conducted. None of the unknown responses were positively identified; these compounds
were, therefore, classified as unknown hydrocarbons. The unknown compounds were present at negligible
levels. The emission data corresponds well with the total hydrocarbon measurements.
85
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The stack emissions of dioxins/furans was very low during testing. Most of the target isomers were not
detectable in the stack samples. For the two samples (primary and duplicate), the 2,3,7,8-TCDD
equivalences were 1 .O x 10'6 and 2.8 x 10"8 /ig/m3. Complete data are presented in the Technology
Evaluation Report.
To characterize metal emissions, samples were collected using three primary and one field duplicate
multiple metals sample train. The results of these samples are presented in Table 4-11. Total metals
emissions were calculated by summing the vapor phase and solid phase contributions. In cases where the
vapor phase or solid phase emissions were not detected at or above the detection limit, the detection limit
was used in the calculations. All metals emissions were in compliance with the established regulatory
guidelines. The majority of the mercury emitted from the process was in the vapor phase; levels near
Table 4-10. Geosafe Organic Stack Emissions Summary Data*
Result
Analyte (ng/m3) (Ib/hr)
Pesticides**
Chlordane
4,4'-DDT
Dieldrin
Semivolatiles***
Benzole acid
Di-n-butylphthalate
Diethylphthalate
bis(2-ethylhexyl)phthalate
< 1.4
< 0,28
< 0.28
23
1.0
0.73
2.5
< l.OE-05
< 2.0E-06
< 2.0E-06
1.6E-04
7.2E-06
5.0E-06
I.7E-05
* - Complete data are presented in the Technology Evaluation Report.
** - Data reported are results from three primary and one duplicate sample collected
*** - Data reported are results from one primary and one duplicate sample collected.
< - Analyte not detected at or above presented value (detection limit).
86
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Table 4-11. Geosafe Metal Stack Emissions Summary Data*
Analyte
Aluminum
Antimony
Arsenic
Barium
Beryllium
Cadmium
Calcium
Chromium
Cobalt
Copper
Iron
Lead
Magnesium
Manganese
Mercury
Molybdenum
Nickel
Potassium
Selenium
Silver
Sodium
Strontium
Thallium
Vanadium
zinc
Vapor
(H8/m3)
< 4.7
< 2.3
< 0.057
0.069
< 0.047
0.14
13
0.52
0.49
0.62
3.0
1.2
3.5
140
16
< 1.2
0.43
110
2.7
0.69
32
0.042
< 2.3
< 0.47
1.7
Phase**
(Ib/hr)
< 3.4E-05
< 1.7E-05
3.8E-07
4.9E-07
c 3.4E-07
1 .OE-06
9.3E-05
3.7E-06
3.5E-06
4.4E-06
2.2E-05
8.9E-06
1.9E-05
1 .OE-03
1.2E-04
< 8.5E-06
3. OE-06
8.1E-04
1.9E-05
4.9E-06
2.3E-04
3.0E-07
< 1.7E-05
< 3.4E-06
1.2E-05
Solid
(Hg/m3)
41
< 2.9
< 0.22
1.8
< 0.058
0.13
410
2.4
< 0.28
0.84
43
1.5
5.6
1.4
0.0046
5.5
1.1
18
4.7
< 0.29
73
0.74
< 2.9
< 0.57
5.7
Phase**
(Ib/hr)
2.9E-04
< 2.1E-05
< 1.6E-06
1.3E-05
< 4.2E-07
9.4E-07
2.9E-03
1.7E-05
< 2.0E-06
6.0E-06
3.1E-04
1 .OE-03
4.0E-05
9.9E-06
3.3E-08
3.9E-05
7.6E-06
1.3E-04
3JE-05
< 2.1E-06
5.2E-04
5.3E-06
< 2.1E-05
< 3.9E-06
4.0E-05
Total
(Hg/m3)
44
< 2.8
< 0.27
1.9
< 0.058
0.20
420
2.9
0.5 1
1.5
46
2.1
8.2
140
16
5.5
1.3
130
3.2
< 2.3
76
1.7
< 2.9
< 0.57
7.4
Metals**
(Ib/hr)
3. IE-04
< 2.0E-05
< 1.9E-06
1.3E-05
< 4.2E-07
1.5E-06
3 .OE-03
2.1E-05
3.6E-06
1 .OE-05
3.2E-04
1.5E-05
5.9E-05
1 .OE-03
1.2E-04
3.9E-05
9.5E-06
9.3E-04
2.2E-05
< 1.6E-05
5.4E-04
1.3E-05
< 2.1E-05
< 3.9E-06
5.3E-05
* - Complete data are presented in the Technology Evaluation Report.
** - Data reported are average values from three primary and one duplicate sample collected.
< - Analyte not detected at or above presented value (detection limit).
87
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non-detect were found on particulate filters. Arsenic was below reporting detection limits in all samples.
Chromium emissions were mostly in the particulate form, as were most of the remaining metal emissions.
It was not determined whether the chromium emissions were in the hexavalent or trivalent form. The
emission of lead was close to the detection limit in of the samples collected. Stack gas modeling
performed by the local regulatory agencies indicated that metal emissions were at levels that did not pose
a significant human health risk.
The hydrogen chloride emissions during the Demonstration were about 5.0 X 10" Ib/hr, well below the
4 Ib/hr performance standard of 40 CFR $264.343. This standard is established for an incinerator burning
hazardous waste. Although it may not be directly applicable, this standard does provide a background for
evaluating these emissions.
Particulate emissions averaged approximately 3.0 mg/m3. This value was not corrected for oxygen content
in the stack since supplemental oxygen was supplied to the thermal oxidizer. Even if the particulate
emissions were corrected, they would still be below the referenced performance standard for incineration
(see 40 CFR $264.343).
During the entire Demonstration, oxygen, carbon monoxide, and total hydrocarbons (as propane) were
monitored by Geosafe. The emissions of both total hydrocarbons and carbon monoxide were well within
the operational limits of the process and were each consistently below 10 ppmv throughout the
Demonstration
4.6.4 Limitations of the Data Results
The conclusions presented in this report have been based upon the information gathered during the
Demonstration. Great care was taken to ensure that the measurements collected were accurate and
representative. However, in some instances, engineering and analytical limitations restrict the use and
interpretation of some of these data. This section discusses some of these limitations.
After treatment, samples of the vitrified soil were collected from the surface of the treatment area. There
are some limitations associated with these samples. Although the vendor claims that the molten mass
becomes well-mixed by thermal gradients within the melt, a "cold cap" typically forms on the upper
-------
surface of the melt. Upon cooling, the upper surface of the melt may have been incorporated into the cold
cap and therefore is probably not representative of the center of the treatment area. It is highly likely that
all organic material within the test soil was destroyed by the intense heat generated during treatment.
Mercury and other metals may be found in higher concentrations at the center of the treatment area due
to a higher amount of vapor entrainment than that present at the melt surface. Additionally, the test soil
was covered with two feet of clean fill. It is possible that some of the post-treatment samples collected
may have been treated fill material. It should be noted that great care was taken to select samples that
represented the center of the treatment area. Large rock-like samples were collected from the melt
surface; the bottom portions of these samples were placed in containers for analysis. Given the volume
reduction upon treatment, it is highly probable that these samples were obtained from a depth that
contained contaminated soil. Future sampling is planned to obtain material closer to the center of the
treatment area after the soil has cooled. These samples will be used to verify the results presented in this
report. When obtained, the final results and conclusions of the Demonstration will be published in an
Addendum to this report.
Although the currently available data indicate that the technology was successful in achieving the Region
V cleanup criteria, it should be noted that some of the contaminants were already below the established
limits before treatment. This was especially true for chlordane which was not detected in any of the pre-
treatment soil samples collected during the SITE Demonstration. However, data collected by Region V
indicate that chlordane was present in the soil at the time the cells were filled (see Table 4-1). Mercury
levels were also below the target criteria before treatment. The data collected during this Demonstration
do indicate that substantial reductions occurred in contaminant concentrations after treatment.
The TCLP measurements were performed using standard SW-846 procedures. The method specifies that
the samples must be ground before leaching. This analytical procedure exposes a much greater teachable
surface area than would be present after actual remediation since practical applications of ISV create a
single large monolith. Therefore, the results of the TCLP analyses presented in this report most likely
represent a worst-case scenario. Actual teachability of a treated area is conservatively estimated to be as
good as or better than the results present in this report. The TCLP data presented for chlordane is
inconclusive because chlordane was not detected at or above its detection limit in the pre-treatment TCLP
samples
89
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Although dioxins and furans were known to be present in the test soil, they were not the primary focus
of this study because their concentrations in the soil were very low. The dioxin/furan results are limited
since only a few samples were collected from each matrix. The data collected suggest that the process
does not generate significant quantities of dioxins/furans during treatment.
Stack sampling activities concentrated on pesticide and metals emissions. Other stack samples were
performed at a limited frequency. It was not possible to collect stack samples throughout the entire ten-
day Demonstration. This would have been technically difficult and cost prohibitive. Therefore, the
samples collected represent emissions over a shorter time period than the average emissions throughout
the Demonstration. The investigators believe that these samples are representative of typical emissions
since sampling occurred while contaminated soil was being treated.
Volume reductions were calculated based upon density information gained from the surface samples. It
is possible that samples collected from the center of the treatment area may be more dense due to the
weight of the melt upon itself. During cooling, the material may form a more crystalline structure and
entrained gases (bubbles) may redissolve in the material during cooling. The volume reductions will be
confirmed during the future sampling event.
