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Potential Environmental
Impacts of Dust Suppressants:
Avoiding Another Times Beach
An Expert Panel Summary
Las Vegas, Nevada
May 30-31, 2002
Potential Environmental Consequences of Dust Suppressants
U.S. Environmental Protection Agency
» \ Office of Research and Development
^ | National Exposure Research Laboratory
UNIV
Example Uses
1. Unpaved roads and parking areas.
2. Harvested fields.
3. Temporary disturbed vacant land (construction sites).
4. Earth moving activities (landfills, mining).
Exposure Pathways
A. Atmospheric transport and
transformation.
B. Surface runoff carryi ng suppressants
and/or breakdown products.
C. Uptake of dust suppressant by plants
D. Ingestion of dust suppressant constituents by animals.
E. Ingestion of exposed animals by humans.
F Infiltration conveying suppressants to vadose zone and ground-
water table.
G. Volatilization.
H. Occupational contact by applicators: dermally, orally or by inhalation
I. Potential impacts on soil microbial ecology.
Exposure Pathways (continued)
J. Transport of suppressant particulates by wind erosion to
unintended areas.
K. Off-site runoff of dust suppressant and carrier solvent.
L. Consumption of contaminated groundwater.
M. Downwind drift of spray off-site during application.
N. Ingestion of dust suppressant constituents by humans.
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^eo srAf. E PA/600/R-04/031
* March 2004
Potential Environmental Impacts
of Dust Suppressants:
"Avoiding Another Times Beach"
An Expert Panel Summary
Las Vegas, Nevada
May 30-31, 2002
Edited by
Thomas Piechota, Ph.D., P.E.1
Jeff van Ee2
Jacimaria Batista, Ph.D.1
Krystyna Stave, Ph.D.1
David James, Ph.D., P.E.1
1University of Nevada, Las Vegas
2U.S. Environmental Protection Agency
Sponsored by
U.S. Environmental Protection Agency
Organized by
University of Nevada, Las Vegas
U.S. Environmental Protection Agency
107CMB04.RPT * 03/30/2004
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Notice
The information in this document has been funded by the United States Environmental
Protection Agency under EPA Assistance Agreement #CR829526-01-0 to the University of
Nevada, Las Vegas. It has been subjected to the Agency's peer and administrative review and
has been approved for publication as an EPA document. Mention of trade names or commer-
cial products does not constitute endorsement or recommendation by EPA for use.
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IV
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Executive Summary
A.1 Background
In the past decade, there has been an increased use of chemical dust suppressants such as
water, salts, asphalt emulsion, vegetable oils, molasses, synthetic polymers, mulches, and lignin
products. Dust suppressants abate dust by changing the physical properties of the soil surface
and are typically used on construction sites, unpaved roads, and mining activities. The use of
chemical dust suppressants has increased dramatically due to rapid population growth and
increased emphasis on the need to control particulates in the interest of air quality. In the United
States, there are over 2,500,000 km of public unpaved roads, of which 25% (625,000 km) are
treated with chemical dust suppressants. A critical problem in the arid southwestern U.S. is dust
suppression on land disturbed for residential construction.
Recognizing that it is important to achieve and maintain clean air, the concern that prompted
this report is that application of dust suppressants to improve air quality could potentially have
other adverse environmental impacts. Times Beach, Missouri is a classic example where the
resolution of dust emissions from unpaved roads leads to the creation of a Superfund site. In
1972 and 1973 waste oil contaminated dioxin was sprayed on unpaved roads and vacant lots
for dust control in Times Beach. After realizing the adverse situation that had occurred, the
costs to relocate the residents and clean up the site was over $80 million. Much more stringent
regulations are now in place to avoid another Times Beach; however, there is still concern over
the use of dust suppressants since most products used as dust suppressants are by-products
and their exact composition is unknown.
The purpose of this report is to summarize the current state of knowledge on the potential
environmental impacts of chemical dust suppressants. Furthermore, the report summarizes the
views of an Expert Panel that was convened on May 30-31, 2002 at the University of Nevada,
Las Vegas to probe into the potential environmental issues associated with the use of dust
suppressants.
A.2 Current State of Knowledge
There are several major categories of dust suppressants: hygroscopic salts, organic petroleum-
based, organic nonpetroleum-based, synthetic polymer emulsions, electrochemical products,
mulches of wood fiber or recycled newspaper, and blends that combine components from the
major categories. Dust suppressants are frequently formulated with waste products recycled
from other industries.
Most of the research on dust suppressants has been conducted by industry and has focused on
the effectiveness (or performance) of dust suppressants, that is, the ability to abate dust. Little
information is available on the potential environmental and health impacts of these compounds.
Potential environmental impacts include: surface and groundwater quality deterioration; soil
contamination; toxicity to soil and water biota; toxicity to humans during and after application; air
pollution from volatile dust suppressant components; accumulation in soils; changes in
hydrologic characteristics of the soils; and impacts on native flora and fauna populations.
The major known effects of salts in the environment relate to their capacity to move easily with
water through soils. Water quality impacts include possible elevated chloride concentrations in
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streams downstream of application areas and shallow groundwater contamination. In the area
near the application of salts, there could be negative impacts to plant growth. For organic non-
petroleum based dust suppressants, ligninsulfonate has been shown to reduce biological
activity and retard fish growth. Organic petroleum-based dust suppressants have been shown to
be toxic to avian eggs; however, the leachate concentrations in other studies were low in
comparison to health-based standards. There is also concern with the use of recycled oil waste
that may have heavy metals and PCBs.
A.3 View of the Experts
The expert panel was not able to identify specific concerns on the use of dust suppressants due
to the high amount of variability associated with site conditions, dust suppressant composition,
and application techniques. The experts did agree more attention should be paid to dust
suppressant composition and management. The determination of whether a problem might exist
in any given case, however, must be based on the assessment of site-specific conditions.
The potential impact of dust suppressants on soils and plants includes changes in surface
permeability, uptake by plant roots that could affect growth, and biotransformation of the dust
suppressants in the soil into benign or toxic compounds depending on the environmental
conditions and associated microbiota. Vegetation adjacent to the area where dust suppressants
are applied could be impacted by airborne dust suppressants. This includes browning of trees
along roadways and stunted growth. These effects will vary since different plants have different
tolerances.
The potential impact of dust suppressants to water quality and aquatic ecosystems include
contaminated ground and surface waters, and changes in fish health. Dust suppressants that
are water-soluble can be transported into surface waters and materials that are water-soluble
but do not bind tenaciously to soil can enter the groundwater. Fish may be affected by direct
ingestion of toxic constituents and also by changes in water quality (e.g., BOD, DO, salinity).
