&EPA
United States
Environmental Protection
Agency '
Rocky Mountain Remediation
Services (RMRS)
Soil Amendment Process
Innovative Technology
Evaluation Report
SUPERFUND INNOVATIVE
TECHNOLOGY EVALUATION
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EPA/540/R-02/501
July 2002
Superfund Innovative Technology
Evaluation Program
Evaluation of Soil Amendment
Technologies at the Crooksville/Roseville
Pottery Area of Concern
Rocky Mountain Remediation Services
Envirobond™ Process
Innovative Technology Evaluation Report
National Risk Management Research Laboratory
Office of Research and Development
U.S. Environmental Protection Agency
Cincinnati, Ohio 45268
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Notice
The information in this document has been funded by the U.S. Environmental Protection Agency (EPA) under
Contract No. 68-C5-0037 to TetraTech EM Inc. It has been subjected to the Agency's peer and administrative
reviews and has been approved for publication as an EPA document. Mention of trade names or commercial
products does not constitute an endorsement or recommendation for use.
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Foreword
The U.S. Environmental Protection Agency is charged by Congress with protecting the nation's land, air, and
water resources. Undera mandate of national environmental laws, the Agency strives to formulate and implement
actions leading to a compatible balance between human activities and the ability of natural systems to support
and nurture life. To meetthis mandate, EPA's research program is providing data and technical support forsolving
environmental problems today and building a science knowledge base necessary to manage our ecological
resources wisely, understand how pollutants affect our health, and prevent or reduce environmental risks in the
future.
The National Risk Management Research Laboratory is the Agency's centerfor investigation of technological
and management approaches for preventing and reducing risks from pollution thatthreatens human health and
the environment. The focus of the Laboratory's research program is on methods and theircost-effectiveness for
prevention and control of pollution to air, land, water, and subsurface resources; protection of water quality in
public watersystems; remediation of contaminated sites, sediments and ground water; prevention and control
of indoorairpollution;and restoration of ecosystems. NRMRL collaborates with both public and private sector
partners to fostertechnologiesthat reduce the cost of compliance and to anticipate emerging problems. NRMRLs
research provides solutions to environmental problems by: developing and promoting technologies that protect
and improve the environment; advancing scientificand engineering information to support regulatory and policy
decisions;and providing the technical support and information transferto ensure implementation of environmental
regulations and strategies at the national, state, and community levels.
This publication has been produced as part of the Laboratory's strategic long-term research plan. It is
published and made available by EPA's Office of Research and Development to assist the user community and
to link researchers with their clients.
E.Timothy Oppelt, Director
National Risk Management Research Laboratory
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Abstract
Rocky Mountain Remediation Services, L.L.C. (RMRS), of Golden, Colorado, has developed Envirobond™to
treat soil contaminated with metals. RMRS claims that Envirobond™ forms metal complexes that immobilize toxic
metals, thereby reducing the riskto human health and the environment.
The Superfund Innovative Technology Evaluation (SITE) Program evaluated an /ns/fu application of the technology
during a demonstration at two lead contamination sites in Roseville, Ohio, in September 1998. For the
demonstration, Envirobond™ was applied to 10 experimental units at a trailer park and one experimental unit at
an inactive pottery factory.
Primary objective 1 (P1) was to evaluate whether Envirobond™ can treat soil contaminated with lead to meetthe
Resource Conservation and Recovery Act (RCRA)/Hazardous and Solid Waste Amend ments(HSWA) alternative
universal treatment standards (UTS) for land disposal of soils contaminated with lead.The alternative UTS for
soil contaminated with lead is determined fromthe results of the toxicity characteristic leaching procedure (TCLP).
The alternative UTS is met if the concentration of lead in the TCLP extract is no higherthan one of the following:
(1) 7.5 milligrams perliter(mg/L), or(2) 10 percent ofthe lead concentration in theTCLP extract fromthe untreated
soil.Contaminated soils with TCLP lead concentrations belowthe alternative UTS meetthe RCRA land disposal
restrictions (LDR), and thus are eligible fordisposal in a land-based RCRA hazardous waste disposal unit.The
alternative UTS is defined further underTitle 40 ofthe Code of Federal Regulations (CFR), Chapter I, part 268.49
(40 CFR 268.49). To meet that objective, soil samples were collected before and after the application of
Envirobond™.The untreated and treated soil samples were analyzed forTCLP lead concentrations to evaluate
whether the technology met objective P1. Analysis ofthe data demonstrated Envirobond™ reduced the mean
TCLP lead concentration at the inactive pottery factory from 382 mg/Lto 1.4 mg/L, a reduction of more than 99
percent.Therefore, the treated soil meets the alternative UTS forsoil at the inactive pottery factory. Data fromthe
trailer park were not used to evaluate P1 because TCLP lead concentrations in all treated and untreated soil
samples from this location were either at or slightly higherthan the detection limit of 0.05 mg/L.
Primary objective 2 (P2) was to evaluate whether Envirobond™ could decrease the soil lead bioaccessibility by
25 percent or more, as defined by the Solubility/Bioaccessibility Research Consortium's (SBRC) Simplified In-
Vitro Test Method for Determining Soil Lead and Arsenic Bioaccessibility (simplified in vitro method [SIVM]).
However, EPA Lead Sites Workgroup (LSW)andTechnical Review Workgroup for lead (TRW) at this time, do not
endorse an in-vitro test for determining soil lead bioaccessibility (Interstate Technology and Regulatory
Cooperation [ITRC] 1997).To meet objective P2, soil samples were collected before and afterthe application of
Envirobond™.The soil samples were analyzed for soil lead bioaccessibility to evaluate whetherthe technology
met objective P2. Analysis ofthe data demonstrates that Envirobond™ reduced the soil lead bioaccessibility
by approximately 12.1 percent, which is less than the project goal of at least a 25 percent reduction in soil lead
bioaccessibility. However, it was recognized early on that meeting this goal would be difficult because the SIVM
test procedure used in the demonstration involves a highly acidicsample digestion process, which may be revised
in the future, because it may be exceeding the acid concentrations that would be expected in a human stomach.
An economic analysis examined 12 cost categories for a scenario in which the Envirobond ™ process was applied
at full scale to treat 807 cubic yards lead contaminated soil at a 1 -acre site within the CRPAC. The cost was
estimated to be $41.16 percubicyard of treated soil. However, the cost for using this technology is site-specific.
IV
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Contents
Notice ii
Foreword iii
Abstract iv
Acronyms, Abbreviations, and Symbols x
Table of Conversion Factors xii
Acknowledgments xiii
Executive Summary xiv
1.0 Introduction 1
1.1 Description of SITE Program and Reports 1
1.1.1 Purpose, History, Goals, and Implementation of the SITE Program 1
1.1.2 Documentation ofthe Results of SITE Demonstrations 1
1.2 Description Of Envirobond™ 2
1.3 Overview and Objectives of the SITE Demonstration 2
1.3.1 Site Background 2
1.3.2 Site Location 2
1.3.3 SITE Demonstration Objectives 2
1.3.4 Demonstration Activities 5
1.3.5 Long-term Monitoring 5
1.4 Key Contacts 5
2.0 Technology Effectiveness Analysis 7
2.1 Predemonstration Activities 7
2.2 Demonstration Activities 7
2.2.1 Activities Before Treatment 7
2.2.2 Treatment Activities 8
2.2.3 Activities AfterTreatment 8
2.3 Laboratory Analytical and Statistical Methods 11
2.3.1 Laboratory Analytical Methods 11
2.3.2 Statistical Methods 15
2.3.2.1 Determination of the Distributions of the Sample Data 15
2.3.2.2 Parametric and Distribution-free Test Statistics 15
2.4 Results of the SITE Demonstration 18
2.4.1 Evaluation of P1 18
2.4.2 Evaluation of P2 18
2.4.3 Evaluation of Objective S1 20
2.4.4 Evaluation of S2 35
2.4.5 Evaluation of Objective S3 36
2.4.6 Evaluation Of Objective S4 37
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Contents (Continued)
2.5 Quality Control Results 37
2.5.1 Completeness 37
2.5.2 Comparability and Project-required Detection Limits 39
2.5.3 Accuracy and Precision 39
2.5.4 Representativeness 39
3.0 Technology Applications Analysis 41
3.1 Description of the Technology 41
3.2 Applicable Wastes 41
3.3 Method of Application 41
3.4 Material Handling Requirements 41
3.5 Limitations of the Technology 41
3.6 Potential Regulatory Requirements 42
3.6.1 CERCLA 42
3.6.2 RCRA 42
3.6.3 OSHA 43
3.6.4 CWA 43
3.7 Availability and Transportability of the Technology 43
3.8 Community Acceptance by the State and the Community 43
4.0 Economic Analysis 44
4.1 Factors that Affect Costs 44
4.2 Assumptions of the Economic Analysis 44
4.3 Cost Categories 47
4.3.1 Site Preparation Costs 47
4.3.2 Permitting and Regulatory Costs 47
4.3.3 Mobilization Costs 48
4.3.4 Equipment Costs 48
4.3.5 Labor Costs 48
4.3.6 Supplies and Materials Costs 49
4.3.7 Utilities Costs 49
4.3.8 EffluentTreatmentand DisposalCosts 49
4.3.9 Residual Waste Shipping and Handling Costs 49
4.3.10 Analytical Services Costs 50
4.3.11 Equipment Maintenance Costs 50
4.3.12 Site Demobilization Costs 50
4.4 Summary of the Economic Analysis 51
5.0 Technology Status 52
References 53
Appendices
A Vendor Claims 54
B Case Studies 57
VI
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Figures
1-1. Location of demonstration sites in Roseville, Ohio 3
2-1. Trailer park sampling locations and patterns 9
2-2. Inactive pottery factory sampling locations and patterns 10
2-3. MEPIead results for inactive pottery factory sampling Location 1 23
2-4. MEPIead results for inactive pottery factory sampling Location 2 24
2-5. MEPIead results for inactive pottery factory sampling Locations 25
2-6. MEPIead results for inactive pottery factory sampling Location 4 26
2-7. MEPIead results for inactive pottery factory sampling Locations 27
VII
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Tables
ES-1. Evaluation of Envirobond™ by Application of the
Nine Criteria for Superfund Feasibility Studies xvi
2-1. Summary of Maximum Concentrations of Lead Observed
During Predemonstration Sampling Activities 8
2-2. Analytical Laboratory Methods 12
2-3. Summary of Extraction Procedures 14
2-4. Summary of Statistical Procedures Used to Evaluate Each of the Objectives of the
Demonstration 16
2-5. TCLP Lead Results forthe Inactive Pottery Factory Site 19
2-6. TCLP Lead Summary and Test Statistics forthe Inactive Pottery Factory Site 19
2-7. Soil Lead Bioaccessibility Results 19
2-8. ParametricTest Statistics Soil Lead Bioaccessibility Data 20
2-9. Bootstrap Statistical Results for Bioavailable Lead Difference Data 20
2-10. MEP Analytical Results 21
2-11. Summary of Percent Frequency of Lead Phases Statistical Data 28
2-12. Sequential Serial Soil Extracts Results from the Trailer Park 29
2-13. Sequential Serial Soil Extracts Results from the Inactive Pottery Factory 29
2-14. Sequential Serial Soil Extracts: Summary Statistics 30
2-15. Trailer Park Eh Analytical Results 30
2-16. Inactive Pottery Factory Eh Analytical Results 31
2-17. Eh Summary Statistics 31
2-18. Trailer Park pH Analytical Results 31
2-19. Inactive Pottery Factory pH Analytical Results 32
2-20. pH Summary Statistics 32
2-21. CEC Analytical Results for Soil from the Trailer Park 32
2-22. CEC Analytical Results for Soil from the Inactive Pottery Factory 32
VIM
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Tables (Continued)
2-23. Lead Analytical Results for Nitric Acid Digestion for Soil from the Trailer Park 33
2-24. Lead Analytical Results for Nitric Acid Digestion for Soil from the Inactive Pottery Factory 33
2-25. Summary Statistics for Nitric Acid Digestion 33
2-26. Trailer Park Lead Analytical Results Using Hydrofluoric Acid Digestion 33
2-27. Inactive Pottery Factory Lead Analytical Results Using Hydrofluoric Acid Digestion 34
2-28. Summary Statistics For Hydrofluoric Acid Digestion 34
2-29. SPLP Lead Analytical Results for Soil from the Trailer Park 35
2-30. SPLP Lead Analytical Results for Soil from the Inactive Pottery Factory 35
2-31. Total Phosphates Analytical Results for Soil from the Trailer Park 36
2-32. Total Phosphates Analytical Results for Soil from the Inactive Pottery Factory 36
2-33. SPLP Phosphates Analytical Results for Soil from the Trailer Park 36
2-34. SPLP Phosphates Analytical Results for Soil from the Inactive Pottery Factory 36
2-35. Phosphate Summary Statistics 37
Summary of Results for Objective S1 38
2-36. Air Monitoring Results 39
4-1. Cost Distribution for Envirobond™ 45
4-2. Site Preparation Costs 47
4-3. Mobilization Costs 48
4-4. Equipment Costs 48
4-5. Labor Costs 49
4-6. Supplies and Materials Costs 49
4-7. Site Demobilization Costs 51
IX
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Acronyms, Abbreviations, and Symbols
ACGIHTLV
ASTM
ARAR
BS
CaC03
CFR
CEC
CRPAC
cm3
DQO
DUP
Eh
EPA
EP-TOX
Gl
HSWA
ICP-AES
ITER
LCS
LCSD
MS
MSD
MEP
Fg/dL
Meq/g
mg/kg
mg/L
mV
NAAQS
NCP
American Conference of Governmental Industrial HygieneThreshold Limit Value
American Society forTesting and Materials
Applicable or relevant and appropriate requirements
Blankspike
Calcium carbonate
Code of Federal Regulations
Cation exchange capacity
Crooksville/Roseville Pottery Area of Concern
Cubic centimeter
Data quality objective
Duplicate
Oxidation reduction potential
U.S. Environmental Protection Agency
Extraction procedure toxicity test
U.S. Environmental Protection Agency Regional Geographic Initiative
Hazardous and Solid Waste Act
Inductively coupled plasma-atomic emission spectrometry
Innovative technology evaluation report
Laboratory control samples
Laboratory control sample duplicates
Matrix spike
Matrixspike duplicate
Multiple extraction procedure
Micrograms perdeciliter
Milliequivalents pergram
Milligram per kilogram
Milligram per liter
Millivolt
National Ambient Air Quality Standard
National Oil and Hazardous Substances Pollution Contingency Plan
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Acronyms, Abbreviations, and Symbols (continued)
NIOSHREL
NPDES
NRMRL
OEPA
ORD
OSHA
OSHAPEL
OSWER
PBET
%R
POTW
PPE
PRDL
PRP
QAPP
QA/QC
RCRA
RMRS
RPD
RPM
SARA
SBRC
SITE
SIVM
SPLP
SVOC
TCLP
TER
UTS
VOC
yd3
National Institute for Occupational Safety and Health recommended exposure limit
National Pollutant Discharge Elimination System
National Risk Management Research Laboratory
Ohio Environmental Protection Agency
Office of Research and Development
Occupation Safety and Health Administration
Occupation Safety and Health Administration permissible exposure limit
Office of Solid Waste and Emergency Response
Physiologically based extraction test
Percent recovery
Publicly owned treatment works
Personal protective equipment
Project-required detection limits
Potentially responsible party
Quality assurance project plan
Quality assurance and quality control
Resource Conservation and Recovery Act
Rocky Mountain Remediation Services, L.L.C.
Relative percent difference
Remedial Project Manager
Superfund Amendments and Reauthorization Act
Solubility/Bioavailability Research Consortium
Superfund Innovative Technology Evaluation
Simplified in-vitro method
Synthetic precipitation leaching procedure
Semivolatile organic compound
Toxicity Characteristic Leaching Procedure
Technology Evaluation Report
Microgram per kilogram
Microgram per liter
Universal treatment standard
Volatile organic compound
cubic yard
XI
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Table of Conversion Factors
Length:
Area:
Volume:
Mass:
Temperature:
To Convert from
inch
foot
mile
square foot
acre
gallon
cubic foot
cubic foot
cubic foot
cubic yard
pound
ton
(° Fahrenheit -32)
to
centimeter
meter
kilometer
square meter
square meter
liter
cubic meter
gallon
cubic centimeter
cubic meter
kilogram
kilogram
° Celsius
Multiply by
2.54
0.305
1.61
0.0929
4,047
3.78
0.0283
7.48
28,317
1.3
0.454
908
0.556
XII
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Acknowledgments
This reportwas prepared forthe U.S. Environmental Protection Agency's Office of Research and Development,
Superfund Innovative Technology Evaluation (SITE) Program byTetraTech EM Inc. under the direction and
coordination of Mr. Edwin Earth, project managerforthe SITE Program at the National Risk Management Research
Laboratory, Cincinnati, Ohio.
XIII
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Executive Summary
Rocky Mountain Remediation Services, L.L.C.(RMRS)
has developed Envirobond ™ to reduce the mobility of
metals in soils. During September 1998, an in situ
application ofthetechnologywasdemonstrated under
the U.S. Environmental Protection Agency's (EPA)
Superfund Innovative Technology Evaluation (SITE)
Program on soil contaminated with lead at two sites in
Roseville,Ohio.
The purpose of this innovative technology evaluation
report (ITER) is to present information that will assist
Superfund decision makers in evaluating Envirobond™
forapplication ata particularhazardous wastesite. This
report provides an introduction to the SITE program and
Envirobond™ and discusses the demonstration
objectives and activities (Section 1); evaluates the
technology's effectiveness (Section 2); analyzes key
factors related to application of the technology (Section
3); analyzes the costs of using the technology to reduce
the mobility of lead in soil, as well as the soil lead
bioaccessibility (Section 4); summarizes the
technology's current status (Section 5); and presents
a list of references.
This executive summary briefly summarizes the
information discussed in the ITER and evaluates the
technology with respect to the nine criteria applied in
Superfund feasibility studies.
Technology Description
RMRS claims thatthe Envirobond™ process can bind
with metals in contaminated soils, sludges, mine
tailings, process residuals, and other solid wastes.
RMRS further claims that the Envirobond™ process
converts each metal contaminant from its leachable
form to a stable, nonhazardous metallic complex.The
Envirobond™ process is a mixture of ligands that act
as chelating agents. In the chelation reaction,
coordinate bonds attach the metal ion to at least two
ligand nonmetal ions to form a heterocyclic ring. By
effectively binding the metals, RMRS claims that the
Envirobond™ process reduces the waste stream's
Toxicity Characteristic Leaching Procedure (TCLP)test
results to less than the regulated levels, subsequently
reducing the risks posed to human health and the
environment.
Overview of the SITE Demonstration
The SITE demonstration of Envirobond™ was
conducted in September 1998 at two sites in Roseville,
Ohio: an inactive pottery factory and a trailer park. Both
sites are located in the Crooksville/Roseville Pottery
AreaofConcern (CRPAC). Historically, theCRPAC was
a major pottery manufacturing area. Lead was used in
the glazing process of the pottery finishing process; as
a result, has contaminated the upper portion of the soil
layer. Soil samples collected by the Ohio Environmental
Protection Agency (OERA) in 1997 indicated that
elevated levels of lead were present in the CRPAC.
Waste disposal practices and residue from the
operation ofthe kiln at the inactive pottery factory may
have contributed to contamination ofthe soil adjacent
to the factory. Waste from several pottery factories in
the CRPAC was used as fill material in the vicinity of
the trailer park. The fill material may be the source of
the lead contamination ofthe soil at the trailer park.
For the SITE demonstration, soil samples were
collected before and afterapplication of Envirobond™
to evaluate whetherthe technology could achieve the
treatment goals ofthe demonstration project. The
project had two primary objectives and foursecondary
objectives.
The primary objectives ofthe SITE demonstration were
Primary Objective 1 (P1) - Evaluate whether
Envirobond ™ can treat soils contaminated with
lead to meet the Resource Conservation and
Recovery Act (RCRA)/Hazardous and Solid
Waste Amendments (HSWA) alternative
universal treatment standard (UTS) for land
disposal of soils contaminated with lead that
meet the definition of a hazardous waste. The
alternative UTSforlead in such soil isdetermined
from the results ofthe toxicity characteristic
leaching procedure (TCLP). The alternative UTS
for lead is met if the concentration of lead in the
TCLP extract is no higher than one ofthe
following: (1) 7.5 milligrams perliter(mg/L), or
(2) 10 percent ofthe lead concentration in the
TCLP extract from the untreated soil. The
alternative UTS is defined further in Title 40 of
the Code of Federal Regulations (CFR), Chapter
I, part 268.49 (40 CFR 268.49).
XIV
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Primary Objective 2 (P2) - Evaluate whether
Envirobond™ can decrease the soil lead
bioaccessibilityby25percentormore,asdefined
by the Solubility/Bioaccessibility Research
Consortium's (SBRC) In-Vitro Method for
Determination of Lead and Arsenic
Bioaccessibility (simplified in-vitro method
[SIVM]) (Note: the EPA Lead Sites Workgroup
(LSW) andTechnical Review Workgroupforlead
(TRW) atthis time do not endorse an in vitro test
for determining soil lead bioaccessibility [ITRC
1997]).
The secondary objectives of the demonstration were
Secondary Objective 1 (S1)-Evaluate the long-
term chemical stability of the treated soil.
Secondary Objective 2 (S2) - Demonstrate that
the application of Envirobond ™ did not increase
the public health risk of exposure to lead.
Secondary Objective 3 (S3)-Document baseline
geophysical and chemical conditions in the soil
before the application of Envirobond™.
Secondary Objective 4 (S4) - Document the
operating and design parameters of
Envirobond™.
SITE Demonstration Results
Summarized below are the significant results of the
SITEdemonstration:
Envirobond™ reduced the mean TCLP lead
concentration from 382 mg/Lto 1.4 mg/L at the
inactive pottery factory, a reduction of more than
99 percent. Therefore, the treated soil meets
the alternative UTS forsoils contaminated with
lead, as specified at CFR 268.49. Data from
the trailer park were not used to evaluate P1
because TCLP lead concentrations in all
treated and untreated soil samples from this
location were either at or slightly higherthan
the detection limit of 0.05 mg/L.
Analysis of the data generated by application of
the SIVM demonstrated that Envirobond™
reduced the soil lead bioaccessibility by
approximately 12.1 percent. However, it was
recognized early on that meeting this goal would
be difficult because the SIVM test procedure
used in the demonstration involves a highly acidic
sample digestion process, which may be revised
in the future, because it may be exceeding the
acid concentrations that would be expected in a
human stomach.
Soil treated with Envirobond™ appears to exhibit
long-term chemical stability, as indicated by the
results of most of the 11 analytical procedures
that were conducted to predict the long-term
chemical stability of the treated soil. However,
the results of some of the analytical procedures
suggest that Envirobond™ does not appear to
exhibit long-term chemical stability. In summary:
— Long-term soil chemical stability was
indicated forsoils treated by Envirobond™ at
both test locations, as indicated by the analytical
results of the multiple extraction procedure
(MEP), the procedure for lead speciation by
sequential extraction, the test for cation
exchange capacity (CEC), and leachable lead by
the simulated precipitation leaching procedure
(SPLP). The CEC results are considered to be
qualitative, because this test was conducted on
only a single sample from each location.
— Long-term chemical stability was indicated at
one site, but not at the other, by the analytical
results of procedures for evaluating acid
neutralization capacity. The acid neutralization
results are considered to be qualitative, because
this test was conducted on only a single sample
from each location.
—The analytical results from the lead speciation
test by scanning electron microscopy
(conducted only on soils from the trailer park)
were mixed, in that the silica phosphate phase
(low solubility) of lead was increased and some
soluble phases of lead were reduced, while other
low-solubility phases of lead were also reduced.
—At both locations, long-term chemical stability
was not indicated for soils treated by
Envirobond™ by the results of the pH analyses,
Eh analyses, separate analyses fortotal lead by
nitric and hydrofluoric acids; total phosphates;
and SPLP phosphates (It should be noted that
the tests involving two types of total lead analysis
were extremely aggressive tests, thus meeting
the acceptance criteria established for these
tests was not as important as meeting the
acceptance criteria of othertests involving long-
term chemical stability).
As the analytical results for the air samples
demonstrated, the dust generated during site
preparation activities prior to the application of
Envirobond™ may exceed the National Ambient
Air Quality Program Standard for lead of 1.5
micrograms per cubic meterof air. Therefore, if
it is determined that it is necessary to remove the
soil oruse othertechniques that mightgenerate
xv
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dust, it is recommended that air monitoring (with
real-time devices correlated to actual lead
concentrations in the air) be employed; and, if
necessary, dust suppression measures also
should be employed.
Based on visual observations during the
demonstration, the application of Envirobond™
does not appearto create significant quantities
ofdust.
On the basis of information obtained from the
SITE demonstration, RMRS, and othersources,
an economic analysis examined 12 cost
categories fora scenario in which Envirobond™
was applied at full scale to treat 807 cubicyards
(yd3) of soil contaminated with lead at a 1-acre
site at CRPAC. The cost estimate assumed that
the concentrations of lead in the soil were the
same as those encountered during the Roseville
demonstration. On the basis of those
assumptions, the cost was estimated to be
$41.16 per yd3 of treated soil, which is a site-
specific estimate.
Superfund Feasibility Study Evaluation Criteria for
the Envirobond™ Process
Table ES-1 presents an evaluation of Envirobond ™ with
respect to the nine evaluation criteria used for
Superfund feasibility studies that consider remedial
alternatives forsuperfund Sites.
Table ES-1. Evaluation of Envirobond™ by Application of the Nine Criteria for Superfund Feasibility Studies
Criterion
1.
2.
3.
4.
5.
6.
7.
8.
9.
Overall Protection of Human
Health and the Environment
Compliance with Applicable or
Relevant and Appropriate
Requirements (ARAR)
Long-term Effectiveness and
Permanence
Short-term Effectiveness
Reduction of Toxicity, Mobility, or
Volume Through Treatment
Implementability
Cost
Community Acceptance
State Acceptance
Discussion
The technology is expected to significantly lower the leachability of lead from soils
as indicated by the TCLP results, thereby reducing the migration of lead to
groundwater and the potential for exposure of all receptors to lead; however, the
technology did not significantly reduce soil lead bioaccessibility, as determined by
the SIVM.
During the SITE demonstration, Envirobond™ reduced the mean TCLP lead
concentration from 382 mg/L to 1 .4 mg/L, a reduction of more than 99 percent.
Further, the treated TCLP lead concentrations were less than the alternative UTS
for lead in soil. Therefore, the treated soil met the land disposal restrictions (LDR)
for lead-contaminated soil, as specified in 40 CFR 268.49. However, the
technology's ability to comply with existing federal, state, or local ARARs should be
determined on a site-specific basis.
The analytical results of procedures for the multiple extraction procedure (MEP), the
procedure for lead speciation by sequential extraction, the test for cation exchange
capacity (CEC), and leachable lead by the simulated precipitation leaching
procedure (SPLP) suggest long-term chemical stability of the treated soil. The
analytical results of a number of other procedures do not suggest long-term
chemical stability of the treated soil. Those procedures included pH analyses, Eh
analyses, separate analyses for total lead by nitric and hydrofluoric acids; total
phosphates; and SPLP phosphates. The results related to long-term effectiveness
from the test for lead speciation by scanning electron microscopy and acid
neutralization were inconclusive.
Short-term effectiveness is high; measures to control dusts and surface runoff
controls may be needed at some sites.
The mean TCLP lead concentration was reduced from 382 mg/L to 1 .4 mg/L,
reducing the mobility of the lead in the soil.
The technology is relatively easy to apply. Large areas can be treated using
common farm equipment, and small areas can be treated using readily available
home gardening tools (sod cutter, tiller, fertilizer sprayer).
For full-scale application of the technology at a 1-acre site contaminated with lead
in the top 6 inches of soil, estimated costs are $33,220, which is $41 .16 per cubic
yard.
Community acceptance of Envirobond™ likely will be a site-specific issue.
State acceptance of Envirobond™ likely will be a site-specific issue.
XVI
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Executive Summary
Rocky Mountain Remediation Services, L.L.C.(RMRS)
has developed Envirobond ™ to reduce the mobility of
metals in soils. During September 1998, an in situ
application ofthetechnologywasdemonstrated under
the U.S. Environmental Protection Agency's (EPA)
Superfund Innovative Technology Evaluation (SITE)
Program on soil contaminated with lead at two sites in
Roseville,Ohio.