4.6.5 Process Operability and Performance at the Parsons Site
This section summarizes the operability of the process and the overall performance of the Geosafe ISV
system at the Parsons site. It includes discussions about developments and problems encountered, along
with the manner in which these items were resolved.
The in situ vitrification of the staged cells at Parsons improved with the progression of treatment.
Although the initial cells presented some treatment difficulties, during the Demonstration (treatment of
Cell 8), the system ran continuously for approximately ten days with only minor operational problems.
System operation was only interrupted for routine maintenance such as electrode segment addition and
adjustment. Throughout the remediation project, problems encountered were minor and limited to those
associated with the replacement of scrubber system heater cores (due to solids buildup), periodic
replacement of the hood panels, and final disassembly of the hood panels
90
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Originally, remediation of the nine cells at the Parsons site was scheduled to be completed in three
months. Treatment began in June 1993. Treatment time for the early cells exceeded the average treatment
time, as well as the expected treatment time. The amount of water that was present in the soil and close
proximity of shallow perched water contributed to longer treatment times in the early cells. Additionally,
unexpected lateral growth of the early melts increased treatment times when the original cell walls did
not effectively contain the treatment area. By early March 1994, Geosafe had completed five melts and
treated six cells. These five melts had unusually large overlap areas; the fourth and fifth melts extended
slightly into the Demonstration cell (Cell 8). Because of this overlap (and additional overlap in future
melts), the Parsons site was completely remediated in eight melts rather than nine (see Figure 4-5). In
late March and early April of 1994, the Demonstration was conducted on the sixth melt (Cell 8). All eight
melts were completed by June 1994, nine months after the original anticipated finish date. Data in the
economic analysis presented in this report is based on the planned treatment of nine melts in nine cells.
Geosafe did not meet the schedule for treatment at the Parsons site. This may be attributed to a number
of factors-some due to problems with the process, others due to constraints imposed by regulatory
agencies. EPA Region V and the Michigan Department of Natural Resources (MDNR) required Geosafe
to modify treatment procedures so that the emissions and odors from the stack were controlled. Because
the Parsons site is in a residential area, the offensive odor drew public attention. Further treatment was
halted until new permit conditions were established and process modifications were completed. The
technical requirements of an Air Quality Permit were specified by MDNR in a document entitled
"General and Special Conditions." Because Geosafe was required to comply with these conditions, this
document became a (Superfund site) ARAR for the State of Michigan. Verification of emissions rates
(including volatiles, semivolatiles, pesticides, dioxins/furans, metals, particulate matter, hydrogen
chloride, sulfur dioxide, carbon monoxide, nitrogen oxides, carbon monoxide, and total hydrocarbons)
was stipulated. All changes and modifications to the Geosafe equipment were required to be approved
by the EPA Region V. Because the system could not operate during this period, the permitting and
approval process added significantly to the time required to complete treatment.
Sulfur compounds in the scrubber liquor were suspected by Geosafe as the source of the odors. To
alleviate this problem, the scrubber water was changed at a higher frequency to reduce the amount of
sulfur compounds accumulating in the scrub solution. Additionally, Geosafe added a thermal oxidizer to
the end of the off-gas treatment system as a final treatment step prior to release of the gas stream to the
91
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IT 0 v, 0 v , E3 1
O : 0 ; C
•K' " "" * X- * - - A' v ^
r a -
0
Ik
y ' ~ ^
-------
shapes, limit emissions of vapor or steam, and restrict the melt energy inside the cell boundaries. Based
upon the experience Geosafe gained at Parsons, the design and construction of staged treatment cells will
be modified for future projects. It should be noted that the use of cobble in treatment cell construction
was unique to the Parsons site where the configuration and flow of the on-site groundwater dictated its
application.
During the treatment of Cell 2, a fire occurred as a result of a melt disruption. The fire was caused by
a rapid volatilization of 12-foot by 1-foot poly vinyl chloride (PVC) casing which had been left in the
treatment area to accommodate the previous electrode design. The PVC casing was empty and open at
the surface similar to an open-cased well. Four of these casings were located within each test cell.
Geosafe determined that the molten soil had contacted the PVC casing and melted a hole in it. This
allowed molten material to flow into the casing. The molten material immediately volatilized the PVC
casing and caused the expulsion of a small amount of molten material onto the surface soil within the
hood. This resulted in an excessive temperature rise on the hood surface and the subsequent burning of
combustible hood components. Although very smokey because of burning rubber materials, the fire was
small and did not cause the release of any hazardous materials or loss of off-gas containment. The fire
caused a disruption of Cell 2 treatment for over 100 hours while Geosafe repaired and replaced damaged
equipment. After the damaged equipment was replaced, the treatment of Cell 2 was continued. Geosafe
was successful in restarting and continuing the melt without the addition of a new starter path.
During the treatment of Cell 3 another small fire was encountered. This fire was caused by a molten area
that was exposed due to a collapsed portion of the cold cap. The radiant energy released was close to the
hood surface and caused excessive heating. The instrument lines leading to the electrode feeders began
to smolder and bum. This fire was quickly extinguished by Geosafe personnel and had little effect upon
treatment of Cell 3.
As a result of the fires, Geosafe removed all PVC casings from future melts and removed all combustible
materials from the hood. These corrective actions solved the fire-related problems, and no further
incidents of this nature were recorded during the treatment of the Parsons site.
Vitrification of some of the early cells at Parsons required considerably more time and power than
anticipated, and large amounts of scrubber water were generated. This was due in part to the high
93
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moisture content of the soil and the close proximity of shallow perched water. The perched water flowed
intermittently through a sand lens located eight to ten feet below the surface. Because of the large
amounts of water encountered during treatment of the early cells, Geosafe constructed an intercept system
to collect the perched water at the upgradient end of the treatment zone in a cobble wall. The collected
water ran under and beside the treatment zone in cobble and was then directed to two sump locations
from which it was pumped to a surface drainage ditch. The amount of water entering subsequent cells
was substantially reduced as a result of this action. A permit was obtained for discharge of water and
some liquid wastes generated during treatment after minor on-site treatment; however, all scrubber water
was collected and sent off-site for treatment and ultimate disposal, and therefore the on-site treatment
permit was not used.
Cells treated later in the remediation of the Parsons site required less energy than those treated in the
early stages of the project. Cell 8 was the sixth of eight melts performed at the Parsons site. Figure 4-6
graphically depicts the power input applied to Cell 8 during treatment. From this figure, it is apparent
that power levels were low during startup. Once the starter path melts enough of the surrounding soil,
power can gradually be increased. After the melt was established, power levels were maintained at
approximately 3 MW.
Some of the first few cells treated at the Parsons site did not achieve the desired treatment depth of
approximately 16 feet, possibly because of the accumulation of water at the bottom of the treatment areas.
This was observed during the first three melts, with melt three only reaching a depth of approximately
14 to 15 feet below land surface (BLS). During these initial melts, the rate of electrode penetration
slowed noticeably as the depth increased. Treatment of these cells was discontinued because further depth
progression could not be achieved in an economical manner. Large quantities of scrubber water were also
generated during these melts. During cell construction, thermocouples were strategically placed in the
treatment area to provide an indication of melt progress. Geosafe monitored temperatures indicated by
the thermocouples during treatment, and their data suggest that sufficient temperatures were achieved at
the bottom and comers of each setting such that, theoretically, mercury would volatilize and organic
contaminants would thermally decompose by pyrolysis. Since the contaminated soil was located at a depth
of 15 feet BLS, it is highly probable that all of the soil in these cells was vitrified or experienced
temperatures high enough to treat the soil. Depth objectives were met for all subsequent melt settings
after improvements were made to the groundwater intercept system.
-------
Power versus Time
I
-------
Electrode Depth Versus Time
18
16
14
* 12
~ 10
Electrode A1
* Electrode A2
Electrode Bl
• Electrode B2
0
03.22.94 0X24.94 03.2594 03.26% 03.27.94 03.28.94 03.30.94 03.3194 04.01.94
16:57 15:00 20:18 19:38 18:23 22:49 9:08 6:50 6:57
Tim*
Figure 4-7. Treatment Time Versus Electrode Depth During the Demonstration (Cell 8)
indefinitely. As each melt was completed, the surface was covered with several feet of clean fill soil. This
soil cover minimized emissions from the still-hot molten mass, and allowed equipment to travel over the
previously treated areas. After all of the melts were completed, the entire site was graded for future use
to be determined by the site owner. This is generally the disposal method that will be used for ISV,
especially when contaminated soils are treated without excavation and staging. If the material is not
removed from the ground, it cannot be subject to any RCRA land disposal restrictions. Additionally,
since there is a significant volume reduction from the original material, the layer of clean fill placed on
top can be deep enough to support grass or other ground cover without increasing the overall height of
the area.
At some sites, it may be desirable to remove the vitrified material. In this case, the monolith can be
excavated and removed by breaking it into pieces. Because of its immense size and weight, it is only
practical to remove the vitrified mass in pieces. Fracturing the mass may be aided by rapid cooling of
the molten material as described previously. The vitrified material can then disposed of elsewhere.
96
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The characteristics of the treated soil were found to meet the developer's expectations based on the
sampling of the treated soil surface. Visual inspection and physical analyses showed that the material was
hard, dense, and glassy. Leachability was insignificant for any target compounds (see Table 4-2 and 4-5).