A.4 Current Programs/Guidelines
There are no federal regulations controlling the application of dust suppressants; however,
some states have developed guidelines for the use of dust suppressants. These include the
U.S. Environmental Protection Agency (EPA) Environmental Technology Verification (ETV)
program, three state programs in California, Michigan, and Pennsylvania, and a county-level
program in Clark County, Nevada. In Canada, there is the Canada ETV national program.
Although there are no specific regulations in place to control dust suppressant application, it is
noteworthy that existing regulations promulgated under the Resource Conservation Recovery
Act (RCRA), Comprehensive Environmental Response Compensation and Liability Act
(CERCLA), Superfund Amendments and Reauthorization Act (SARA), Clean Water Act (CWA)
and TOSCA restrict the introduction of harmful substances into the environment. Regardless,
there is concern that since no one program addresses the use of dust suppressants, the
enforcement of what is used as dust suppressants could "slip through the regulatory cracks."
VI
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A.5 Path Forward (Recommendation)
The expert panel and organizing committee identified several important issues related to
scientific research and information about dust suppressant, and regulations on the use of the
products. Below is a summary of the major issues and recommendations for each of these
categories:
Scientific issues
• Develop a comprehensive definition of an "effective" dust suppressant that includes the
performance, costs and environmental impacts
• Better understanding of the composition of the dust suppressants and how they change after
application
• Better understanding of dust characteristics and development of methods to assist in the
selection of the most appropriate dust suppressant for a specific site
• Develop a framework (e.g., decision-making tree, expert system) for dust suppressant
selection and assessing potential environmental impacts
• Develop an easily accessible information center, a "clearinghouse", which could help
applicators, regulators, and the public acquire the information about dust suppressants. The
recommended form of this clearinghouse is as a World Wide Web site
• Conduct field experiments that provide additional information on the "effectiveness" of a dust
suppressant with a particular focus on the environmental impacts as well as the performance
of the dust suppressants
Regulations
• Establishing an interagency working group that evaluates the cross media and cross
jurisdictional issues associated with the use of dust suppressants
• Review existing state and federal regulatory databases to determine if the compounds found
in dust suppressants are restricted or prohibited. This should also be done to close regulatory
loopholes that allow entry of unlimited industrial waste into the environment when they are
classified as dust suppressants
• Evaluate whether existing programs such as Federal Insecticide, Fungicide and Rodenticide
Act (FIFRA), RCRA, CERCLA, SARA, CWA, TOSCA and Ecological Soil Screening Level
(Eco-SSL) guidance will serve as good models for the development of risk-based regulations
• Develop a standardized assessment methodology that can be used to estimate soil mass
fractions of dust suppressant constituents at a particular site. An example is provided in the
main part of this report
• Identify standardized environmental tests (e.g., water quality, toxicity) that all dust
suppressants manufacturers would have to perform on their products
VII
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VIM
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Foreword
The purpose of this report is to summarize the current state of knowledge of dust suppressants
and potential environmental consequences. The material presented here is based on
knowledge gained from scientific literature, industry reports, conversations with industry
representatives and regulators, and an expert panel hosted by the University of Nevada - Las
Vegas (UNLV) and the U.S. Environmental Protection Agency (EPA). The expert panel on the
"Potential Environmental Effects of Dust Suppressant Use: Avoiding Another Times Beach" met
on the University of Nevada, Las Vegas, campus on May 30-31, 2002 to consider whether or
not dust suppressants pose risks to the environment or human health and how they should be
used and managed.
Support for the expert panel and preparation of this report was provided by EPA Region 9 who
encouraged the EPA's Office of Research and Development in Las Vegas to consider the use of
dust suppressants and their potential environmental and human health impacts.
The expert panel considered the potential for unintended consequences from dust suppressants
and also if guidelines or regulations on the use of dust suppressants might prevent future
problems. Twenty-six (26) experts from varying disciplines were invited to participate in the
panel. They represented hydrologists, soil scientists, microbiologists, industry, applicators, and
regulators. Several participants had specific knowledge about dust suppressants, but the
majority was selected because of their expertise in a specific discipline. They were asked to
participate in the panel and use their expertise for discussing the current and future use of dust
suppressants in a variety of settings. The specific objectives for this expert panel were to: (1)
review, and add to, industrial and scientific knowledge on the composition of dust suppressants;
(2) interpret the body of knowledge, and identify physical, chemical, biological, and regulatory
issues related to the environmental impacts of dust suppressants; (3) begin to develop a
strategy to assist federal, state, and local agencies in regulating the use of dust suppressants;
and (4) contribute to a report describing the expert interpretations and a strategy for permitting
the use of dust suppressants.
The panel and additional reviewers were asked to review this final report as to whether it fairly
reflects the current knowledge of dust suppressants and their applications, potential problems,
and a path forward to further resolve those problems and other issues. The report reflects a
combination of views of the Expert Panel Organizing Committee and the Expert Panel, and
information from the scientific literature and industry. There were many views presented by the
group of experts and some of them differed. The statements and/or views of individual members
or several members of the Expert Panel are referenced as (Expert Panel 2002), and scientific
literature references use a standard reference form (e.g., Bolander, 1999).
The report is written for several audiences. It is intended to be a guidance document for
regulators at federal, state, and local levels, scientific researchers, and the environmental
community. It serves as a primer to give readers general background information on what dust
suppressants are, how they are used, and what potential regulatory issues arise from their use.
It provides the local-level employee, who has been given the task of learning about dust
suppressants and assessing whether her or his organization should develop regulations, a basic
understanding of the issues and kinds of questions that need to be asked about a particular dust
suppressant application. It also provides information that could ultimately be used to determine
the need for federal regulation of dust suppressants.
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Section 1 of the report provides an introduction and frames the potential problems associated
with the use of dust suppressants. Section 2 provides an overview of dust suppressants, the
various uses, and the current regulations/guidelines. Section 3 summarizes the current state of
knowledge on environmental impacts of dust suppressants from the scientific literature and the
Expert Panel. Section 4 outlines a framework for assessing the potential environmental impacts
of dust suppressants. Finally, Section 5 lists the scientific and regulatory issues that are not
resolved at this time and should be considered if guidelines are to be developed for dust
suppressant use.
A draft version of this report was submitted to all of the 26 Expert Panelists and 10 outside
individuals from government agencies, universities, and industry. A total of 19 individuals
provided comments to the Organizing Committee. All comments were considered, and revisions
were made to strengthen the report. Following is a list of the external reviewers.