The purpose of this innovative technology evaluation
report (ITER) is to present information that will assist
Superfund decision makers in evaluating Envirobond™
forapplication ata particularhazardous wastesite. This
report provides an introduction to the SITE program and
Envirobond™ and discusses the demonstration
objectives and activities (Section 1); evaluates the
technology's effectiveness (Section 2); analyzes key
factors related to application of the technology (Section
3); analyzes the costs of using the technology to reduce
the mobility of lead in soil, as well as the soil lead
bioaccessibility (Section 4); summarizes the
technology's current status (Section 5); and presents
a list of references.
This executive summary briefly summarizes the
information discussed in the ITER and evaluates the
technology with respect to the nine criteria applied in
Superfund feasibility studies.
Technology Description
RMRS claims thatthe Envirobond™ process can bind
with metals in contaminated soils, sludges, mine
tailings, process residuals, and other solid wastes.
RMRS further claims that the Envirobond™ process
converts each metal contaminant from its leachable
form to a stable, nonhazardous metallic complex.The
Envirobond™ process is a mixture of ligands that act
as chelating agents. In the chelation reaction,
coordinate bonds attach the metal ion to at least two
ligand nonmetal ions to form a heterocyclic ring. By
effectively binding the metals, RMRS claims that the
Envirobond™ process reduces the waste stream's
Toxicity Characteristic Leaching Procedure (TCLP)test
results to less than the regulated levels, subsequently
reducing the risks posed to human health and the
environment.
Overview of the SITE Demonstration
The SITE demonstration of Envirobond™ was
conducted in September 1998 at two sites in Roseville,
Ohio: an inactive pottery factory and a trailer park. Both
sites are located in the Crooksville/Roseville Pottery
AreaofConcern (CRPAC). Historically, theCRPAC was
a major pottery manufacturing area. Lead was used in
the glazing process of the pottery finishing process; as
a result, has contaminated the upper portion of the soil
layer. Soil samples collected by the Ohio Environmental
Protection Agency (OERA) in 1997 indicated that
elevated levels of lead were present in the CRPAC.
Waste disposal practices and residue from the
operation ofthe kiln at the inactive pottery factory may
have contributed to contamination ofthe soil adjacent
to the factory. Waste from several pottery factories in
the CRPAC was used as fill material in the vicinity of
the trailer park. The fill material may be the source of
the lead contamination ofthe soil at the trailer park.
For the SITE demonstration, soil samples were
collected before and afterapplication of Envirobond™
to evaluate whetherthe technology could achieve the
treatment goals ofthe demonstration project. The
project had two primary objectives and foursecondary
objectives.
The primary objectives ofthe SITE demonstration were
Primary Objective 1 (P1) - Evaluate whether
Envirobond ™ can treat soils contaminated with
lead to meet the Resource Conservation and
Recovery Act (RCRA)/Hazardous and Solid
Waste Amendments (HSWA) alternative
universal treatment standard (UTS) for land
disposal of soils contaminated with lead that
meet the definition of a hazardous waste. The
alternative UTSforlead in such soil isdetermined
from the results ofthe toxicity characteristic
leaching procedure (TCLP). The alternative UTS
for lead is met if the concentration of lead in the
TCLP extract is no higher than one ofthe
following: (1) 7.5 milligrams perliter(mg/L), or
(2) 10 percent ofthe lead concentration in the
TCLP extract from the untreated soil. The
alternative UTS is defined further in Title 40 of
the Code of Federal Regulations (CFR), Chapter
I, part 268.49 (40 CFR 268.49).
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Primary Objective 2 (P2) - Evaluate whether
Envirobond™ can decrease the soil lead
bioaccessibilityby25percentormore,asdefined
by the Solubility/Bioaccessibility Research
Consortium's (SBRC) In-Vitro Method for
Determination of Lead and Arsenic
Bioaccessibility (simplified in-vitro method
[SIVM]) (Note: the EPA Lead Sites Workgroup
(LSW) andTechnical Review Workgroupforlead
(TRW) atthis time do not endorse an in vitro test
for determining soil lead bioaccessibility [ITRC
1997]).
The secondary objectives of the demonstration were
Secondary Objective 1 (S1)-Evaluate the long-
term chemical stability of the treated soil.
Secondary Objective 2 (S2) - Demonstrate that
the application of Envirobond ™ did not increase
the public health risk of exposure to lead.
Secondary Objective 3 (S3)-Document baseline
geophysical and chemical conditions in the soil
before the application of Envirobond™.
Secondary Objective 4 (S4) - Document the
operating and design parameters of
Envirobond™.
SITE Demonstration Results
Summarized below are the significant results of the
SITEdemonstration:
Envirobond™ reduced the mean TCLP lead
concentration from 382 mg/Lto 1.4 mg/L at the
inactive pottery factory, a reduction of more than
99 percent. Therefore, the treated soil meets
the alternative UTS forsoils contaminated with
lead, as specified at CFR 268.49. Data from
the trailer park were not used to evaluate P1
because TCLP lead concentrations in all
treated and untreated soil samples from this
location were either at or slightly higherthan
the detection limit of 0.05 mg/L.
Analysis of the data generated by application of
the SIVM demonstrated that Envirobond™
reduced the soil lead bioaccessibility by
approximately 12.1 percent. However, it was
recognized early on that meeting this goal would
be difficult because the SIVM test procedure
used in the demonstration involves a highly acidic
sample digestion process, which may be revised
in the future, because it may be exceeding the
acid concentrations that would be expected in a
human stomach.
Soil treated with Envirobond™ appears to exhibit
long-term chemical stability, as indicated by the
results of most of the 11 analytical procedures
that were conducted to predict the long-term
chemical stability of the treated soil. However,
the results of some of the analytical procedures
suggest that Envirobond™ does not appear to
exhibit long-term chemical stability. In summary:
— Long-term soil chemical stability was
indicated forsoils treated by Envirobond™ at
both test locations, as indicated by the analytical
results of the multiple extraction procedure
(MEP), the procedure for lead speciation by
sequential extraction, the test for cation
exchange capacity (CEC), and leachable lead by
the simulated precipitation leaching procedure
(SPLP). The CEC results are considered to be
qualitative, because this test was conducted on
only a single sample from each location.
— Long-term chemical stability was indicated at
one site, but not at the other, by the analytical
results of procedures for evaluating acid
neutralization capacity. The acid neutralization
results are considered to be qualitative, because
this test was conducted on only a single sample
from each location.
—The analytical results from the lead speciation
test by scanning electron microscopy
(conducted only on soils from the trailer park)
were mixed, in that the silica phosphate phase
(low solubility) of lead was increased and some
soluble phases of lead were reduced, while other
low-solubility phases of lead were also reduced.
—At both locations, long-term chemical stability
was not indicated for soils treated by
Envirobond™ by the results of the pH analyses,
Eh analyses, separate analyses fortotal lead by
nitric and hydrofluoric acids; total phosphates;
and SPLP phosphates (It should be noted that
the tests involving two types of total lead analysis
were extremely aggressive tests, thus meeting
the acceptance criteria established for these
tests was not as important as meeting the
acceptance criteria of othertests involving long-
term chemical stability).
As the analytical results for the air samples
demonstrated, the dust generated during site
preparation activities prior to the application of
Envirobond™ may exceed the National Ambient
Air Quality Program Standard for lead of 1.5
micrograms per cubic meterof air. Therefore, if
it is determined that it is necessary to remove the
soil oruse othertechniques that mightgenerate
xv
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dust, it is recommended that air monitoring (with
real-time devices correlated to actual lead
concentrations in the air) be employed; and, if
necessary, dust suppression measures also
should be employed.
Based on visual observations during the
demonstration, the application of Envirobond™
does not appearto create significant quantities
ofdust.
On the basis of information obtained from the
SITE demonstration, RMRS, and othersources,
an economic analysis examined 12 cost
categories fora scenario in which Envirobond™
was applied at full scale to treat 807 cubicyards
(yd3) of soil contaminated with lead at a 1-acre
site at CRPAC. The cost estimate assumed that
the concentrations of lead in the soil were the
same as those encountered during the Roseville
demonstration. On the basis of those
assumptions, the cost was estimated to be
$41.16 per yd3 of treated soil, which is a site-
specific estimate.
Superfund Feasibility Study Evaluation Criteria for
the Envirobond™ Process
Table ES-1 presents an evaluation of Envirobond ™ with
respect to the nine evaluation criteria used for
Superfund feasibility studies that consider remedial
alternatives forsuperfund Sites.
Table ES-1. Evaluation of Envirobond™ by Application of the Nine Criteria for Superfund Feasibility Studies
Criterion
1.
2.
3.
4.
5.
6.
7.
8.
9.
Overall Protection of Human
Health and the Environment
Compliance with Applicable or
Relevant and Appropriate
Requirements (ARAR)
Long-term Effectiveness and
Permanence
Short-term Effectiveness
Reduction of Toxicity, Mobility, or
Volume Through Treatment
Implementability
Cost
Community Acceptance
State Acceptance
Discussion
The technology is expected to significantly lower the leachability of lead from soils
as indicated by the TCLP results, thereby reducing the migration of lead to
groundwater and the potential for exposure of all receptors to lead; however, the
technology did not significantly reduce soil lead bioaccessibility, as determined by
the SIVM.
During the SITE demonstration, Envirobond™ reduced the mean TCLP lead
concentration from 382 mg/L to 1 .4 mg/L, a reduction of more than 99 percent.
Further, the treated TCLP lead concentrations were less than the alternative UTS
for lead in soil. Therefore, the treated soil met the land disposal restrictions (LDR)
for lead-contaminated soil, as specified in 40 CFR 268.49. However, the
technology's ability to comply with existing federal, state, or local ARARs should be
determined on a site-specific basis.
The analytical results of procedures for the multiple extraction procedure (MEP), the
procedure for lead speciation by sequential extraction, the test for cation exchange
capacity (CEC), and leachable lead by the simulated precipitation leaching
procedure (SPLP) suggest long-term chemical stability of the treated soil. The
analytical results of a number of other procedures do not suggest long-term
chemical stability of the treated soil. Those procedures included pH analyses, Eh
analyses, separate analyses for total lead by nitric and hydrofluoric acids; total
phosphates; and SPLP phosphates. The results related to long-term effectiveness
from the test for lead speciation by scanning electron microscopy and acid
neutralization were inconclusive.
Short-term effectiveness is high; measures to control dusts and surface runoff
controls may be needed at some sites.
The mean TCLP lead concentration was reduced from 382 mg/L to 1 .4 mg/L,
reducing the mobility of the lead in the soil.
The technology is relatively easy to apply. Large areas can be treated using
common farm equipment, and small areas can be treated using readily available
home gardening tools (sod cutter, tiller, fertilizer sprayer).
For full-scale application of the technology at a 1-acre site contaminated with lead
in the top 6 inches of soil, estimated costs are $33,220, which is $41 .16 per cubic
yard.
Community acceptance of Envirobond™ likely will be a site-specific issue.
State acceptance of Envirobond™ likely will be a site-specific issue.
XVI
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1.0 Introduction
This section provides background information about the
Superfund Innovative Technology Evaluation (SITE) Pro-
gram and reports related to it; describes Envirobond™;
presents the objectives of the SITE demonstration; and
provides information about key contacts.
1.1 Description of SITE Program and
Reports
This section provides information about the purpose, his-
tory, goals, and implementation of the SITE program, and
about reports that document the results of SITE demon-
strations.
1.1.1 Purpose, History, Goals, and
Implementation of the SITE Program
The primary purpose of the SITE program is to advance
the development and demonstration, and thereby estab-
lish the commercial availability, of innovative treatment
technologies applicable to Superfund and other hazardous
waste sites. The SITE program was established by the
U.S. Environmental Protection Agency's (EPA) 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), which recognizes the need for an alterna-
tive or innovative treatment technology research and dem-
onstration program.The SITE program is administered by
ORD's National Risk Management Research Laboratory
(NRMRL) in Cincinnati, Ohio. The overall goal of the SITE
program is to carry out a program of research, evaluation,
testing, development, and demonstration of alternative or
innovative treatment technologies that can be used in re-
sponse actions to achieve more permanent protection of
human health and the environment.
Each SITE demonstration evaluates the performance of a
technology in treating a specific waste. The waste charac-
teristics at other sites may differ from the characteristics
of those treated during the SITE demonstration. Further,
the successful field demonstration of a technology at one
site does not necessarily ensure that it will be applicable
at other sites. Finally, data from the field demonstration may
require extrapolation to estimate (1) the operating ranges
under which the technology will perform satisfactorily and
(2) the costs associated with application of the technology.
Therefore, only limited conclusions can be drawn from a
single field demonstration, such as a SITE technology
demonstration.
The SITE program consists of four components: (1) the
Demonstration Program, (2) the Emerging Technology
Program, (3) the Monitoring and Measurement Technolo-
gies Program, and (4) the Technology Transfer Program.
The SITE demonstration described in this innovative tech-
nology evaluation report (ITER) was conducted underthe
Demonstration Program. The objective of the Demonstra-
tion Program is to provide reliable performance and cost
data on innovative technologies so that potential users can
assess a given technology's suitability for cleanup of a
specific site. To produce useful and reliable data, demon-
strations are conducted at hazardous waste sites or un-
der conditions that closely simulate actual conditions at
waste sites.The program's rigorous quality assurance and
quality control (QA/QC) procedures provide for objective
and carefully controlled testing of field-ready technologies.
Innovative technologies chosen for a SITE demonstration
must be pilot- or full-scale applications and must offer
some advantage over existing technologies.
Implementation of the SITE program is a significant, on-
going effort that involves OSWER, ORD, various EPA re-
gions, and private business concerns, including
technology developers and parties responsible for site
remediation. Cooperative agreements between EPA and
the innovative technology developer establish responsibili-
ties for conducting the demonstrations and evaluating the
technology. The developer typically is responsible fordem-
onstrating the technology at the selected site and is ex-
pected to pay any costs of transportation, operation, and
removal of related equipment. EPA typically is responsible
for project planning, site preparation, provision of techni-
cal assistance, sampling and analysis, QA/QC, prepara-
tion of reports, dissemination of information, and
transportation and disposal of treated waste materials.
1.1.2 Documentation of the Results of SITE
Demonstrations
The results of each SITE demonstration are reported in an
ITER and a technology evaluation report(TER).The ITER
is intended for use by EPA remedial project managers
(RPM) and on-scene coordinators, contractors, and oth-
ers involved in the remediation decision-making process
and in the implementation of specific remedial actions.The
ITER is designed to aid decision makers in determining
whether specific technologies warrant further consider-
ation as options applicable to particular cleanup opera-
tions. To encourage the general use of demonstrated
technologies, EPA provides information about the applica-
bility of each technology to specific sites and wastes. The
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ITER provides information about costs and site-specific
characteristics. It also discusses the advantages, disad-
vantages, and limitations of the technology.
The purpose of the TER is to consolidate all information
and records acquired during the demonstration.The TER
presents both a narrative and tables and graphs that sum-
marize data. The narrative discusses predemonstration,
demonstration, and postdemonstration activities, as well
as any deviations from the quality assurance project plan
(QAPP) forthe demonstration during those activities and
the effects of such deviations. The data tables summarize
the QA/QC data. EPA does not publish the TER; instead,
a copy is retained as a reference by the EPA project man-
ager for use in responding to public inquiries and for
recordkeeping purposes.
1.2 Description of Envirobond™
The Envirobond™ process is a combination of a propri-
etary powder and solution that binds with metals in con-
taminated soils and other wastes. Rocky Mountain
Remediation Services, L.L.C. (RMRS), the developer of
the process, claims that the Envirobond™ process effec-
tively prevents metals from leaching and can be used with
mechanical compaction to reduce the overall volume of
contaminated media by 30 to 50 percent. The
Envirobond™ process generates no secondary wastes
and involves minimal handling, transportation, and dis-
posal costs.
The Envirobond™ process consists of a mixture of addi-
tives containing oxygen, nitrogen, and phosphorous; each
additive has an affinity fora specific class of metals. RMRS
claims that the Envirobond™ process converts each metal
contaminant from its leachable form to an insoluble, stable,
nonhazardous metallic complex.The Envirobond™ pro-
cess is essentially a mixture of ligands that act as chelat-
ing agents. In the chelation reaction, coordinate bonds
attach the metal ion to at least two ligand nonmetal ions
to form a heterocyclic ring. The resulting ring structure is
inherently more stable than simpler structures formed in
many binding processes. RMRS claims that, by effectively
binding the metals, the Envirobond™ process reduces the
waste stream's leachable metal concentrations to less than
regulated levels, and thereby reduces the risks posed to
human health and the environment.
The Envirobond™ process can be deployed as an in situ
or ex situ treatment process. RMRS reports that the
Envirobond™ process is capable of achieving processing
rates of 20 to 40 tons per hour for ex situ treatment and can
be used with contaminated media containing as much as
10 percent debris.
1.3 Overview and Objectives of the SITE
Demonstration
This section provides information about (1) the site back-
ground and location, (2) the objectives of the SITE dem-
onstration, (3) demonstration activities, and (4) long-term
monitoring activities.
1.3.1 Site Background
The villages of Crooksville and Roseville, located along the
Muskingum and Perry County line in eastern Ohio, are
famous for a long history of pottery production. During the
100-year period of pottery manufacturing in those villages,
broken and defective (off-specification [off-spec]) pottery
was disposed of in several areas. Disposal practices were
not monitored or documented clearly. Sampling conducted
in the region by the Ohio Environmental Protection Agency
(OEPA) in 1997 identified 14 former potteries and pottery
disposal sites at which significant lead contamination was
present. Results of analysis of the soil samples collected
by OEPA in 1997 indicated elevated levels of lead in shal-
low soils throughout the area (OEPA 1998) identified as the
Crooksville/Roseville Pottery Area of Concern (CRPAC).
Much of the lead contamination is associated with the dis-
posal of unused glazing materials or of off-spec pottery
that was not fired in a kiln.
In 1996, OEPA entered into a cooperative agreement with
EPA to conduct an investigation of the CRPAC under a
regional geographic initiative (GI).The Gl program pro-
vides grants for projects that an EPA region, a state, or a
locality has identified as high priority and at which the po-
tential for risk reduction is significant.The Gl program al-
lows EPA regions to address unique, multimedia regional
environmental problems that may pose risks to human
health orto the environment, such as the widespread lead
contamination found at the CRPAC.
The purpose of the Gl of the investigation of the CRPAC
was to determine whether the long history of pottery op-
erations there, from the late 1800s through the 1960s,
caused any increases over background levels of concen-
trations of heavy metals in soil, groundwater, surface wa-
ter, or air. The results of analysis of soil and groundwater
samples collected in 1997 indicate elevated levels of lead
are present in shallow soils and groundwater throughout
the CRPAC (OEPA 1998).
1.3.2 Site Location
OEPA selected four potential demonstration sites in the
CRPAC on the basis of the analytical results for samples
collected as part of the Gl. Before the demonstration was
conducted, SITE personnel collected and analyzed soil
samples from the potential demonstration sites to deter-
mine the extent of the lead contamination at those sites.
On the basis of the analytical results and discussions with
representatives of OEPA, two sites in the CRPAC were
selected forthe SITE demonstration project. One site is a
formertrailerparkin Roseville, Ohio, which is one of many
residential areas in the CRPAC that have been affected by
the disposal of the pottery waste. The other site, also in
Roseville, Ohio, is located in an industrial area, adjacent
to an inactive pottery factory. Figure 1-1 shows the loca-
tions of the demonstration sites.
1.3.3 SITE Demonstration Objectives
OEPA applied to the SITE program for assistance in evalu-
ating innovative, cost-effective technologies that could be
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Inactive Pottery Factory! •*
NOT TO SCALE
CRPAC
En virobond™ Demonstration
FIGURE 1-1
Location of Demonstration Sites in Roseville, Ohio
Tetra Tech EM Inc.
Figure 1-1. Location of demonstration sites in Roseville, Ohio.
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applied at the CRPAC. OEPA was considering excavating
the soil and stabilizing it with Portland cement; however, the
agency also sought to evaluate an innovative technology
that could be applied in lieu of soil excavation and that was
lower in cost than the cement-based soil stabilization tech-
nology. OEPA indicated that children in the CRPAC exhib-
ited higher blood concentrations of lead than children in
areas that are not affected by the waste disposal practices
of the pottery factories. Therefore, OEPA also was inter-
ested in identifying a technology that could reduce the risk
of direct exposure to lead in the soil at the CRPAC.To meet
OEPA's needs, the SITE program recommended the evalu-
ation of Envirobond™ because it is a technology that can
be applied in situ with standard construction or farm equip-
ment. EPA refined the objectives of the demonstration
project during a meeting with OEPA on March 19, 1998.
During and following this meeting, EPA and OEPA estab-
lished primary and secondary objectives for the SITE dem-
onstration. The objectives were based on EPA's
understanding of the technology; information provided by
the developers of Envirobond™; the needs identified by
OEPA; and the goals of the SITE demonstration program,
which include providing potential users of Envirobond™
with technical information to be used in determining
whetherthe technology is applicable to other contaminated
sites.
The objectives of the demonstration originally were defined
in the EPA-approved QAPP dated November 1998 (Tetra
Tech 1998).The two primary objectives are structured to
evaluate the ability of the technology to reduce the leach-
able and bioaccessible concentrations of lead in soils, re-
spectively. The secondary objectives are structured to
evaluate the technology's ability to meet other performance
goals not considered critical, to document conditions at the
site, to document the operating and design parameters of
the technology, and to determine the costs of applying the
technology.
Primary Objectives
Two primary objectives were developed forthe demonstra-
tion.
Primary objective 1 (P1) was to evaluate whether
leachable lead in soil can be reduced to concentra-
tions that comply with the alternative UTS for lead
in contaminated soil, which are codified at 40 Code
of Federal Regulations (CFR) part 268.49 and are
included in the land disposal requirements (LDR) set
forth underthe Resource Conservation and Recov-
ery Act (RCRA)/Hazardous and Solid Waste
Amendments (HSWA).
Primary objective 2 (P2) was to determine whether
the portion of total lead in soil that is "bioaccessible,"
as measured by an experimental method, could be
reduced by at least 25 percent. However, it was rec-
ognized early on that meeting this goal would be
difficult because the SIVM test procedure used in
the demonstration involves a highly acidic sample
digestion process, which may be revised in the fu-
ture, because it may be exceeding the acid concen-
trations that would be expected in a human stom-
ach.
Each of the objectives is described below.
Concentrations of lead in contaminated soils that are the
subject of cleanup actions often meet the definition of a
hazardous waste under RCRA/HSWA. Sometimes, the
goals forsuch cleanup actions include a requirement that
the soil be treated, either/ns/fu or ex s/fu, to the point that
it is in compliance with the LDRs set forth under RCRA/
HSWA. A common reason for including such a treatment
goal is to ensure that the lead in treated soil is immobilized
sufficiently to make it unlikely that the soil will migrate to
groundwater. A treated soil is deemed to be in compliance
with the LDRs for lead if the concentration of lead, as mea-
sured by a TCLP analysis, is 90 percent lower than the
concentration of untreated soil or the treated soil is less
than or equal to 7.5 milligrams per liter (mg/L). Objective
P1 forthis demonstration required that the mean concen-
tration of TCLP lead in the treated soil be 90 percent lower
than the concentration in untreated soil or less than or
equal to 7.5 mg/L. In addition, the objective required the
use of statistical analyses of mean concentrations of TCLP
lead, in which the alpha level was set at 0.05.
Bioaccessibility of lead is not normally measured at con-
taminated sites. The treatment goals for sites at which the
soil is contaminated with lead usually are based on the
results obtained from lead exposure models that can cal-
culate a maximum total concentration of lead in soil that
will not cause blood concentrations of lead in children that
exceed the widely accepted threshold level of 10 micro-
grams per deciliter (Fg/dL). Such models often include a
factor that determines the portion of total lead (after inges-
tion) that is bioavailable. Bioavailability refers to that por-
tion of total soil lead that is absorbed into the bloodstream
from the ingestion of the soil (Interstate Technology and
Regulatory Cooperation [ITRC] 1997); it is determined
through the use of a number of techniques approved by
EPA that incorporate the results of in-vivo tests.
"Bioaccessibility" of soil lead has been proposed as a term
that refers to the results of simpler, in-vitro tests that can
be used as indicators of the bioavailability of soil lead. One
such test method is the In-Vitro Method for Determination
of Lead and Arsenic Bioaccessibility (or simplified in vitro
method [SIVM]), which was developed by the Solubility/
Bioaccessibility Research Consortium (SBRC) (ITRC
1997).The test simulates digestion of ingested lead in soil,
using a combination of chemicals found in the human
stomach. Although the EPA Lead Sites Workgroup (LSW)
and Technical Review Workgroup (TRW) for lead currently
do not endorse an in vitro test for determining soil lead
bioavailability (ITRC 1997), such tests, if endorsed in the
future, have the potential for use in rapid evaluation of the
ability of soil treatment chemicals to reduce the total con-
centrations of bioavailable lead.The SIVM currently is un-
dergoing validation studies. In previous studies, the test
results correlated well with results of analysis by in vivo for
soil lead tests based on the Sprague-Dawley rat model and
a swine model (ITRC 1997). Primary objective P2 was to
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evaluate whether Envirobond™ could decrease the
bioaccessibility of soil lead (as measured by the SIVM) by
25 percent or more. In addition, the objective required the
use of statistical analyses of mean percent lead concen-
trations, in which the alpha level was set at 0.05.
Secondary (S) Objectives
Secondary objectives were established to collect addi-
tional data considered useful, but not critical, to the evalu-
ation of Envirobond™. The secondary objectives of the
demonstration were as follows:
Secondary Objective 1 (S1) - Evaluate the long-term
chemical stability of the treated soil.
Secondary Objective 2 (S2) - Demonstrate that the
application of Envirobond™ did not increase the
public health risk of exposure to lead.
Secondary Objective 3 (S3) - Document baseline
geophysical and chemical conditions in the soil be-
fore the addition of Envirobond™.
Secondary Objective 4 (S4) - Document operating
and design parameters of Envirobond™.
S1 was to determine whether Envirobond™ can enhance
the long-term chemical stability of the treated soil. Long-
term chemical stability is demonstrated most convincingly
through an extended monitoring program. However, the
results of such programs may not be available for several
years. Therefore, a number of alternative analytical proce-
dures were selected and applied to untreated and treated
soils collected from both sites.Those procedures included
the multiple extraction procedure (MEP), lead speciation
using a scanning electron microscope (SEM), lead specia-
tion with a sequential extraction procedure, oxidation-re-
duction potential (Eh), pH, cation exchange capacity
(CEC), acid neutralization capacity, total lead (as deter-
mined by two different methods), leachable lead by the
synthetic precipitation leaching procedure (SPLP), total
phosphates, and SPLP-leachable phosphates.The evalu-
ation was accomplished by comparing the results of the
analytical procedures on soil samples collected from both
sites before and after application of Envirobond™. Section
2.3 of this ITER provides additional details about each
analytical procedure and the criteria applied in interpret-
ing the results obtained.
S2 was to determine whether the dust generated during
the application of Envirobond™ may increase risks to the
public health posed by inhalation of lead during full-scale
implementation.The evaluation was accomplished by ana-
lyzing residuals from air samples that were drawn through
filters during those demonstration activities that could cre-
ate dust and comparing the analytical results with the
National Ambient Air Quality Standard (NAAQS) for lead.
S3 was to evaluate baseline geophysical and chemical
properties of the soil at both sites. The objective was ac-
complished by classifying soil samples from both sites and
analyzing them for volatile organic compounds (VOC),
semivolatile organic compounds (SVOC), oil and grease,
and humic and fulvic acids.
S4 was to estimate the costs associated with the use of
Envirobond™. The cost estimates were based on obser-
vations made and data obtained during and afterthe dem-
onstration, as well as data provided by RMRS.
1.3.4 Demonstration Activities
Personnel of the SITE program evaluated the objectives
of the demonstration by collecting and analyzing surficial
soil samples before and after Envirobond™ was applied.
Soil samples collected from the inactive pottery factory and
the trailer park were used in determining success in ac-
complishing objective P1. In the case of P2, only soil
samples collected from the trailer park were used. In gen-
eral, five types of data were obtained: (1)TCLP lead con-
centrations in untreated and treated soils; (2)
bioaccessibility levels of lead in untreated and treated soils;
(3) various levels of parameters for evaluating the long-
term chemical stability of untreated and treated soils; (4)
concentrations of lead in airduring sampling and treatment
activities; and (5) levels of baseline geophysical and chemi-
cal parameters in untreated soils. The sampling program
was designed specifically to support the demonstration
objectives presented in Section 1.3.3. Section 2.0 of this
ITER discusses the results of the evaluation.