Based on these characteristics, the material is believed to have a lifespan similar to natural obsidian, a
material known to last for'thousands to millions of years. Over the long term, it should be safe to place
this material in landfills or leave it in place at the site. Because this technology is still new and unproven
over the long term, this projection cam-tot be supported with any data at this time.
The ISV process generates a waste water stream during treatment. Some of the water removed from the
soil undergoing treatment may be reintroduced to the exhaust stream in the form of condensed humidity.
This occurs when lower operating temperatures are used in the off-gas treatment system or when the
amount of water removed from the soil exceeds the amount of water than can be passed through the off-
gas treatment system as humidity. When the soil undergoing treatment has a high moisture content, the
amount of water removed can be significant. During the Demonstration, the scrubber water generated
contained small quantities of the compounds previously identified; it was transported off-site for treatment
and ultimate disposal at a permitted facility. Decontamination liquid is produced at the conclusion of
treatment. Depending on contaminant levels, it is likely that this waste stream must be transported off-site
for disposal at a permitted facility. A third liquid stream generated at the Parsons site was diverted
groundwater. This waste stream was unique to the Parsons facility and was due to the close proximity
of shallow perched water. A discharge permit was obtained to carbon filter this water and discharge it
to a local drainage ditch.
The ISV system uses filters and activated carbon to remove particulates and vapors from the scrubber and
the gas stream. These materials may be recycled, however, when they are spent, they require disposal.
The filters and carbon can be treated in a subsequent ISV melt or they can be removed to an off-site
disposal facility. The amount of these materials generated is dependent on the soil characteristics
(moisture content, in particular) and the performance of the off-gas system
Miscellaneous wastes are also generated during treatment with ISV. These include used personal
protective gear (such as gloves and coveralls). These materials can sometimes be decontaminated and
disposed of as non-hazardous waste. Alternatively, they too can be placed in a new melt setting and
97
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treated with the waste. Miscellaneous waste generated from the last melt setting may need to be
containerized and disposed of as hazardous waste in an appropriate facility.
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SECTION 5
OTHER TECHNOLOGY REQUIREMENTS
5.1 Environmental Regulation Requirements
Federal, state, and local regulatory agencies may require permits before mobilization and operation of
the ISV technology. Most federal permits will be issued by the authorized state agency. Federal and state
requirements may include obtaining a hazardous waste treatment permit or modifying an existing permit.
Air emission permits may be required for any unit that could emit a hazardous substance. The Air Quality
Control Region may also have restrictions on the types of process units and fuels that would be used.
Local agencies may have permitting requirements for excavation, land treatment, and health and safety.
In addition, if waste water is disposed via the sanitary sewer, then the local water district would have
effluent limitations and sampling requirements, Finally, state or local regulatory agencies may also
establish cleanup standards for the remediation.
At the Parsons site, federal and state permits included a National Pollutant Discharge Elimination System
(NPDES) permit to discharge diverted groundwater to a nearby waterway. Air permits were acquired
from the state of Michigan. These permits specified changes in stack gas treatment monitoring that were
carried out before the Demonstration began. A thermal oxidizer was added to the treatment train to ensure
that permitting requirements were met. Sampling and monitoring was required for volatile organic
compounds, pesticides, mercury and other metals, total hydrocarbons, carbon monoxide, particulates,
sulfur dioxide, and nitrogen oxides. The requirements also specified the afterburner temperature,
calibration frequencies for continuous emission monitoring and discharge limits for components of the
stack gas
Local permits included various construction and operation permits from the Department of Building and
Safety, and permission to operate granted by the local Fire Department.
Transportation of the ISV process units across state lines requires permits; one of the trailers is
overweight. Current specifications for placarding, warning lights, and load limitations must be followed
during transportation of the system
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Personnel Issues
During treatment, the ISV system operated continuously. Three shifts of workers are required for
operation. Each shift has at least two people: a shift engineer and an operator. One site manager and one
project control specialist are also employed during the day shift to oversee operations. A rotating system
is used such that, each shift of workers is on-site for three continuous weeks. This is followed by one
week off, during which the workers may return home, if desired. A replacement shift of workers is sent
out each week to relieve the shift completing their three-week cycle.
Personnel operating the ISV technology must be trained in both the process operation and in health and
safety practices associated with hazardous material. Each worker must have completed the OSHA-
mandated 40-hour training course for hazardous waste work, and have an up-to-date refresher
certification. At least one member of each shift team must be certified in CPR and First Aid, and
additional high voltage training is required. Personnel must be enrolled in a medical monitoring program
to ensure that they are fit to perform their job duties and to detect any symptoms of exposure to
hazardous materials
Community Acceptance
A Visitor's Day meeting was held in March 1994 to distribute information to the public on the
remediation project and on the SITE Demonstration of the ISV technology. The meeting included
presentations by Geosafe and the EPA SITE project manager, along with a brief tour of the site and
technology. Participants in the Visitor's Day included regulatory personnel, remediation contractors, and
members of the local public. The turnout at the Visitor's Day was high, indicating strong interest in the
ISV technology and its application for remediation at Parsons and similar sites.
The ISV technology can operate on soils in situ, reducing the need for excavation, and the accompanying
noise, traffic, and dust generation. Treatment of a small area can be completed rapidly if no technical or
regulatory delays are encountered. After backfilling the subsidence with clean soil, the site can be
landscaped or converted for another beneficial use. ISV remediation at the Parsons site was conducted
near inhabited areas; a church and residences were located within a few hundred feet of the treatment
100
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5.2 Personnel Issues
During treatment, the ISV system operated continuously. Three shifts of workers are required for
operation. Each shift has at least two people: a shift engineer and an operator. One site manager and one
project control specialist are also employed during the day shift to oversee operations. A rotating system
is used such that, each shift of workers is on-site for three continuous weeks. This is followed by one
week off, during which the workers may return home, if desired. A replacement shift of workers is sent
out each week to relieve the shift completing their three-week cycle.
Personnel operating the ISV technology must be trained in both the process operation and in health and
safety practices associated with hazardous material. Each worker must have completed the OSHA-
mandated 40-hour training course for hazardous waste work, and have an up-to-date refresher
certification. At least one member of each shift team must be certified in CPR and First Aid, and
additional high voltage training is required. Personnel must be enrolled in a medical monitoring program
to ensure that they are fit to perform their job duties and to detect any symptoms of exposure to
hazardous materials.
5.3 Community Acceptance
A Visitor's Day meeting was held in March 1994 to distribute information to the public on the
remediation project and on the SITE Demonstration of the ISV technology. The meeting included
presentations by Geosafe and the EPA SITE project manager, along with a brief tour of the site and
technology. Participants in the Visitor's Day included regulatory personnel, remediation contractors, and
members of the local public. The turnout at the Visitor's Day was high, indicating strong interest in the
ISV technology and its application for remediation at Parsons and similar sites.
The ISV technology can operate on soils in situ, reducing the need for excavation, and the accompanying
noise, traffic, and dust generation. Treatment of a small area can be completed rapidly if no technical or
regulatory delays are encountered. After backfilling the subsidence with clean soil, the site can be
landscaped or converted for another beneficial use. ISV remediation at the Parsons site was conducted
near inhabited areas: a church and residences were located within a few hundred feet of the treatment
100
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area. Other than during mobilization and demobilization activities, the treatment neighborhood did not
experience any significant increase in traffic at the site dut; to the remediation activities,
There are potential inconveniences associated with treatment operations. The hood to cover the treatment
melt is large, lighted, and therefore conspicuous. Since operation must occur continuously once a melt
has staled, lights and noise will be present at all hours, This may not be acceptable in residential areas.
boring the first melt, porous pathways in the cobble walls of the treatment cells caused minor problems
adjacent to the site. Odors from the operation were also a source of public complaint. During the second
melt, a fire occurred which required the response of the local fire department and attracted public
attention to the site, Construction and operational changes were made during treatment so that these
problems were no longer occurring at the time of the SITE Demonstration, These solutions will be
implemented at subsequent treatment operations, thus reducing the potential for recurrence. The ISV
process consumes a great deal of electrical dower" During the treatability phase of ISV application, the
electrical infrastructure should be examined and augmented as necessary to avoiid any negative impact on
the community
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Prior to the SITE Demonstration, EPA Region V had already performed sampling events on the Geosafe
system to evaluate the cleanup effort at the Parsons site. Data were also gathered in response to odor
complaints and problems identified during the first five melts prior to the Demonstration. These data were
provided to the SITE investigators, and this information was used to refine sampling strategies used
during the Demonstration. This section presents some of the Region V data and discusses some
conclusions which are suggested from the interpretation of these data.
On December 1 and 2, 1993, Region V conducted stack sampling both before and after the off-gas
treatment system to evaluate its effectiveness. At that time, the Geosafe system was fully operational and
was performing the fourth melt at the Parsons site. The inlet data represents samples collected from the
piping connecting the off-gas hood to the off-gas treatment system. A special section of piping was
constructed to facilitate stack sampling at this location. The thermal oxidizer had not been added to the
off-gas system prior to this sampling event, so the outlet data represents the exhaust to the atmosphere
immediately after the blower. Subsequent modifications to the off-gas treatment system, including the
installation of the thermal oxidizer, were made to improve system performance in cleanup of gaseous
emissions. The sampling indicated that the VOC levels at the stack were below state ARAR values.