Amy, Penny, Ph.D.
Bassett, Scott, Ph.D.
Bolander, Peter
Colbert, Woodrow
Detloff, Cheryl
Franke, Deborah
Johnson, Jolaine, P.E.
Knight, Gaye
Langston, Rodney
Lee, G. Fred, Ph.D., P.E.
Letey, John, Ph.D.
Pickrell, John, Ph.D.
Sanders, Thomas, Ph.D.
Scheetz, Barry, Ph.D.
Spear, Terry, Ph.D.
Starkweather, Peter, Ph.D.
Tyler, Scott, Ph.D.
Wells, Jason
Wierenga, Peter, Ph.D.
University of Nevada, Las Vegas
Desert Research Institute, Reno
U.S. Department of Agriculture, Forest Service
Pennsylvania State Conservation Commission
Midwest Industrial Supply, Inc.
Research Triangle Institute
Nevada Division of Environmental Protection
City of Phoenix, Office of Environmental Programs
Clark County Department of Air Quality
G. Fred Lee Associates
University of California, Riverside
Kansas State University
Colorado State University
Pennsylvania State University
Montana Tech of the University of Montana
University of Nevada, Las Vegas
University of Nevada, Reno
ILS, Inc., ESAT Contractor for U.S. EPA Region 4
The University of Arizona
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Table of Contents
Notice iii
Executive Summary v
Foreword ix
Acronyms xv
Section 1 Introduction 1
Section 2 Background 3
2.1 What are Dust Suppressants? 3
2.2 Uses of Dust Suppressants 5
2.3 Current and Potential Magnitude of Use 5
2.4 How Dust Suppressants Work 7
2.5 How Dust Suppressants are Applied 7
2.5.1 Typical Application Rates of Dust Suppressants 8
2.6 Effectiveness of Dust Suppressants 9
2.7 Current Regulations/Guidelines 10
Section 3 What is Known About Potential Environmental Effects 13
3.1 Overview of Scientific Literature 13
3.1.1 Salts and Brines 13
3.1.2 Organic Non-petroleum Products 13
3.1.3 Organic Petroleum Products 14
3.1.4 Water Quality Impacts from University of Nevada, Las Vegas (UNLV) Study 14
3.2 View of the Experts 15
3.2.1 Potential Factors Affecting Environmental Impacts of Dust Suppressants 15
3.2.2 Unintended Off-site Environmental Impacts 15
3.2.3 Effects on Soils 16
3.2.4 Effects on Air Quality 16
3.2.5 Effects on Flora and Fauna 16
3.2.6 Effects on Surface and Groundwater 17
3.2.7 What can be done to Avoid Another Times Beach? 17
3.2.8 What would be a Significant Concern that would Limit Use? 18
3.3 User and Agency Survey Results 18
Section 4 Framework for Assessing Potential Environmental Effects 19
Section 5 Path Forward - Issues and Potential Solutions 23
5.1 Scientific Issues 23
5.1.1 Better Definition of What is Meant by "Effective" Dust Suppressant 23
5.1.2 Better Understanding of Dust Characteristics as an Air Pollutant 23
5.1.3 Better Understanding of How Dust Suppressants Change After Application 24
5.1.4 Better Definition of Current and Potential Problems/Uses 24
5.1.5 Source of Dust Suppressants and Dilution Water 24
5.1.6 Clearinghouse for Dust Suppressant Information 25
XI
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5.1.7 Risk Assessment and How to Decide What to Test For 26
5.1.8 Example of a Standardized Assessment Methodology 27
5.2 Regulatory Issues 33
5.2.1 Gaps in Existing Regulations 33
5.2.2 Filling the Regulatory Gaps - What's Available in Existing Regulations? 33
5.2.3 What's Next for Regulations? 34
5.2.4 Response to Regulatory Uncertainty - Risk Driven Regulatory Response 36
5.3 Final Recommendations 37
References 39
Appendix A - Literature Review 43
Appendix B - Fact Sheets for Verification Programs and Guidelines 59
Appendix C - Expert Panel Agenda 71
Appendix D - Organizing Committee and Expert Panel 73
XII
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List of Tables and Figures
Table 2-1: Most commonly used dust suppressants (modified from Bolander, 1999a) 4
Table 2-2: Typical dust suppressant use rates for unpaved roads and vacant lands based
on industry data 9
Table 5-1: Relevant EPA and Standard test to be considered in assessing impacts of dust
suppressants 27
Table 5-2: Blank Worksheet A - Estimation of soil mass fraction from suppressant
constituent concentration 28
Table 5-3: Example calculation using Worksheet A 29
Table 5-4: Blank Worksheet B - Estimation of maximum allowable dust suppressant
constituent concentration from risk-based limit in soil 30
Table 5-5: Example calculation of maximum allowable suppressant concentration based
on RCRA 100 ppm action level for Total Petroleum Hydrocarbons (TPH) in soil
as determined using EPA Method 8015 31
Table 5-6: Example calculation of maximum allowable suppressant concentration based
on CERCLA 1 ppb action level for TCDD 32
Figure 2-1: Conceptual model of the various uses of dust suppressants and the potential
environmental consequences 6
Figure 2-2: Topical application of a dust suppressant using a spray hose 7
Figure 2-3: Topical application of a dust suppressant using a spray bar 8
Figure 2-4: Topical application of a dust suppressant using a spray gun 8
Figure 4-1: Framework for assessing the potential environmental impacts of dust
suppressants 19
XIII
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XIV
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Acronyms
APG Application Practice Guidelines
ASTM American Society of Testing and Materials
BOD Biological oxygen demand
CalCert California Environmental Technology Certification program
CCCP Clark County Comprehensive Planning
CERCLA Comprehensive Environmental Response Compensation and Liability Act
COD Chemical oxygen demand
CWA Clean Water Act
DO Dissolved oxygen
Eco-SSL Ecological Soil Screening Level guidance
ETV Environmental Technology Verification program
FIFRA Federal Insecticide, Fungicide and Rodenticide Act
MDEQ Michigan Department of Environmental Quality
MSDS Material Safety Data Sheet
PM Particulate matter
PSCDGRS Pennsylvania Conservation Commission Dirt and Gravel Roads Maintenance
Program
RBCA Risk Based Corrective Action
RCRA Resource Conservation Recovery Act
RO Reverse Osmosis
RTAC Road and Transportation Association of Canada
SARA Superfund Amendments and Reauthorization Act
SIPs State Implementation Plans
TCDD Tetrachlorodibenzodioxin
TCLP Toxicity characteristic leaching procedure
TDS Total Dissolved Solids
TOC Total organic carbon
TOSCA Toxic Substance Control Act
TPH Total petroleum hydrocarbons
TSCA Toxic Substance Control Act
TPH Total petroleum hydrocarbons
TS Total solids
xv
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TSS Total suspended solids
TVS Total volatile solids
USDA U.S. Department of Agriculture
USEPA U.S. Environmental Protection Agency
USDOT U.S. Department of Transportation
UNLV University of Nevada, Las Vegas
VOC Volatile organic compounds
XVI
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Section 1
Introduction
The use of chemical dust suppressants in
the United States is increasing, due to high
rates of population growth in arid regions,
the need to reduce airborne particulate
matter to meet air quality standards, and
increased recognition of the value of re-
ducing erosion and maintenance costs on
unpaved roads. Dust suppressants are used
to control erosion and maintenance costs on
unpaved roads, and to abate fugitive dust in
mining, on construction sites, agricultural
fields, livestock facilities, disturbed vacant
land, landfills, and in steel mills. Materials
used as dust suppressants include water,
salts, asphalt emulsion, vegetable oils,
molasses, synthetic polymers, mulches, and
lignin products. Dust suppressants abate
dust by changing the physical properties of
the soil surface. The mechanisms by which
suppressants abate dust vary with product
type; some form crusts or protective surfaces
on the soil, others act as binding agents
causing particles to agglomerate together,
and some attract moisture to the soil
particles.