1.3.5 Long-term Monitoring
A long-term monitoring program was established; under
that program, additional samples of soil are to be collected
quarterly and analyzed for soil lead bioaccessibility, TCLP
lead, concentrations of SPLP lead, and concentrations of
lead in groundwater. Water samples will be collected quar-
terly from lysimeters installed in experimental units at both
sites and analyzed for lead. Samples of grass will be col-
lected from experimental units at the trailer park. Informa-
tion obtained through the long-term monitoring effort will
be presented in reports to be issued periodically as the
long-term monitoring program proceeds.
1.4 Key Contacts
Additional information about the SITE program,
Envirobond™, RMRS, OEPA, and the analytical laborato-
ries is available from the following sources:
EPA Project Manager
Edwin Earth
LRPCD
Office of Research and Development
U.S. Environmental Protection Agency
26 W. Martin Luther King Drive
Cincinnati, OH 45268
(513)569-7669
(513)569-7571 (fax)
e-mail: barth. ed@epamail. epa. gov
EPA QA Manager
Ann Vega
Office of Research and Development
U.S. Environmental Protection Agency
-------
26 W. Martin Luther King Drive
Cincinnati, OH 45268
(513)569-7635
(513) 569-7585 (fax)
e-mail: vega. ann@epamail. epa. gov
Technology Developer
AliSogue
Rocky Mountain Remediation Services
1819 Denver West Drive
Building 26, Suite 200
Golden, Colorado 80401
(303)215-6686
(303) 215-6786 (fax)
E-mail: asogue@rmrshq.com
TetraTech Project Manager
Mark Evans
TetraTech EM Inc.
1881 Campus Commons Drive, Suite 200
Reston,VA20191
(703)390-0637
(703) 391-5876 (fax)
e-mail: evansm@ttemi.com
Tetra Tech QA Manager
Greg Swanson
TetraTech EM Inc.
591 Camino de la Reina, Suite 640
San Diego, CA 92108
(619)718-9676
(619) 718-9698 (fax)
e-mail: swansog@ttemi.com
Analytical Laboratory Managers
Jamie McKinney
Quanterra Analytical Services
5815MiddlebrookPike
Knoxville, TN 37921
(423) 588-6401
(423) 584-4315 (fax)
e-mail: mckinney@quanterra. com
John Drexler
Department of Geology
University of Colorado
2200 Colorado Avenue
Boulder, CO 80309
(303) 492-5251
(303) 492-2606 (fax)
e-mail: drexlerj@spot. Colorado, edu
David Germeroth
Maxim Technologies, Inc.
1908 Innerbelt Business Center Drive
St. Louis, MO 63114-5700
(314)426-0880
(314) 426-4212 (fax)
e-mail: dgermero. stlouis@maximmail. com
Steve Hall
Kiber Environmental Services
3145 Medlock Bridge Road
Norcross, GA 30071
(770)242-4090,ext.285
(770) 242-9198 (fax)
e-mail: stevehall@kiber.com
Rob Liversage
Data Chem Laboratory
4388 Glendale-Milford Road
Cincinnati, OH 45242
(513)733-5336
(513) 733-5347 (fax)
e-mail: rob@datachemlabs. com
Ohio EPA
Abby Lavelle
Southeast District Office
Ohio Environmental Protection Agency
2195 Front Street
Logan, OH 43139-9031
(740) 380-5296
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2.0 Technology Effectiveness Analysis
This section addresses the effectiveness of Envirobond™
as observed during the demonstration of the technology
at the selected sites at the CRPAC. Section 2.1 describes
the predemonstration activities that lead to the selection
of the two locations forthe demonstration; Section 2.2 pre-
sents the activities conducted during the demonstration,
including the establishment of experimental units at each
demonstration site, and the collection of untreated and
treated soil samples; Section 2.3 describes the laboratory
analytical and statistical methods used to evaluate dem-
onstration objectives; Section 2.4 presents results of the
demonstration; and Section 2.5 provides a summary of
results obtained from the analysis of quality control
samples that were collected during the demonstration.
2.1 Predemonstration Activities
Predemonstration activities included preliminary sampling
at four candidate locations, followed by selection of two
demonstrations sites. In March 1998, site personnel col-
lected soil samples from four locations that had been iden-
tified by OEPA as potential demonstration sites. Three of
the locations were at pottery factories, and the other loca-
tion was at a former trailer park that had been constructed
on property contaminated with pottery wastes. At all four
locations, field measurements of total lead concentrations
were made with an x-ray fluorescence (XRF) analyzer, and
additional samples were collected for laboratory analysis
of total lead, leachable lead (by theTCLP and SPLP), and
soil lead bioaccessibility (by the SIVM).Table 2-1 presents
the highest concentrations of lead measured at each of the
four locations. The highest concentrations of lead mea-
sured in the field by XRF analyzers are higherthan those
measured in the laboratory because samples for labora-
tory measurements were not collected at exact locations
where the highest field concentrations of lead were de-
tected. As Table 2-1 indicates, the two locations selected
forthe SITE demonstration were the inactive pottery fac-
tory in Roseville, Ohio, and the trailer park, also in
Roseville.The principal reasons forthe selection of the
inactive pottery factory in Roseville were that it appeared
to have higher concentrations of lead than any of the other
locations and it was more readily accessible than the other
pottery factories. The trailer park was selected forthe SITE
demonstration primarily because use of that site would
allow evaluation of the Envirobond™ technology at sites
at which concentrations of lead in soil were lower than
those at the pottery factories. At the time the selection was
made, there was some concern that the concentrations of
lead at the trailer park might be too low because they did
not exceed 400 mg/kg, the residential preliminary
remediation goal (PRG) for lead established by EPA (EPA
2000). However, previous field sampling conducted by
OEPA with XRF analyzers had indicated that total concen-
trations of lead in the soil at the trailer park were well above
400 mg/kg.
2.2 Demonstration Activities
Section 2.2.1 discusses demonstration activities that were
conducted before treatment. Sections 2.2.2 and 2.2.3, re-
spectively, provide detailed descriptions of the demonstra-
tion activities that were conducted during and after the
demonstration.
2.2.1 A ctivities Before Treatment
SITE personnel identified a total of 10 experimental units
at the trailer park, and only one experimental unit at the
inactive pottery factory. All the experimental units were
identified through application of the provisions of a judg-
mental plan based on knowledge of the site and total lead
measurements taken with a field XRF.
SITE Program personnel removed the vegetation (sod)
from the experimental units.To facilitate the homogeniza-
tion of the soil and the collection of samples, the soil in the
ten experimental units at the trailer park was mixed with a
garden tiller to a depth of approximately 6 inches. The soil
in the one experimental unit at the inactive pottery factory
was homogenized by mixing soil with a backhoe to a depth
of 6 inches. The 10 experimental units in the trailer park
were assigned letters (C,G,K,L,M,N,O,Q,R,T), as was the
experimental unit adjacent to the inactive pottery factory
(U). Each of the 10 units in the trailer park measured 5 feet
wide by 5 feet long, and the single unit at the inactive pot-
tery factory unit measured 3 feet wide by 6 feet long. The
depth of the demonstration in all units was limited to the
upper 6 inches of soil. Figure 2-1 shows the locations of
the experimental units at the trailer park, and Figure 2-2
shows the location of the experimental unit at the inactive
pottery factory.
To establish the conditions present before the application
of Envirobond™, soil samples were collected from each
experimental unit. However, the samples were collected
differently at the two locations. At the trailer park, compos-
ite samples were collected from each of the 10 experimen-
tal units; at the inactive pottery factory, five grab samples
were collected from the single experimental unit. Specific
sampling procedures are described below for the trailer
park and the inactive pottery factory.
-------
Table 2-1. Summary of Maximum Concentrations of Lead Observed During Predemonstration
Sampling Activities
Site Name and Location
Trailer Park, Roseville,
Ohio2
Inactive Pottery Factory,
Roseville, Ohio2
Active Pottery Factory,
Roseville, Ohio
Inactive Pottery Factory,
Crooksville, Ohio
Maximum Lead Concentrations1
Total
Field
(mg/kg)
300
23,100
14,500
2,654
Total
Laboratory
(mg/kg)
134
8,170
1,080
793
Leachable
via TCLP
(mg/L)
32.0
48.6
57.9
77.1
Leachable
via SPLP
(mg/L)
<0.50
O.50
<0.50
O.50
Bioaccessible
via SIVM (%)
47
31
42
76
1The results reported represent the maximum concentrations detected, rather than a single sample
from any one location. Total lead measurements in the field were made with XRF analyzers; total
lead measurements in the laboratory were made by nitric acid digestion (SW-846 3050B). TCLP
= toxicity characteristic leaching procedure; SPLP = synthetic precipitation leaching procedure;
SIVM= simplified in-vitro method).
2The trailer park and the inactive pottery factory, both located in Roseville, Ohio, were selected for
the SITE demonstration.
The composite soil samples for each experimental unit at
the trailer park were prepared by collecting an aliquot of
soil from each corner and from the middle of the experi-
mental unit, as Figure 2-1 shows. Each aliquot was placed
in a stainless-steel bowl (approximate volume: 64 ounces)
with a stainless steel spoon ortrowel.The technology was
not to be evaluated for its ability to treat pottery chips;
therefore, the soil samples were screened through a brass
3/8-inch sieve into a plastic 5-gallon bucket to remove pot-
tery chips from the samples. Particles larger than 3/8 inch
were returned to the stainless steel bowl, and the percent-
age of the particles, on the basis of volume, that did not
pass through the sieve was estimated and recorded in the
logbook. The composite sample was hand-mixed in the
bucket with a stainless-steel spoon for one minute before
the sample containers were filled. After mixing, fractions
for the various analyses were prepared by filling the
sample containers with the composited soil. Field duplicate
samples were collected from two of the experimental units
at the trailer park. The five grab soil samples collected from
the single experimental unit at the inactive pottery factory
were collected before treatment from each corner and the
from middle of the experimental unit, as shown in the in-
set diagram on Figure 2-2. Each grab soil sample was
placed in a separate stainless-steel bowl (approximate
volume: 64 ounces) with a stainless-steel spoon ortrowel.
The grab soil sample was sieved through a brass 3/8-inch
sieve into a plastic 5-gallon bucket. Particles largerthan 3/
8 inch were returned to the stainless steel bowl, and the
percentage of the particles, on the basis of volume, that
did not pass through the sieve was estimated and recorded
in the logbook. Each grab sample was hand-mixed in the
bucket with a stainless-steel spoon for one minute before
the sample containers were filled.The grab samples from
various locations were not composited. One field duplicate
sample was collected from one of the grab soil samples
in one of the sampling buckets.
2.2.2 Treatment Activities
RMRS applied the Envirobond™ process after the pre-
treatment activities were completed at each experimental
unit. The Envirobond™ process powder was applied to the
surface of the experimental unit using a fertilizer drop
spreader. The Envirobond™ process liquid was applied
over the powder using a watering can. The Envirobond™
process powder and liquid were mixed into the soil using
a garden tiller. Flyash was used to adjust the soil pH of
each experimental unit to approximately 7.0. A thin layer
was distributed over the surface of the experimental unit
and tilled into the experimental unit.
2.2.3 A ctivities A fter Treatment
SITE personnel evaluated the effectiveness of the treat-
ment by collecting and analyzing soil samples after the
technology was applied and comparing the data from
those samples with the data on the untreated soil. Soil
samples were collected from the experimental units
treated with Envirobond™ after a minimum of 24 hours
after treatment. Sampling of treated soils at the trailer park
consisted of collecting and compositing five soil aliquots
from each experimental unit in the same manner in which
the samples of untreated soil were collected. At the inac-
tive pottery factory, grab samples of treated soils were
collected from the single experimental unit in the same
manner in which the samples of untreated soil were col-
8
-------
LEGEND
Experimental Unit and
Designation
Trailer
r1
CO
a
«
/
'
-
Sampling Locations Within Units
Untreated and Treated Soil
5 feet
0 50 100
Graphic Scale (ft)
5 feet
CRPAC:
Envirobond^Demonstration
FIGURE 2-1
Trailer Park Sampling Locations and Patterns
Tetra Tech EM Inc.
Figure 2-1. Trailer park sampling locations and patterns.
-------
N
t
Inactive Pouery Factory Building
148 feet I2gfeei
II
. . .
rr ' '
Experimental
UnitV
0 f
1 3 feei
6feet I
r,,.r
i • • f Hail line
l.....i.^.-i..^,.i
(not to scale)
Pretreaunent Grab Sampling Locations
• •
•
•3 •<-
Expertmentai Utut V
Post-treatment Grab Sampling Locations
Experiroenta] Unit V
; O
Legend
Experimental Unit V
Sampling location
Downspoui location
Figure 2-2. Inactive pottery factory sampling locations and patterns.
CRPAC
Enviroboad*" Demonsnation
FIGURE 2-2
Inaciive Po«er>' Factory
Sampling Locations and Patterns
Tetra Tech EM Inc.
10
-------
lected, except that nine grab samples were collected in-
stead of five (see Figure 2-2) to obtain a more precise
estimate of the treated sample mean.
2.3 Laboratory Analytical and Statistical
Methods
The SITE program samples collected during the demon-
stration were analyzed by methods described in the QAPP
approved by EPA (TetraTech EM Inc. [TetraTech] 1998).
Statistical analyses were performed on selected analyti-
cal data to demonstrate whetherthe criteria set forth in the
primary and secondary objectives were met. The follow-
ing section presents a brief description of the analytical
procedures and statistical methods used to evaluate the
samples that were collected during the demonstration.
2.3.1 Laboratory Analytical Methods
Several analytical methods were used to evaluate the
project objectives on the basis of the specific analyses of
interest and the minimum detectable concentrations
needed to achieve the project objectives. Whenever pos-
sible, methods approved by EPA were selected to analyze
the soil samples collected during the demonstration.The
following references were used in performing the standard
analytical procedures approved by EPA:
EPA. 1996. Test Methods lor Evaluating Solid Waste,
Physical/Chemical Methods, Laboratory Manual,
Volume 1A through 1C and Field Manual, Volume 2,
SW-846, Third Edition, Update III. EPA Document
Control No 955-001-00000-1. Office of Solid Waste
Washington, DC December. (For convenience, ana-
lytical methods from this reference are referred to as
SW-846, followed by their respective analytical
method number.)
EPA. 1983. Methods for Chemical Analysis of Wa-
ter and Wastes, EPA-600/4-79-020 and subsequent
EPA-600/4-technical additions. Environmental Moni-
toring and Support Laboratory, Cincinnati, Ohio. (For
convenience, analytical methods from this reference
are referred to as MCAWWfollowed by their respec-
tive analytical method number.)
When standard methods were not available, or when the
standard methods did not meet the project objectives,
other published methods were used to analyze the soil
samples. The nonstandard methods were evaluated and
approved for use by EPA NRMRL before the soil samples
were analyzed. Table 2-2 lists the parameters, matrices,
method references, and method titles for the analytical
laboratory procedures used to evaluate the SITE demon-
stration samples. Brief descriptions of the extraction pro-
cedures, lead analytical procedures, and nonstandard
analytical procedures used in the demonstration are pro-
vided below.
Standard Extraction Procedures
Three standard extraction procedures approved by EPA
were used to analyze soil samples to determine the con-
centrations of lead that will leach under various conditions
- the TCLR the MEP and the SPLP. The TCLP is used to
determine the mobility of contaminants in solids and
multiphase waste; it simulates the initial leaching that a
waste would undergo in a sanitary landfill. The MEP was
designed to simulate both the initial and the subsequent
leaching that a waste would undergo in an improperly de-
signed sanitary landfill, where it would be subjected to pro-
longed exposure to acid precipitation. The SPLP is
designed to simulate the initial leaching that a waste would
undergo if it were disposed of in a monofill, where it would
be subjected to exposure to acid precipitation (EPA 1996).
The multiphase steps in performing the extraction proce-
dures are described below.
The basic steps in performing the extraction procedures
are:
Determine the appropriate solution by reviewing
preliminary analyses of the soil's solid content and
pH of the soil
Prepare the appropriate extraction fluid (consisting
of one or more concentrated acids, depending on
the procedure), diluted with distilled deionized wa-
ter
Place a specified quantity of the soil sample in an
extraction vessel with a predetermined quantity of
extraction flu id
Rotate the vessel at the specified rotations per
minute (rpm) for the appropriate amount of time (18
to 24 hours)
Maintain the temperature as described in the meth-
ods
Separate the material by filtering the content of the
vessel through a glass fiber filter
Analyze the resulting liquid for lead concentrations
of lead by the procedures set forth in SW846 meth-
ods 3050B and 601 OB
Extraction Procedure for Bioaccessible Lead
The extraction procedure for soil lead bioaccessibility is
presented in the SIVM.The steps in the procedure are:
Air dry the soil sample, grind it with a mortar and
pestle, and sieve it with a less than 250 microns (/jm)
sieve
Analyze the sample for total lead using a XRF ana-
lyzer
Add the sample to an aqueous extraction fluid con-
sisting of deionized water, glycine as a buffer, and
concentrated hydrochloric acid
Maintain the sample and extraction fluid at a pH of
1.50, ± 0.05, and tumble both in a water bath at 37°
C for one hour, using a modified TCLP apparatus
11
-------
Table 2-2. Analytical Laboratory Methods
Parameter
TCLP Lead
Soil Lead Bioaccessibility
MEP Lead
Lead Speciation by Scanning
Electron Microscopy
Lead Speciation by Sequential
Soil Serial Extractions
Eh
PH
CEC
Acid Neutralization Capacity
Total Lead using Nitric Acid
Digestion
Oil and Grease
Total Lead
Hydrofluoric Acid Digestion
SPLP Lead
Phosphates
Humic and Fulvic Acid
Soil Classification
Matrix
Soil
Soil
Soil
Soil
Soil
Soil
Soil
Soil
Soil
Soil, Plants, Water, Filters
Soil
Soil
Soil
Soil
Soil
Soil
Method Reference
SW-8461311
SIVM (SBRC 1998)
SW-846 1 320
Standard Operating Procedure
for Metal Speciation
(University of Colorado 1998)
Sequential Extraction
Procedure for the Speciation of
Particulate Trace Metals
(Tessier1979)
SW-846 9045C
SW-846 9045C
Soil Sampling and Methods of
Analysis (Canadian Society of
Soil Science 1993)
Environment Canada Method
No. 7
SW-846 3050B, followed by
SW-846 601 OB
EPA Method 1664
SW-846 3052, followed by
SW-846 601 OB
SW-846 131 2
SW-846 9056
Soil Sampling and Methods of
Analysis (Canadian Society of
Soil Science, 1993)
ASTM D2487-93
Title of Method
Toxicity Characteristic Leaching
Procedure
In Vitro Method for Determination of
Lead and Arsenic Bioaccessibility
Multiple Extraction Procedure
Standard Operating Procedure for
Metal Speciation (Draft)
Sequential Extraction Procedure for
the Speciation of Particulate Trace
Metals
Soil and Waste pH
Soil and Waste pH
Exchangeable Cations and Effective
CEC by the BaCI2 Method
Acid Neutralization Capacity
Acid Digestion of Sediments, Sludges,
and Soils,
Inductively Coupled Plasma-Atomic
Emission Spectrometry (ICP-AES)
Method 1664: N-Hexane Extractable
Material (HEM) and Silica Gel Treated
N-Hexane Extractable Material (SGT-
HEM) by Extraction and Gravimetry
(Oil and Grease and Total Petroleum
Hydrocarbons)
Microwave Assisted Acid Digestion of
Siliceous and Organically Based
Matrices, Inductively Coupled Plasma-
Atomic Emission Spectrometry
Synthetic Precipitation Leaching
Procedure
Determination of Inorganic Anions by
Ion Chromatography
Soil Humus Fractions
Standard Classification of Soils for
Engineering Purposes (Unified Soil
Classification System)
(continued)
12
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Table 2-2. Analytical Laboratory Methods (continued)
Parameter
VOCs
SVOCs
Matrix
Soil
Soil
Method Reference
SW-846 8260 B
SW-846 8270C
Title of Method
Volatile Organic Compounds by Gas
Chromatograph/Mass Spectrometry
Semivolatile Organic Compounds by
Gas Chromatography/Mass
Spectrometry: Capillary Column
Technique
Notes: SW-846 = Test Methods for Evaluating Solid Waste, Volumes IA-IC: Laboratory Manual, Physical/Chemical Methods, and
Volume II: Field Manual, Physical/Chemical Methods, SW-846, Third Edition, Update III.
ASTM = American Society for Testing and Materials.
Collect 15 milliliters (ml) of extract from the extrac-
tion vessel into a 20-cubic-centimeter syringe and
filter through a 0.45-micrometer (/jm) cellulose ac-
etate disk filter into a 15-mL polypropylene centri-
fuge tube
Analyze the filtered extract for lead using ICP-AES
according to SW-846 Method 601 OB.
Table 2-3 summarizes the acids used in extraction fluids
and other operational parameters of the extraction proce-
dures.
Lead Speciation by Scanning Electron Microscopy
The percent frequency of various lead species (hereafter
referred to as lead phases) in soil samples before and af-
ter treatment was determined by application of the metal
speciation procedure developed by Dr. John Drexler (Uni-
versity of Colorado 1998).The procedure uses an electron
microprobe (EMP) technique to determine the frequency
of occurrence of metal-bearing phases in soil samples.
The EMP used forth is analysis is equipped with fourwave-
length dispersive spectrometers (WDS), an energy disper-
sive spectrometer (EDS), a backscatter electron imaging
(BEI) detector for taking photomicrographs, and a data
processing system. Two of the spectrometers were
equipped with synthetic "pseudocrystals" that have been
developed recently for WDS applications. The
pseudocrystals are known as layered dispersive elements
(IDE). The materials are composed of alternating layers
of boron and molybdenum of varying thicknesses and are
designed to optimize the separation of individual wave-
lengths in the x-ray characteristic radiation spectrum.The
first of the materials to be produced for WDS applications
(LDE-1) was used in one of the spectrometers for the de-
termination of oxygen. Another spectrometer was
equipped with a IDE designed to detect carbon (LDE-C).
Lead speciation was determined by using the EMP to per-
form point counts on the samples. Point counting is a
method of determining the volume fractions of constituent
phases in a sample from the relative areas, as measured
on a planar surface. The EMP analyzes a sample on a
point-by-point basis to determine how much of a given
phase is present in a sample. The point counts were per-
formed by crossing each sample from left to right and from
top to bottom with the electron beam. The amount of ver-
tical movement for crossing depends on the magnification
used and the size of the cathode-ray tube. In all cases, the
movement was kept to a minimum so that no portion of the
sample was missed.Two magnification settings were used
for each sample, one ranging from 40 to 100 X and the
other ranging from 300 to 600 X.The second magnifica-
tion allowed the identification of the smallest identifiable
phases (1 to 2/jm). The precision of the EMP lead specia-
tion data was determined from duplicate analysis per-
formed every 20 samples.
Lead Speciation by Sequential Extractions
The lead phases in the soil samples from both sites were
identified by application of Tessier's sequential extraction
procedure (Tessier 1979).The soil samples were analyzed
by the Laboratory for Environmental and Geological Stud-
ies at the University of Colorado, Boulder.
The soil samples were air-dried, ground with a mortar and
pestle, and sieved to less than 250 /jm. The procedure
uses sequential chemical extractions with different re-
agents to determine the concentration of lead that parti-
tions into each of several discrete metal phases. The
phases include exchangeable lead, lead bound to carbon-
ates, lead bound to iron oxide, lead bound to manganese
oxide, lead bound to organic matter, and residual lead.
Approximately one gram of the sample aliquot (dried
weight) was used forthe initial extraction.The reagent used
to extract the exchangeable lead phase was magnesium
chloride (MgCI2) at a pH of 7.0. Forthe second extraction,
a solution of sodium acetate and acetic acid at a pH of 5.0
was used to extract the lead bound to carbonates. Forthe
third extraction, a hydroxyl amine hydrochloride in 25 per-
cent acetic acid (pH ~ 2) solution was used to extract the
lead bound to iron and manganese oxides. Forthe fourth
extraction, hot hydrogen peroxide in a nitric acid solution
and subsequently ammonium acetate were used to extract
the lead bound to organic matter. Forthe final extraction,
a solution of hydrofluoric and perchloric acid solution was
13
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Table 2-3. Summary of Extraction Procedures
Method
TCLP
MEP (first extract)
MEP (second through
ninth extracts)
SPLP
SIVM
Extraction Fluid
Acetic acid
Acetic acid
Sulfuric and nitric acids
Sulfuric and nitric acids
Hycrochloric acid
pH of Fluid
4.93 ± 0.05
5.0 ± 0.2
3.0 ± 0.2
4.20 ± 0.05
1 .50 ± 0.05
Temperature
23°C ± 2°C
20°C - 40°C
20°C - 40°C
23°C ± 2°C
37°C
Time of Extraction
18 ± 2 hours
24 hours
24 hours
18 ± 2 hours
1 hour
used to extract the lead bound to primary and secondary
minerals (the residual phase).
Oxidation-Reduction Potential
The soil samples were prepared for determining Eh using
the sample preparation procedures set forth in SW-846
Method 9045C.The method consisted of preparation of a
soil suspension by adding 20 ml of reagent water to 20
grams of soil.The mixture was covered and stirred forfive
minutes. The soil suspension was allowed to stand for one
hour to allow most of the suspended clay to settle out of
the suspension.The Eh then was measured according to
American Society for Testing and Materials (ASTM) Test
Method D1498-93, "Standard Practice for Oxidation-Re-
duction Potential of Water." A meter capable of reading
millivolts (mV) with a reference electrode and an oxidation-
reduction electrode was used to take the measurements.
The meter first was allowed to warm up for two to three
hours before measurements were taken. After the meter
was checked for sensitivity and the electrodes were
washed with deionized water, the electrodes were placed
into the sample. While the sample was agitated with a
magnetic stir bar, successive portions of the sample were
measured until two successive portions differed by no
more than 10 mV.
PH
The pH was evaluated by application of the procedures set
forth in SW846 Method 9045C.The method consisted of
the preparation of a soil suspension by adding 20 ml of
reagent waterto 20 grams of soil.The mixture was covered
and stirred for five minutes. The soil suspension was al-
lowed to stand for one hourto allow most of the suspended
clay to settle out of the suspension. A pH meter was al-
lowed to warm up fortwo to three hours before measure-
ments were taken. After the meter was checked for
sensitivity and the electrodes were washed with deionized
water, the electrodes were placed in the clear supernatant
portion of the sample. If the temperature of the sample dif-
fered by more than 2°C from that of the buffer solution, the
pH values measured were corrected for the temperature
difference.
Cation Exchange Capacity
One sample from the untreated and treated soil samples
from each site was selected for evaluation of CEC, which
was determined by the barium chloride (BaCI2) method.
The BaCI2 method provides a rapid means of determining
the exchangeable cations and the "effective" CEC of a wide
range of soil types. By that method, CEC is calculated as
the sum of exchangeable cations (Ca, Mg, K, Na, Al, Fe,
and Mn).The procedure consisted of the following steps:
The soil sample was air-dried, ground using a mor-
tar and pestle, and sieved to less than 250 /jm
Approximately 0.5 gram of soil was placed into a 50-
ml_ centrifuge tube with 30.0 ml of 0.1 molar BaCI2
and the mixture was shaken slowly on an end-over-
end shaker at 15 rpm for 2 hours
The mixture was centrifuged for 15 minutes, and the
supernatant portion was filtered through a Whatman
No. 41 filter paper
The cations were analyzed with an atomic absorp-
tion spectrophotometer.
Acid Neutralization Capacity
The acid neutralization capacity of the soil was determined
by application of Environment Canada Method No. 7. The
soil sample was air-dried, ground using a mortar and
pestle, and sieved to less than 250 /jm. The amount of
neutralizing bases, including carbonates, was then deter-
mined by treating each sample with a known excess of
standardized hydrochloric acid.The sample and acid were
heated to allow completion of the reaction between the acid
reagent and the neutralizers in the soil sample. The cal-
cium carbonate equivalent of the sample was obtained by
determining the amount of unconsumed acid by titration
with standardized sodium hydroxide.
Lead Analytical Procedures
Two procedures were used to determine the lead concen-
trations in the soil. One analytical procedure used a nitric
acid solution to measure all but the most stable forms of
lead in the sample, and the other procedure used hydrof-
luoric acid to measure all of the lead in the sample. The
nitric acid digestion procedure involved digesting approxi-
mately one gram of soil with a solution of nitric acid, hydro-
14
-------
gen peroxide, and hydrochloric acid. The mixture was
heated to 95°C, ± 5°C, for approximately two hours. The
digestate was filtered through Whatman No. 41 filter paper
into a flask and analyzed for lead ICP-AES, as described
in SW-846 Method 601 OB.