Table 6-1 presents volatile organic compound emissions for the two sampling days at both the inlet and
outlet of the off-gas treatment system. Approximately five samples were taken per day from these
locations; the values presented are the averages of those results. The data indicate that there is some
variation in the emissions generated during treatment. In some cases (Day Two), the data indicate that
some of the volatiles were removed from the air stream by the off-gas treatment system. However, the
Day One data suggest that the treatment train did not reduce these compounds. This is not surprising
since the treatment system was not specifically designed to treat volatile organic emissions. Although
activated carbon was part of the treatment train, the data suggest that it was ineffective in eliminating
volatile organic emissions
Presented in Table 6-2 is the semivolatile organic compounds emission summary data. The data suggest
that the off-gas treatment system is effective in treating semivolatile organic compounds as all
concentrations detected at the inlet were reduced at the outlet sampling location. Most concentrations were
reduced by two to three orders of magnitude
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Table 6-1. Region V Geosafe Stack Volatile Organic Compound Emissions Summary Data
VOST Emissions
Acetone
Benzene
Bromomethane (Methyl Bromide)
2-Butanone (MEK)
Carbon Disulfide
Chloromethane (Methyl Chloride)
Ethylbenzene
Methylene Chloride
4-Methyl-2-Pentanone (MIBK)
Styrene
Toluene
Vinyl Chlonde
Xylenes (Total)
Inlet
(ppmv)
2.6
0.92
0.076
0.29
0.069
0.55
0.014
1.3
0.0012
0.014
0.12
0.0031
0.00050
Dayl
outlet
(ppmv)
1.9
1.3
0.0060
0.35
0.12
0.51
0.26
1.4
0.11
0.11
0.34
0.0040
0.45
Day 2
Inlet
(ppmv)
3.4
14
0.045
2.0
0.27
0.60
0.94
8.0
0.64
0.44
6.3
1.6
1.5
outlet
(pprmA
3.4
7.5
0.034
1.0
0.18
0.57
0.20
2.9
0.29
0.33
4.0
0.55
0.30
<- Compound not detected at or above presented value (detection limit).
Metals stack emission summary data is presented in Table 6-3. As with semivolatile compounds, all metal
concentrations were significantly reduced after being treated by the off-gas treatment system. Specifically,
mercury concentrations were reduced by slightly more than three orders of magnitude to indicate the
effectiveness of the off-gas treatment system on metals
At the time these samples were collected, Region V monitored the stack gases using continuous emission
monitors (CEMs) to evaluate the concentrations of carbon monoxide, carbon dioxide, nitrogen oxides,
sulfur oxides, and total hydrocarbons. Typical results are presented in Table 6-4. As noted, the gas
treatment system was effective in removing the nitrogen and sulfur oxide emissions. The carbon monoxide
emissions ranged between 33 and 53 Ib/hr which was significantly below the state ARAR level of 638
Ib/hr. The total hydrocarbon data verified the organic stack emission data, confirming that organics were
not being completely removed by the off-gas treatment system.
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Table 6-2. Region V Geosafe Stack Semivolatile Organic Compound Emissions Summary Data
Semivolatile Organic Emissions
Acenaphthene
Acenaphthylene
Anthracene
Chrysene
Dibenzofuran
Di-n-butylphthalate
2,4-Dimethylphenol
Fluoranthene
Fluorene
2-Methylnaphthalene
2-Methylphenol
4-Methylphenol
Naphthalene
2-Nitrophenol
Phenanthrene
Phenol
Pyrene
Day 1
Inlet Outlet
(romv) tromv)
0.010 < 4.2E-04
0.0080 < 4.3E-04
0.010 < 3.6E-04
0.0030 < 2.8E-04
0.059 < 3.8E-04
0.0070 4.0E-04
0.075 < 5.3E-04
0.015 1.6E-05
0.038 < 3.9E-04
0.17 2.7E-05
0.35 < 6.0E-04
0.55 < 6.0E-04
0.49 1.1E-03
0.010 < 4.7E-04
0.087 7.3E-05
2.0 2.9E-03
0.010 < 3.2E-04
Inlet
(ppmv)
0.014
0.0080
0.013
0.0030
0.071
0.0050
0.07 1
0.022
0.048
0.18
0.28
0.59
0.51
0.019
0.12
2.1
0.013
Day 2
Outlet
(ppmv)
. < 4.2E-04
< 4.3E-04
< 3.7E-04
< 2.9E-04
< 3.9E-04
< 2.3E-04
< 5.3E-04
< 3.2E-04
< 3.9E-04
< 4.6E-04
1.8E-04
2.4E-04
<5.1E-04
< 4.7E-04
< 3.7E-04
4.2E-03
< 3.2E-04
< - Compound not detected at or above presented value (detection limit).
Table 6-3. Region V Geosafe Stack
Metals Emissions
Arsenic
Chromium
Lead
Mercury
Metals Emissions Summary Data
Day 1
Inlet Outlet
(Ib/dscf) (Ib/dscf)
5.2E-05 < 3.6E-08
1.6E-06 2.8E-07
7.2E-05 2.2E-06
4.1E-06 1.3E-09
Day 2
Inlet
(Ib/dscf)
1.1E-04
5.5E-06
7.3E-05
5.5E-06
Outlet
(Ib/dscf)
< 3.6E-08
5.4E-07
5.2E-07
3.4E-09
: - Metal not detected at or above presented value (detection limit).
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Table 6-4. Region V Geosafe Typical CEM Emissions
Analyte Emission Rate (Ib/hr)
Carbon Monoxide 43
Nitrogen Oxides 0.21
Total Hydrocarbons 3.0
Sulfur Oxides 0.050
Part of the investigation into the process emissions included sampling a portion of one of the used high
efficiency particulate air (HEPA) filters. The HEPA filter was analyzed for semivolatile organics,
pesticides, dioxins/furans, metals, and sulfur. The results are summarized in Table 6-5. As noted in the A,
table, high levels of arsenic (1,700 mg/kg), lead (1,600 mg/kg) and mercury (1,200 mg/kg) were ^
detected. Chromium was also present at 57 mg/kg. All other detectable target organic compounds were
present at moderately low levels. The metals arsenic, lead, and mercury can be classified as somewhat
volatile, and therefore their detection in the particulate form on the HEPA filters is not surprising.
Chromium may have come from the melt and from deterioration of the hood panels and other parts of
the stainless steel off-gas treatment system since this metal is relatively non-volatile. The results presented
in Table 6-5 indicate that the filters performed very well.
Region V also performed various analyses pertaining to the off-gas hood itself. These tests included an
interior wipe of the hood after treatment of a cell, and analysis of deposits of the off-gas hood wall itself.
By wiping the interior of the off-gas hood and analyzing the residue, Region V hoped to gain insight
about equipment contamination and contamination buildup during operation. An analysis of the Region
V samples for semivolatile organic compounds and pesticides yielded concentration values below the
detection limits for the wipe residue. Mercury was detected in the wipe sample.
When moving the hood at the completion of a melt, flaky deposits from the interior of the hood fell off
and were deposited on top of the clean soil surrounding the treated area. Analysis of these deposits
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Table 6-5. Region V Geosafe HEPA Filter Analysis
Analysis
Units
Result
Total Solids
% Solids
92
Metals
Arsenic
Chromium
Lead
Mercury
Semivolatile Organics
Benzo(a)anthracene
Benzo(b)fluoranthene
Benzo(g,h,i)perylene
Bis(2ethylhexyl)phthalate
Butyl benzyl phthalate
Chrysene
Fluoranthene
Phenanthrene
Pyrene
Organochlorine Pesticides and PCBs
4,4'-DDE
Polychlorinated Dioxins
HxCDDs (total)
HpCDDs (total)
l,2,3,4,6,7,8_HpCDD
OCDD
m&g
mg/kg
mg/kg
Hg/kg
^g/kg
Hg/kg
Hg/kg
Hg/kg
1,700
57
1,600 J
1,200
220
380
160
500
150
300
230
270
370
22
0.41
0.78
0.33
0.83
J - Value reported is less than the reporting detection limit but greater than the method detection limit.
Value is an estimate.
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showed metals concentrations at the levels presented in Table 6-6. Region V expressed concern over the
chips since they flaked easily from the interior surface of the hood during movement. The problem was
easily remedied by using a vacuum to remove the deposits from the ground surface and the hood interior
panel surfaces. The flakes and associated dust were placed into subsequent melt settings for treatment.
After treatment was completed at Parsons, the hood panels were disposed of as secondary waste since the
cost of decontamination activities would have exceeded the value of the panels. Because the hood panel
corrosion at the Parsons site was much more rapid than anticipated, Geosafe investigated the situation and
found that high levels of sulfur at the site resulted in unexpected and increased rates of corrosion. In
addition, Geosafe determined that the long periods of inactivity experienced between the first few melts
resulted in exposure to moisture conditions that enhanced corrosion. When the corrosion rate was noted
to be of concern, Geosafe initiated "coupon" testing directed at identifying alternative materials for
improved hood panel performance. The coupon testing at the Parsons site has identified hood materials
that are currently being testing as part of full-scale treatment at another site.
Region V also performed a limited number of analyses on treated soil obtained from melts completed
prior to the SITE Demonstration. Some of these samples were analyzed using neutron activation analysis.
This is a non-intrusive procedure that can eliminate interferences and recovery bias associated with
standard sample digestion procedures for metals. In this procedure, neutrons produced during nuclear
fission are used to activate a sample to form radioactive isotopes. As these isotopes decay, the energy is
quantized and related to a particular element. By counting the disintegrations per unit of time, a
statistically valid concentration of elemental abundances can be determined. There were no published EPA
methods pertaining to this procedure at the time of testing, and therefore this procedure was not used
during the Dimonstration. Results of the Region V treated soil metal data are presented in Table 6-7.