Across the United States, over 625,000
kilometers of public, unpaved roads are
treated with chemical dust suppressants
(Midwest Industrial Supply, Inc., personal
communication). In Las Vegas, Nevada, and
Phoenix, Arizona, degraded air quality from
disturbed land and unpaved roads in the
extremely arid environment has led to the
potential for widespread use of dust
suppressants. In spite of the growing use of
dust suppressants, there are no agreed upon
definitions, standards of performance and
almost no regulation of dust suppressant
contents, application rates, or management
practices. Understanding of direct and
indirect effects of dust suppressants on
human health and the environment is limited.
Frameworks for making meaningful cost
benefit analysis of either benefits or risks are
not yet developed.
There is concern that the unexamined use of
dust suppressants might create future
environmental and health liabilities similar to
the problems resulting from dust suppres-
sant use in Times Beach, Missouri in the
1970's. In 1972 and 1973 waste oil contain-
ing dioxin was sprayed on unpaved roads for
dust control in Times Beach (EPA, 1983). A
subsequent flood raised fears that dioxin had
contaminated homes and yards. In 1983, the
2,800 people of Times Beach were
permanently relocated at a cost of
approximately $30 million (EPA, 1988) and
the town was closed. Costs to excavate and
incinerate the contaminated soils were
estimated to be an additional $50 million
(EPA, 1988). To avoid similar contamination
and cost from current uses of dust suppres-
sants, it is important to take an early,
comprehensive look at dust suppressants
and their application and to develop policies,
guidelines, and recommendations for their
use.
Although some programs have been
developed to evaluate dust suppressant
effectiveness and safety, most programs are
voluntary; so most dust suppressant use is
unregulated. Waste products or industrial by-
products are often used as suppressants,
with little examination of the product's
hazardous constituents. Application prac-
tices are also not regulated. The method and
frequency of application and amount of
material applied varies. While risks to human
health and the environment may be taken
into consideration, the primary consideration
driving the decision to use a particular
suppressant is its initial cost. Frequently
reliable performance data does not exist to
determine true cost-effectiveness.
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Several states (California, Michigan, Penn-
sylvania) and counties (Clark County,
Nevada) are developing guidelines for the
use of dust suppressants: where, when and
which suppressant to use for a given
environment. The guidelines (See Section
2.7) developed by the above agencies are
based on limited information and are not
sufficient for developing standard protocol in
determining whether a dust suppressant
should be used. These guidelines were
developed out of a need to prevent adverse
environmental impacts. An extensive testing
program would be needed to develop
standard protocol for dust suppressant use.
Other agencies are interested in developing
regulations for dust suppressant use, but feel
there is little guidance available. Thus, the
overall goal of this report is to summarize the
current state of knowledge on dust
suppressants. The material in the following
sections focuses on the current state of
knowledge about dust suppressants, areas
where information is missing, and proposes
an assessment framework for making
decisions on the use of dust suppressants.
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Section 2
Background
2.1 What are Dust Suppressants?
There is no standard definition of a dust
suppressant. Dust suppressants are
materials used to control particulate matter
emissions from land surfaces. They can
include physical covers (such as vegetation,
aggregate, mulches, or paving) and chemical
compounds. This report focuses on chemical
dust suppressants and one physical cover
(fiber mulch). Chemical products used for
dust suppression fall into eight main cate-
gories, listed in Table 2-1. They include
water, products manufactured specifically as
dust suppressants, natural or synthetic
compounds, and waste or by-products from
other uses and manufacturing processes. In
1991, 75-80% of all dust suppressants used
were chloride salts and salt brine products,
5-10% were ligninsulfonates, and 10-15%
were petroleum-based products (Travnik,
1991). The products are usually provided as
a concentrate. Dilution for application varies
from 1:1 to 1:20 (1 part concentrate to 20
parts water) depending on the specific dust
suppressant, application type, and site
conditions. Since many of the products are
mixed with water, non-aqueous phase liquids
are not commonly used in dust suppressant
formulation (Expert Panel, 2002).
The control of dust emission is closely
related to erosion control, but differs slightly.
In both cases, the goal is to restrict the
movement of soil particles. Dust sup-
pressants are used to prevent soil particles
from becoming airborne. Erosion control
technologies aim to minimize soil movement
on and off a given site. Since erosion control
agents counteract the forces of both wind
and water, they may have different pro-
perties than dust suppressants, which are
used primarily to prevent wind erosion. The
minor differences in the definition and classi-
fication of these materials may become
important as decision makers and regulators
begin to focus on unintended, negative
consequences of these products.
Water alone can be a dust suppressant. It is
commonly used on construction sites and
unpaved roads where the surfaces are dis-
turbed only for short time periods. Water is
probably the most cost effective short-term
solution for dust control (Gebhart et a/.,
1999); however, the cost will vary depending
on climatic conditions influencing water avail-
ability. The application rate is important since
a heavy application may turn the road into
mud destroying the soil's structure and
damage its ability to perform as the sub-
grade. In some areas, reclaimed water is
used for dust control. In these cases, the
quality needs to be considered as well as the
potential for human exposure to reclaimed
water and environmental and wildlife
impacts.