The hydrofluoric acid digestion procedure involved heat-
ing approximately one gram of soil in a solution contain-
ing nitric and hydrofluoric acids to 180°C, ± 5°C, for
approximately 9.5 minutes. The digestate was filtered
through Whatman No. 41 filter paper into a flask, and the
filtrate was analyzed for lead by ICP-AES, as described in
SW846 Method 601 OB.
Soil Classification
Soil classification consisted of determining the particle size
distribution, liquid limit, and plasticity index of the soil
samples. That information was used to classify the soil
according to basic soil group, assigning a group symbol
and name. The particle size distribution was determined
by sieving the dried soil samples through a series of sieves
and determining the percentage by weight that was re-
tained on the sieves. The liquid limit is the water content
(measured as percent moisture) at which a trapezoidal
groove cut in moist soil (in a special cup) closes being
tapped 25 times on a hard rubber plate. The plastic limit is
the water content at which the soil breaks apart when
rolled by hand into threads of 1/8-inch diameter.The plas-
ticity index is determined by first determining the liquid and
plastic limits and then subtracting the plastic limit from the
liquid limit.
Humicand Fulvic Acids
Humic and fulvic acids were extracted from the soil
samples and quantified through the use of a sodium hy-
droxide solution, as described below:
Air dry 15 g of soil, grind it to less than 250 Fm, and
place it in a 250-mL plastic centrifuge bottle
Add 150 ml of 0.5 molar hydrochloric acid, let the
mixture sit for one hour, and then centrifuge it for 15
minutes and discard the supernatant portion
Add 150 ml of deionized water to the centrifuge
bottle and mix it to wash the soil of remaining acid;
centrifuge again for 15 minutes and discard the su-
pernatant portion
Add 150 ml of 0.5 molar sodium hydroxide to the
centrifuge bottle and flush the head space with oxy-
gen-free nitrogen gas
Place the bottle on an end-over-end shaker for 18
hours
Centrifuge the mixture for 15 minutes, decant the
supernatant portion, and separate that portion into
the humic and fulvic fractions by acidifying the ex-
tract to a pH of 1.5; the precipitate is the humic acid
fraction, and the supernatant portion is the fulvic
acid fraction
2.3.2 Statistical Methods
This section provides a brief overview of the statistical
methods that were used to evaluate the data from the SITE
demonstration.The methods included assessing the dis-
tribution of sample data and calculating specific paramet-
ric and distribution-free statistics.
2.3.2.1 Determination of the Distributions of the
Sample Data
A preliminary assessment of distribution of data was con-
ducted to determine the approximate statistical distribution
of the sample data when parametric hypothesis tests were
performed. Forthe evaluation of the data collected forthe
primary and secondary objectives, sample data distribu-
tions were determined by the following methods: (1) com-
mon graphical procedures, including histograms,
box-plots, stem-and-leaf plots, and quartile-quartile plots,
and (2) formal testing procedures, such as the Shapiro-
Wilk test statistic, to determine whether a given data set
exhibits a normal distribution.
2.3.2.2 Parametric and Distribution-free Test
Statistics
Various testing procedures were employed to determine
whether there were any significant differences between
concentrations of lead and concentrations of other
analytes of interest in the treated soil and the untreated
soil.Table 2-4 summarizes the statistical procedures used
in evaluating the analytical results associated with each of
the objectives of the SITE demonstration. As the table
shows, all the parametric statistical procedures used to
evaluate the data from the demonstration involved the
Student's t-tests. Paired Student t-tests were conducted on
data collected from the trailer park, and unpaired Student
t-tests were required on data from the pottery factory be-
cause of the unequal sizes of samples of treated and un-
treated soils from that location (see Figure 2-2). In addition,
the formula forthe Student's t-test was adjusted for evalu-
ation of P2, because the estimator used for that objective
(percent reduction of percent bioavailable lead) required
manipulation to avoid the creation of a cauchy (nonnormal)
distribution, which cannot be evaluated by a Student's t-
test. Data points obtained from the trailer park for evalua-
tion of P2 (sufficient data from the pottery factory were not
available for application of a meaningful Student's t-test for
evaluation of P2) were evaluated in a paired Student's t-
tests, using the following formula:
Yi
S
1=1
(2-1)
1=1
15
-------
Table 2-4. Summary of Statistical Procedures Used to Evaluate Each of the Objectives of the Demonstration
Objective
P1: Determine whether leachable lead in
soil can be reduced to concentrations that
comply with the alternative UTS for
contaminated soil that are codified at 40
CFR part268.491.
P2: Determine whether the portion of total
lead in soil that is "bioaccessible," as
measured by an experimental method, can
be reduced by at least 25 percent2.
S1: Evaluate the long-term chemical
stability of the treated soil.
Test Method/ Test Variable
TCLP/Mean concentration of lead in extract
(mg/L)
SIVM/Mean percentage of total lead
extracted by the method
MEP/Mean lead concentration in each
extract (mg/L)
SEM lead speciation/Percent distribution of
lead among various lead phases3
Sequential extraction/Mean concentration of
lead in each phase (mg/L)
Eh (mV)
PH
CEC/Milliequivalents per gram (meq/g)
Acid neutralization capacity/meq/g
Total lead-nitric acid/Mean lead
concentration of lead (mg/kg)
Statistical Method/Acceptance Criterion for
Meeting the Objective
Student's t-test formula at the 0.05 level of
significance/Mean concentration of the
treated soil must be less than 7.5 mg/L or
90 percent of the mean concentration in
untreated soil, whichever is the higher
value.
Student's t-test formula at the 0.05 level of
significance/Mean percentage of total lead
in the extract from the treated soil must be
at least 25 percent lower than the mean
percentage of total lead in the extract from
the untreated soil.
Review of test results/Concentrations of all
extracts from the treated soils must be lower
than 5 mg/L (a nominal concentration that
would be expected to meet or exceed
cleanup goals at some sites).
Review of test results/Percent frequencies
of more soluble and less soluble phases of
lead in the treated and untreated soils must
be lower and higher, respectively.
Student's t-test formula at the 0.05 level of
significance/Mean concentrations of the
more soluble and less soluble phases of
lead in the treated and untreated soils must
be lower and higher, respectively.
Student's t-test formula at the 0.05 level of
significance/Mean Eh of the treated soil
must be lower than that of the untreated
soil.
Student's t-test formula at the 0.05 level of
significance/Mean pH of the treated soil
must be higher than that of the untreated
soil and 7.0.
Review of test results/CEC must be
increased, as indicated by a qualitative
review of statistical summary data.
Review of test results/Neutralization
capacity must be increased, as indicated by
a qualitative review of statistical summary
data.
Student's t-test formula at the 0.05 level of
significance/Mean concentration of lead in
the treated soil must be lower than that in
the untreated soil.
(continued)
16
-------
Table 2-4. Summary of Statistical Procedures Used to Evaluate Each of the Objectives of the Demonstration (continued)
Objective
S2: Demonstrate that the application of
Envirobond™ did not increase the public
health risk of exposure to lead.
S3: Document baseline geophysical and
chemical conditions in the soil before the
application of Envirobond™.
S4: Document operating and design
parameters for Envirobond™.
Test Method/ Test Variable
Total lead-hydrofluoric acid /Mean
concentration of lead (mg/kg)
SPLP lead/Mean concentration of lead in
the extract (mg/L)
Total phosphate/Mean concentration of
phosphate
SPLP phosphate/Mean concentration of
phosphate in the extract (mg/L)
Total lead/Mean concentration of lead in the
air (mg/m3)
Soil classification, total VOCs, SVOCs, oil
and grease, and humic and fulvic acids
Cost analyses
Statistical Method/Acceptance Criterion for
Meeting the Objective
Student's t-test formula at the 0.05 level of
significance/Mean concentration of lead in
the treated soil must not be higher or lower
than that in the untreated soil.
Student's t-test formula at the 0.05 level of
significance/Mean concentration of lead in
the extract of the treated soil must be less
than 5 mg/L (a nominal concentration that
would be expected to meet or exceed
cleanup goals at some sites).
Review the results/Mean concentration of
total phosphates in the treated soil must not
be significantly higher or lower less than
that in the untreated soil.
Review the results/Mean concentration of
phosphate in the extract of the treated soil
must be less than or equal to that of the
untreated soil.
Review of test results/Concentrations of
airborne lead must not exceed NAAQS
limits for lead.
Review of test results/Identify results that
appear unusual in light of the location and
history of the site (no specific acceptance
criteria were established for S3).
Present cost data/No specific acceptance
criteria were established for S4.
'Objective P1 was evaluated statistically only on analytical results from the inactive pottery factory; only three samples pertinent to that
objective were collected from the trailer park.
Achievement of P2 was evaluated only at the trailer park.
3SEM lead speciation was conducted only on soils collected from the trailer park.
where xti and xul represent the ith observations about
treated and untreated soils, n represents the sample size,
y; represents the calculated difference between the ith ob-
servations, ym represents the arithmetic mean of the cal-
culated differences, and Sy2 represents the calculated
variance.
The calculation results in the following t-test statistic:
t =
ym
n
(2-2)
which follows a t-distribution with n-1 degrees of freedom.
The test then can be used to determine whether the ob-
served mean difference varies significantly from 0.
The formula used for testing fora 100(1-r0) percent reduc-
tion in the arithmetic mean contaminant levels between
normally distributed (paired) data on treated and untreated
soils for P2 was:
CR = CT- Cv(\ -ro) where CT
(2-3)
i=\
i=\
where xth and xuh represent the ith observations about the
treated and untreated soils, n represents the sample size,
CT and Cu represent the arithmetic mean of observations
about the treated and untreated soils, rg represents the
proportionality reduction factor (for example, if testing for
a 25 percent reduction, rg = 0.25), and CR represents the
computed test statistic.The variance forthe estimate was
calculated as follows:
(2-4)
where S72 and S02 represent the calculated sample vari-
ance forthe treated and untreated soils, SUT represents the
calculated sample covariance between the soils, and the
17
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term Var() symbolizes "the variance of." However, the fol-
lowing more convenient calculation was applied to the in-
dividual, paired observations:
y, =
n and
i=\
where all terms are defined as before, since it can be easily
shown that:
ym=CRandSy2 = Var(CR\ (2-6)
That calculation resulted in the following t-test statistic:
t =
(2-7)
which follows a t-distribution with n-1 degrees of freedom.
Bootstrap resampling analysis, a distribution-free analysis,
was performed when assumptions about the distribution
of the sample data were not met. Bootstrap resampling
was used to estimate means, confidence intervals, or con-
struct hypothesis tests. Bootstrap resampling techniques
also were used to check the results produced by various
parametric tests. A bootstrap analysis was performed on
the soil lead bioaccessibility data on the paired samples.
The bootstrap analysis was performed by drawing N
samples of size n from the observed individual percent
reduction (PR) sample values defined as:
' -$L\ (2-8)
where xtfand xu/once again represent the ith observations
about treated and untreated soils, n represents the sample
size, and N represents the number of times the simulations
were performed (A/= 1000 and n = 10 for this study). The
bootstrap samples then were used to calculate: (1) the
observed mean percent reduction; (2) a 100(1-oc)% confi-
dence interval forthis mean estimate, using the observed
bootstrap cumulative distribution function; and (3) the pro-
portion of sample means that exceed a given 100(1-^%
threshold (that calculation represents a bootstrap version
of a hypothesis test).
2.4 Results of the SITE Demonstration
The following sections present the analytical data relevant
to each objective of the demonstration and the results of
evaluations of those data, including summaries of statis-
tical calculations. Section 2.4.1 addresses P1, Section
2.4.2 addresses P2, and sections 2.4.3 through 2.4.6 ad-
dress S1 through S4, respectively.
2.4.1 Evaluation ofP1
Determine whether leachable lead in soil can be reduced
to concentrations that comply with the alternative UTS for
contaminated soil that are codified at 40 CFR part 268.49.
The treatment standards for contaminated soil that are
codified at 40 CFR part 268.49 require that the concentra-
tions of lead in the treated soil, as measured by the TCLP,
must be less than 7.5 mg/L or at least 90 percent lower
than those in the untreated soil, whichever is the higher
concentration. Soil samples were collected from the ex-
perimental unit at the inactive pottery factory before and
after treatment to assess the Envirobond™ treatment pro-
cess. Table 2-5 summarizes the TCLP lead data for the
inactive pottery factory site.
The results of the statistical analysis of those data, shown
in Table 2-6, demonstrate that the mean concentration of
TCLP lead in treated soil from the inactive pottery factory
was significantly less than 7.5 mg/L; in fact, the results
reflect a probability of less than 0.001 (or 1 in 1,000) that
the actual mean concentration of TCLP lead in the treated
soils is higherthan 7.5 mg/L. Therefore, it was concluded
that Envirobond™ acheived the first primary objective (P1)
of the SITE demonstration. In addition, Envirobond™ ex-
ceeded P1 in that the mean concentration of TCLP lead
in the untreated soil was reduced by more than 99 percent.
Data from the trailer park were not used to evaluate P1
because TCLP lead concentrations in all of the treated and
untreated soil samples from this location were either at or
only slightly higher than the detection limit of 0.05 mg/L.
2.4.2 Evaluation ofP2
Determine whether the portion of total lead in soil that is
"bioaccessible,"as measured by an experimental method,
can be reduced by at least 25 percent.
The objective was evaluated by collecting samples of un-
treated and treated soil from the trailer park for soil lead
bioaccessibility and analyzing the samples by the SBRC's
SIVM.Table 2-7 presents the results of the SIVM analysis
of the untreated and treated soil samples. Soil lead
bioaccessibility is the ratio of the amounts of lead that is
solubilized during the extraction to the total amount of lead
in the soil sample. The concentrations of bioaccessible
lead in the untreated soils (mg/kg) are calculated on the
basis of total lead measured in the extract and the mass
of the soil extracted during the test. The concentrations
then are divided by the total concentration of lead mea-
sured in the untreated soil to arrive at the percentage of
bioaccessible lead in the untreated soils. Identical mea-
surements and calculations are used to calculate the per-
centage of bioaccessible lead in the treated soils.
Data analysis for the objective consisted of performance
of an assessment of data distribution and a parametric test
(t-test). An assessment of the results of the validity of the
parametric test was performed by the conduct of a distri-
bution free test (bootstrap analysis).
18
-------
Table 2-5. TCLP Lead Results for the Inactive Pottery Factory Site
Experimental Unit
V
V
V
V
V
V
V
V
V
Sampling Location
1
2
3
4
5
6
7
8
9
Untreated (mg/L)
421
563
320
247
358
n/s
n/s
n/s
n/s
Treated (mg/L)
2.0
1.5
1.4
<0.50
1.5
2.1
0.94
1.7
1.5
Note: n/s = Not sampled (see Figure 2-2)
Table 2-6. TCLP Lead Summary and Test Statistics for the
Inactive Pottery Factory Site
Untreated
Mean
(mg/L)
381.8
Treated
Mean
(mg/L)
1.41
Percent
Reduction
99.63%
Treated
95% UCL
(mg/L)
1.81
Probability
That the
Actual
Treated
Mean Is
>7.5 mg/L
(Students
t-test)
O.001
Table 2-7. Soil Lead Bioaccessibility Results
Unit
A
B
D
E
F
H
I
J
P
S
Untreated Results
Total
Lead
(mg/kg)
676
380
3066
3371
4508
1889
787
1254
1707
1281
Bioaccessible
Lead (mg/kg)
346.04
191.39
1940.58
2103.89
2649.39
849.37
326.71
594.92
831.88
479.92
Percentage
Lead
Bioaccessibility
51 .2%
50.4%
63.3%
62.4%
58.8%
45.0%
41 .5%
47.4%
48.7%
37.5%
Treated Results
Total Lead
(mg/kg)
432
246
3159
2254
2760
1236
463
826
1127
845
Bioaccessible
Lead (mg/kg)
162.65
82.85
1520.11
1 054.99
1259.02
513.68
257.40
378.68
508.59
326.15
Percentage
Lead
Bioaccessibility
37.7%
33.7%
48.1 %
46.8%
45.6%
41 .6%
55.6%
45.8%
45.1 %
38.6%
Summary
Percent
Reduction
26.4%
33.1 %
24.0%
25.0%
22.4%
7.6%
-33.9%
3.4%
7.4%
-3.0%
19
-------
The assessment of data distribution suggested that the soil
lead bioaccessibility data followed a normal distribution (for
both untreated and treated soils).Therefore, the standard
t-test formula for testing for a 100 (1 -r^% reduction in the
arithmetic mean was used, with rg equal to 0.25.Table 2-8
presents a summary of the parametric test statistics, which
can be used to determine whether a reduction of at least
25 percent in the soil lead bioaccessibility has been
achieved.To conclude that reduction of at least 25 percent
has occurred at a significance level of alpha 0.05, the ob-
served t-score should be less than -1.812. On the basis of
that criterion, the percent reduction achieved appears to
be less than 25 percent.
An assessment of the validity of the results of the paramet-
ric test was performed through the conduct of a bootstrap
analysis of the sample values. Forthe bootstrap analysis,
samples of size 10 were drawn with replacement 1,000
times from the Envirobond™soil lead bioaccessibility data.
Table 2-9 summarizes the results of that analysis.
The calculated percent reduction in soil lead
bioaccessibility was 12.07 percent, with a calculated stan-
dard deviation of 6.07 percent and a 95 percent confidence
interval of-0.4 percent to 22 percent. Only two of the 1,000
bootstrap calculations were found to exceed a percent
reduction value of 25 percent.Therefore, the results ofthe
bootstrap analysis support the results ofthe parametric
test, which indicate that Envirobond™ did not appear to
achieve the goal of at least 25 percent reduction in soil lead
bioaccessibility in soils from the trailer park.
2.4.3 Evaluation of Objective S1
Demonstrate the long-term chemical stability of the treated
soil.
Various analytical procedures that are indicative of long-
term chemical stability were selected for use in evaluating
S1. Forthe demonstration, the long-term chemical stabil-
ity ofthe treated soil was evaluated by comparing the ana-
lytical results for the untreated soil samples with those for
the treated soil samples, using leaching procedures, lead
speciation methods, and other inorganic chemical proce-
dures, including: the MEP, lead speciation by scanning
electron microscopy, lead speciation by the sequential soil
serial extraction procedure, Eh, pH, cation exchange ca-
pacity, acid neutralization capacity, total lead in soil (as
determined by two different methods), leachable lead by
the SPLR total phosphates, and leachable phosphates.
The discussions below describe the analytical methods,
how the methods were used to indicate long-term chemi-
cal stability, and the analytical results for each method.
MEP
The MEP was designed to simulate both the initial and
subsequent leaching that a waste would undergo in a sani-
tary landfill. The criterion established for determining
whetherthe results ofthe MEP demonstrate achievements
of S1 (long-term chemical stability) required that the con-
centrations of lead leached from the treated samples were
less than 5.0 mg/L.The criterion is a nominal concentra-
tion that would be expected to meet or exceed cleanup
goals at some sites; therefore, it is not provided in any fed-
eral laws or regulations. Although the MEP was not de-
signed for use on untreated soils, the demonstration plan
included analysis of untreated soils using the MEP to pro-
vide a basis of comparison with the test results on the
treated soils.
Table 2-10 lists the analytical results forthe MEP.The data
from untreated soil at the trailer park site indicated that the
MEP analytical results were consistently less than 5.0 mg/
L. The data on treated soil from the trailer park site indi-
cated that the MEP analytical results were also consis-
tently less than 5.0 mg/L forthe extraction period.
The untreated soils at the five sampling locations at the
inactive pottery factory site contained greaterthan or equal
to 5.0 mg/L of leachable lead. Figures 2-3 through 2-7 dis-
play the MEP results forthe five untreated samples that
were equal to or greater than 5.0 mg/L with the corre-
sponding results from analysis of treated soil.
The MEP lead concentrations ofthe treated soils at the
inactive pottery factory were reduced below 5.0mg/L ex-
cept forthe result forthe Day 4 extraction from sampling
location 1 (5.1 mg/L). Otherthan this one slightly elevated
result, the MEP analytical results indicate that the
Envirobond™ process is effective in reducing the concen-
tration of lead that will leach under repetitive precipitation
of simulated acid rain conditions. Therefore, the long-term
stability ofthe treated soil appears to have been enhanced
by the addition ofthe Envirobond™ process.
Table 2-8. Parametric Test Statistics Soil
Lead Bioaccessibility Data
Statistic
Value of CR1
Standard deviation
t-score (Ho: CR greater
than or equal to 0)
Level of significance
Data
5.48 %
8.27
2.093
0.9686
1 CR = C, - Cu (1-ro ) (see Section 2.3.2.2)
Table 2-9. Bootstrap Statistical Results for Bioavailable
Lead Difference Data
Statistic
Mean
Standard deviation
95% confidence interval
Number of percent reduction samples > 25%
Data
12.07%
6.07%
(-0.4%, 22%)
2/1 ,000
20
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Table 2-10. MEP Analytical Results
Experi-
mental
Unit
Untreated/
Treated
Initial
Extract
(mg/L)
Day 1
(mg/L)
Day 2
(mg/L)
Day3
(mg/L)
Day 4
(mg/L)
Day 5
(mg/L)
Day 6
(mg/L)
Day 7
(mg/L)
Day8
(mg/L)
Day 9
(mg/L)
Day 101
(mg/L)
Trailer Park
A
A
A
(Duplicate)
A
(Duplicate)
B
B
D
D
E
E
F
F
H
H
I
I
J
J
P
P
S
S
Untreated
Treated
Untreated
Treated
Untreated
Treated
Untreated
Treated
Untreated
Treated
Untreated
Treated
Untreated
Treated
Untreated
Treated
Untreated
Treated
Untreated
Treated
Untreated
Treated
<0.050
0.140
0.220
0.110
<0.050
<0.050
0.190
0.420
0.580
0.400
0.250
0.510
0.180
0.460
<0.050
<0.050
1.400
<0.050
<0.050
0.051
0.065
0.083
<0.050
0.058
0.120
0.073
<0.050
<0.050
0.140
0.330
0.150
0.670
1.030
0.290
0.110
<0.050
<0.050
<0.050
0.550
0.150
<0.050
0.085
0.280
<0.050
<0.050
0.057
0.160
0.063
<0.050
<0.050
0.110
0.400
0.210
0.220
0.160
0.510
0.140
<0.050
<0.050
<0.050
0.160
<0.050
0.090
0.270
0.065
O.050
<0.050
O.050
<0.050
0.140
<0.050
<0.050
0.062
0.400
0.089
0.160
0.095
0.330
0.067
0.051
<0.050
0.110
<0.050
<0.050
<0.050
0.120
<0.050
O.050
<0.050
0.062
<0.050
0.065
<0.050
<0.050
0.058
0.470
0.062
0.190
0.085
0.100
<0.050
0.100
<0.050
<0.050
0.052
<0.050
<0.050
<0.050
<0.050
<0.050
<0.050
<0.050
<0.050
<0.050
<0.050
<0.050
0.210
0.260
0.160
0.310
0.400
<0.050
0.640
<0.050
0.160
O.050
<0.050
<0.050
0.050
<0.050
0.140
<0.050
<0.050
<0.050
<0.050
<0.050
0.055
<0.050
0.550
0.100
0.720
0.210
2.200
<0.050
1.700
<0.050
0.240
O.050
0.200
<0.050
0.390
<0.050
0.420
<0.050
<0.050
<0.050
<0.050
<0.050
<0.050
<0.050
0.210
<0.050
0.340
0.200
0.690
0.067
0.620
<0.050
0.077
<0.050
0.270
<0.050
0.260
<0.050
0.150
<0.050
0.052
<0.050
<0.050
<0.050
0.057
0.052
1.400
<0.050
1.000
0.340
3.200
0.088
1.300
<0.050
0.240
<0.050
0.190
<0.050
0.610
0.069
0.360
<0.050
<0.050
0.058
<0.050
0.089
O.050
<0.050
0.200
0.170
0.490
<0.050
2.000
<0.050
0.490
<0.050
0.310
<0.050
0.250
<0.050
0.150
<0.050
0.210
<0.050
<0.050
<0.050
0.062
0.098
0.056
Note: 1 After the initial daily extract, nine extractions are performed on each of the following nine days; if the lead concentration is
higher in Day 9 than the concentrations in Days 7 or 8, the extractions are repeated until concentrations decrease, or until Day 12.
Results for Day 10 were not recorded if there was no increase in lead concentrations from Days 7 or 8 to Day 9.
(continued)
Lead Speciation by Scanning Electron Microscopy
This procedure used an EMP technique to determine the
frequency of occurrence of 18 lead-bearing phases in soil
samples from the trailer park location only. For the dem-
onstration, the mean of the percent frequency of each lead
phase was evaluated with regard to the effect the change
in that phase will have on the long-term chemical stability
of the treated soil.The long-term chemical stability of a soil
is enhanced if the application of Envirobond™ increased
the frequency of the phases having low solubilities (such
as the lead phosphate phase) and decreased the fre-
quency of the species that are highly soluble (such as the
lead metal oxide phase). Because of the volume of data
generated from the procedure (10 samples for each of 18
metal-bearing phases), the mean of the percent frequency
of each phase was determined to compare the analytical
21
-------
Table 2-10. MEP Analytical Results (continued)
Experi-
mental
Unit
Untreated/
Treated
Initial
Extract
(mg/L)
Day 1
(mg/L)
Day 2
(mg/L)
Day 3
(mg/L)
Day 4
(mg/L)
Day 5
(mg/L)
Day 6
(mg/L)
Day 7
(mg/L)
Day 8
(mg/L)
Day 9
(mg/L)
Day 101
(mg/L)
Inactive Pottery Factory
U Location
1
U Location
1
U Location
2
U Location
2
U Location
3
U Location
3
U Location
4
U Location
4
U Location
5
U Location
5
U Location
6
U Location
7
U Location
8
U Location
9
Untreated
Treated
Untreated
Treated
Untreated
Treated
Untreated
Treated
Untreated
Treated
Treated
Treated
Treated
Treated
390
1.100
420
0.760
220
0.530
21
0.270
130
0.940
0.600
0.390
0.190
0.940
200
0.520
160
0.320
76
0.230
0.230
0.092
16
1.700
1.000
0.800
0.140
0.440
52
1.100
31
0.750
18
0.920
1.500
0.270
1.900
2.600
2.000
0.580
0.110
0.850
0.890
2.600
0.890
1.600
0.210
1.600
0.240
0.640
0.560
1.300
1.400
0.970
0.062
1.200
1.200
5.100
0.390
2.200
0.410
2.300
0.190
0.580
0.360
1.200
0.900
1.300
0.058
3.400
0.570
3.300
0.370
1.500
1.400
2.300
0.280
0.290
15
0.390
0.410
0.310
0.210
2.500
17
0.720
16
0.500
1.300
0.500
1.300
0.550
9
0.900
0.980
0.940
0.550
0.630
16
0.900
20
0.640
0.910
0.790
0.160
0.490
1.700
0.540
0.650
0.800
0.210
1.100
10
1.600
17
1.100
1.400
1.400
0.490
0.870
7.600
0.990
1.400
1.100
1.400
1.300
1.000
1.100
9.5
1.200
0.210
1.100
0.140
0.960
0.250
1.200
1.200
0.990
0.200
1.100
0.640
0.770
0.140
0.960
0.750
0.890
0.850
Note: 1 Afterthe initial daily extract, nine extractions are performed on each of the following nine days; if the lead concentration is
higher in Day 9 than the concentrations in Days 7 or 8, the extractions are repeated until concentrations decrease, or until Day 12.
Results for Day 10 were not recorded if there was no increase in lead concentrations from Days 7 or 8 to Day 9.
results for untreated and treated soils. The unpublished
TER provides a table of the raw lead speciation data. The
TER is available upon request from the EPA work assign-
ment manager (see Section 1.4 for contact information).
Table 2-11 shows the mean percent frequency of each
metal phase for untreated and treated soils, as well as
other descriptive statistics. The data suggest that there
were potentially significant changes from untreated to
treated soils for only 4 of the 18 phases that were evalu-
ated. The frequency of the lead silica phosphate phase
increased between the values for untreated and treated
soils, a condition that would be indicative of an increase
in the long-term chemical stability of the soil. Also indica-
tive of chemical stability are the apparent reduction in the
iron oxide phase of lead. The results also indicate that there
were decreases in the glass and slag phases of lead,
which indicates a reduction in stability from the untreated
to the treated soils. Because of the nature of the specia-
tion test, it is not possible to identify the net result of the
changes in the frequencies of those four phases. There-
fore, the lead speciation results were not unanimously
consistent with the attainment of objective S1; however, it
22
-------
1.100 0.520 1.100 2.600 5.100 3.300 0.720 0.900 1.600 1.100 0.640
Post-treatment
Extraction Day
Figure 2-3 . MEP lead results for inactive pottery factory sampling Location 1.
appears that those results suggest that Envirobond™ can
enhance the long-term stability of treated soil.