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Table 6-7. Region V Geosafe Neutron Activation Analysis on Treated Soil
Metal Concentration (mg/kg)
Arsenic 2.3
chromium 48
Mercury < 5.0
Region V conducted an excavation of the first melt to determine the extent of treatment and to evaluate
if migration of site contaminants into adjacent clean soil had occurred as a result of treatment. The
samples collected during this excavation were analyzed for volatile organics, semivolatile organics,
dioxins/furans, pesticides, and metals. The results of these data are presented in Table 6-8. There were
no semivolatile or dioxin/furans detected in these samples. All Region V target analytes were well below
the cleanup criteria. Traces of the pesticides were detected. Because pre-treatment sampling was not
conducted outside the treatment area, the source of these pesticides is unknown. It may stem from existing
contamination from previous chemical activities at the Parsons site or migration from other contaminated
area of the site via rainwater runoff. It is inappropriate to assume that these low levels of pesticides were
a result of ISV treatment. In most instances, the concentrations detected are considered insignificant.
Current information regarding the status of Geosafe's commercial activities have been provided by the
vendor and is presented below. After completion of vitrification operations at the Parsons site, Geosafe
mobilized its equipment to a General Electric Company site in Spokane, Washington for performance of
a TSCA demonstration project in support of an application for a National TSCA Operating Permit. The
GE/TSCA demonstration involved treatment of 3,500 tons of soil contaminated with polychlorinated
biphenyls (PCBs) to a maximum level of 17,000 mg/kg. The soil was staged in five treatment cells to
a depth of 15 feet. In addition to the contaminated soil, the treatment volume contained approximately
80 unsealed steel drums and significant quantities of asphalt and concrete debris.
The TSCA demonstration project was performed under a permit issued by EPA's TSCA authorities. EPA
personnel witnessed critical melting operations and participated in the acquisition, analysis, and evaluation
of performance data. The five melts were performed without difficulty, and Geosafe was able to complete
the project on schedule. Preliminary off-gas treatment data indicated that the level of PCBs in the stack
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outlet was less than the detectable limit. The ISV equipment operated without difficulty during the
complete project. Geosafe was able to make further improvements in operations efficiency and reduced
hood movement time to less than two days. Geosafe expects to receive a National TSCA Operating Permit
for treatment of PCBs at the conclusion of EPA's evaluation process.
Geosafe completed the GE/TSCA project in early October 1994. The ISV equipment was then mobilized
to the Wasatch Chemical Superfund Site in Salt Lake City, Utah where it is being used to treat
approximately 7,000 tons of soil and debris contaminated with dioxins, pentachlorophenol, several
pesticides, and other organics. Vitrification operations began at the Wasatch site late in 1994.
6.2 Scaling Capabilities
Geosafe has stated that ISV can be used to treat contaminated soil in situ in several configurations. They
have proposed to treat soils that are deeper than the 20-foot maximum depth of a single ISV melt in
stages. There are two approaches. The shallower intervals can be treated initially, and the vitrified
product can be removed, allowing the deeper intervals to then be treated. Alternately, the top layers of
soil can be removed and stored separately until the deeper soils are vitrified. The soils can then be
replaced and vitrified on top of the first set of melts. Due to the volume reduction, additional soil from
other areas can be added in the same space. These methods have not been fully demonstrated, however
future activities are planned.
Geosafe's existing full-scale equipment is the largest ISV equipment that has been developed. A single
system is in existence. Battelle Memorial Institute has studied larger units for the U.S. Department of
Energy and has determined that significantly larger ISV systems can be designed and fabricated. To date,
this has not been performed.
In the future, more than one full-scale ISV system may be used to expedite treatment of large sites in an
economic fashion. Cost savings may also be incurred by the use of an ISV system two to three times
larger than the current 4 MW system. A larger system would not only have a higher throughput rate and
lower operating cost, but would also be able to produce larger melts and process to greater depths.
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Table 6-8. Region V Geosafe Melt 1 Excavation Soil Analysis
Metals
Analyte
Arsenic
Lead
Mercury
Organochlorine Pesticides
Analyte
B-BHC
G-BHC
4,4 '-ODD
4,4 '-DDE
4,4 '-DDT
Dieldrin
Endrin
Heptachlor
Heptachlor epoxide
Volatile Organics
Analyte
Benzene
2-Butanone (MEK)
Methylene chloride
Toluene
Xylenes
Sample 1
Concentration
(me/kg)
4.1
7.4
< 0.050
Sample 1
Concentration
(Hg/kg)
3.4
2.7
< 3.3
9.2
< 3.3
2.7
3.6
1.8
3.2
Sample 1
Concentration
(Hg/kg)
4.0
< 10
49
3.0
1.0
Sample 2
Concentration
(me/ke)
3.4
5.0
0.12
Sample 2
Concentration
(Hg/kg)
2.7
1.7
7.9
13
9.6
3.6
< 3.3
< 1.7
< 1.7
Sample 2
Concentration
(Hg/kg)
< 4.0
16
11
1.0
< 1.0
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REFERENCES
1 U.S. Environmental Protection Agency. 1993. Innovative Treatment Technologies: Annual Status
Report; Fifth Edition. EPA 542-R-93-003. U.S. Environmental Protection Agency. Office
of Solid Waste and Emergency Recovery. Washington, D.C.
2 Hansen, J.E. 1993. "In Situ Vitrification (ISV) for Remediation of Contaminated Soil Sites.
Geosafe Corporation. Richland, Washington.
3 Timmons, D.M., V. Fitzpatrick, and S. Liikala. 1990. "Vitrification Tested on Hazardous
Wastes." Pollution Engineering, June 1990. pp. 76-81.
4 U.S. Environmental Protection Agency. 1992. Handbook on Vitrification Technologies for
Treatment of Hazardous and Radioactive Waste. EPA/6225/R-92/002. U.S.
Environmental Protection Agency. Office of Research and Development. Washington
D.C.
5 Douglas, J.M. Conceptual Design of Chemical Processes; McGraw-Hill, Inc. New York, 1988
6 Peters, M.S. ; Timmerhaus, K. D. Plant Design and Economics for Chemical Engineers; Third
Edition. McGraw-Hill, Inc. New York, 1980.
7 Garrett, D.E. Chemical Engineering Economics; Van Nostrand Reinhold, New York, 1989.
8. Liikala, S.C. 1991. "Applications of In Situ Vitrification to PCB-Contaminated Soil." Presented
at the 3rd International Conference for the Remediation of PCB Contamination, Houston,
Texas, March 25-26, 1991.
9 U.S. Environmental Protection Agency. 1986. Test Methodsfor Evaluating Solid Waste. SW-846.
U.S. Environmental Protection Agency. Office of Solid Waste. Washington D.C.
10. Geosafe Corporation. 1992. "Whole Rock Analysis." In Situ Vitrification Technology Update
Geosafe Corporation. Richland, Washington.
11 Timmons, D.M. and V. Fitzpatrick. 1990. "In Situ Vitrification: Heat and Immobilization are
Combined for Soil Remediation." Hazmut World, December 1989.
12 Dragun, J. 1991. "Geochemistry and Soil Chemistry Reactions Occurring During In Situ
Vitrification." J. Hazardous Materials, 1991. pp.343-363.
13 Science Applications International Corporation. 1993. "Geosafe In Situ Vitrification
Demonstration Plan." Science Applications International Corporation. Process
Technology Division. San Diego, California
14 Office of Federal Register. 1993. Code of Federal Regulations Title 40, Protection of
Environment. U.S. Government Printing Office, Washington, D.C. July 1993.
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APPENDIX A
VENDOR'S CLAIMS
This appendix presents the claims made by the vendor, Geosafe Corporation, regarding In Situ Vitrifi-
cation (ISV), the technology under consideration. This appendix was written solely by Geosafe, and the
statements presented herein represent the vendor's point of view based on over 190 tests,
demonstrations, and commercial melts performed since 1980. Publication here does not indicate EPA's
approval or endorsement of the statements made in this section; EPA's point of view is discussed in the
body of this report
A.I Summary
Geosafe considers that the SITE demonstration performed at the Parsons Chemical site was very
successful. Geosafe believes that the SITE demonstration, together with the other seven melt settings
of the Parsons project, over 190 other tests and demonstrations of the technology, and large-scale
remediation work that has been performed since the demonstration, have clearly shown the efficacy of
the ISV technology for treatment of contaminated soil sites. The technology has been shown effective
for the treatment of soil and other earthen materials contaminated with a broad range of organic,
inorganic, and radioactive materials. This Vendor Claims section summarizes the capabilities of the ISV
process that have been developed to date; it also comments on the results of the Parsons Project and the
SITE demonstration performed there.
The ISV technology is a unique on-site and in situ thermal treatment technology with specific advantages
relative to alternative technologies, including:
o ability to simultaneously process mixtures of all contaminant types
• ability to attain high destruction, removal, and/or immobilization treatment effectiveness
• production of a vitrified residual product with unequalled chemical, physical, and
weathering properties
• maximum permanence of treatment, including geologic life expectancy of the vitrified
product
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• maximum volume reduction
• good public acceptance related to on-site and in situ safety benefits and quality of
treatment and residual vitrified product
• cost effectiveness that increases with increasing site difficulty and stringency of cleanup
standards.