Salts and Brines are the most common type
of dust suppressant used (Travnik, 1991).
Calcium chloride (CaCI2) and magnesium
chloride (MgCI2) are the major products in
this category (Sanders and Addo, 1993).
Calcium chloride is a byproduct of the
ammonia soda (Solvay) process and a joint
product from natural salt brines. Magnesium
chloride is derived from seawater eva-
poration or from industrial byproducts. These
products stabilize the soil surface by
absorbing moisture from the atmosphere, so
it is critical to have sufficient humidity levels
of 20-80% when applying these products
(Bolander, 1999a).
Organic Non-petroleum Products include
ligninsulfonate, tall (pine) oil, vegetable deri-
vatives, and molasses. Ligninsulfonate is
derived from the sulfite pulping process in
3
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the paper industry where sulfuric acid is
used to break down wood fiber. Tall oil is a
by-product of the wood pulp industry recov-
ered from pinewood in the sulfate Kraft
paper process. Vegetable oils are extracts
from the seeds, fruit or nuts of plants and are
generally a mixture of glycerides. Molasses
is the thick liquid left after sucrose has been
removed from the mother liquor in sugar
manufacturing. It contains approximately
20% sucrose, 20% reducing sugar, 10% ash,
20% organic non-sugar, and 20% water
(Lewis, 1993).
Synthetic Polymer Products comprise many
different compounds that promote the bind-
ing of soil particles. The exact composition of
these products is usually not provided in the
Material Safety Data Sheets (MSDS) since
the makeup of the product is confidential
information of manufacturers.
Organic Petroleum Products are derived
from petroleum and include used oils, sol-
vents, cutback solvents, asphalt emulsions,
dust oils, and tars. Petroleum-based pro-
ducts are not water-soluble or prone to
evaporation, and generally resist being
washed away (Travnik, 1991).
Electrochemical dust suppressants are typi-
cally derived from sulphonated petroleum
and highly ionic products. This group of
products includes sulphonated oils,
enzymes, and ammonium chloride. A disad-
vantage of these products is that their
effectiveness depends on the clay miner-
alogy of the site and may only work with
certain types of soils.
Clay Additives are composed of silica oxide
tetrahedra (SiO4) and alumina hydroxide
octahedra (AI(OH)6) (Scholen, 1995). Clay
additives provide some tensile strength in
warm dry climates, however, their tensile
strength decreases as moisture in the soil
increases (Bolander, 1999b).
Mulch and Fiber Mixtures are formulated
from waste wood fibers or recycled
newspapers, a binding agent (for example,
plaster of paris) and a carrier solvent (usually
water). They generally work by forming a
protective layer or crust over the soil surface
instead of by binding soil particulates
together.
Table 2-1: Most commonly used dust suppressants (modified from Bolander, 1999a).
Suppressant Type
Products
Water
Salts and brines
Petroleum-based organics
Non-petroleum based organics
Synthetic polymers
Electrochemical products
Clay additives
Mulch and fiber mixtures
Fresh and seawater
Calcium chloride, magnesium chloride
Asphalt emulsion, cutback solvents, dust oils, modified asphalt
emulsions
Vegetable oil, molasses, animal fats, ligninsulfonate, tall oil
emulsions
Polyvinyl acetate, vinyl acrylic
Enzymes, ionic products (e.g. ammonium chloride), sulfonated oils
Bentonite, montmorillonite
Paper mulch with gypsum binder, wood fiber mulch mixed with
brome seed
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2.2 Uses of Dust Suppressants
Dust suppressants are used on unpaved
roads, road shoulders, construction sites,
landfills, mining operations, military sites,
animal enclosures, vacant lands and agricul-
tural fields (Expert Panel, 2002). Figure 2-1
presents a conceptual model of major dust
suppressant uses. The use of dust sup-
pressants is largely driven by air quality
regulations, but other concerns can also
motivate their use (Expert Panel, 2002). For
instance, transportation agencies may use
dust suppressants to reduce the mainten-
ance on unpaved roads. Private property
owners may use dust suppressants to
reduce nuisance dust.
The selection of a dust suppressant varies
for the different uses. For example,
magnesium chloride and petroleum-based
products would not be suitable for agricultur-
al use because they could affect crops
grown on the fields after application. A fiber
mulch might be more appropriate for use in
agriculture areas. For an unpaved road, the
dust suppressant needs to be more durable
and a fiber mulch would not be appropriate
to use. Instead, a petroleum-based product
may hold up better under traffic conditions.
There is significant regional variation in the
use of dust suppressants (Expert Panel,
2002). In Pennsylvania, the major use is on
unpaved roads. In other parts of the eastern
United States, dust suppressants are used
on landfills, coal fields, steel mills, and
mines. They are also used as temporary
covers on lands that are disturbed for short
periods, such as slopes exposed during road
construction that are eventually revegetated.
In Texas, dust suppressants are used largely
on construction sites with disturbed lands
and haul roads. In Clark County, Nevada,
and other parts of the southwest, 90% of the
use is on disturbed vacant land - land that
has been cleared for residential or commer-
cial development but on which construction
has not yet begun. In some cases, disturbed
land can remain vacant for several years. In
eastern Oregon and Washington, dust sup-
pressants are used on fallow agriculture
fields. The United States Department of Agri-
culture (USDA) Forest Service also uses
dust suppressants on unpaved roads.
2.3 Current and Potential
Magnitude of Use
An important consideration is the current
magnitude of chemical dust suppressant
usage. An unpublished 2001 analysis by the
dust suppressant manufacturer, Midwest
Industrial Supply, Inc., summarized existing
and potential markets for chemical dust
suppressants. Some of the study's key find-
ings are noted below.
1. There are over 2,500,000 km of public
unpaved roads in the United States. It is
estimated that 25% (625,000 km) of
these roads are treated with a chemical
dust suppressant. In addition, there are
over 340,000 km of private unpaved
roads of which 22% (74,000 km) are
treated with a chemical dust suppres-
sant.
2. Globally, there are over 8,000,000 km of
unpaved roads. On the South American
continent, over 2,000,000 km of unpaved
roads is estimated to exist. A small
portion (less than 1%) of these unpaved
roads in South America is currently treat-
ed with dust suppressants.
3. The United States constitutes about 63%
of the global market for chemical dust
suppressants and has a current annual
market value of approximately
$300,000,000.