Lead Speciation by Sequential Extraction
This procedure uses sequential chemical extractions with
different reagents to determine the concentration of lead
that partitions into each of several discrete metal phases.
The phases include exchangeable lead, lead bound to
carbonates, lead bound to iron oxide, lead bound to man-
ganese oxide, lead bound to organic matter, and residual
lead.
The lead in the exchangeable phase, carbonates phase,
iron oxide phase, manganese oxide phase, and organic
matter phase is subject to release to the environment in a
soluble form because of such changes in soil conditions
as pH and Eh.The residual phase contains principally pri-
mary and secondary minerals that may hold the lead within
their crystal structures.Therefore, long-term stability was
evaluated by comparing the concentrations of lead in each
phase of the untreated samples with the concentrations of
lead in each phase of the treated samples. Long-term sta-
bility would be suggested if there are decreases in the
concentrations of lead in the exchangeable phase, carbon-
ates phase, iron oxide phase, manganese oxide phase,
and organic matter phase, with an increase in the residual
phase.
Tables 2-12 and Table 2-13 present the results of the se-
quential extractions on soil samples from the trailer park
and the inactive pottery factory, respectively. On the basis
of an assessment of graphical data distribution the se-
quential extraction data appearto be distributed normally.
Therefore, the data on untreated soils from the trailer park
and the inactive pottery factory were analyzed separately
through application of a series of individual t-tests extrac-
tion.
Table 2-14 displays the summary statistics associated with
the sequential extraction data from both locations.Those
statistics include the estimated means for the untreated
and treated soils, the calculated percent change in those
means, and the level of significance of each t-score. Note
that, because a total of sixsimultaneous t-tests were per-
formed, a Bonferroni correction was used to preserve the
overall Type 1 error rate. Therefore, no t-score should be
considered statistically significant at the 0.05 level unless
23
-------
160
31
20
18
16
14
12
10
8
6
4
2
0
EP-Tox
Day
'V
Day!
Day 3
Day 4
Day5
Day?
Day 9
Day 10
Pretreatment
420
160
31
0.890
0.390
0.370
16.000
20.000
17.000
9.500
Post-treatment
0.760 0.320 0.750 1.600 2.200 1.500 0.500 0.640 1.100 1.200 0.770
Extraction Day
Figure 2-4. MEP lead results for inactive pottery factory sampling Location 2.
the corresponding level of significance is less than 0.05/6
= 0.0083.
As Table 2-14 shows, the results of the sequential serial
soil extractions indicate significant reductions in the con-
centrations of five of the six lead phases (exchangeable,
carbonate, manganese oxide, iron oxide, and organic
matter) and a significant increase in the residual lead
phase in soils from both sites. Those results are consis-
tent with those obtained for lead speciation by the SEM
procedure (presented in the previous section).
Therefore, the lead speciation results were unanimously
consistent with the attainment of objective S1; and thus it
appears that those results suggest that Envirobond™ can
enhance the long-term stability of treated soil.
Eh
Eh was evaluated to determine whether the treated soil
exhibits an oxidizing or reducing environment. Reducing
conditions favor retention of lead in the soil, which may
increase the long-term stability of the treated soil.The long-
term stability of the treated soil was evaluated by compar-
ing the Eh values for untreated soil with the values for
treated soils and by determining whetherthe soil exhibited
an oxidizing or reducing environment. A decrease in the Eh
values would suggest long-term stability of the treated soil.
Table 2-15 presents the Eh data for untreated and treated
soil from the trailer park, and Table 2-16 presents the Eh
data for untreated and treated soil from the inactive pot-
tery factory. These Eh data appear to be normally distrib-
uted, based on a graphical data distribution assessment.
Table 2-17 presents the summary statistics associated
with the analysis. Included in that table are the observed
Eh means for untreated and treated soils, the estimated
mean differences, and the levels of significance of the cor-
responding t-scores for the soil from the trailer park. The
differences in the Eh mean levels from the untreated to the
treated soil at both locations do not appear to be statisti-
cally significant. Overall, the results suggest that the ap-
plication of Envirobond™ does not increase or decrease
the Eh of the treated soil significantly. Therefore, the results
for Eh did not demonstrate accomplishment of S1; how-
ever, it appears that failure to achieve that objective may
24
-------
zzu
"If
/o
20
10
16
12
10
~
-
-
o-
n Pretreatment
• Post-treatment
E
'N
^
'N
^
P-
L_.
Tox
220
0.530
'N
^
D,
•
lyl
76
0.230
I
u
)a;
' •
• J r-1 11 PL 1 • !""• ~ J
y2 Day 3 Day 4 Day 5 Day 6 Day 7 Day 8 Day 9 Day 10
18 0.210 0.410 1.400 1.300 0.910 1.400 0.210 0.140
0.920 1.600 2.300 2.300 0.500 0.790 1.400 1.100 0.960
Extraction Da}'
Figure 2-5. MEP lead results for inactive pottery factory sampling Location 3.
not reduce significantly the long-term stability of soils
treated with Envirobond™.
PH
In general, the maximum retention of lead is achieved in
soils that are characterized by a pH higher than 7.0, and
the solubility of lead is generally lower in soils that have a
pH between 7.0 and 10.0. Therefore, the pH values of un-
treated and treated soils were evaluated to determine
whether the pH was higher than 7.0 in the samples of
treated soil and to determine whether the pH values had
increased after treatment with Envirobond™.
Table 2-18 presents the analytical results for pH in the soil
from the trailer park. Table 2-19 displays the pH analytical
results for pH in the soil from the inactive pottery factory.
On the basis of an assessment of data distribution, the pH
data appearto be distributed normally; however, pH is the
negative log of hydrogen ion activity. Therefore, pH data on
the untreated and the treated soils were converted to molar
concentration units, and then were analyzed separately for
the trailer park and the inactive pottery factory, through the
use of individual t-tests.
Table 2-20 shows the summary statistics associated with
the analysis. Included in the table are the observed pH
means (calculated using observed pH values after they
were converted to molar concentrations) for untreated and
treated soils, the estimated mean differences, and the lev-
els of significance of corresponding t-scores. Note that the
increase in pH mean levels from untreated to treated soils
at the trailer park appears to be statistically significant.
However, the decrease in pH mean levels from untreated
to treated soils at the inactive pottery factory also appears
to be statistically significant, and none of the pH values for
treated soils from either location are within the optimum
range of 7.0 to 10.0. On the basis of those results, the
application of Envirobond™ does not appear to have en-
hanced the long-term stability of the treated soil.
Cation Exchange Capacity
The objective of the tests for CEC was to determine if
Envirobond™ could increase the CEC, which would indi-
cate an increase in the ability of the soil to prevent migra-
tion of lead. The analytical results for CEC from one
untreated soil sample were compared with those from one
treated soil sample collected at both the trailer park and
the inactive pottery factory to determine whether the cat-
ions in Envirobond™ changed the mobility of the lead in
25
-------
zzu
rif: „
/O
20
lo
lo
t!2 -
ii
10-
6-
4-
2"
o-
n Pretreatment
• Post-treatment
—
—
^~
E
P-
• ' j . ' • '
•
rn i — i '«
„ .-^- II— _• ,-•. ,-ft, 1 M • r^P '- — * IP
Fox Day 1 Day 2 Day 3 Day 4 Day 5 Day 6 Day 7 Day 8 Day 9 Day 10
21.000 0.230 1.500 0.240 0.190 0.280 1.300 0.160 0.490 0.140
0.270 0.092 0.270 0.640 0.580 0.290 0.550 0.490 0.870 0.960 0.750
Extraction Day
Figure 2-6. MEP lead results for inactive pottery factory sampling Location 4.
the soil. Table 2-21 displays the CEC data from the trailer
park, and Table 2-22 displays the CEC data from the inac-
tive pottery factory. The CEC data for the trailer park show
an increase from the result for untreated soil of 0.13 meq/
g to the result for treated soil of 0.75 meq/g. CEC data for
the inactive pottery factory also show an increase in the
CEC from the result for untreated soil of 0.07 meq/g to the
result for treated soil of 0.51 meq/g.
At both sites, the availability of exchangeable potassium
showed the largest increase.The total observed increases
in the available cations would be expected to reduce the
migration rates and the total distances of migration of the
total masses of lead in the soils at both sites. Therefore,
improvements in the CEC indicate that the application of
Envirobond™ appears to have enhanced the long-term
stability of the treated soil. However, the results are not
quantitative because CEC tests were conducted on only
one sample from each site.
Acid Neutralization Capacity
One soil sample was collected before and another afterthe
application of Envirobond ™ at the trailer park and the in-
active pottery factory; all four samples were analyzed for
acid neutralization capacity. Increasing the acid neutraliza-
tion capacity provides more ligands for formation of the
more stable lead complexes, thereby enhancing the long-
term stability of treated soil. Data on acid neutralization
capacity for soil from the trailer park indicate that there was
an increase from the result for untreated soil of 0.0242
meq/g to the result for treated soils of 1.0580 meq/g. The
data on acid neutralization capacity for the inactive pottery
factory indicate that there was a decrease from the data
on the result for untreated soil of 0.6266 meq/g to the re-
sult fortreated soil of 0.4408 meq/g. Because the analyti-
cal results were not consistent at the two sites, the data
do not suggest that the long-term stability of the treated soil
was enhanced by the application of Envirobond™. How-
ever, the results are not statistically conclusive because
only one pair of soil samples was collected at each loca-
tion.
Total Lead in Soil
Two analytical procedures were used to determine total
concentrations of lead in the soil. One procedure, SW-846
Method 3050B, uses a nitric acid solution to digest the lead.
The solution is a very strong acid that dissolves almost all
of lead in a sample that could become "environmentally
available" (EPA 1996); however, the method is not a total
digestion technique. Lead bound in silicates and lead
26
-------
1JU
in
ZU
to
Jo
1 Ł
ID
H.
tii
12
in
1U
f1 Pretreatment
| Post- treatment
••
•
.
•
• 1 • •
I 1 !-• J
n •
b . • _• •
EP-Tox Dayl Day 2 Day 3 Day 4 Day 5 Day 6 Day? Day 8 Day 9 Day 10
130.00 16,000 1,900 0.560 0,360 15.000 9,000 1.700 7.600 0,250
0.940 1,700 2.600 1.300 1.200 0.390 0.900 0,540 0,990 1.200 0890
Extraction Day
Figure 2-7. MEP lead results for inactive pottery factory sampling Location 5.
bound to organics may not be dissolved by this method.
Therefore, a portion of each soil sample was also digested
by hydrofluoric acid. That procedure digests the siliceous
and organic matrices and other complex matrices to pro-
duce a total concentration of lead.
Application of both procedures to determining the concen-
tration of lead was used to ascertain whether Soil Rescue
forms complex matrices that are not dissolved readily.
Binding of the lead into complex matrices should reduce
the concentration of lead that is environmentally available.
If the concentration of lead determined by nitric acid diges-
tion decreases after treatment while the concentration of
lead determined by hydrofluoric acid digestion does not
change significantly, the risk of exposure to environmen-
tally available lead is reduced. If the concentration of lead
determined by nitric acid digestion increases after treat-
ment while the concentration of lead determined by hydrof-
luoric acid digestion does not change significantly, the risk
of exposure to environmentally available lead is increased.
If the concentration of lead determined by both procedures
does not change significantly, the risk of exposure to en-
vironmentally available lead is unchanged. However, if the
concentration of lead determined by hydrofluoric acid di-
gestion increases significantly, the distribution of lead in
complex matrices may follow a non-normal pattern. These
tests were extremely aggressive tests, thus meeting the
acceptance criteria established forthese tests was not as
important as meeting the acceptance criteria of othertests
involving long-term chemical stability.
Table 2-23 lists the concentrations of lead determined by
nitric acid digestion of untreated and treated soil from the
trailer park, and Table 2-24 lists the concentrations of lead
acid digestion of untreated and treated soil from the inac-
tive pottery factory.The data appearto be distributed nor-
mally, as indicated by a graphical assessment of data
distribution.Therefore, the differences between total lead
in treated and untreated soils were analyzed separately for
the trailer park and the inactive pottery factory, through the
use of separate Student t-tests.
Table 2-25 displays the summary statistics associated with
the analysis. The statistics include the estimated untreated
and treated mean concentrations of lead, the calculated
percent change in the means, and the levels of significance
ofthet-scores.The observed mean concentration of lead
in soil from the trailer park decreased from 1,157.9 mg/kg
to 809.5 mg/kg, while the mean concentration of lead in soil
from the inactive pottery factory decreased from 36,140
mg/kg to 30,488.9 mg/kg.The corresponding t-scores in-
dicate that the decrease at the trailer park is statistically
significant, and that the decrease at the inactive pottery
factory is not statistically significant. Therefore, the statis-
tical analysis of the data suggests that, at the trailer park,
Envirobond™ has resulted in binding a portion of the to-
27
-------
Table 2-11. Summary of Percent Frequency of Lead Phases Statistical Data
Phase of Lead
Anglesite
Barite
Brass
Cerussite
Clay
Fe-Oxide2
Fe-Pb Sulfate
Galena
Glass2
Mn-Oxide
Organic
Pb Vanadate
PbMO
PbSiO2
Phosphate
Si-Phosphate2
Slag2
Solder
Untreated
Mean
0.01
0.18
0.48
0.87
0.06
29.55
0.44
0.01
45.74
7.09
1.05
0
2.71
0.26
0.05
0
11.96
0.04
Standard Deviation
nc
.22
nc
nc
nc
23.35
1.14
nc
19.73
nc
nc
nc
3.46
nc
nc
0
11.02
nc
Number of Zero Values
9
4
9
8
9
1
2
9
0
5
8
10
1
7
8
10
1
9
Treated
Mean
0
0.16
0.07
0.04
0
4.34
0.19
0
14.37
0.22
1.68
0
0.31
0.03
2.3
76.95
0
0
Standard Deviation
nc
.3
nc
nc
nc
2.43
0.6
nc
5.55
nc
nc
nc
0.19
nc
nc
5.24
0
nc
Number of Zero Values
10
6
9
9
10
2
1
10
0
5
7
10
0
9
5
0
10
10
1 nc = not calculated. Standard deviations were not calculated for data on lead phases that were associated with five or more zero-
value data points for both the untreated and treated soils.
2 Appears to be a significant difference between treated and untreated soils.
tal lead in such a mannerthat it is no longer subject to di-
gestion using nitric acid (This suggestion, however is not
supported by the results of the hydrofluoric acid digestion
method for total lead; see next section). However there
were no significant differences in mean concentrations of
total lead between untreated and treated soils from the
inactive pottery factory using the nitric acid digestion
method for total lead.
Table 2-26 presents the concentrations of lead determined
by hydrofluoric acid digestion of untreated and treated soil
from the trailer park, and Table 2-27 presents the concen-
trations of lead determined by hydrofluoric acid digestion
of untreated and treated soils from the inactive pottery fac-
tory. The data also appear to be distributed normally, and
the estimates of sample variance for the data from both
locations again appear to be approximately equivalent.
Therefore, separate Student t-tests were performed on the
data from the pottery factory and the data from the trailer
park to compare the differences in total concentrations of
lead in untreated and treated soils.
Table 2-28 displays the summary statistics associated with
the analyses. The statistics again include the estimated
mean concentrations of lead for untreated and treated soil,
the calculated percent change in the means, and the level
of significance of the t-scores.The observed mean concen-
tration of lead in soil from the trailer park decreased from
1,345.7 mg/kg to 666.8 mg/kg, and the mean concentra-
tion of lead in soil from the pottery factory also decreased
from 41,500 mg/kg to 28,633 mg/kg. The change in the
mean concentrations of lead is not statistically significant
at the inactive pottery factory, according to the t-score
value, which is the expected outcome of the analysis. How-
ever, the decrease in total concentrations of lead at the
trailer park is considered significant.Therefore, the statis-
tical analysis of those data suggests that there was no dif-
ference in concentrations of lead between treated and
28
-------
Table 2-12. Sequential Serial Soil Extracts Results from the Trailer Park
Unit
A
B
D
E
F
H
I
J
P
S
Sampling Location
Comp
Comp
Comp
Comp
Comp
Comp
Comp
Comp
Comp
Comp
Untreated
1
5.89
2.86
37.14
31.45
29.26
23.65
10.95
12.17
10.67
11.44
2
5.02
2.37
40.08
60.78
87.24
12.39
8.16
15.21
28.07
12.99
3
2.987
1.445
10.85
18.82
4.182
10.867
1.723
3.158
6.903
1.748
4
4.77
4.11
32.76
32.22
51.90
24.40
6.95
12.76
18.48
12.59
5
6.44
3.16
32.05
25.13
52.20
53.44
7.65
10.69
15.11
7.92
6
228
169
862
554
1182
1698
194
253
684
497
Treated
1
0.48
0.02
1.67
1.25
2.07
0.72
0.22
0.13
0.85
0.68
2
0.15
0.05
2.64
1.57
1.95
1.16
0.31
0.45
0.76
1.07
3
0.018
0.016
1.167
0.319
0.640
0.146
0.067
0.083
0.276
0.02
4
0.51
0.12
2.19
1.66
0.84
0.56
0.76
0.47
0.86
0.66
5
1.62
0.59
17.74
11.13
11.40
3.74
2.75
4.54
3.48
4.02
6
607
307
3128
3004
2941
1620
513
851
1362
1191
Note: 1 = Exchangeable phase (mg/L Pb), 2 = Carbonate phase (mg/L Pb), 3 = Manganese oxide phase (mg/L Pb), 4 = Iron
oxide phase (mg/L Pb), 5 = Organic matter phase (mg/L Pb), 6 = Residual phases ( mg/L Pb).
Table 2-13. Sequential Serial Soil Extracts Results from the Inactive Pottery Factory
Unit
V
V
V
V
V
V
V
V
V
Sampling
Location
1
2
3
4
5
6
7
8
9
Untreated
1
178.40
171.20
135.50
159.20
141.80
n/s
n/s
n/s
n/s
2
1 ,460.6
2,122.7
740.83
791 .60
1 ,003.5
n/s
n/s
n/s
n/s
3
169.60
327.95
155.73
125.60
168.58
n/s
n/s
n/s
n/s
4
657.00
718.20
352.20
362.80
598.20
n/s
n/s
n/s
n/s
5
162.40
158.10
157.70
171.50
185.20
n/s
n/s
n/s
n/s
6
20,948.
14,034.
13,872.
13,273.
20,748.
n/s
n/s
n/s
n/s
Treated
1
41.58
43.74
25.47
31.23
49.64
23.26
54.44
25.21
50.79
2
96.85
45.02
10.95
65.48
57.95
87.32
50.79
109.70
49.93
3
4.81
4.67
5.70
4.03
3.81
4.18
5.77
5.13
2.50
4
98.98
58.88
105.00
56.76
76.69
96.44
51.60
109.20
69.95
5
1 ,084.
565.60
1,056.
726.10
850.40
992.40
766.10
896.30
792.00
6
33,788
25,213
23,931
26,056
27,664
31,917
27,162
27,208
27,071
Note: 1 = Exchangeable phase (mg/L Pb); 2 = Carbonate phase (mg/L Pb); 3 = Manganese oxide phase (mg/L Pb); 4 = Iron oxide phase
(mg/L Pb), 5 = Organic matter phase (mg/L Pb); 6 = Residual phases ( mg/L Pb); n/s = not sampled.
29
-------
Table 2-14. Sequential Serial Soil Extracts: Summary Statistics
Phase
Untreated
Mean
(mg/L Pb)
Treated Mean (mg/L Pb)
Mean Difference (Untreated - Treated)
Significance level
Trailer Park
Exchangeable
Carbonate
Manganese Oxide
Iron Oxide
Organic Matter
Residual
17.55
27.23
6.27
20.09
21.38
632.1
0.81
1.01
0.27
0.86
6.1
1 ,552.4
16.74
26.22
6
19.23
15.28
-920.3
0.00051
0.0071
0.0041
0.001 1
0.0081
0.0051
Inactive Pottery Factory
Exchangeable
Carbonate
Manganese Oxide
Iron Oxide
Organic Matter
Residual
157.26
1223.9
1 89.49
537.8
167
16,575
38.37
74.45
4.51
80.40
858.98
27,779
118.89
1,149.45
184.98
457.4
-691 .98
-1 1 ,204
0.0001 1
0.0051
0.0031
0.0021
0.0001 1
0.00051
1 Significant difference between treated and untreated soil (A significance level of 0.0083 or lower is needed to declare a
significant difference, based on a Bonferroni correction needed to preserve the significance level of 0.05)
Note: Hypothesis associated with significance level is Ho: mean untreated - mean treated = 0.
Table 2-15. Trailer Park Eh Analytical Results
Experimental
Unit
A
B
D
E
F
H
I
J
P
S
Sampling
Location
Composite
Composite
Composite
Composite
Composite
Composite
Composite
Composite
Composite
Composite
Untreated
Eh (mV)
660
560
550
730
640
530
530
580
510
630
Treated
Eh (mV)
560
650
560
560
450
760
1200
810
550
580
30
-------
Table 2-16. Inactive Pottery Factory Eh Analytical Results
Experimental Unit
V
V
V
V
V
V
V
V
V
Sampling Location
1
2
3
4
5
6
7
8
9
Untreated Eh (mV)
610
510
520
530
570
n/s
n/s
n/s
n/s
Treated Eh (mV)
530
530
530
650
550
560
460
630
640
Note: n/s = not sampled.
Table 2-17. Eh Summary Statistics
Statistic
Untreated Mean
(Standard deviation)
Treated Mean
(Standard deviation)
Mean Difference
(Untreated - Treated)
Significance level
Trailer Park Data
(mV)
592 (70.5)
668(215)
76
0.185
Inactive Pottery
Factory Data (mV)
548 (41 .5)
562 (65)
-14
0.3136
Note: Hypothesis associated with significance level is Ho:
mean untreated - mean treated = 0. A paired t-test was
conducted on data from the trailer park, and an unpaired t-test
assuming unequal variances between treated and untreated
samples was conducted on the data from the pottery factory.
Table 2-18. Trailer Park pH Analytical Results
Experimental
Unit
A
B
D
E
F
H
I
J
P
S
Sampling
Location
Composite
Composite
Composite
Composite
Composite
Composite
Composite
Composite
Composite
Composite
Untreated
5.2
5.2
6.1
6.2
7.0
5.8
5.4
6.0
6.0
5.7
Treated
6.6
6.5
6.3
6.4
5.9
6.0
6.9
6.6
6.1
6.2
untreated soils from the inactive pottery factory and a sig-
nificant decrease in mean concentration of lead in treated
soil from the trailer park, as determined by hydrofluoric acid
digestion method.The reason forthe significant decrease
is unknown; however, it is possible that the drop in total lead
concentrations (as measured by the hydrofluoric acid di-
gestion method) at the trailer park may have been the re-
sult of the sampling efforts conducted on the untreated
soils, which may have removed some hot spots of high
lead concentrations that were bound in stable matrices
(therefore, no more of such materials may have remained
when the soils were sampled after the application of
Envirobond™).Therefore, the decrease in lead between
the untreated and treated soils observed in the results of
the nitric acid digestion method at the trailer park also may
be due to the removal of hot spots, rather than the bind-
ing action of Envirobond™.
SPLP Lead
The SPLP concentrations of lead in untreated soil were
compared with the SPLP concentrations of lead in treated
soil to determine whether the application of Envirobond ™
decreased the solubility of the lead in the soil. The crite-
rion selected for determining whether the application of
Envirobond™ had an effect on the soil was a concentra-
tion of SPLP lead in treated soil of less than 5.0 mg/L.
31
-------
Table 2-19. Inactive Pottery Factory pH
Analytical Results
Experimental
Unit
V
V
V
V
V
V
V
V
V
Sampling
Location
1
2
3
4
5
6
7
8
9
Untreated
7.2
7.7
7.7
7.3
7.3
n/s
n/s
n/s
n/s
Treated
5.8
5.7
6.2
4.8
5.8
6.3
4.6
6.3
5.5
Note: n/s = Not sampled
Table 2-20. pH Summary Statistics
Statistic
Untreated Mean1
Treated Mean1
Mean Difference
(Untreated -Treated)
Significance level
Trailer Park
Data
5.62
6.26
0.64
0.018
Inactive Pottery Factory
Data
7.36
5.25
-2.11
0.045
1 . Mean values are reported as pH; however, they were
calculated based on molar concentration units obtained by
conversion of the individual pH unit measurements shown in
tables 2-1 8 and 2-19.
Note: Hypothesis associated with significance level is Ho:
mean untreated - mean treated = 0. A paired t-test was
conducted on data from the trailer park, and an unpaired t-test
assuming unequal variances between treated and untreated
samples was conducted on the data from the pottery factory.
Table 2-21. CEC Analytical Results for Soil from the Trailer Park
Untreated/
Treated
Untreated
Treated
Na
(meq/g)
0.0002
0.6236
Al (meq/g)
0.0004
0.0001
Ca
(meq/g)
0.1083
0.0878
Mg
(meq/g)
0.0185
0.0338
K (meq/g)
0.0038
0.0024
Fe
(meq/g)
0.0001
0.0000
Mn
(meq/g)
0.0005
0.0003
Total
(meq/g)
0.1316
0.7480
Note: meq/g = milliequivalents per gram = weight of element in soil (mg) •*• (atomic weight [g] •*• valence) per gram of
soil.
Table 2-22. CEC Analytical Results for Soil from the Inactive Pottery Factory
Untreated/
Treated
Untreated
Treated
Na
(meq/g)
0.0024
0.2961
Al (meq/g)
0.0001
0.0002
Ca
(meq/g)
0.0606
0.1310
Mg
(meq/g)
0.0064
0.0771
K (meq/g)
0.0003
0.0037
Fe
(meq/g)
0.0000
0.0000
Mn
(meq/g)
0.0000
0.0032
Total
(meq/g)
0.0699
0.5113
Note: meq/g = milliequivalents per gram = weight of element in soil (mg) x •*• (atomic weight [g] •*• valence) per gram of
soil.
32
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Table 2-23. Lead Analytical Results for Nitric Acid
Digestion for Soil from the Trailer Park
Experimental
Unit
A
B
D
E
F
H
1
J
P
S
Sampling
Location
Composite
Composite
Composite
Composite
Composite
Composite
Composite
Composite
Composite
Composite
Untreated
(mg/kg)
399
251
2,230
2,130
2,520
1,130
511
704
1,070
634
Treated
(mg/kg)
506
175
1,900
1,390
1,570
575
307
473
758
441
Table 2-24. Lead Analytical Results for Nitric Acid
Digestion for Soil from the Inactive Pottery Factory
Experimental
Unit
V
V
V
V
V
V
V
V
V
Sampling
Location
1
2
3
4
5
6
7
8
9
Untreated
(mg/kg)
36,600
36,300
22,800
27,500
57,500
n/s
n/s
n/s
n/s
Treated
(mg/kg)
56,500
23,100
26,300
23,200
28,700
27,200
27,800
39,500
22,100
Note: n/s = not sampled.
Table 2-25. Summary Statistics for Nitric Acid Digestion
Statistic
Untreated mean
(Standard deviation)
Treated mean
(Standard deviation)
Mean Difference
(Untreated - Treated)
Level of significance
Trailer Park
Data (mg/kg)
1,157.9(834)
809.5 (592)
348.4
0.003
Inactive Pottery
Factory Data (mg/kg)
36,140.0(13,314)
30,488.9 (1 1 ,038)
5,651.0
0.223
Note: Hypothesis associated with significance level is Ho: mean
untreated - mean treated = 0. A paired t-test was conducted on
data from the trailer park, and an unpaired t-test assuming
unequal variances between treated and untreated samples was
conducted on the data from the pottery factory.
Table 2-26. Trailer Park Lead Analytical Results
Using Hydrofluoric Acid Digestion
Experimental
Unit
A
B
D
E
F
H
I
J
P
S
Sampling
Location
Composite
Composite
Composite
Composite
Composite
Composite
Composite
Composite
Composite
Composite
Untreated
(mg/kg)
214
307
2,770
2,390
2,780
1,230
492
664
1,220
1,390
Treated
(mg/kg)
453
226
522
228
1,950
939
382
508
937
523
33
-------
Table 2-27. Inactive Pottery Factory Lead
Analytical Results Using Hydrofluoric Acid Digestion
Experimental
Unit
V
V
V
V
V
V
V
V
V
Sampling
Location
1
2
3
4
5
6
7
8
9
Untreated
(mg/kg)
54,900
53,200
1 1 ,500
40,900
47,000
n/s
n/s
n/s
n/s
Treated
(mg/kg)
26,600
22,400
27,700
18,200
32,000
35,000
29,300
31 ,600
34,900
Note: n/s = not sampled.