Numerous application configurations are available to allow application of ISV to a wide range of site
conditions. The equipment system has been demonstrated to be highly reliable, and to be adaptable to
specific site needs. There are few site conditions that cannot be handled by adaptation of the site and/or
the process and equipment. The process is now available for contaminated soil site remediation on a
large-scale commercial basis. The process continues to be developed for buried wastes and other
advanced applications.
The Parsons Site Project was Geosafe's first large-scale remediation project performed on a commercial
basis. The site presented several challenges that had not been previously experienced during large-scale
ISV operations. It was necessary for Geosafe to make several adaptations to the technology, which
allowed successful demonstration both of the technology's and Geosafe's ability to adapt to site-specific
challenges
The SITE demonstration was performed on the sixth of eight melts performed during the Parsons
Project. Demonstration results confirmed the capabilities of the ISV technology where relevant site
conditions existed. The demonstration confirmed that all performance criteria for the site were met.
A.2 Introduction
The ISV process involves electric melting of soil and other earthen materials for purposes of removing,
destroying, and/or permanently immobilizing hazardous and radioactive contaminants. The patented
process was originally developed by Battelle Memorial institute for the U.S. Department of Energy
(DOE), with the intent of possibly treating transuranic-contaminated soils in situ at DOE sites.
Developmental testing of the process proved it to be highly effective for a broad range of hazardous and
radioactive contaminant types, earthen media types, and application configurations.
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The ISV process, which has been described in more detail elsewhere in this report, involves the melting
of a solid media. It is the molten media that conducts the electricity, and converts it to heat (joule
heating). The high melt temperature results in removal and/or destruction of organic and other
vaporizable contaminants. Immobilization of heavy metals, whether radioactive or non-radioactive,
occurs as the heavy metals are incorporated into the residual vitrified product that forms upon cooling
of the melt. Because of these simultaneous removal, destruction, and immobilization treatment
mechanisms, EPA has variously classified ISV as a thermal treatment, a solidification/stabilization treat-
ment , and a physical/chemical treatment process.
A. 3 Applicability to Contaminated Soil and Other Earth-Like Materials
ISV may be applied to any media that is capable of forming and supporting a joule-heated melt. Such
materials include most natural soils, sediments, mill tailings, and other earthen materials. These
materials consist predominantly of metal oxides (e.g., Si02, A1203, F^C^) that have adequate electrical
conductivity in the molten state and will produce a vitrified product upon cooling. In relatively
infrequent cases, some natural earthen materials do not contain adequate alkali materials to provide the
desired molten state electrical conductivity. In such cases, fluxant materials may be added to obtain the
desired melt properties.. In similar manner, some natural earthen materials, e.g., limestone, may not
produce the desired vitrified product properties upon cooling. In such cases, typical silicate type soils
may be added to produce a good quality vitrified product.
Because of these features, ISV is most often applied to contaminated earthen materials. It may also be
applied to various non-soil waste materials (e.g., process sludges, incinerator ash) by combining them
with earthen media for treatment. For example, non-soil sludges may be processed by intermixing with
soil for treatment, or by forming a melt in soil placed above the sludge and allowing it to melt down
through the sludge. Waste lagoons and evaporation ponds may be treated in this manner
In some cases, the waste material itself may be analogous to earthen materials and be processed without
modification. Municipal incinerator and coal power plant ashes are examples of such materials; their
origin lies in other earthen materials (e.g., coal, metal ores), and they possess essentially the same
chemical composition as earthen materials.
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Application Configurations
ISV is applied to contaminated media in place where it presently exists (termed in situ melting), as
opposed to bringing the media to, and feeding it into, the melting equipment (termed ex situ melting).
The materials subject to ISV may be undisturbed soil deposits that have inadvertently become
contaminated, or they may be earthen materials that have become contaminated through some
engineered waste treatment and/or disposal process (e.g., buried/landfilled waste, sludge lagoons and
evaporation ponds). In many cases, ISV may be applied to these materials where they presently exist;
alternatively, the configuration of the materials may be changed if desired to allow more efficient or
cost-effective ISV treatment. For example, soils from a shallow evaporation pond may be reconfigured
(staged) to a greater depth to allow for more economic ISV treatment. Figure A-l illustrates some of
the reconfiguration options that allow ISV application to most situations involving contaminated earthen
materials.
A.5 Contaminant Treatment Effectiveness and Permanence
Organics are completely removed from the media volume melted due to their inability to exist within
the typical soil melt temperature range of 2,900 to 3,600°F (1,600 to 2,000°C). During ISV, organic
contaminants are vaporized by heat from the thermal gradient present in front of the melt. Upon
vaporization, the organics move toward the ground surface, either through the melt or very closely
adjacent to it. The specific soil gas-phase permeability has a direct bearing on the pathway of gases and
vapors to the surface.
Several options exist for the final treatment of the organic vapors, including: 1) destruction by pyrolytic
thermal decomposition below grade, 2) oxidation upon contacting air at the ground surface, and/or 3)
entry into the off-gas volume followed by removal and/or thermal destruction during off-gas treatment.
Typically, substantially all of the organics are destroyed during ISV processing, with the possibility of
very small amounts becoming part of the off-gases which are subsequently removed or destroyed by the
off-gas treatment system
Heavy metals are predominantly immobilized by ISV processing to the extent of their solubility in the
molten media. The immobilization mechanisms are chemical and physical incorporation into the vitrified
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IN SfTU VITRIFICATION
Configuration Alternatives
In Situ
Contaminated Soil
In Situ
Staged In Situ
Stationary/
Batch
Intermittent
Molten Material
Removal
Intermittent
Materiel
Feeding
Stacked
Upper Melt Done
Lower Melt Done After Replacement
After Excavation & tuctnt^ Material
(1)
(2)
Layered
Upper Material
Treated
Upper Material
Removed After
Treatment
Lower Material
Treated
Figure A-l. Various Configuration Options for ISV Processing
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product. The retention efficiency (i.e., percentage entering the melt as opposed to volatilizing to the off-
gases) is a function of many variables which can be analyzed in advance of treatment to determine
expected performance. Most priority pollutant metals, including semivolatiles like lead and arsenic, are
retained at very high levels, with the remainder being subject to removal during off-gas treatment. At
the other extreme, ISV is a removal process for mercury due to its high vapor pressure and low
solubility in typical silicate melts. The quality of heavy metal immobilization within the vitrified
product, as measured by TCLP testing, is unequalled compared to other immobilization/stabiliza-
tion/solidification technologies.
Radioactive materials of interest are typically heavy metals (e.g., plutonium, uranium, cesium,
strontium) and are immobilized like heavy metals during ISV as described above. ISV may also be
employed to prevent radon release to the environment (air pathway). Radon, a gas that is formed by
decay of radium within a vitrified material, is contained by the material until such time that it decays
further, back to a solid. Several orders of magnitude reduction in the radon emanation rate can be
achieved.
A. 6 Residual Vitrified Product
ISV treatment of natural earthen materials results in a single, large, monolithic, rock-like mass that is
predominantly vitreous (glassy) in nature. Some amount of microcrystallinity may exist within the
vitrified mass depending on the mixture of metal oxides that were melted together and the cooling time
experienced. Vitrified product from natural soil melts possesses the following characteristics: 1) it is
typically about 10X the strength of unreinforced concrete in both tension and compression, 2) it is
unaffected by wet/dry and/or freeze/thaw cycling, 3) it has acceptable biotoxicity (i.e., not toxic to near-
surface life forms), 4) it is unequalled compared to other treatment products in its ability to withstand
weathering for a geologic time period.
Conversion of treated media into a vitrified product results in a large volume reduction (e.g., 25 to 50%
for most natural soils). The volume reduction results from removal of void volume present between
solid particles, the removal of vaporizable materials present, and the thermal decomposition of some
mineral materials (e.g., limestone will calcine to lime while giving off COJ. Volume reductions on the
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order of 70 to 80% or more are achievable for certain sludges and buried wastes. The resulting density
of vitrified product from soil melts is typically in the range of 2.5 to 2.8 g/cc.
Because the vitrified material contains zero organics, and it securely immobilizes the heavy metals
present, the vitrified material is no longer hazardous and should be suitable for "delisted" regulatory
status. Given such status, the vitrified monolith should be suitable for leaving on-site, and the land
should be available for other uses without restriction.
A. 7 Air Emissions and Other ARARs
The existing ISV off-gas treatment system design has been demonstrated capable of meeting air emission
standards for the states of Washington, Michigan, and Tennessee (see results for Parsons Project in later
section). It is important to note that the system can be modified if necessary to meet specific state stan-
dards. Geosafe is not aware of any state or federal air emissions standards that would preclude its use
within the U.S.
In similar manner, Geosafe is not aware of any other state or federal ARARs that would prohibit the
use of ISV compared to other alternative technologies. The technology is quite flexible regarding
application configurations, and the remedial design can be adapted as necessary to comply with typical
ARARs.
A. 8 Application Limitations
ISV is subject to eight (8) basic types of limitations as defined below
A.8.1 Media Melting Characteristics
The contaminated media must be suitable for melting within the operating capabilities of the equipment
system. This suitability for melting relates primarily to the geochemical composition of the media,
which determines melting properties (e.g., melt temperature, viscosity) and molten state electrical
conductivity. Most natural soils can be efficiently melted by ISV without any modification. In relatively
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rare cases (e.g., highly leached soils), the addition of alkali materials may be desirable to increase melt
electrical conductivity and to lower melting temperature or melt viscosity.