4. The existing global annual application
rate of chemical dust suppressant con-
centrate is approximately 483,000 tons.
This could increase to over 1,200,000
tons if markets in other regions of the
world (particularly South America) are
developed to the extent of the U.S.
market.
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Potential Environmental Consequences of Dust Suppressants
U.S. Environmental Protection Agency
Office of Research and Development
** National Exposure Research Laboratory
Environmental Sciences Division
Characterization and Monitoring Branch
Example Uses
1. Unpaved roads and parking areas.
2. Harvested fields.
3. Temporary disturbed vacant land (construction sites).
4. Earth moving activities (landfills, mining).
Exposure Pathways
A. Atmospheric transport and
transformation.
B. Surface runoff carrying suppressants
and/or breakdown products.
C. Uptake of dust suppressant by plants.
D. Ingestion of dust suppressant constituents by animals.
E. Ingestion of exposed animals by humans.
F. Infiltration conveying suppressants to vadose zone and ground-
water table.
G. Volatilization.
H. Occupational contact by applicators: dermally, orally or by inhalation
I. Potential impacts on soil microbial ecology.
Exposure Pathways (continued)
J. Transport of suppressant particulates by wind erosion to
unintended areas.
K. Off-site runoff of dust suppressant and carrier solvent.
L. Consumption of contaminated groundwater.
M. Downwind drift of spray off-site during application.
N. Ingestion of dust suppressant constituents by humans.
Figure 2-1: Conceptual model of the various uses of dust suppressants and the potential environmental consequences.
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It is also important to note the potential uses
at a regional scale. Pennsylvania, for exam-
ple, has over 33,000 km of public unpaved
roads that could potentially be treated with
dust suppressants (Expert Panel, 2002). In
Maricopa County, Arizona, the Department
of Transportation applies ligninsulfonate to
92 miles of road shoulders three times a
year (Arizona Department of Transportation,
personal communication). Clark County, Ne-
vada, has 100-200 km of unpaved roads and
approximately 150,000 acres (60,000 hec-
tares) of vacant land in the urban core of the
Las Vegas Valley (James et a/., 1999). Of
these 150,000 acres, 10-20% (15,000-
30,000 acres, or 6,000-12,000 hectares) are
estimated to have a high potential to emit
PM-10 (particulate matter less than 10 urn),
and could be stabilized through physical
cover (vegetation, aggregate) or via appli-
cation of chemical dust suppressants. Clark
County has decided to pave high-use public
roads instead of treating them with chemical
dust suppressants (CCCP, 2001). It was
reported in Pennsylvania that long term envi-
ronmental and maintenance costs are set in
motion by public pressure to pave roads
before a proper road base and drainage sys-
tem is in place. Paved road failures in even
the first year have occurred. However, haul
roads at construction and mining sites are
often treated with chemical dust suppres-
sants.
2.4 How Dust Suppressants Work
Dust suppressants abate dust by changing
the physical properties of the soil surface.
When a dust suppressant is applied the soil
particles become coated and bound toge-
ther, making them heavier. Some products
form a crust on the surface and others
penetrate through the surface. Water and
petroleum-based products form a crust by
agglomerating the soil particles. The forma-
tion of a crust with adequate thickness with
petroleum-based products reduces the
amount of immediate maintenance that is
required on unpaved roads, however, in the
long term, when failures such as potholes
occur, there is no way to repair them using
normal low cost techniques, such as grading.
Unless these roads are milled to return them
to unsealed status, the structural failures get
paved over, again setting in motion the long-
term maintenance and environmental costs
referenced earlier (Expert Panel, 2002).
Many of the synthetic organic materials are
derived from petroleum products and are
mixed with a binding agent that glues the
particles together (Expert Panel, 2002). Salts
absorb moisture from the air and retain it by
resisting evaporation (Foley et a/., 1996). Or-
ganic non-petroleum and synthetic polymer
products act as a weak cement by binding
the soil particles together or weighing down
and agglomerating particles. The electro-
chemical stabilizers work by expelling
adsorbed water from the soil, which de-
creases air voids and increases compaction
(Foley et a/., 1996).
2.5 How Dust Suppressants are
Applied
Dust suppressants are applied either topical-
ly or mixed into the top layer of the soil.
Topical application is with a spray bar on the
back of a truck or through a large hose with
a nozzle on the end (See Figures 2-2 and
2-3). On vacant lands, dust suppressants are
applied topically. On small plots, application
is by hand-directed hoses (Figure 2-2). On
larger properties, application is by truck-
mounted spray bars (Figure 2-3) and modi-
fied water cannons (Figure 2-4). A less
common type of application is when the dry
products (flakes) are spread on the surface
and the product is mixed into the soil (Expert
Panel, 2002).
Figure 2-2: Topical application of a dust
suppressant using a spray hose.
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Figure 2-3: Topical application of a dust
suppressant using a spray bar.
Figure 2-4: Topical application of a dust
suppressant using a spray gun.
Another application method is to mix the dust
suppressant into the travel surface by a
sequence of steps comprising, 1) grading the
road surface to remove a windrow of earth
from the travel lane, 2) application of dust
suppressant, 3) grading the earth windrow
back onto the travel lane and compaction to
maximum density, and 4) a second topical
application on top of the graded earth. Mix-
ing the dust suppressant into the soil is more
difficult, but it tends to last longer since the
product is exposed to more soil particles.
Some dust suppressant vendors have soft-
ware available to make recommendations to
customers based on traffic conditions,
vehicle speed, and other site conditions.
However, a major factor that impacts the
application rate for many situations is the
8
amount of funding available for dust sup-
pression. For instance, a heavier application
often increases the durability of the dust sup-
pressant and reduces the need for repeated
applications (Expert Panel, 2002). Seldom
are analysis made of the soil types, which
may change numerous times on one road in
some geographic areas.
2.5. •/ Typical Application Rates of
Dust Suppressants
Typical liquid application rates vary from 0.3
to 1.0 gallons per sq yard (1.4 to 4.5 liter/m2)
and will depend on site-specific conditions
(e.g., soil type, land use, weather during
application, and weather after application).
For liquid emulsions, dust suppressant con-
centrates are mixed with diluent (usually
water) to give the correct mass application
rate of solids for the desired application. For
example, solids application rates for acrylic
polymer emulsions are usually 0.20 to 1.00
pounds per square yard (0.11 - 0.54 kg/m2)
at liquid application rates of 0.50 to 1.00
gallons per square yard (2.26-4.53 liter/m2).