Table 2-28. Summary Statistics for Hydrofluoric Acid Digestion
Statistic
Untreated Mean
(Standard deviation)
Treated Mean
(Standard deviation)
Mean Difference
(Untreated -Treated)
Significance level
Trailer Park
Data (mg/kg)
1 ,345.7 (987)
666.8(514)
678.9
0.02
Inactive Pottery
Factory Data (mg/kg)
41,500 (17,657)
28,633 (5,625)
12,032
0.0904
Note: Hypothesis associated with significance level is Ho: mean
untreated - mean treated = 0. A paired t-test was conducted on
data from the trailer park, and an unpaired t-test assuming
unequal variances between treated and untreated samples was
conducted on the data from the pottery factory.
Table 2-29 lists the concentrations of SPLP lead in un-
treated and treated soil from the trailer park. The concen-
trations of SPLP lead in untreated soil from the trailer park
all were lowerthan the detection limit of 0.5 mg/L.Ofthe
10 samples of treated soil from the trailer park, 7 contained
concentrations of SPLP lead that were higher than the
detection limit, but none of those concentrations exceeded
the criterion of 5.0 mg/L.The concentrations of SPLP lead
in untreated soil from the trailer park indicate that the con-
taminated soil would not require treatment.
Table 2-30 lists the concentrations of SPLP lead in un-
treated and treated soil from the inactive pottery factory.
The concentrations of SPLP lead in untreated soil from the
inactive pottery factory all were lowerthan the detection
limit of 0.5 mg/L. Of the 9 samples of treated soil from the
inactive pottery factory, 7 contained concentrations of
SPLP lead that were higher than the detection limit, but
none of those concentrations exceeded the criterion of 5.0
mg/L.The concentrations of SPLP lead in untreated soil
from the inactive pottery factory indicate that the contami-
nated soil would not require treatment. A parametric sta-
tistical analysis of the concentrations of SPLP lead in
treated soil cannot be performed because of excessive
number of nondetects. However, the following nonparamet-
ric argument can be made to support a conclusion that the
mean concentration of SPLP lead in treated soil does not
exceed 5.0 mg/L. If the mean was greaterthan or equal to
5.0 mg/L, the probability of observing an individual concen-
tration of SPLP lead higherthan 5.0 mg/L would be at least
0.5. Therefore, the probability of observing 10 independent
samples of treated soil (9 samples at the inactive pottery
factory) at less than 5.0 mg/L could be no more than 0.510
= 0.00098 (0.59 = 0.001953 at the inactive pottery factory)
.Therefore, the hypothesis that the mean concentration of
SPLP lead in treated soil from the trailer park exceeds 5.0
mg/L is rejected at a 0.001 level of significance at the trailer
park and at a 0.01 level of significance at the inactive pot-
tery factory. The statistical analysis of untreated and
treated soil from the trailer park and the inactive pottery
factory did not indicate a statistically significant change in
concentrations of SPLP lead.
Phosphates
Envirobond™ contains phosphoryl esters used to form
metal complexes. Phosphates may be released from the
soil into local streams through stormwater runoff. There-
fore, two analytical procedures were used to evaluate
whether the phosphates in Envirobond™ could be re-
leased into the environment.The methods are comparison
of the total phosphate concentrations in untreated and
treated soils at both sites by SW-846 Method 9056 and
comparison of the concentrations of untreated and treated
soils that leach from untreated and treated soil when the
SPLP test (SW-846 Method 1312) is applied and analysis
of the extract for total phosphates by SW-846 Method
9056.
Table 2-31 lists the total concentrations of phosphate for
soil from the trailer park, and Table 2-32 lists the total con-
centrations of phosphates for soil from the inactive pottery
factory. The data from both sites clearly show significant
increases in the concentrations of phosphates after the
application of Envirobond™.
Table 2-33 lists the concentrations of SPLP phosphates for
untreated and treated soils from the trailer park, and Table
2-34 lists the concentrations of SPLP phosphates for un-
treated and treated soil from the inactive pottery factory.
The data from both sites also clearly show a significant
increase in the concentrations of SPLP phosphates after
the application of Envirobond™.
34
-------
Table 2-29. SPLP Lead Analytical Results for Soil
from the Trailer Park
Experimental
Unit
A
B
D
E
F
H
1
J
P
S
Sampling
Location
Composite
Composite
Composite
Composite
Composite
Composite
Composite
Composite
Composite
Composite
Untreated
(mg/L)
O.50
O.50
<0.50
O.50
O.50
O.50
O.50
<0.50
<0.50
O.50
Treated
(mg/L)
<0.50
<0.50
1.7
3.3
2.3
0.85
0.80
0.52
1.8
<0.50
Table 2-30. SPLP Lead Analytical Results for Soil
from the Inactive Pottery Factory
Experimental
Unit
V
V
V
V
V
V
V
V
V
Sampling
Location
1
2
3
4
5
6
7
8
9
Untreated
(mg/L)
<0.50
<0.50
<0.50
<0.50
<0.50
n/s
n/s
n/s
n/s
Treated
(mg/L)
1.4
1.1
1.4
O.50
0.83
1.6
O.50
1.2
0.65
Note: n/s = not sampled.
Table 2-35 displays the estimated means and 95 percent
confidence intervals for both sets of data on treated soil
from both sites. The estimated mean concentrations of
phosphates were 6,575 mg/kg for the trailer park and
8,085.5 mg/kg for the inactive pottery factory. The esti-
mated mean concentrations of SPLP phosphates were
450.5 mg/L and 322 mg/L forthe the trailer park and inac-
tive pottery factory, respectively. On the basis of the data
obtained by conducting analytical procedures, it appears
that phosphates from the application of Envirobond™
could leach from the soil, a circumstance that could affect
nearby surface water.
Summary
In total, 11 types of analytical procedures were conducted
to predict the long-term stability of the soil treated by
Envirobond™.The results for each procedure for both the
trailer park and the inactive pottery factory were presented
in the preceding subsections and are summarized in the
table titled "Summary of Results for Objective S1".
The results of conducting most of the procedures indicate
that Envirobond™ appears to increase long-term stability.
However, the results of some of the procedures suggest
that Envirobond™ does not increase long-term stability.
Long-term stability of soil was indicated forsoils treated by
Envirobond™ at both test locations, as shown by the ana-
lytical results of the MEP, lead speciation by sequential
extraction, CEC, and SPLP lead test procedures. In addi-
tion, long-term stability of the soil was indicated at one site,
but not at the other, by analytical results of the acid neu-
tralization capacity test.The analytical results ortesting by
the lead speciation by SEM (conducted only on soils from
the trailer park) were mixed in that the silica phosphate
phase (low solubility) was increased and some soluble
species of lead were reduced, while other stable phases
of lead were also reduced. For both locations, long-term
stability of soil was not indicated for soils treated by
Envirobond™ by the results of the pH analyses, Eh analy-
ses, separate analyses fortotal lead by nitric and hydrof-
luoric acids, total phosphates, and SPLP phosphates.
2.4.4 Evaluation of S2
Demonstrate that the application of Envirobond™ does
not increase the public health risk of exposure to lead.
During the demonstration, it was necessary to remove
vegetation with a sod cutter and to prepare the soil forthe
collection of samples before and aftertreatment.The ac-
tivities generated dust that was monitored with real-time
devices. Air sampling devices were used to determine the
total concentrations of lead in the dust. Accomplishment
of S2 was evaluated by collecting air samples through fil-
ters during tilling operations and calculating the exposure
to lead on the basis of total lead content of the air sam-
pling filters and the length of exposure. The concentration
of lead was determined by the nitric acid digestion method
described in Section 2.3.1 .The exposure calculated was
compared with NAAQS for lead, which currently is 1.5/jm/
m3 of air, averaged over a period of three consecutive
months.Table 2-36 lists the exposures calculated forthe
workerduring the demonstration.
The only sample result in the detectable range, 24 g/m3,
occurred on September 25,1998 on the east area sample.
The tilling activity at this plot and the corresponding sam-
pling period were 5 minutes in duration.These values ex-
trapolate to a concentration of 9.3 x 10~4 mg/m3 over a
3-month period, which is lowerthan the NAAQS standard.
Assuming that the concentration was to remain constant
during extended remediation activities; however, the
NAAQS standard would be exceeded after approximately
35
-------
Table 2-31. Total Phosphates Analytical Results for Soil
from the Trailer Park
Experimental
Unit
A
B
D
E
F
H
I
J
P
Sampling
Location
Composite
Composite
Composite
Composite
Composite
Composite
Composite
Composite
Composite
Untreated
(mg/kg)
<12.3
<12.8
<11.5
<12.8
<12.7
<12.0
<12.7
<12.1
<12.3
Treated
(mg/kg)
2350
6050
6250
5950
12000
5550
4380
6480
6510
Table 2-32. Total Phosphates Analytical Results for
Soil from the Inactive Pottery Factory
Experimental
Unit
V
V
V
V
V
V
V
V
V
Sampling
Location
1
2
3
4
5
6
7
8
9
Untreated
(mg/kg)
<13.3
<12.6
<13.6
<13.6
<13.8
n/s
n/s
n/s
n/s
Treated
(mg/kg)
5,680
7,810
3,930
13,000
9,220
5,490
15,000
4,660
7,980
Note: n/s = Not sampled
Table 2-33. SPLP Phosphates Analytical
Results for Soil from the Trailer Park
Experimental
Unit
A
B
D
E
F
H
I
J
P
S
Sampling
Location
Composite
Composite
Composite
Composite
Composite
Composite
Composite
Composite
Composite
Composite
Untreated
(mg/L)
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
<1.0
Treated
(mg/L)
264
409
324
459
723
496
310
352
509
639
Table 2-34. SPLP Phosphates Analytical
Results for Soil from the Inactive Pottery Factory
Experimental
Unit
V
V
V
V
V
V
V
V
V
Sampling
Location
1
2
3
4
5
6
7
8
9
Untreated
(mg/L)
<1.0
<1.0
<1.0
<1.0
<1.0
n/s
n/s
n/s
n/s
Treated
(mg/L)
249
296
171
516
327
213
613
203
310
Note: n/s = not sampled.
135 hours. The application of Envirobond™ does not ap-
pear to create a significant quantity of dust; however, air
monitoring was not conducted during that activity. If it is
determined that it is necessary to remove the soil or use
other techniques that may generate dust, air monitoring
with real-time devices correlated to actual concentrations
of lead in the air (for example, high-volume air samplers)
and, if appropriate, dust suppression measures should be
employed.
2.4.5 Evaluation of Objective S3
Document baseline geophysical and chemical conditions
of the soil before the addition of Envirobond™.
Soil samples collected from the locations at the trailer park
and the inactive pottery factory at which the demonstra-
tion was conducted were analyzed to determine the soil
classification and to determine whether VOCs, SVOCs, or
oil and grease were present in the soils.
One soil sample from each of the demonstration sites was
analyzed by ASTM Method D 2487-93, Standard Classi-
fication of Soils for Engineering Purposes, to determine the
soil classification. The soil type for both sites has been
identified as sandy silt, an organic clay having low plastic
limits and liquid limits of less than 50 percent.
36
-------
Table 2-35. Phosphate Summary Statistics
Location
Trailer Park
Inactive Pottery
Factory
Data
Total
phosphates
(mg/kg)
SPLP
phosphates
(mg/L)
Total
phosphates
(mg/kg)
SPLP
phosphates
(mg/L)
Mean
6,575
450.8
8,085.5
322
95% Confidence
Interval
(5,192—7,958)
(361-541)
(5,610—10,561)
( 225—41 9)
The results of analysis forVOCs did not indicate the pres-
ence of any VOCs in the soils at either site. The analysis
forSVOCs indicated the presence of the following SVOCs
in the soils at the inactive pottery factory:
benzo(a)anthracene (0.82 mg/kg), benzo(b)fluoranthene
(0.91 mg/kg), benzo(k)fluoranthene (0.77 mg/kg),
benzo(a)pyrene (0.69 mg/kg), chrysene (1.0 mg/kg),
fluoranthene (1.9 mg/kg), and pyrene (1.9 mg/kg).Those
SVOCs typically are found in crude oil, fuel oil, or used
motor oil. The soil in that area did show signs of staining
that may have been the result of the disposal of a small
quantity of waste oil. On the basis of the concentrations
detected and the current state regulations governing pe-
troleum releases, it does not appear that the SVOCs
present at the site require remediation. The technology
developer indicated that the SVOC would not interfere with
Envirobond™.The analytical results forthe soil at the in-
active pottery factory indicated that oil and grease were
present at a concentration of 3,680 mg/kg.The analytical
results for the soil at the trailer park did not indicate that
oil and grease were present.
Humicand Fulvic Acids
The soil humus fractions (humic acid and fulvic acid) were
determined from untreated samples collected from both
sites. Humus in soils contributes ligands that can bind with
the lead. These concentrations can be used to evaluate
whetherthe humus is contributing to the concentration of
the lead species bound to organic fractions.That informa-
tion is important when a technology uses humic acids to
bind the lead. However, since Envirobond™ does not use
humic acids to bind the lead, the concentration of humic
acids is provided only as a description of the organic matter
in the soil. The concentration of humic acid in the soil at the
trailer park was 2,400 mg/L, and the concentration of hu-
mic acid in the soil at the inactive pottery factory was 1,400
mg/L. The concentration of fulvic acid in the soil at the
trailer park was 600 mg/L, and the concentration of
fulvic acid at the inactive pottery factory was less than
500 mg/L.
2.4.6 Evaluation of Objective S4
Document the operating and design parameters of
Envirobond™.
On the basis of information obtained through the SITE
evaluation, from RMRS, and from other sources, an eco-
nomic analysis examined 12 cost categories for a scenario
in which Envirobond™ was applied at full scale to treat soil
contaminated with lead at a Superfund site. Forthe cost
estimate, it was assumed that the site was one acre in size
and that the treatment was applied to a depth of 6 inches,
or approximately 807 cubic yards of soil. The estimate
assumed that the soil characteristics and lead concentra-
tions of lead at the site were the same as those encoun-
tered during the CRPAC evaluation. With those
assumptions, the total costs were estimated to be $32,500
per acre or $40.27 per yd3 Costs for application of
Envirobond™ may vary significantly from that estimate,
depending on site-specific factors.
2.5 Quality Control Results
The overall quality assurance (QA) objective forthe SITE
program demonstration, as set forth in the QAPP, was to
produce well-documented data of known quality as mea-
sured by the precision, accuracy, completeness, represen-
tativeness, and comparability of the data, and the
conformance of the data to the project required detection
limits (PRDL) forthe analytical methods. Specific QA ob-
jectives were established as benchmarks by which each
of the criteria was to be evaluated. Section 3.0 of the QAPP
presented the QA objectives forthe critical parameters.
This section discusses the quality control (QC) data with
respect to the QA objective of the project for critical param-
eters. The results, and those for noncritical parameters,
can be found in the unpublished TER for this SITE dem-
onstration (Tetra Tech 2001). The TER is available upon
request from the EPA work assignment manager (see
Section 1.4 for contact information).
QA objectives for laboratory analysis of the critical param-
eter bioavailable lead were evaluated on the basis of ana-
lytical results from matrix spike samples and matrix spike
duplicate samples (MS/MSD), blank spikes, laboratory
control samples (LCS), reagent blanks, bottle blanks, and
calibration criteria. QA objectives for laboratory analysis of
the critical parameter TCLP lead were evaluated on the
basis of MS/MSDs, LCS/LCSD, and method blanks.Table
7-1 of the QAPP summarizes the internal acceptance cri-
teria for laboratory QC samples, as well as corrective ac-
tion procedures forthe demonstration.
2.5.1 Completeness
The QA objective for data completeness specified by the
QAPP is that 100 percent of all planned measurements will
be obtained and will be valid. As discussed in Section 3.1,
SITE Program personnel did not collect an equipment and
field blank during the post-treatment sampling for
bioavailable lead analysis. Analytical results of the pretreat-
ment equipment and field blanks and subsequent long-
term monitoring blanks did not indicate
37
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Summary of Results for Objective S1
Procedure
MEP
Lead speciation by SEM
Lead speciation by sequential
extractions
Eh
PH
CEC1
Acid neutralization capacity1
Total lead by nitric acid
digestion compared with total
lead by hydrofluoric acid
digestion
SPLP lead
Total phosphate
SPLP phosphate
Results
All results met the acceptance
criteria for S1 (see Table 2-4).
Results for 4 of 1 8 phases of
lead met the acceptance criteria
for S1 , and results for one
phase did not meet the criteria.
Results for the other 1 3 phases
did not appear to be affected by
the treatment.
Results for all six phases of
lead at both sites met the
acceptance criteria for S1 .
There was no significant
change in Eh at either site, thus
this criterion for S1 was not met
at either site.
pH was significantly increased
at one site and significantly
decreased at the other site.
Results did not meet the
acceptance criteria for S1 at
either site (see Table 2-4).
All results met the acceptance
criteria for S1 (see Table 2-4).
The criterion for S1 was met for
one site, but was not met for the
other site.
None of the results met the
acceptance criteria for S1 (see
Table 2-4).
The acceptance criterion for S1
was met at both sites.
None of the results met the
acceptance criteria for S1 (see
Table 2-4).
None of the results met the
acceptance criteria for Objective
S1 (See Table 2-4).
Interpretation
Trailer Park
Pottery Factory
Envirobond™ exhibits long-term stability, as indicated by the
results of this procedure.
Mixed: Lead in silica
phosphates appears to
increase, and lead in oxide
phases appear to decrease after
addition of Envirobond™;
however, lead in glass and slag
appears to decrease.
This procedure was not
conducted on soils from this
location.
Envirobond™ exhibits long-term stability, as indicated by the
results of this procedure.
Envirobond™ did not increase long-term stability, as indicated by
the results of this procedure.
Envirobond™ did not increase long-term stability, as indicated by
the results of this procedure.
Envirobond™ did not increase long-term stability, as indicated by
the results of this procedure.
Envirobond™ did not increase
long-term stability, as indicated
by the results of this procedure.
Envirobond™ did not increase
long-term stability, as indicated
by the results of this procedure.
Envirobond™ did not increase long-term stability, as indicated by
the results of this procedure.
Envirobond™ did not increase long-term stability, as indicated by
the results of this procedure. However, SPLP lead concentrations
appeared to be higher in the treated soils.
Envirobond™ did not increase long-term stability, as indicated by
the results of this procedure. However, the increase in
concentrations of phosphate in treated soils is related only
indirectly to long-term stability and therefore is not as meaningful as
the findings for most of the other procedures conducted.
Envirobond™ did not increase long-term stability, as indicated by
the results of this procedure.
1 Only one sample at each site was tested by this procedure.
38
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Table 2-36. Air Monitoring Results
Area
Area Sample
Southwest
Area Sample East
Area Sample
Northeast
Area Sample North
Area Sample
Southwest
Area Sample East
Area Sample
Northeast
Area Sample North
Date
9/22/98
9/22/98
9/22/98
9/22/98
9/25/98
9/25/98
9/25/98
9/25/98
Time Sampled
(minutes)
5
5
5
5
5
5
5
5
Flow Rate
(L/minute)
10
10
10
10
10
10
10
10
Air Volume (L)
50.0
50.0
50.0
50.0
50.0
50.0
50.0
50.0
Lead
Concentration
<4.0 jj g/m3
<4.0fy g/m3
<4.0 jj g/m3
<4.0 p g/m3
<4.0 jj g/m3
24 \i g/m3
<4.0 jj g/m3
<4.0 p g/m3
Notes: jj g/m3 = Micrograms per cubic meter of air
cross-contamination as a result of sample collection or
shipping procedures.Therefore, this deviation should not
impact the overall data quality. All of the soil samples speci-
fied in the QAPP forTCLP lead analysis were collected and
analyzed. All samples were analyzed within the holding
times specified in the QAPP and all of the TCLP lead data
were considered usuable. Therefore, the critical param-
eters of bioavailable and TCLP lead data are considered
to be 100 percent complete.
2.5.2 Comparability and Project-required
Detection Limits
Based on the consistent implementation of a reference
method, pretreatmentand post-treatment data for critical
parameters (bioavailable lead and TCLP lead) are consid-
ered to be comparable. As specified by the QAPP, the
University of Colorado used the SBRC In Vitro Method for
Determination of Lead and Arsenic Bioaccessibility to ana-
lyze soil samples for bioavailable lead and Quanterra used
SW-846 Method 1311 (EPA 1996) to analyze soil samples
forTCLP lead concentrations. The PRDLs specified in
Table 3-1 of the QAPP were achieved for all samples col-
lected during the demonstration.
2.5.3 Accuracy and Precision
Accomplishment of QA objectives for accuracy and pre-
cision were evaluated on the basis of MS/MSD percent
recoveries and relative percent differences (RPD). Percent
recovery and RPD values for LCS/LCSD and blank spike
(BS) samples, also supported QA objectives for accuracy
and precision.
All of the precision and accuracy assessments for the
bioavailable lead data, including the RPD of the duplicates
and the percent recoveries of the MS and BS analyses,
were within the limits specified in the QAPP. Concentration
levels for spiking met the criteria specified in the QAPP for
all analyses. The QC data for the critical and noncritical
parameters are presented in Appendix B.
One TCLP lead MS/MSD sample had a percent recovery
of 124 percent, which is outside the acceptable range of
80 to 120 percent.The batch of samples for which the MS/
MSD analysis was performed were all pretreatment
samples. Therefore, this deviation should not impact the
overall quality of the data forthe demonstration.The data
on untreated soil are not used to determine whether the
technology can meet objective P1, which is to reduce the
TCLP lead concentration to a level lower than the alterna-
tive UTS lead in soil of 7.5 mg/L.The percent recovery of
the LCS/LCSDs were all within the acceptable range of 80
to 120 percent. All of the RPDsforthe MS/MSD and LCS/
LCSD samples were less than 20 percent and were there-
fore acceptable.
2.5.4 Representativeness
The University of Colorado analyzed method blank
samples for bioavailable lead to confirm the representative-
ness of the bioavailable lead data by determining if any
lead was potentially introduced during sample preparation
and analysis. The levels of lead in the method blank
samples did not exceed the criteria in the QAPP for method
blanks, which is 25 /j g/L. Therefore, the method blank
analyses do not indicate that laboratory contamination in-
troduced detectable concentrations of the critical param-
eter bioavailable lead to any of the samples, and the
reported concentrations of the critical parameter
bioavailable lead appear to be representative of actual
concentrations in the soil samples, based on the available
QC data.
39
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Quanterra analyzed method blank samples forTCLP lead
to confirm the representativeness of the TCLP lead data
by determining if any lead was potentially introduced dur-
ing sample preparation and analysis. Quanterra did not
detect any TCLP lead in any of the method blanks above
the PRDL of 0.50 mg/L.Therefore, the method blank analy-
ses do not indicate that laboratory contamination intro-
duced detectable concentrations of the critical parameter
TCLP lead to any of the samples, and the reported con-
centrations of the parameterTCLP lead appearto be rep-
resentative of actual concentrations in the soil samples,
based on the available QC data.
Tetra Tech prepared equipment blank samples and field
blank samples to determine if any lead was potentially in-
troduced by sample collection, handling, and packaging
procedures. The blank sample preparation techniques are
summarized in Section 2.5.1 of the TER.The results of the
equipment and field blank analyses are summarized in
Tables 4-1 and 4-2 of the TER. No lead was detected in any
of these blank samples above the PRDL of 100 /j g/L.
The University of Colorado analyzed the equipment blank
and field blank samples for bioavailable lead to confirm the
representativeness of the bioavailable lead data by deter-
mining if any bioavailable lead was potentially introduced
during sample collection, handling and packaging proce-
dures. The University of Colorado did not detect any
bioavailable lead in any of the equipment and field blanks
above the PRDL of 100 /j g/L. Therefore, the equipment
and field blank analyses do not indicate that sample col-
lection, handling and packaging procedures introduced
detectable concentrations of the critical parameter
bioavailable lead to any of the samples.
Quanterra analyzed the equipment blank and field blank
samples forTCLP lead to confirm the representativeness
of the TCLP lead data by determining if any lead was po-
tentially introduced during sample collection, handling and
packaging procedures. Quanterra did not detect any TCLP
lead in any of the equipment and field blanks above the
PRDL of 0.50 mg/L. Therefore, the equipment and field
blank analyses do not indicate that sample collection, han-
dling and packaging procedures introduced detectable
concentrations of critical parameterTCLP lead to any of
the samples.
40
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3.0 Technology Applications Analysis
This section describes the Envirobond™ technology. It
identifies the waste to which the technology is applicable
and discusses the method of application used during the
demonstration, materials handling requirements, the limi-
tations of the technology, potential regulatory require-
ments, key features, the availability and transportability of
the technology, and acceptance of the technology by state
regulators and communities.
3.1 Description of the Technology
The Envirobond™ process incorporates the application of
a mixture of a proprietary powder and liquid that binds with
metals in contaminated solid media. The Envirobond™
reagents (liquid and powder) consist of a mixture of addi-
tives containing oxygen, sulfur, nitrogen, and phosphorous;
each additive has an affinity for a specific class of metals.
RMRS claims that the Envirobond ™ process converts the
metal contaminant from its leachable form to an insoluble,
stable, nonhazardous organo-metallic complex. The
Envirobond™ reagents are essentially a mixture of ligands
that act as chelating agents. In the chelation reaction, co-
ordinate bonds attach the metal ion to at least two ligand
nonmetal ions to form a heterocyclic ring. RMRS claims
that, by effectively binding the metals, the Envirobond™
process reduces the waste stream's TCLP test results to
less than regulated levels, thereby reducing the risks
posed to human health and the environment (RMRS,
1999). The Envirobond™ process generates no second-
ary wastes and requires minimal handling, transportation,
and disposal costs.
3.2 Applicable Wastes
RMRS claims that the Envirobond™ process can treat
heavy metals in soils, sludges, mine tailings and process
residues, and other solid waste. RMRS states the follow-
ing heavy metals can be stabilized with the Envirobond™
process: arsenic, barium, cadmium, chromium, lead, mer-
cury, nickel, selenium, silver, and zinc (RMRS 1999). Ac-
cording to RMRS, the Envirobond™ process can also
stabilize wastes contaminated with various radionuclides,
including thorium, uranium, radium, and cesium.
3.3 Method of Application
The Envirobond™ process is applied in situ using common
farm and construction equipment at large sites, and with
simple gardening equipment for smaller treatment areas.
For example, the Envirobond™ powder was applied to the
surface of the tilled experimental units at the CRPAC dem-
onstration site with a fertilizer drop spreader. The
Envirobond™ liquid was applied over the powder using a
watering can. The mixture was then tilled into the soil us-
ing a garden tiller. If necessary, flyash can be used to ad-
just the pH of a treatment plot after the application of the
Envirobond™ process. The flyash is spread over the sur-
face of the plot and tilled into the soil.
RMRS determines an appropriate, site-specific concentra-
tion of the Envirobond™ powder and liquid to be applied
by determining the density, volume, weight, and amount of
contamination present in the soil through bench-scale
studies on soil samples. An evaluation of the soil chemis-
try at the site must be performed to determine the contami-
nant concentration throughout the site and the
concentration of other metals that may be present at the
site. Site conditions such as soil type, depth of contamina-
tion, and moisture content must be evaluated to determine
the application procedure and equipment requirements.
The site should be accessible to wheeled or tracked ve-
hicles and have sufficient storage space forthe equipment
required to apply the Envirobond™ process to a specific
site. No utilities are required forthe application of the
Envirobond™ process. Potable water is required for equip-
ment and personnel decontamination.
3.4 Material Handling Requirements
The Envirobond™ powder and liquid are both nonhazard-
ous and require no special handling procedures. To de-
crease the variability of lead in the soil at the CRPAC, the
contaminated soil was tilled to a depth of 6 inches. The soil
must be kept moist to prevent airborne transmission of the
metals in the soil. Once the soil has been tilled, the
Envirobond™ process can be applied. After the applica-
tion of the Envirobond™ mixture, the soil was tilled again
to mix these components into the soil, depending on the
soil conditions. Following the soil treatment, all field equip-
ment and personal protection equipment (PPE) must be
decontaminated. Forthe CRPAC demonstration, this was
accomplished with soap, water, and Alconox™ detergent,
followed by a deionized water rinse. While the
Envirobond™ process is expected to generate little re-
sidual waste, any soil on the equipment, fluids used in the
decontamination process, disposable PPE, and possibly
the sod removed from the treatment plot, should be treated
as a potentially hazardous waste. This waste should be
containerized and characterized forproperdisposal.