Vitrified Product Quality
The media composition and melt cooling rates are the primary determinants of vitrified product quality.
Most natural soils and other earthen materials possess sufficient glass forming minerals (e.g., silica,
alumina) to produce an excellent residual product. Note that it is a common misconception that sandy
soil is required to obtain a vitreous product. In fact, most soil types (e.g., gravel, sand, clay, silt)
possess glass forming materials in abundance. Limestone and dolomite soils are possible exceptions to
this. Whereas these soil types typically contain some amount of silica, they may require some addition
of good glass forming soil to produce the desired quality of vitrified product.
The ISV process typically produces a higher quality vitrified product than do other vitrification
technologies because ISV can be operated at a higher temperature than melter- or furnace-based
technologies. Because glass at high temperatures can corrode the refractory linings of ex situ melters,
furnaces, kilns, and similar devices, fluxants are added in such applications to lower the melting
temperature, which also results in some diminishing of vitrified product quality. Such "fluxing down"
is not required in ISV since there is no refractory lining to be concerned about. Therefore, the higher
melting temperature of ISV produces the highest possible vitrified product quality.
A high quality vitrified product is necessary if heavy metals immobilization is a desired objective. If
ISV is employed only to destroy/remove organic contaminants, then the vitrified product quality is not
important because no organics continue to exist within the vitrified mass
A.8.3 Water Recharge
ISV may be applied to fully saturated, even supersaturated, media. This is possible because the thermal
gradient in front of the advancing melt simply dries the wet media out before melting it. Water can be
a limitation to ISV processing if site conditions allow recharge to the treatment zone at a rate faster than
the drying and melting rate. In such cases, ISV cannot be applied without some engineered provision
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for limiting recharge (e.g., slurry wall, intercept trench, temporarily lowering the water table by
pumping).
Since water removal by ISV consumes energy (about the same amount as melting soil), it is desirable
to maintain the material to be treated at as low a water content as possible. During cooling, completed
ISV melts will dry out the surrounding soil to a distance of 8 to 10 feet from the melt.
A.8.4 Processing Depth
The maximum practical depth of processing for a given site is dependent upon many factors including
media melting properties, water content and recharge conditions, and processing equipment capabilities.
The greatest single melt depth attained by Geosafe to date is slightly over 22 feet. If deeper vitrification
depths are desired, application concepts are available that involve multiple melts to achieve increased
depth (reference the "stacked" and "layering" concepts of Figure A-l). Increased single melt depth
capability is under development.
A.8.5 Total Organic Content
Treatment of organic materials results in heat generation due to the pyrolytic decomposition of organics
followed by oxidation of the pyrolysis products. This heat enters the off-gases and must be removed by
the quenching stage of the off-gas treatment system. The heat removal capability of the existing large-
scale equipment is capable of removing the heat produced from a treatment zone containing about 10
wt % organic content. This is a much higher organic loading than exists at most contaminated sites.
If it is desired to employ ISV for higher organic loadings, it would be necessary to employ equipment
with additional heat removal capacity, or to "average down" the organic loading. This can be done by
intermixing high and low contamination level media, or by adding more lowly contaminated or clean
soil to the contaminated media.
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A.8.6 Debris Content
The ISV process is unique in its ability to accommodate large amounts of various types of debris in the
treatment volume. Organic debris (e.g., plants, roots, tires, PPE, trash) will be disposed in a manner
similar to that of organic contaminants discussed above. Inorganic debris (e.g., concrete, rocks, scrap
metal) will behave similarly to earthen materials and heavy metals (i.e., dissolve into the melt).
Such debris within the treatment zone normally does not limit ISV if it is not present in such a way as
to physically interfere with the melting process, or is not present at such high quantities as to adversely
affect the melt properties. Such extreme conditions are rare at most sites, with the exception of landfills,
and particularly construction debris landfills. With proper remedial design, including the possibility of
removing or reconfiguring some debris content, the ISV process is capable of processing significant
quantities of organic and inorganic debris
Large quantities of metallic debris can also be accommodated. Metals in the reduced state (e.g., iron
scrap) normally remain in the reduced state and sink to the bottom of the ISV melt. The presence of
molten metal at the bottom of a melt actually enhances downward melt growth. By maintaining the
electrodes a short distance above the molten metal, ISV processing can continue without electrical
shorting difficulties being caused by the presence of the metal.
A.8.7 Sealed Containers
Whereas ISV has been demonstrated capable of processing sealed containers possessing a variety of
waste materials, the conditions under which such processing can be safely and reliably accomplished
have not yet been fully defined. Therefore, at this time Geosafe does not treat sites containing sealed
containers of vaporizable materials (e.g., organic liquids) on a commercial basis. Geosafe will consider
such applications on a research, development, and demonstration basis with the objective of eventual
commercial application.
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A. 8.8 Media Gas-Phase Permeability
During ISV processing, gases and vapors are generated in advance of the melt and move to the surface
through the dry zone adjacent the melt and/or through the melt itself. It is necessary that each
application be analyzed and, if necessary, designed to ensure that the gases and vapors may move to
the surface without causing excessive levels of melt disturbance.
A.9 cost
The cost of ISV is defined as Geosafe's price for ISV-related services, including treatability testing,
technical support of remedial design, and remedial action. Geosafe's price includes its direct costs for
materials, supplies, electricity, and labor; indirect costs including subcontracted services and labor
burdens; corporate overhead; and profit margin. Geosafe's price covers all activities it performs for the
client. It does not cover other activities the client may perform or have performed at a site (e.g., site
characterization, site preparation, remedial design, etc.).
The cost of treatability testing usually falls in the range of $40,000 to $80,000 of which $25,000 to
$30,000 is for performance and evaluation of the test, and the remainder ($15,000 to $50,000) is for
analytical chemistry services. The cost of treatability testing is highly dependent upon the number of
contaminants and number and types of chemical analyses that must be performed. Treatability testing
is usually performed at engineering-scale and produces a 150- to 200-pound vitrified mass. Actual
contaminated media from the site is employed in such testing at Geosafe's facilities in Richland,
Washington. In most cases, Geosafe is able to utilize engineering-scale treatability test data for large-
scale remedial design and cost estimation purposes. Geosafe also has the capability to perform one-ton
melts for larger treatability tests. Such testing can be performed in situ on the client's site if desired.
The combined cost of mobilization and demobilization of Geosafe's large-scale ISV equipment system
usually falls in the range of $300,000 to $400,000. Transportation distance from the prior site location
is a large variable determining the level of cost in this range. The mob/demob cost covers all activities
associated with transporting, setting up, readiness testing, decontamination, disassembly, and transport
away from the site.
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The equipment system is permanently mounted on three over-the-road trailers so that it is truly mobile
as opposed to transportable. The off-gas hood is transported on an additional trailer and must be erected
at the site. Additional trailers (typically two to four) are employed to transport materials and supplies
to the site (e.g., electrodes, cables, tools). Mobilization and demobilization costs are fixed costs that
should be allocated to all the tonnage involved in a remediation project.
The cost of vitrification operations currently falls in the range of $350 to $450/ton (wet density basis)
for typical non-radioactive U.S. projects. The three primary factors impacting vitrification costs are:
1) the local price of electrical power, 2) rate and depth of processing, and 3) the amount of water
requiring removal during processing. Electrical power is usually obtained at large consumer industrial
rates. Costs are less for deeper and drier sites than for shallow, wet sites. These cost estimates are based
on Geosafe's current use of a single large-scale ISV system. It is anticipated that costs will come down
as additional machines are added, which will provide a larger revenue base over which to allocate
indirect corporate costs. Costs involved with treatment of radioactive sites will be higher due to radio-
logical safety requirements.
A. 10 Regulatory and Public Acceptance
The ISV process has received good support from regulatory authorities that recognize its potential for
satisfying regulatory cleanup objectives and the regulatory preference for implementation of innovative,
on-site, in situ treatment technologies. It is noted that this support is sometimes countered by potentially
responsible party resistance against use of innovative technologies. Geosafe acknowledges the fine
support given to ISV by EPA's Technology Innovation Office, the SITE Program, and Regions IV, V,
VI, VTII, and X; and by the States of North Carolina, Michigan, Illinois, Texas, Utah, Idaho, and
Washington. Geosafe recognizes that no innovative technology may be successfully commercialized
without solid regulatory support.
ISV has also received excellent public acceptance to date. We believe that this high acceptance is due
primarily to the on-site and in situ public and environmental safety benefits of the technology, and
recognition of the superior safety and permanence of the residual vitrified product. The robustness (i.e.,
broad capabilities) of the technology, and the large volume reduction it produces are also well received
by the public. Public acceptance for ISV is also attributable to the technical credibility of the
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organizations who developed and continue to support the technology: Battelle Memorial Institute and
DOE.
A.ll Development Status and Commercial Implementability
ISV is commercially available for contaminated soil/sludge/sediment/tailings type applications. It
continues to be developed for buried waste, underground tank, barrier wall, and construction-related
applications.
The Parsons Chemical/ETM Enterprises Superfund Site was the first large-scale commercial application
of ISV. After completion of vitrification operations there, the equipment was mobilized to Spokane,
Washington for performance of a 3,500-ton TSCA demonstration project involving PCB contamination
to 17,000 mg/kg in soil that was staged to a depth of 16 feet in five treatment cells. The demonstration
was completed very successfully and on schedule. Preliminary results at the time of this writing
(November 1994) indicated very effective treatment of PCBs and full compliance with air emission
standards. PCB levels in the off-gas stack emissions were below detection limits. This demonstration
was performed in support of Geosafe's application for a National TSCA Operating Permit from EPA.