It is generally better to apply multiple light
applications rather than a single heavy appli-
cation, as the light applications generally
allow for better penetration into the surface
soil and also reduce the fraction of dust sup-
pressant that may run off the target area.
The performance of a dust suppressant is
determined by the mass of applied solids per
unit volume of treated soil. Mass of applied
solids per unit volume of soil will be the
product of the mass application rate, and the
penetration depth of solids into the soil. The
mass application rate of a dust suppressant
is computed as the liquid application rate
times the mass concentration of bulk sup-
pressant in applied liquid.
For example, if the liquid application rate is
0.50 gallon/yd2 (2.26 liter/m2) and the solids
concentration is 1.00 Ib / gallon (0.120 kg/
liter), then the mass application rate of the
dust suppressant is 0.50 gallon / yd2 x 1.00
Ib/gallon = 0.50 Ib/ yd2 (0.271 kg/m2). If the
penetration of the suppressant material was
uniform to a depth of 2 inches (0.05 meters),
then the bulk concentration of the suppres-
-------
sant in the surface layer of soil would be
0.50 Ib/yd2 / (9 ft2/yd2) / 0.167 ft = 0.336 Ib/ft3
(or, 2.71 kg/m2 / 0.05 meters = 5.40 kg/m3).
This bulk concentration is about 1/300 the
mass density of typical soils (-100 Ib/ft3 or
-1,560 kg/m3), so the suppressant solids are
present in the soil at a mass fraction of about
1/300. Mass and liquid rate data for typical
application rates of dust suppressants are
shown in Table 2-2 (James etal., 1999).
Table 2-2: Typical dust suppressant use rates for unpaved roads and vacant lands based on
industry data. English and (SI units).
Liquid application rate
Solids concentration
Solids application rate
Unpaved Roads
Low Rate
0.50 gallon/yd2
0.40 Ib/gallon
0.20 Ib/yd2
(2.26 l/m2)
(0.05 kg/I)
(0.11 kg/m2)
High Rate
1.00 gallon/yd2
1.00 Ib/gallon
1.00 Ib/yd2
(4.53 l/m2)
(0.1 2 kg/I)
(0.54 kg/m2)
10 foot (3.05 m)-wide travel lane:
Topical 1 layer
(solids)
Topical 1 layer (liquid)
Graded 2 layer
(solids)
Graded 2 layer (liquid)
1,173 Ib/lane-mile
2,933 gal/lane-mile
2,347 Ib/lane-mile
5,867 gal/lane-mile
(330 kg/lane-km)
(6,898 l/lane-km)
(661 kg/lane-km)
(13,799 l/lane-km)
5,867 Ib/lane-mile
5,867 gal/lane-mile
11, 733 Ib/lane-mile
11,733 gal/lane-mile
(1,653 kg/lane-km)
(13,799 l/lane-km)
(3,306 kg/lane-km)
(27,596 l/lane-km)
Liquid application rate
Solids concentration
Solids application rate
Vacant Lands
Low Rate
0.50 gallon/yd2
0.40 Ib/gallon
0.20 Ib/yd2
(2.26 l/m2)
(0.05 kg/I)
(0.11 kg/m2)
High Rate
1.00 gallon/yd2
1.00 Ib/gallon
1.00 Ib/yd2
(4.52 l/m2)
(0.1 2 kg/I)
(0.54 kg/m2)
Application rate:
per 100 ft2 (solids)
per 100 ft2 (liquid)
per acre (solids)
per acre (liquid)
2.2lb/100ft2
5.6 gal/1 00 ft2
968 Ib/acre
2,420 gal/acre
(10.7 kg/1 00m2)
(228.1 1/1 00m2)
(1,085 kg/ha)
(22,637 I/ha)
11.1 lb/100ft2
11.1 gal/1 00 ft2
4,840 Ib/acre
4,840 gal/acre
(54.2 kg/1 00m2)
(452.1 1/1 00m2)
(5,426 kg/ha)
(45,273 I/ha)
2.6 Effectiveness of Dust
Suppressants
The majority of research on dust suppres-
sants has been on the effectiveness of the
products, where "effectiveness" reflects the
ability of the product to keep soil particles
on the soil surface when subjected to some
erosive force, such as wind. Effectiveness
varies with type of use, site condition, and
climate. Water has been found to be be-
tween 40% and 85% effective in
suppressing the suspension of soil particles
for short time periods, but not effective over
longer time periods (Thompson, 1990;
Travnik, 1991; Foley et a/., 1996; Kestner,
1989; Cowherd et a/. 1989). Salts are more
effective than water in controlling dust if
sufficient moisture is available (Bolander,
1999a). Ligninsulfonates remain effective
during long, dry periods with low humidity.
They also tend to remain plastic, allowing
reshaping and traffic compaction when
applied to soils with high amounts of clay.
The effectiveness of ligninsulfonates may
be reduced or completely destroyed in the
presence of heavy rain because of the sol-
ubility of these products in water (Bolander,
1999a). Synthetic polymer emulsions in-
crease the tensile strength of clays on
typical roads and trails up to ten times.
Tests have shown that synthetic polymers
applied in wet climates tend to break down if
-------
exposed to moisture or freezing for an
increased time (Bolander, 1999a). Petro-
leum-based products generally resist being
washed away, but oil is not held tightly by
most soils and can be leached away by rain.
Under the right conditions, these products
can remain 90% effective after a year
(Gillesefa/., 1997).
The length of time that a dust suppressant
is effective varies according to variables
such as the type of product, soils, weather,
application rate, and traffic conditions. How-
ever, many manufacturers advertise that the
products will be effective from 6-12 months.
Some products will last up to 24 months
under certain conditions.
2.7 Current Regulations/
Guidelines
At least six programs in the United States
and one in Canada are directly or indirectly
developing, or have developed, guidelines
for dust suppressant use. Appendix B in-
cludes fact sheets for the programs and
following is a summary of the key program
elements. In the United States, there is the
Environmental Protection Agency (EPA)
Environmental Technology Verification
(ETV) program, three states programs in
California (CalCert), Michigan, and Penn-
sylvania, and a county level program in
Clark County, Nevada. In Canada, there is
the Canada ETV national program. The
Canada ETV, CalCert, and EPA ETV
programs are voluntary and available to any
developer/vendor of environmental technol-
ogy, including dust suppressants. All three
verification programs (ETV, CalCert, and
Canada ETV) were created by partnerships
between regulatory environmental agencies
and either the private sector or non-profit
organizations, with an emphasis on the
performance claims and some environmen-
tal tests of the products. Other programs
that are ancillary to dust suppressants are
those that provide specifications for the use
of snow and ice control products such as
the Pacific Northwest Snowfighters
(www.wsdot.wa.gov/partners/pns/default.htm).