3.5 Limitations of the Technology
The presence of metals such as aluminum, magnesium,
calcium, and manganese at concentrations more than 30
41
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percent by weight can reduce the bonding capability of the
Envirobond™ process. RMRS reports that the
Envirobond™ process is not effective in treating soil with
lead concentrations greater than 30 percent by weight.
3.6 Potential Regulatory Requirements
This section discusses environmental regulations that may
pertain to the application of Envirobond™.The applicabil-
ity of regulations to a particular remediation activity de-
pends on the type of remediation site and the type of waste
treated. Remedial managers also must address state and
local regulations, which may be more stringent. ARARs for
applications of Envirobond™, although site-specific, may
include the requirements of following federal regulatory
programs: (1) the Comprehensive Environmental Re-
sponse, Compensation, and Liability Act (CERCLA); (2)
RCRA; (3) OSHA; and (4) the Clean Water Act (CWA).
3.6.1 CERCLA
CERCLA, as amended by the SARA, provides for federal
authority and funding to respond to releases or potential
releases of any hazardous substance into the environ-
ment, as well as to releases of pollutants or contaminants
that may present an imminent or significant danger to pub-
lic health and welfare or to the environment. CERCLA is
pertinent to a consideration of Envirobond™ because it
governs the selection and application of remedial technolo-
gies at Superfund sites.
In general, two types of responses are possible under
CERCLA: removal action and remedial action. Remedial
actions are governed by the SARA amendments to
CERCLA. SARA states a strong regulatory preference for
innovative technologies that provide long-term protection
and directs EPA to:
Use remedial alternatives that permanently and sig-
nificantly 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
Avoid off-site transport and disposal of untreated
hazardous substances or contaminated materials
when practicable treatment technologies exist [Sec-
tion 121 (b)]
SARA requires that on-site remedial actions comply with
federal and more stringent state and local ARARs. ARARs
are determined on a site-by-site basis and may be waived
under any of six conditions: (1) 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 stan-
dard of performance of an ARAR can be met by an equiva-
lent method; (5) a state ARAR has not been applied
consistently elsewhere; or (6) compliance with the ARAR
would not provide a balance between the protection
achieved at a particular site and demands on Superfund
for addressing other sites. The waiver options apply only
to Superfund actions taken on site, and justification forthe
waiver must be demonstrated clearly (EPA 1988).
3.6.2 RCRA
RCRA, as amended by HSWA, regulates management
and disposal of municipal and industrial solid wastes. EPA
and the states implement and enforce RCRA and state
regulations. Some of the RCRA Subtitle C (hazardous
waste) requirements under40 CFR parts 254 and 265 may
apply at CERCLA sites because remedial actions gener-
ally involve treatment, storage, or disposal of hazardous
waste. However, requirements under RCRA may be
waived for CERCLA remediation sites, provided equivalent
or more stringent ARARs are met.
RCRA regulations define hazardous wastes and regulate
theirtransportation, treatment, storage, and disposal.The
regulations are applicable to uses of Envirobond™ only if
hazardous wastes as defined under RCRA are present. If
soils are determined to be hazardous under RCRA (either
because of a characteristic identified in RCRA or listing of
the waste, the remedial manager must address all RCRA
requirements governing the management and disposal of
hazardous waste. Criteria for identifying characteristic
hazardous wastes are set forth in 40 CFR part 261 sub-
part C. Listed wastes from specific and nonspecific indus-
trial sources, off-specification products, cleanups of spills,
and other industrial sources are itemized 40 CFR part 261
subpart D.
Residual wastes generated during the application of
Envirobond™ must be stored and disposed of properly. If
the treated waste is a listed waste, residues of treatment
must be considered listed wastes (unless delisting require-
ments under RCRA are met). If the residues are not listed
wastes, they should be tested to determine whether they
are characteristic hazardous wastes as defined under
RCRA. If the residues are not hazardous and do not con-
tain free liquids, they can be disposed of in a Subtitle D
facility. If the residues are hazardous, the following RCRA
standards apply:
Standards and requirements for generators of haz-
ardous waste, including hazardous treatment resi-
dues, are set forth at 40 CFR part 262. The
requirements include obtaining an EPA identification
number, meeting waste accumulation standards,
labeling wastes, and keeping appropriate records.
Part 262 allows generators to store wastes for as
much as 90 days without a permit. If residues of
treatment are stored on site for 90 days or more,
requirements set forth at 40 CFR part 265 are ap-
plicable.
Any on- or off-site facility designated for permanent
disposal of residues of hazardous treatment must
be in compliance with RCRA. Disposal facilities must
fulfill the permitting, storage, maintenance, and clo-
sure requirements at 40 CFR parts 264 through 270.
42
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In addition, any authorized state RCRA require-
ments must be fulfilled. If treatment residues are
disposed of off site, transportation standards set
forth at 40 CFR part 263 are applicable.
3.6.3 OSHA
OSHA regulations at 29 CFR parts 1900 through 1926 are
designed to protect the health and safety of workers. Cor-
rective actions undertaken under both Superfund and
RCRA must meet OSHA requirements, particularly those
set forth at Section 1910.120, Hazardous Waste Opera-
tions and Emergency Response. Any more stringent state
or local requirements must also be met. In addition, health
and safety plans for site remediation projects should ad-
dress chemicals of concern and include monitoring prac-
tices to ensure that the health and safety of workers are
protected.
PPE must be worn to protect field personnel from known
or suspected physical hazards, as well as air-, soil-, and
water-borne contamination. The levels of PPE to be used
for work tasks must be selected on a site-specific basis.
The level of PPE should be based on known or anticipated
physical hazards and concentrations of contaminants that
may be encountered at a particular site and their chemi-
cal properties, toxicity, exposure routes, and contaminant
matrices. Personnel must wear PPE when site activities
involve known or suspected atmospheric contamination;
when site activities might generate vapors, gases, or par-
ticulates; or when direct contact with substances that af-
fect the skin may occur. Full-face respirators may be
necessary to protect lungs, the gastrointestinal tract, and
eyes against airborne contaminants. Chemical-resistant
clothing may be needed at certain sites to protect the skin
from contact with chemicals that are absorbed through or
destructive to the skin.
The information provided by RMRS and the results of ob-
servations made during the demonstration project indicate
that the contaminants being treated usually are the
determinating factor in the selection of PPE for applications
of Envirobond™. In general, latex or nitrile gloves, Tyvek
coveralls, boot covers, and goggles are recommended for
applying Envirobond™ to contaminated soils.
3.6.4 CWA
The CWA is designed to restore and maintain the chemi-
cal, physical, and biological quality of navigable surface
waters by establishing federal, state, and local discharge
standards. The CWA may affect application of the technol-
ogy because it governs the appropriate manner of man-
aging water used for decontamination activities.
Depending on the concentrations of the contaminants in
the wastewater and any permit requirements, contami-
nated water from the decontamination procedures could
be discharged to a publicly owned treatment works
(POTW). Each POTW has a different limit for lead that is
specified in the POTWs National Pollutant Discharge
Elimination System (NPDES) permit. The POTW will re-
quire disclosure of the contents of the wastewater and will
determine whether contaminants will interfere with the
treatment of the wastewater.
3.7 Availability and Transportability of the
Technology
The Envirobond™ process is available from Rocky Moun-
tain Remediation Services of Golden, Colorado, (see Sec-
tion 1.4 for address and telephone number). The
proprietary powder and liquid are completely nonhazard-
ous and were transported to the CRPAC demonstration
site by a medium-duty truck, which did not require any
special permits or licensing to transport the material. Ac-
cording to RMRS, there are no restrictions on other meth-
ods of transporting the materials. All typical equipment
required for the application of the Envirobond™ process
are generally readily available from local rental companies
and do not need to be obtained from RMRS.
3.8 Community Acceptance by the State
and the Community
State and community acceptance of Envirobond ™ on the
part of state regulatory agencies and affected communi-
ties likely will be site-specific. Because no community out-
reach program has been established for the CRPAC, it is
difficult to predict how communities in the vicinity of the
CRPAC will accept Envirobond ™.
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4.0 Economic Analysis
This economic analysis presents two cost estimates forthe
application of Envirobond™ (not including profit) to com-
mercially remediate soil contaminated with lead.The esti-
mates are based on assumptions and costs provided by
RMRS; data compiled during the SITE demonstration; and
additional information obtained from current construction
cost estimating guidance, as well as experience underthe
SITE Program. Costs forthe technology can vary, depend-
ing on soil conditions, regulatory requirements, and other
site- and waste-specific factors.
Two estimates are presented in this analysis to determine
the costs of applying Envirobond™. The first estimate
(Case 1) is based on costs incurred during the SITE dem-
onstration. The total volume of soil treated at the CRPAC
demonstration site was approximately 5 cubic yards. That
volume was spread over ten 5-foot-by-5-foot-by-0.5 foot
plots and one 6-foot-by-3-foot-by-0.5 foot plot.The second
estimate (Case 2) is fora hypothetical one-acre site at the
CRPAC that would be treated to depth of 0.5-foot. Case 2
represents a typical application of Envirobond™.The cost
estimate for Case 2 is based on extrapolation of data from
the costs of the SITE demonstration. For Case 2, the total
volume of soil to be treated is 807 cubic yards. Two sce-
narios are presented because of certain "fixed" costs re-
lated to the use of the technology, the unit cost per volume
drops significantly when it is applied to larger volumes of
material.
This section summarizes factors that influence costs, pre-
sents assumptions used in the analysis, discusses esti-
mated costs, and presents the conclusions of the
economic analysis. Table 4-1 presents the estimated costs
generated by the analysis. Costs have been distributed
among 12 categories that are applicable to typical cleanup
activities at Superfund and RCRA sites (Evans 1990).
Costs are presented in 1998 dollars, are rounded to the
nearest 100 dollars, and are considered to be minus 30
percent to plus 50 percent order-of-magnitude estimates.
4.1 Factors that Affect Costs
Costs for implementing Envirobond™ can be affected by
site-specific factors, including the regulatory status of the
site, waste-related factors, total volume of soil to be
treated, site features, and soil conditions. The regulatory
status of the site typically depends on the type of waste
management activities that occurred at the site, the rela-
tive risk to nearby populations and ecological receptors,
the state in which the site is located, and other factors.The
site's regulatory status affects costs because it makes the
site subject to mandates related to ARARs and
remediation goals that may affect the system design pa-
rameters and the duration of the remediation project. Cer-
tain types of sites may be subject to more stringent
monitoring requirements than others, depending on the
regulatory status of the individual site. Soil conditions at the
site determine the possible treatment depth, which can
affect costs.
Factors related to the waste that affect costs include the
volume, distribution, and type of contamination at the site,
which have a direct effect on site preparation costs; the
amount of Envirobond™ needed; and the amount of time
necessary to treat the soil.The type and concentration of
the contaminant also will affect disposal costs for wastes
generated by the remediation effort.
The location and physical features of the site will affect the
cost of mobilization, demobilization, and site preparation.
Mobilization and demobilization costs are affected by the
distances that system materials must be transported to the
site. For high-visibility sites in densely populated areas,
stringent security measures and minimization of obtrusive
construction activities, noise, dust, and air emissions may
be necessary. Sites requiring extensive surficial prepara-
tion (such as constructing access roads, clearing large
trees, orworking around ordemolishing structures) orres-
toration activities also will incur higher costs than sites that
do not require such preparation. The availability of exist-
ing electrical power and water supplies may facilitate con-
struction activities and lower costs. In the United States
significant regional variations may occur in the costs of
materials, equipment, and utilities.
4.2 Assumptions of the Economic Analysis
For Case 1, existing technology and site-specific data from
the demonstration were used to present the costs of ap-
plying Envirobond™ at the CRPAC demonstration site.
Certain assumptions were made to account for variable
site and waste parameters for Case 2. In general, most
system operating issues and assumptions are based on
information provided by RMRS and observations made
during the SITE demonstration. For both cases, costs were
based on information provided by RMRS, observations
made and data collected during the SITE demonstration,
current environmental restoration cost guidance (R.S.
Means [Means] 1998), and experience underthe SITE
program.
44
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Table 4-1. Cost Distribution for Envirobond™
Cost Categories
Case 1 (5 yd3)
Costs
Cost/yd3
% Costs
(1) Site Preparation
Rental Equipment
Labor and Per Diem
Total Site Preparation Costs
(2) Permitting and Regulatory
$30
$1,350
$1 ,400
—
$280
—
$5.41
—
(3) Mobilization
Mileage
$400
Labor and Per Diem $3,1 00
Total Mobilization Costs
$3,500
$700
$13.52
(4) Equipment
Rental Equipment
Purchased Equipment
Total Equipment Costs
$50
$250
$300
$60
$1.16
(5) Labor
Labor
Per Diem
Total Labor Costs
$12,100
$2,480
$14,580
$2,916
$56.34
(6) Supplies and Materials
Envirobond™
Sampling Supplies
$100
$200
Case 2 (807 yd3)
Costs
Cost/yd3
% Costs
$115
$1 ,350
$1 ,500
—
$1.86
—
$4.52
—
$400
$3,100
$3,500
$4.34
$10.54
$700
—
$700
$0.87
$2.11
$7,320
$800
$8,120
$10.06
$24.44
$8,900
$400
Note: 1998 dollars.
(continued)
45
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Table 4-1. Cost Distribution for Envirobond™ (continued)
Cost Categories
PPE and Decontamination Supplies
Misc. Field Supplies
Total Supplies and Materials Costs
(7) Utilities
(8) Effluent Treatment & Disposal
(9) Residual Waste Shipping
(10) Analytical Services
(1 1 ) Equipment Maintenance
Case 1 (5 yd3)
Costs
$500
$200
$1 ,000
—
—
—
$1 ,600
—
Cost/yd3
$200
—
—
—
$320
—
% Costs
$3.86
—
—
—
$6.18
—
(12) Site Demobilization
Mileage
Labor and Per Diem
Total Site Demobilization Costs
Total Costs
$400
$3,100
$3,500
$25,880
$700
$5,176
$13.52
$100.00
Case 2 (807 yd3)
Costs
$800
$900
$11,000
—
—
$700
$4,200
—
Cost/yd3
$13.63
—
—
$0.87
$5.20
—
% Costs
$33.11
—
—
$2.11
$12.64
—
$400
$3,100
$1 ,500
$33,220
$4.34
$41.16
$10.54
$100.00
Note: 1998 dollars.
For both cases, assumptions made about site- and waste-
related factors for both cases include:
The two sites are located in the CRPAC, where dis-
posal of broken and "off-spec" pottery having lead-
based glazes has contaminated the soil with lead.
The total volume of material treated for Case 1 is
approximately 5 cubic yards. The total volume of soil
to be treated for Case 2 is 807 cubic yards.
There is an existing access road, and there are no
accessibility problems associated with the two sites.
There are no structures on either site that require
demolition. No utilities are present that require relo-
cation orthat restrict operation of heavy equipment.
For Case 1, it is assumed that the sod covering the
site can be removed with sod cutters and can be
replaced after the soil has been treated. For Case
2, it is assumed that some clearing and grubbing will
be necessary to prepare the site forthe application
of Envirobond™.
Electricity for both sites can be provided by a por-
table generator.
For both cases, the highest levels of contaminated
soil extend from the ground surface to a depth of
approximately 6 inches below ground surface.
This estimate assumes that the wastes generated
during the application of Envirobond™ are limited to
those produced during decontamination of equip-
ment used during the application. For Case 1, re-
sidual waste will be disposed of on site. For Case 2,
waste generated during the decontamination activi-
ties can be treated and disposed of at easily acces-
sible facilities. Wastewater can be discharged to a
POTWfor$1 pergallon.Nonhazardous solid waste
can be transported and disposed of for $60 perton.
For both cases, the assumptions about system design and
operating parameters for both cases include:
RMRS provides on-site personnel during all phases
of the treatment.
46
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An hourly labor rate of $47.40 is used for site prepa-
ration and sampling activities. The rate represents
the average labor rate, based on the demonstration.
A labor rate of $54 per hour is used for all other ac-
tivities. That is the rate used by RMRS for a field
chemist.
A per diem of $80 per worker per day is assumed.
Routine labor requirements consist of soil prepara-
tion, sampling of untreated and treated soil, and
application of Envirobond™.
Maintenance costs are included in the equipment
rental cost.
Envirobond™ liquid and powder are transported
from the office of RMRS in Golden, Colorado, to the
CRPAC.
It is assumed that 22 samples are collected for Case
1, and 58 samples are needed for Case 2.
Costs are presented as 1998 dollars.
There are no utility costs for either case.
4.3 Cost Categories
Table 4-1 presents cost breakdowns for each of the 12 cost
categories for Envirobond™: (1) site preparation, (2) per-
mitting and regulatory, (3) mobilization, (4) capital equip-
ment, (5) labor, (6) supplies and materials, (7) utilities, (8)
effluent treatment and disposal, (9) residual waste shipping
and handling, (10) analytical services, (11) equipment
maintenance, and (12) site demobilization. Each ofthe 12
cost categories is discussed below. The costs for each
category have been rounded up to the nearest $50 or
$100.
4.3.1 Site Preparation Costs
Forthe purposes of this economic analysis, it is assumed
that preliminary site preparation will be performed by the
responsible party (or site owner). The amount of prelimi-
nary site preparation required will depend on the site. Site
preparation responsibilities include site design and layout,
surveys and site logistics, legal searches, access rights
and roads, preparation for support and decontamination
facilities, utility connections (if needed), and potentially,
fixed auxiliary buildings. Since these costs are site-specific,
they are not included as part ofthe site preparation costs
in the estimates.
For this cost analysis, only technology-specific site prepa-
ration costs are included.These costs are limited to pre-
paring the site for the application ofthe Envirobond™
process by tilling the soil to the appropriate treatment
depth, and removing the grass covering the site with a sod
cutter or by tilling it into the soil. The treatment depth for
both cases is 6 inches. Site preparation costs for both
cases are presented in Table 4-2.
For Case 1, sod covering the site is assumed to be re-
moved with sod cutters and stored until it can be replaced
after the treatment. Site preparation costs for Case 1 in-
clude rental costs for sod removal and tilling equipment,
labor, and per diem. Assuming three workers, earning an
estimated labor rate of $47.40 per hour, can prepare the
site in 8 hours (one business day), the total labor cost as-
sociated with site preparation activities for Case 1 is ap-
proximately $1,100. A per diem of $80 per worker per day
is assumed, adding an additional $240 to the total site
preparation cost. Weekly rental costs for the tiller and sod
cutters, determined from actual demonstration costs, are
approximately $200, bringing the daily rental cost to ap-
proximately $30. Therefore, the total cost for site prepara-
tion for Case 1 is estimated to be approximately $1,400.
For Case 2, site preparation costs include costs associated
with tilling equipment, labor, and per diem. Since the site
will have to be tilled with larger, production-sized equip-
ment, it is assumed that the 1-acre site can be prepared
in 8 hours and that all grass covering the site will be tilled
into the soil.Tilling equipment forthe 1-acre site would in-
clude a medium-duty tractor with a plow. Based on several
vendorquotes, the weekly rental rate forthis equipment is
estimated to be $800, bringing the daily cost forthis equip-
ment to approximately $115. Assuming three workers,
earning an estimated labor rate of $47.40 per hour, labor
costs associated with Case 2 will be $1,100.The total per
diem for the 3 workers is $240. This brings the total site
preparation costs for Case 2 to an estimated $1,500.
4.3.2 Permitting and Regulatory Costs
Permitting and regulatory costs are generally the obliga-
tion ofthe responsible party (or site owner), and not that
ofthe vendor.These costs may include actual permit costs,
system monitoring requirements, the development of
monitoring and analytical procedures, and health and
safety monitoring. Permitting and regulatory costs can vary
greatly because they are site-and waste-specific. In appli-
cations ofthe Envirobond™ process as part of a soil
remediation program, permitting and regulatory costs will
vary depending on whether remediation is performed at a
Superfund or RCRA corrective action site. Superfund site
remedial actions must be consistent with ARARs of envi-
ronmental laws, ordinances, regulations, and statutes, in-
cluding federal, state, and local standards and criteria.
Table 4-2. Site Preparation Costs
Cost Category
Rental equipment
Labor (24 hours total)
($47.40/hour x 8 hrs x 3 workers)
Per diem ($80/worker/day x 1
day x 3 workers)
Total Site Preparation Costs
Case 1
$30
$1,100
$240
$ 1 ,400
Case 2
$ 115
$1,100
$240
$ 1 ,500
Note: 1998 dollars.
47
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Remediation at RCRA corrective action sites requires
additional monitoring and recordkeeping, which can in-
crease the base regulatory costs.
No permitting costs are included in this analysis; however,
depending on the treatment site, they may be a significant
factorsince permitting can be expensive and time consum-
ing.These costs are not included in this analysis because
no regulatory permits were required for Case 1 .This was
due to the fact that the demonstration sites were neither
Superfund nor RCRA sites. Permits may be needed for air
emissions if the site preparation activities produce signifi-
cant quantities of dust. However, air emissions can be
controlled by wetting the soil to be treated during the till-
ing activities.These costs are expected to be negligible and
are not included in this estimate. For Case 2, it is assumed
that no permitting and regulatory costs will be incurred for
air emissions or for the transportation and disposal of re-
sidual wastes generated during the treatment activities.
This is based on the assumption that wastes generated for
Case 2 will be nonhazardous and can be transported and
disposed of at a Subtitle D landfill for $60 perton. Residual
wastes generated at other sites may be classified as haz-
ardous waste, and would require the transport and dis-
posal facility to have appropriate RCRA permits.
4.3.3 Mobilization Costs
Table 4-3 presents the mobilization costs for both cases.
Mobilization costs consist of mobilizing personnel and
transporting materials to the site. For both cases, it is as-
sumed that some equipment and materials are transported
by a medium-duty truck from the office of RMRS in Golden,
Colorado, to the CRPAC. The distance between Golden,
Colorado, and the CRPAC site in Crooksville/Roseville,
Ohio, is approximately 1,350 miles. RMRS mobilized two
field personnel and one truck forthe SITE demonstration.
It is assumed that for Case 2, two personnel and one truck
will also be mobilized. Assuming the standard government
mileage reimbursement rate of 31 cents per mile, mileage
costs from Golden, Colorado, to the CRPAC were approxi-
mately $400. The drive from Golden, Colorado, to the
CRPAC site requires approximately 24 hours of driving
time. Labor costs for mobilizing two personnel (for a total
of 48 hours of labor) earning an estimated laborrate of $54
per hour are approximately $2,600. Assuming the trip is
completed in 3 days, and a per diem of $80 perworkerper
day, the total per diem charges for two people is $480. The
total mobilization cost for both cases is approximately
$3,500. Mobilization of personnel and materials to other
sites could be accomplished in a number of ways. For ex-
ample, materials could be shipped by a carrier service and
personnel flown to the site. These options should be ex-
plored to minimize the cost of mobilization.
4.3.4 Equipment Costs
Equipment costs for both cases are presented in Table 4-
4. Rental equipment used for Case 1 consisted of a tiller
to loosen and mix the soil at the site. This equipment was
used over a 2-day period.The daily rental cost forthe tiller
is approximately $23 (when rented for 1 week).Therefore,
the total cost of rental equipment for Case 1 was approxi-
mately $46. Purchased equipment used for Case 1 con-
sisted of a watering can, fertilizer spreader, a graduated
cylinder for mixing the Envirobond™ process, and a pres-
sure sprayer for decontamination. The total cost for pur-
chased equipment for Case 1 was approximately $250.
Therefore, the total cost of equipment for Case 1 is approxi-
mately $300.
It is assumed that for Case 2 the application of the
Envirobond™ process will require larger, production-sized
equipment. The equipment necessary for Case 2 should
be rented in orderto minimize costs. Equipment for Case
2 is assumed to be a tractor with both a plow and a fertil-
izer spreader, and a 2500-pounds per square inch (psi)
pressure washer for decontamination. For Case 2, it is
assumed that the treatment will require 3 days. The daily
rental cost forthe tractor and plow is approximately $115,
bringing the cost for this equipment to $345 for the 3-day
period.The combined 1-week rental rates forthe pressure
washer and the fertilizer sprayer are estimated to be $800,
bringing the daily rental cost forthis equipment to $115. For
the 3-day time period assumed for Case 2, the cost forthe
pressure sprayer and the fertilizer sprayer is $345. There-
fore, the total equipment cost for Case 2 is estimated at
approximately $700.
4.3.5 Labor Costs
Once the site has been prepared and the technology has
been mobilized, labor requirements for applying the
Envirobond ™ process are minimal. Labor costs are sum-
marized in Table 4-5. Sampling labor costs for Case 1 con-
Table 4-3. Mobilization Costs
Cost Category
Mileage
Labor (40 hours total) ($54/hr x 20
hrs x 2 workers)
Per diem ($80/worker/day x 3 days
x 2 workers)
Total Mobilization Costs
Case 1
$400
$ 2,600
$480
$ 3,500
Case 2
$400
$ 2,600
$480
$ 3,500
Note: 1998 dollars.
Table 4-4. Equipment Costs
Cost Category
Rental equipment
Purchased equipment
Total Capital Equipment Cost
Case 1
$50
$250
$300
Case 2
$700
—
$700
Note: 1998 dollars.
48
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sisted of five field personnel for 5 days, at an estimated
labor rate of $47.40 per hour. During the demonstration
project, sample collection efforts included collecting sig-
nificantly more samples than would be expected for Case
2. Therefore, it is assumed that two field personnel will be
required for Case 2 sampling activities, at an estimated
labor rate of $47.40 per hour. It is also assumed that two
workers will be required for the treatment activities, at a
rate of $54 per hour. All workers are assumed to receive
a per diem of $80 per day to cover lodging, food, and ex-
penses. For Case 1, it is assumed that the amount of time
required to sample and treat the site will be the same as
that required forthe SITE demonstration. Pretreatment and
post-treatment sampling activities lasted 5 days, and re-
quired a total of 200 hours of labor. Labor costs associated
with the sampling activities for Case 1 were approximately
$9,500. The treatment performed by RMRS required 24
hours and lasted 3 days, fora total of 48 hours of labor. The
total labor cost forthe treatment activities associated with
Case 1 was approximately $2,600. The total per diem for
two workers over the 5-day period was $800. Therefore,
the total labor costs associated with Case 1, including per
diem, was $5,500.
For Case 2, sampling activities will require a total of 64
hours of labor, bringing the total labor costs for the sam-
pling activities for Case 2 to $3,000. It is assumed that
treatment activities for Case 2 will require approximately
80 hours of labor over a 5-day period, bringing labor costs
associated with treatment activities for Case 2 to an esti-
mated $4,320. The total labor cost for Case 2 is estimated
to be approximately $7,320. The total per diem for two
workers over the 5-day period is $800. Therefore, the to-
tal labor costs associated with Case 2, including per diem,
is estimated to be $8,120. Labor costs associated with
laboratory analytical costs are included in Section 4.3.10,
Analytical Services.
4.3.6 Supplies and Materials Costs
The necessary supplies forthe soil sampling activities and
the application of the Envirobond™ process include the
Envirobond™ mixture, sampling supplies, Level D dispos-
able PPE (latex rubbergloves), decontamination supplies,
and miscellaneous field supplies. The costs for supplies
and materials are presented in Table 4-6.The total cost of
the Envirobond™ mixture reported by RMRS for Case 1
was $55 (RMRS 1999). Disposable PPE typically consists
of latex inner gloves and nitrile outer gloves. Decontami-
nation supplies consist of soap, deionized water, and
Alconox. PPE and decontamination supplies cost approxi-
mately $500 for Case 1. Sampling supplies include sample
bottles, labels, a 5-gallon bucket with lid, sieves, and ship-
ping containers. Sampling supplies cost approximately
$200 for Case 1. Field supplies include water for person-
nel, coolers, field notebooks, an outdoor canopy, and other
miscellaneous supplies. Field supplies cost an estimated
$200. Total supply and materials costs for Case 1 were
approximately $1,000.
For Case 2, it is assumed that approximately 161 times as
much soil (by volume) will be treated with the Envirobond™
mixture. Assuming a linear cost to volume ratio, the total
cost of the Envirobond™ mixture for Case 2 is estimated
to be approximately $8,900. Because Case 2 represents
a larger application of the technology, expenses for PPE,
decontamination supplies, sampling supplies, and field
supplies are expected to be higherthan the costs associ-
ated with Case 1. PPE and decontamination supplies are
estimated to cost approximately $800 for Case 2. Sampling
supplies are expected to cost approximately $400 for Case
2. The cost of field supplies for Case 2 is estimated to be
$900. This brings the total supply cost for Case 2 to ap-
proximately $11,000.