Based on the preliminary results, Geosafe is quite confident that the desired permit will be forthcoming
after EPA has completed their evaluation of the project.
After completion of the TSCA demonstration project, Geosafe mobilized its equipment to the Wasatch
Chemical Superfund Site in Salt Lake City, Utah. Here the process will be employed for treatment of
approximately 6,000 tons of soil and debris contaminated with dioxin, pentachlorophenol, numerous
pesticides, and other organics. In addition, Geosafe has obtained contracts for significant test work
involving hazardous, radioactive, and mixed waste applications for sites in Australia and Japan.
The ISV technology was originally developed for the U.S. Department of Energy (DOE), Office of
Technology Development, at the Pacific Northwest Laboratory (operated by Battelle Memorial Institute).
DOE continues to fund an ISV development program directed to exploring many possible applications
for ISV within the DOE Weapons Complex. Tests and demonstrations are being performed at engineer-
ing-, pilot-, and large-scale. The technology is scheduled for demonstration at large-scale on buried
cesium- and strontium-bearing waste at the Oak Ridge National Laboratory during the 1995 fiscal year.
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A. 12 Review of Parsons Chemical Site Experience
Geosafe considers the Parsons Chemical project to have been highly successful, while recognizing that
there were difficulties associated with it that had to be overcome. The site posed many challenges that
had not been previously experienced by Geosafe or the ISV technology. These challenges had the effect
of slowing the project down during the first few melts; however, they were all overcome and the ISV
technology was further advanced from the experience.
A. 12.1 Unusual Challenges
The site soil conditions posed the biggest challenges. Treatability testing at engineering-scale had been
successfully performed on soil from the site prior to initiation of large-scale activities. Although the
testing was useful for indicating expected treatment effectiveness, it did not provide indication of the
challenges that would be posed by the very high moisture content, high clay content soil at the site. This
soil proved to be very difficult to work with in either the wet (fully saturated, highly fluid) or dry
(concrete-like) conditions. These characteristics required special provisions for the placement of starter
paths and the operation of wheeled equipment on the site. These provisions included establishing a dry
area over the wet soil to allow proper starter path placement, stabilizing high traffic personnel and
vehicle pathways with rock, and using wood "floats" to support crane outriggers.
The saturated soil and high ambient humidity conditions resulted in unusually high moisture removal
loadings on the off-gas treatment equipment. Whereas moisture removed from the treatment zone
usually can be passed through the treatment system as humidity (water vapor), without accumulation
as liquid, the quantity of water encountered at times during the project resulted in water accumulation.
It was necessary to send this water off-site for treatment and disposal.
Water from the soil also contained dissolved solids at high enough levels to cause solids buildup
problems between the quencher and scrubber stages of the off-gas treatment system. This problem was
solved by modifying the quencher in a manner that prevented the occurrence of deposits.
When wet, the soil exhibited a noticeable sulfurous odor. In addition, a nonhazardous but noticeable
odor developed during ISV processing that was due to sulfur and organic materials in the soil. The odor
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was initially minimized during operations by minimizing the level of sulfurous buildup in the scrub
solution. The odor was eliminated midway through the project by the addition of a thermal oxidizer as
a final polishing stage of the off-gas treatment system.
The last challenge was due to site soil conditions which resulted in a greater melt width to depth ratio
than had previously been experienced with the ISV technology. This resulted in melting more clean soil
than desired adjacent to the treatment trench; it also resulted in difficulties attaining the desired depth
in the early melts. The cobble rock walls that had been placed around the designated melting region to
minimize overmelting into clean adjacent soil were found to be only partially effective for this purpose;
they slowed the lateral melt growth but did not stop it. This challenge was overcome by using refractory
barriers that effectively controlled melt width and helped attain the desired depth. A significant benefit
from the wider than expected melts was that the number of melts was reduced from nine to eight.
A. 12.2 Performance Results
The project statement of work stipulated the following performance criteria for the vitrification treatment
portion of the project:
• organic ORE of 99.999%
• production of a high integrity vitrified monolith that: 1) is highly resistant to erosion,
2) is substantially chemically inert, and 3) permanently immobilizes toxic metals and
radionuclides present in the soil;
• volume reduction of at least 10% ; and
• compliance with Michigan State air emission standards
Large amounts of performance data were acquired during the project. The SITE demonstration
performance results reported in this document are typical for the project overall. The results indicate
attainment of all the technical performance criteria, as discussed further below.
Relative to organic DRE, chemical analyses and TCLP testing confirmed the absence of organics in the
vitrified product. It is reasonable to assume zero levels of organics in the vitrified material, regardless
of analytical method detection limit capabilities due to the fact that organics cannot exist at the
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temperatures experienced in molten soil. Therefore, relative to the treatment zone itself, essentially
100% destruction and/or removal of organics was attained.
Relative to removal of organics from the off-gases, typical stack emission values for the target pesticides
were at less than detectable levels as indicated in Table A-l. Assuming the presence of contaminants
at the detection limit values, and considering the low concentrations of contaminants in the starting soil,
it was not possible to compute organic DREs with a mathematical significance beyond three nines.
Geosafe recognizes this result as an analytical limitation rather than an actual performance measure for
the ISV process. Geosafe's off-gas treatment system is qualified to produce a minimum of three nines
itself, and numerous prior tests have indicated that another two to three nines of destruction efficiency
may be expected within the treatment zone before entering the off-gases.
Relative to the vitrified monolith, a typical high integrity, chemically inert vitrified product was
produced. TCLP testing indicated full compliance for organics and all priority pollutant metals. The
required 10% minimum volume reduction was far exceeded by an actual volume reduction of about
35%.
The process was found to be in full compliance with air emission standards. Stack gas sampling was
performed many times during the project. Typical results are presented in Table A-l.
A. 12.3 Notable Achievements
Geosafe recognizes that the project had value for the ISV technology far beyond the meeting of site
cleanup and performance objectives. Since this was Geosafe's first commercial large-scale remediation
project, this project was very important for demonstrating the capabilities of Geosafe and the ISV
technology in many related areas, including:
• demonstrated applicability to high moisture (fully saturated), high clay content soils;
• demonstrated ability to process soil contaminated with organics and heavy metals;
• demonstrated ability to process debris (drum lids, tires, roots and vegetation, PPE);
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Table A-l. Off-Gas Emission Performance
Comuonent ARAR Level flb/hr) ISV Level
Mercury 5.9 x 10" 1.2 x 1CT* I
Chlordane 2.5 x 10+1 <1.1 x 10'7*
Dieldrm 2.8 x 10" <2.2 x 10'5*
DDT 1.0 x ID'2 <2.2 x 10'5*
* Detection limit value
demonstrated ability to comply with typical state ARARs, especially air emission
standards;
ability to control/eliminate odors;
demonstrated high equipment reliability;
demonstrated flexibility/adaptability of the off-gas treatment system to accommodate
varying site conditions;
demonstrated process equipment controllability;
verification of staff capabilities and remote site staffing policies;
developed methods of melt width control;
developed method of startup in fully saturated soils;
verification of thermal efficiencies;
acquisition of soil vapor pressure data adjacent to the melt, and confirmation that such
pressures do not pose problems to application of the process in tight (high clay) soils;
ability to operate during severe winter weather;
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o a good level of public acceptance for the project; and
o acquisition of cost related performance information.
Geosafe notes that overall operations efficiencies improved throughout the project. Whereas the first
four melts required about six months to complete (due somewhat to technical and regulatory delays),
the final four melts were performed in less than three months. This is indicative of the advancement of
ISV processing capability that was developed during the project.
A. 13 Review of SITE Demonstration Results
Geosafe has reviewed the SITE demonstration results presented in this document and does not take
significant issue with the information reported. Geosafe operations staff noted that the demonstration
melt was performed without any notable difficulties, and that the equipment performed flawlessly
throughout the demonstration.
Geosafe does note that the economic analysis portion of the document makes a number of assumptions
that are based on the Parsons experience but which do not represent Geosafe's current capabilities with
the ISV technology. We understand the standardized approach used for this analysis, and the necessity
to use the demonstration results as the primary basis for projections. However, we note that the Parsons
project was the first large-scale commercial remediation project performed with the ISV technology.
Geosafe made significant improvements to the equipment and process efficiencies throughout the project.
Further advances have been made since completion of the Parsons project, most notably in the areas
of reduced hood movement time and ability to control melt width and the amount of overmelting into
clean soil. Geosafe did not perform well in these two areas during the first half of the Parsons project.
That resulted in excessive time and costs which are not a good basis for estimating Geosafe's current
capabilities
Geosafe also notes that the ISV technology is quite adaptable to unusual site conditions, and that there
are many engineering means by which apparent limitations can be accommodated. Geosafe does not
fault the SITE Program for the analysis presented. However, given these considerations, Geosafe
encourages potential users to request an applicability analysis and cost estimate for specific applications
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rather than assuming that the application limitations and cost estimates presented by the SITE Program
are correct for all applications
A. 14 Acknowledgement
Geosafe acknowledges the support provided by EPA, and the fine work by Science Applications
International Corporation (SAIC), and EPA's other contractors throughout the Parsons Project and the
SITE demonstration. Geosafe believes that such support is critical to the development, demonstration,
and commercial implementation of innovative technologies.
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•& U.S. GOVERNMENT PRINTING OFFICE: 1995 651-342
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