4.3.7 Utilities Costs
Electricity is not required forthe application of the
Envirobond™ process. For this reason, no electrical util-
ity connection costs are associated with either case. Wa-
ter is required to mix the Envirobond™ solution on site, for
personnel, equipment decontamination, and possibly
ground wetting to control dust. Water costs are insignificant
and are therefore not included in the estimate.
4.3.8 Effluent Treatment and Disposal Costs
No effluent is produced during the application of
Envirobond™.
4.3.9 Residual Waste Shipping and Handling
Costs
One of the key features of the Envirobond™ process is that
it does not produce significant amounts of residual waste.
Residual wastewater is generated during decontamination
Table 4-5. Labor Costs
Cost Category
Sampling Labor ($47.40/hr x
hours)
Treatment Labor ($54/hrx
hours)
Per Diem ($80/worker/day x
5 days x 2 workers)
Total Labor Costs
Case 1
9,500 (200
hours total)
2,600 (48
hours total)
2,480
1 4,580
Case 2
3,000 (64
hours total)
4,320 (80
hours total)
800
8,120
Note: 1998 dollars.
Table 4-6. Supplies and Materials Costs
Cost Category
Envirobond™ Mixture
Sampling Supplies
PPE + Decontamination Supplies
Miscellaneous Field Supplies
Total Supplies and Materials Costs
Case 1
$100
$200
$500
$200
$1,000
Case 2
$8,900
$400
$800
$300
$11,000
Note: 1998 dollars.
49
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of equipment and personnel. For Case 1, the amount of
residual wastewater was negligible. OEPA determined the
residual wastewater would not further impact the soil or
groundwater on the site, and allowed the disposal of the
wastewater on site by pouring the wastewater onto the soil
in the demonstration area.Therefore, no costs fordisposal
of wastewater are included in the analysis for Case 1. It is
assumed that the only solid wastes generated from the
application of the Envirobond™ process are used dispos-
able PPE and soil derived during the decontamination of
field equipment. For Case 1, the amount of residual solid
waste was negligible. The small amount of residual waste
produced during the demonstration was classified as non-
hazardous. The waste was disposed as solid waste. The
owner of the property provided a dumpsterforthe disposal
of the waste. Therefore, no costs for residual waste dis-
posal are included in this estimate for Case 1.
For Case 2, it is assumed that one 55-gallon drum of re-
sidual wastewater will be generated during the decontami-
nation activities. For this cost estimate, it is assumed that
the disposal cost is $500 per 55-gallon drum. It is also
assumed that one 55-gallon drum of nonhazardous solid
waste will be generated.The disposal cost for non-hazard-
ous solid waste is estimated at $200 per 55-gallon drum.
Therefore, the total estimated cost for residual waste dis-
posal for Case 2 is $700. If the residual solid waste was
hazardous, disposal costs would likely be more expensive.
4.3.10 Analytical Services Costs
Analytical services include costs for laboratory analyses,
data reduction, and QA/QC. Sampling frequencies and
number of samples are highly site-specific. Therefore, the
costs reflected in this analysis may not be applicable to
other sites. A total of 292 samples were collected at the
CRPAC demonstration site, which included 145 samples
collected during the pretreatment stage and 147 samples
collected during the post-treatment stage of the demon-
stration.The large number of samples were taken to make
certain that the stringent demonstration objectives could
be thoroughly evaluated.
For Case 1, which represents a demonstration-sized or
pilot-scale application of the technology, fewer samples will
be needed. It is assumed that one composite sample will
be taken from each of the 11 plots during the pretreatment
and post-treatment sampling events, for a total of 22
samples for Case 1. It is also assumed that for both cases
the TCLP will be the only parameter analyzed, since this
will determine whether the treatment has reduced metal
concentrations to below the regulated levels.The average
unit cost per sample for the TCLP analyses performed for
the SITE demonstration was $73.This figure includes ana-
lytical services costs for standard QA/QC samples. Since
the site characteristics for both cases are assumed to be
identical to the CRPAC demonstration site, it is assumed
that the average cost per sample will remain the same. For
Case 1, the total analytical costs for the TCLP analysis of
22 samples is approximately $1,600.
For Case 2, it is estimated that 58 composite samples must
be taken to obtain a statistically valid population. In order
to estimate the number of samples, treated TCLP data
from the SITE demonstration was used and assumed to
be representative of the variance (0.35 [mg/L]2) of treated
lead concentrations at the Case 2 site. It was assumed that
this data set could be adequately described by a normal
distribution. A hypothesis test was set up to compare the
treated concentration to 7.5 mg/L (10 times the UTS, and
the regulatory action level), with the null hypothesis stat-
ing that the average treated concentration is greater than
7.5 mg/L.
Sample size calculations are based on using the one
sample t-test statistic. Equation 4-1 was used to determine
the appropriate number of samples.
(4-1)
where
Var(A) = Variance of the treated data from the
SITE demonstration
5 = Minimum detectable difference from 10
times the UTS
Za = Value from standard normal such that a
is the area under the curve to the right
of this value
Z p = Value from standard normal such that (3
is the area under the curve to the left of
this value
The variables a and (3 are probabilities associated with
Type I and Type II errors, respectively. For this analysis, an
a level of 0.1 was defined as acceptable to meet the goals
of the study. A (3 level of 0.1 was used with a minimum
detectable difference (8), of 0.2 mg/L. Values for Za and
Z^were obtained from a table of standard normal val-
ues.
In order to obtain the desired confidence levels (90 per-
cent) and minimum detection level (0.2 mg/L), at least 58
composite samples must be analyzed at the site. There-
fore, the 58 samples to be analyzed by the TCLP bring the
total analytical costs for Case 2 to an estimated $4,200.
4.3.11 Equipment Maintenance Costs
All equipment used in the application of the Envirobond™
process can be rented.This option, coupled with the fact
that the Envirobond™ process can be applied in a short
period of time, eliminates the need foron-site equipment
maintenance. For these reasons, no maintenance costs
are included in this analysis. Equipment maintenance
costs, for projects other than the two cases considered in
this analysis, may need to be considered depending on the
volume of soil to be treated, soil conditions, and the length
of time required to treat the contaminated soil.
4.3.12 Site Demobilization Costs
Site demobilization costs consist of demobilizing person-
nel and transporting materials from the site. For both
50
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cases, it is assumed that some equipment and materials
are transported by a medium-duty truck from the demon-
stration site to the office of RMRS in Golden, Colorado.The
distance between the CRPAC site in Roseville, Ohio, to
Golden, Colorado, is approximately 1,350 miles. RMRS
demobilized two field personnel and one truck. It is as-
sumed that for Case 2, two personnel and one truck will
also be demobilized. Assuming the standard government
mileage reimbursement rate of 31 cents per mile, mileage
costs from the demonstration site to Golden, Colorado,
were approximately $400. The drive from the demonstra-
tion site to Golden, Colorado, requires approximately 24
hours of driving time. Labor costs for demobilizing two
personnel (for a total of 48 hours of labor) earning an es-
timated labor rate of $54 per hour are approximately
$2,600. Assuming the trip is completed in three days, and
a per diem of $80 per worker per day, the total per diem
charges for two personnel is $480. The total site demobi-
lization cost for both cases is approximately $3,500. De-
mobilization of personnel and materials to othersites could
be accomplished in a number of ways. For example, ma-
terials could be shipped via a carrier service and person-
nel flown from the site. These options should be explored
to minimize the cost of demobilization.Table 4-7 presents
a summary of site demobilization costs for Case 1 and
Case 2.
4.4 Summary of the Economic Analysis
Two cost estimates are presented for applying the
Envirobond™ process to remediate lead-contaminated
soil in the CRPAC. Both cases are based directly on costs
from the demonstration. The first case (Case 1) involves
a cost estimate fora demonstration-scale application, and
the second case (Case 2) involves a larger 1-acre site
having conditions identical to those encountered at the
Case 1 site. Table 4-1 shows the estimated costs and the
percent distributions associated with the 12 cost catego-
ries presented in this analysis for both cases.
For Case 1, important cost categories included site prepa-
ration (5.41 percent), mobilization (13.52 percent), labor
(56.34 percent), supplies and materials (3.86 percent),
analytical services (6.18 percent) and site demobilization
(13.52 percent). No costs were incurred in the other cost
categories (permitting and regulatory, utilities, effluent
treatment and disposal, residual waste shipping and han-
dling, and equipment maintenance) for Case 1. For Case
2, important cost categories included mobilization (10.54
percent), labor (24.44 percent), supplies and materials
(33.11 percent), analytical services (12.64 percent), and
site demobilization (10.54 percent). The costs for site
preparation (4.52 percent), equipment (2.11 percent), and
residual waste shipping and handling (2.11 percent), were
also significant for Case 2. No costs were incurred in the
other cost categories (permitting regulatory, utilities,
and equipment maintenance) for Case 2.
Table 4-7. Site Demobilization Costs
Cost Category
Mileage
Labor (40 hours total)
($54/hr x 20 hrs x 2 workers)
Per diem
($80/worker/day x 3 days x 2 workers)
Total Demobilization Costs
Case 1
$400
$2,600
$480
$3,500
Case 2
$400
$2,600
$480
$3,500
Note: 1998 dollars.
51
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5.0 Technology Status
RMRS has completed several bench-scale studies and The Envirobond™ process is currently being used to sta-
pilot-scale tests on soil and debris contaminated with bilize waste and debris contaminated with radionuclides at
heavy metals and radionuclides. Appendix B provides several full-scale sites. The SITE demonstration in
details on some of the projects where the Envirobond™ Roseville, Ohio, was the second pilot-scale demonstration
process has been tested or applied on a full-scale basis, that RMRS has completed (Tetra Tech 1999d).
52
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References
Canadian Society of Soil Science. 1993. "Soil Sampling
and Methods of Analysis." Chapters 19 and 38. Lewis Pub-
lishers. 1993.
Evans, G. 1990."Estimating InnovativeTreatmentTechnol-
ogy Costs for the SITE Prog ram." Journal of Air and Waste
Management Association. Volume 40, Number 7. July.
Environment Canada Method Number 7.
Interstate Technology and Regulatory Cooperation (ITRC)
Work Group. 1997. "Emerging Technologies for the
Remediation of Metals in Soils: /ns/fuStabilization/lnplace
Inactivation." December.
R.S. Means, Company, Inc. 1998. Environmental Restora-
tion Assemblies Cost Book. R.S. Means Company, Inc.,
Kingston, Massachusetts.
Northern Kentucky University (NKU). 1999. Letter Regard-
ing Technical Review of Soil Amendment Technologies,
Cation Exchange Capacity Assessment. From Lee Otte,
Senior Consultant. To David Gilligan, Project Manger, Tetra
Tech EM Inc. (Tetra Tech) October 7.
Ohio Environmental Protection Agency. 1998. "Interim
Report and Proposal for Additional Work, Crooksville/
Roseville Pottery Area of Concern Geographic Initiative."
March. Prepared for Environmental Protection Agency.
Rocky Mountain Remediation Services, L.L.C. (RMRS)
1999. Facsimile Regarding Costs Associated with the
Envirobond™ Process. From Mike Harper, RMRS, to
David Remley, Tetra Tech. July.
Solubility/Bioavailability Research Consortium (SBRC).
1998. "Simplified In Vitro Method for Determination of Lead
and Arsenic Bioaccessibility" Unpublished.
Tessier, A. 1979. "Sequential Extraction Procedure forthe
Speciation of Particulate Trace Metals." Analytical Chem-
istry. Volume 51, Number 7. Pages 844-850.
Tetra Tech EM Inc. (Tetra Tech) 1998. "Evaluation of Soil
Amendment Technologies at the Crooksville/Roseville
Pottery Area of Concern: SITE Program Final Quality As-
surance Project Plan." Prepared for EPA under Contract
No. 68-35-0037. November.
Tetra Tech 1999a. "Technology Capsule for Rocky Moun-
tain Remediation Services Envirobond™ Process." July.
Tetra Tech 1999b. Rocky Mountain Remediation Services,
L.L.C. "Evaluation of Soil Amendment Technologies at the
Crooksville/Roseville Pottery Area of Concern: SITE Pro-
gram Demonstration Technology Evaluation Report." Pre-
pared for EPA under Contract No. 68-35-0037. December.
Tetra Tech 1999c. "Evaluation Bulletin for Rocky Mountain
Remediation Services Envirobond™ Process." June.
Tetra Tech 1999d. Telephone communication between
Chris Preston, Tetra Tech, and Rich Jensen, RMRS. Au-
gust 6.
U.S. Environmental Protection Agency (EPA). 2000. EPA
Region 9 Preliminary Remediation Goals (PRG 2000)
November http://www.epa.gov/region09/waste/sfund/prg/
index.htm
EPA. 1988. Protocol for a Chemical Treatment Demonstra-
tion Plan. Hazardous Waste Engineering Research Labo-
ratory. Cincinnati, Ohio. April.
EPA. 1996. Test Methods for Evaluating Solid Waste, Vol-
umes IA-IC: Laboratory Manual, Physical/Chemical Meth-
ods; and Volume II: Field Manual, Physical/Chemical
Methods, SW846, Third Edition, Update III, Office of Solid
Waste and Emergency Response, Washington D.C. De-
cember.
EPA. 1983. Methods for Chemical Analysis of Water and
Wastes EPA -600/4-79-020, Environmental Monitoring
and Support Laboratory, Cincinnati, Ohio, and subsequent
EPA-600/4 technical additions.
53
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Appendix A Vendor Claims
(Note: All information in this appendix was provided by the
vendor, Rocky Mountain Remediation Services (RMRS).
Inclusion of any information is at the discretion of RMRS,
and does not necessarily constitute U.S. Environmental
Protection Agency concurrence or endorsement.)
A1. Introduction
In the past five years, Rocky Mountain Remediation Ser-
vices, L.L.C. (RMRS) has developed and field deployed an
innovative, easy to use process for immobilizing heavy
metals in soils and soil-like waste. This process uses a
non-hazardous chemical binder called Envirobond™that
chemically binds metal contaminants, preventing leaching
underthe most stringent conditions. RMRS has success-
fully deployed the technology at locations throughout the
United States. Envirobond™ can be adapted in a variety
of ways at mining sites, soil washing projects, sediment
removal sites, and others to produce a treated product that
meets criteria foron-site containment, storage, or off-site
disposal. The technology can be adapted for a variety of
waste streams and soil conditions, and binds many types
of heavy metals at high levels of contamination, including
arsenic, barium, chromium, lead, silver, cadmium, sele-
nium, and zinc below the Resource Conservation and
Recovery Act (RCRA) treatment standards. Laboratory
data indicate that the binder is also effective in treating
radionuclides such as uranium, thorium, radium, and stron-
tium.
When desired, the Envirobond™ process can be taken a
step further to produce a solidified monolith, called
Envirobrics™. Envirobric™ has also been developed and
tested for chemical and physical stability, including labo-
ratory, pilot and full scale testing. It resists water, and has
passed a 24-hour immersion test. The Envirobric™ pro-
cess uses off-the-shelf, high throughput equipment, and
is therefore highly cost-effective. It also reduces the bulk-
ing factor and volume of the final waste form to 30%-40%,
which makes it easier to handle and dispose of. This very
simple process does not create secondary waste streams,
nor does it require the addition of heat. Thus, the capital
equipment cost is low and there are no special environ-
mental or safety issues associated with the process.
A2. The Envirobond™ Process
Rocky Mountain Remediation Service's patent pending
Envirobond™ metals treatment process employs a com-
bination of proprietary phosphate materials. The formula-
tion and application may vary somewhat depending on the
concentration and species of metals to be stabilized. The
phosphate compounds provide electrons at the oxygen
sites that form a covalent bond with the heavy metals.The
metal is incorporated into the phosphate structure which
has the ability to immobilize the metal and is not affected
by changes in pH. Chemically, the Envirobond™ phos-
phates form P-O-P chains that have very little steric hin-
drance to internal rotation. The internal rotation of the
phosphate chains allows metals to react with the nega-
tively charged oxygen to form spiral and coiled P-O-P
chains that create complex, stable metallic bonds. The
result is the formation of metallic phosphates that possess
stronger, longer-lasting bonds than the metal-carbonate
bonds found in natural apatite stabilization compounds.
A3. Effectiveness of Envirobond™
In a treatability study conducted last year, mill tailings with
high levels of arsenic, cadmium, chromium, and selenium
were successfully treated (see Figure 1). In this study the
waste was treated for cadmium, chromium, and selenium.
Arsenic was also present at elevated levels. However, the
TCLP level before treatment was not of concern, and as
a result, the Envirobond™ formulation was not directed at
arsenic. The results for these samples are well below the
TCLP RCRA standard for all metals, and also meet the
Universal Treatment Standard for all but chromium, which
is 0.1 ppm above the UTS. Laboratory testing has shown
that Envirobond™ is effective for other RCRA metals,
extremely high levels of lead and other metals of con-
cern such as beryllium, mercury, nickel, and zinc (see
Figure 2).
A4. Cost Analysis
The cost of using Envirobond™ is significantly reduced
when compared to traditional cement-based technologies.
Envirobond™ can be applied using methods that range
from simple agricultural type mixing (i.e., land farming) to
traditional pug mill mixing. Because it can be applied in a
wet or dry form, it can be adapted to many situations to
reduce the cost of equipment and handling.
Treatment on-site is often very cost-effective because it
avoids transportation and disposal costs. If the material
can be used for fill, avoiding the cost of purchasing clean
fill creates even more savings. The major disadvantage to
on-site disposal is that the use of traditional cement, lime,
or other similar additives will add large amounts of mate-
rial to the waste, and some of these treatments are not
effective enough to allow for on-site burial. Some metals
such as cadmium, selenium, or zinc cannot be treated
without adding large volumes of additives. With cement or
54
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lime, the heavy metals may not leach out, but they are still
available to future environmental upsets because they are
not permanently bound to the chemical additives. Forthese
reasons, regulators are not willing to allow wastes to be
disposed of on site, and, in many cases, have insisted that
the waste be excavated and removed. With the superior re-
sults of Envirobond™, regulators will often reconsiderthis
position.
Costs are significantly reduced when compared to cemen-
tation or excavation and hauling. With cementation, the
additional bulking of the waste can easily add a 100% vol-
ume increase. The cost of materials handling and mixing
is also higher. With excavation and hauling, there are ad-
ditional transportation and disposal costs, and the exca-
vated material may need to be replaced with clean fill.
Figure 3 shows the savings that may result when
Envirobond™ is used in place of cement-based technol-
ogy. The cost perton is greatly affected by the type of waste
and by the total number of tons. Generally the cost to use
Envirobond™ is $5 to $30 perton less than cement-based
products.
Figure 1. Mill Tailing Treatability Data (in ppm)
Para-
meter
Arsenic
Cad-
mium
Chro-
mium
Sele-
nium
TCLP
Before
Treat-
ment
0.5
0.18
13
1.95
Enviro-
bond
Treated
Result
#1
N/A
0.11
0.42
0.69
Enviro-
bond
Treated
Result
#2
0.27
0.002
0.92
0.75
Enviro-
bond
Treated
Result
#3
0.55
<0.1
.57
1.4
Enviro-
bond
Treated
Result
#4
0.27
0.21
0.73
0.9
Enviro-
bond
Treated
Result
#5
1.0
0.002
0.85
0.76
Average
of 5
Results
on
Original
Sample
0.5
0.08
0.7
0.9
RCRA
Treat-
ment
Stand-
ard
5
1
5
5.7
UTS
Treat-
ment
Standard
5
0.11
0.6
5.7
Total Metals
Arsenic
Barium
Cad-
mium
Chro-
mium
Lead
Mercury
Sele-
nium
Silver
1920
190
27
570
880
<0.1
200
<10
N/A = Not Available
Figure 2. Laboratory Results for RCRA Metals & Others
RCRA Metals
Total Prior to Treatment (ppm)
As
500
Ba
1180
Cd
27
Lead
40800
Nickel
500
Zinc
500
Beryllium
>5000
TCLP Extract Analysis (ppm)
Sample
Sample
Sample
TCLP LDR Standard
Univerisal Treatment Standard
4.7
4.3
5
5
1.1
0.7
3.1
100
21
<0.002
1.6
<0.002
1
0.11
<0.05
0.3
0.12
5
0.75
9
7.8
4
N/A
11
3
2.6
1.1
N/A
4.3
0.093
0.066
N/A
1.22
N/A = Not Available
55
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Figure 3. Application Methods and Pricing
Method
Ex situ Mixing
In situ Landfarming
Typical Envirobond
Project
$10-$30/ton
$5-25/ton
Traditional Cement
and Silicates
$30-$50/ton
$20-$40/ton
56
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Appendix B Case Studies
(Note: All information in this appendix was provided by the
vendor, Rocky Mountain Remediation Services (RMRS).
Inclusion of any information is at the discretion of RMRS,
and does not necessarily constitute U.S. Environmental
Protection Agency concurrence or endorsement.)
The following are case studies of sites using Envirobond™
to successfully stabilize lead, arsenic, cadmium, and other
RCRA metals.The examples cited include remediation of
a brownfield type of site, a former battery recycling site,
and sludge from a waste water treatment site, which are
typical of the types of sites where Envirobond™ has been
deployed.
B1. In situ Treatment of Mining Waste at
Former Mining Site
The effectiveness of the Envirobond™ process with min-
ing waste and mill tailings has been superb. In addition to
meeting the EPA standards forTCLP, the results of the
TCLP testing have typically met the more stringent UTS.
Figure 4 shows the results from a mining site in Central
City, Colorado. At this site, arsenic, lead, and zinc were the
contaminants of concern, exceeding the EPA's threshold
level. Untreated soil was given the TCLP test, and lead and
zinc exceeded the standards without treatment. Arsenic
was present at 4 ppm, which is just below the RCRA stan-
dard. After treatment with Envirobond™, all three metals
were below the UTS standards. The primary objective of
the project was to stabilize the waste to levels that would
meet the Environmental Protection Agency's (EPA) crite-
ria for releasing the site for development. Equipment in-
cluded a front-end loader, a road grader, a tractor-tiller,
spreading equipment, a water truck, and a sheep's foot
field compactor.
This project demonstrated the versatility of Envirobond™.
Less than 4 wt. %, Envirobond™ and fly ash were added
to the volume of soil, and it was mixed using field equip-
ment. The treated soil was used to form a base for future
construction.The soil was successfully layered, mixed and
compacted to meet the proctor specifications for construc-
tion. The project also demonstrated that it is easy to pre-
Figure 4. On-site Full Scale In situ Treatment of Mine Tailings in Central City
Total Metals (ppm)
TCLP Extract Before Treatment (ppm)
Arsenic
136
0.07
Lead
1270
91.7
Zinc
1270
108
Mercury
5.9
<0.02
TCLP Extract After Treatment (ppm)
Sample 1
Sample 2
Sample 3
Sample 4
Sample 5
Sample 6
Sample 7
Average
TCLP Regulation CFR 261 .24 (a)
Current Univerisal Treatment Standard (UTS)
<0.05
<0.05
O.05
O.05
O.05
<0.05
<0.05
<0.05
5
5
<0.05
<0.05
O.05
O.05
O.05
<0.05
<0.05
<0.05
5
0.37
1.5
1.0
3.9
4.5
4.2
4.7
3.3
3.3
NA
5.3
0.2
0.2
57
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pare Envirobond™ for use in field applications. Finally,
Envirobond™ does not add bulk to the waste, which is
especially important when the waste is transported to a
disposal facility.
Two alternatives were evaluated for remediating the site.
The first was to excavate the waste piles, and other con-
taminated areas, and transport them to a disposal site in
Denver, Colorado. There are two serious disadvantages to
this alternative. The cost of transportation and disposal is
high, and after the waste leaves the site, the owner re-
mains liable for any further contamination that may occur
during transportation, or at the burial site foryearsto come.
The second alternative was on-site treatment. The major
disadvantage to this alternative was that the use of tradi-
tional cement, lime, or other similar additives will add large
amounts of material to the waste, and some of these treat-
ments are ineffective on some types of metals. Some
metals such as zinc cannot be treated without adding large
volumes of additives. With cement or lime, the heavy met-
als may not leach out, but they are still available to future
environmental upsets because they are not permanently
bound to the chemical additives. Forthese reasons, even
at a higher cost, the EPA was inclined to allow only the
excavation and removal of the soil.
The second alternative is much more attractive with a
binder that does not add weight or volume. Use of the
Envirobond™ binding agent adds less than 2 wt.% to the
volume, and when combined with compaction, significantly
reduces the volume. Furthermore, Envirobond™ chemi-
cally binds the metals so that they are not only physically
stabilized, but they are incorporated with a chelating bond
that cannot be penetrated even under severe conditions.
It is not soluble, and the treated soil hardens to form a cap
over the treatment area.
Costs are reduced when compared to cementation or ex-
cavation and hauling. With cementation, the additional
bulking of the waste can easily add a 100% volume in-
crease. The cost of materials handling and mixing is also
higher. With excavation and hauling, there are additional
transportation and disposal costs, and the excavated ma-
terial would have to be replaced with clean fill dirt. All of
these factors add cost that is avoided with Envirobond™.
B2. Treatment of Metals-contaminated
Sludge
The Envirobond™ product can also be used to treat con-
taminated sludge from water treatment plants, evaporation
ponds, waste treatment plants, and mining and milling
operations. Typical contaminants in sludge include cad-
mium, lead, chromium, arsenic, aluminum, zinc, and
barium. The treatment plant in this case study treats wa-
ter from a mining district where the primary metals of con-
cern are cadmium, zinc, and manganese. If the treated
sludge exceeds 1 ppm cadmium, it must be shipped to a
hazardous waste disposal site. The other metals are not
a factor in shipping, but it is desirable to reduce them as
low as possible.
The plant produces between 800 and 1400 cubic yards of
40 wt. % sludge per year. The plant uses a typical co-pre-
cipitation process that generates the sludge. In addition to
the co-precipitation process, the plant treats the sludge to
stabilize the cadmium to a level that will meet the RCRA
TCLP standard for land disposal. (Less than 1 ppm cad-
mium.) Envirobond™ was successfully used to treat this
sludge.The flow sheet forthe process estimates the weight
% of the cadmium, zinc, and manganese to be 0.017 wt.%,
1.9 wt. % and 3.64 wt. % respectively. Envirobond™ has
treated the cadmium in the sludge to below 1 ppm TCLP.
Significant reductions were also seen in the zinc and man-
ganese. (To 16 ppm TCLP manganese and 255 ppm TCLP
zinc). It is estimated that the cost to treat the sludge with
Envirobond™ is about one-half the cost of traditional treat-
ment.
B3. Treatment of Battery Recycle and Dis-
posal Sites
Envirobond™ has been tested for use on two former bat-
tery sites, and is currently in use at one. In both cases, the
levels of lead are similarto the high levels seen in the SITE
demonstration. Those levels are often more than 90,000
ppm total, and as much as 1200 ppm after extraction us-
ing the TCLP test.
There are many sites where spent lead-acid batteries were
reprocessed to recover metals. The batteries were typically
cut open and sulfuric acid was allowed to drain into hold-
ing ponds. Soil contaminated by these ponds was satu-
rated with the lead-containing acid, which accounts forthe
high levels present. The battery casings were then dis-
carded and lead was recovered and smelted into ingots for
reuse in the battery industry.Typical contamination around
battery sites includes surface, groundwater, and soil that
are contaminated with acid and extremely high concentra-
tions of heavy metals such as lead, cadmium, and arsenic.
The lead is typically very leachable due to the high acid
content of the soil.
Treatment of these soils with Envirobond reduces the
leachability of the lead and other metals found in contami-
nated soil at battery sites to the RCRA TCLP standards.
The following table shows the treatability results and ac-
tual site results for a typical battery site. For this project,
the soil was transported to a mixing area of about 1000 sq.
ft. Approximately 1000 ton batches were mixed.The con-
taminated soil was layered in two layers with Envirobond
reagents in the middle. Mixing was accomplished with a
backhoe.The results show that excellent results were ob-
tained, with all batches achieving the RCRA Standard of
5 ppm afterTCLP testing. Figure 5 shows the results from
this site.
58
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Figure 5. Battery Recycle and Disposal Site Results
Contaminant
Lead (Treatability Result)
Lead (Treatability Result)
Field Results (1000 ton batches)
1 000 tons
1 000 tons
1 000 tons
1 000 tons
Total Lead
(ppm)
47800
74800
47000
to 95000
Pretreatment
TCLP (ppm)
956
1160
956
to 1 1 60
Envirobond
Treated
TCLP (ppm)
1.97
1.47
3.7
3.96
2.07
1.54
0.13
RCRA
Standard
(ppm)
5
5
5
5
5
5
5
59
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