10
The testing program in Pennsylvania was
developed by joint efforts of conservation
interests, academia and industry and, is
used, for all materials, including suppres-
sants, for projects funded by the Dirt and
Gravel Roads Maintenance Program under
the State of Pennsylvania Conservation
Commission (PSCDGRS, 2003). The strin-
gent specifications require product testing
by a certified lab and manufacturer guaran-
teed product uniformity, delivery, application
and cure. Results in the program have been
so positive, and reception by industry so
strong, it has been used voluntarily by
others. The Michigan Department of Envi-
ronmental Quality created specific regula-
tions for the application of oil field brine as a
dust suppressant (MDEQ, 2000). Clark
County, Nevada has issued detailed interim
guidelines for the use of dust suppressants
on disturbed lands (CCCP, 2001). The
guidelines were drafted by a working group
composed of air and water quality profes-
sionals from state and local agencies, as
directed by the Clark County Commission-
ers.
In all three voluntary certification programs
and in the Pennsylvania Dirt and Gravel
Road regulations, it is the responsibility of
the technology vendor/developer to provide
sufficient performance data and documenta-
tion to support the claims of the technology
under consideration. While the other pro-
grams do not specify what data should be
provided to support the technology claim,
the Environmental Protection Agency (EPA)
ETV and the Pennsylvania programs note
specific tests that have to be performed to
evaluate the environmental impacts of the
products under consideration. In the EPA
ETV, ETV Canada, and CalCert voluntary
programs, scientists and engineers from
regulatory agencies, universities, research
laboratories, and the private sector examine
the supporting documentation for product
verification. However, ETV Canada main-
tains a list of approved expert entities (e.g.
universities, private consultants) to be used
to conduct tests to support the verification.
An agreement is reached with the vendor/
developer regarding the expert entity to be
used in the technology verification process.
-------
In the case of Pennsylvania, the data sup-
porting the claim, issued by EPA certified
labs, are evaluated by the State Conser-
vation Commission for authenticity. All three
voluntary verification programs, as well as
Pennsylvania's, issue a report or certificate
as proof of verification. Only the Canada
ETV and the California CalCert programs
require renewal of the verification after three
years.
Michigan's regulations for brine application
as a dust suppressant do not specify any
specific test methods. Instead, it establishes
acceptable application rates and methods,
and types of areas where it can and cannot
be applied. It also requires the property
owner or contractor to maintain detailed
record keeping of the specific locations,
amount, and source of brine applied. Clark
County, Nevada guidelines specify types of
areas where the application of specific dust
suppressants are discouraged. In addition,
they contain recommendations on the types
of suppressants, dilution, and application
rates to be used in different types of dust
control areas (e.g. roads, construction
sites). In general, the Clark County guide-
lines discourage the application of products
known to potentially contain specific
pollutants near lakes, streams, channels,
and flood control channels.
The EPA ETV program requires acute and
chronic toxicity tests (EPA/600/4-90/027F
and EPA/600/4-91/002), and analyses of
biological oxygen demand (BOD), chemical
oxygen demand (COD), volatile organic
compounds (VOC), toxicity characteristic
leaching procedure (TCLP) [EPA Method
1311], inorganics/metals (EPA 601 OB),
semi-volatile organics (EPA 8270D), volatile
organics (EPA 8260B), pesticides/herbi-
cides (EPA 8270D), and PAHs. The
Pennsylvania program requires bulk anal-
ysis of products using EPA SW-846 tests
(originally designed for testing RCRA
wastes), leach analysis by EPA Method
1312 (includes metals, volatiles, and semi-
volatiles), 7-day survival and growth test for
rainbow trout and Ceriodaphinia dubia,
BOD, and COD.
In addition to the programs noted above, the
United States Department of Agriculture
(USDA) Forest Service is developing the
"Forest Service Specifications for the Con-
struction of Roads and Bridges" that will
have new requirements for dust suppres-
sants. These requirements will include a
certificate that states that the dust suppres-
sant meets the chemical requirements of
the Pacific Northwest Snowfighters, that a
toxicity test (ASTM E 729) be submitted,
and that the pH of the product be on the
certificate as well.
11
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12
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Section 3
What is Known About Potential Environmental Effects
The majority of research on dust suppres-
sants has been by industry and has focused
on the effectiveness (or performance) of dust
suppressants to abate dust, however, little
information is available on the potential envi-
ronmental and health impacts of these
compounds. The numerous pathways of
exposure to dust suppressants for humans,
flora, and fauna and how suppressants may
migrate through the environment to po-
tentially sensitive recaptors are shown in
Figure 2-1. Impacts will depend upon their
composition, application rates, and interac-
tions with other environmental components.
Potential environmental impacts include: sur-
face and groundwater quality deterioration;
soil contamination; toxicity to soil and water
biota; toxicity to humans during and after
application; air pollution; accumulation in
soils; changes in hydrologic characteristics
of the soils; and impacts on native flora and
fauna populations.
This conceptual model and all of the poten-
tial pathways and receptors of concern were
presented to the expert panel for their
consideration. Following is a brief summary
of the literature on known potential effects of
dust suppressants. A complete description of
the studies is provided in the literature re-
view presented in Appendix A. The views of
the Expert Panel on potential environmental
effects of dust suppressants are then pre-
sented Section 3.2.
3.1 Overview of Scientific
Literature
Although there are several noteworthy
studies on the effects of dust suppressants
to water quality, plants, and fish, the majority
of the studies have focused on salts and
brines, ligninsulfonates, and a few organic
petroleum-based products.
3.1.1 Salts and Brines
The major known effects of salt in the
environment relate to its capacity of moving
easily with water through soils. Water quality
impacts include possible elevated chloride
concentrations in streams downstream of
application areas (Demers and Sage, 1990)
and shallow groundwater contamination
(Heffner, 1997). In the area near the applica-
tion of salts, there have been negative
impacts to the growth of fruit trees (RTAC,
1987), pine, poplar, and spruce (Foley et a/.,
1996, Hanes et a/., 1976, and Hanes et a/.,
1970), and alterations in the plant nutrition
due to increases in the osmotic pressure of
soils (Sanders and Addo, 1993). Chloride
concentrations as low as 40 ppm have been
found to be toxic to trout, and concentrations
up to 10,000 mg/L have been found to be
toxic to other fish species (Foley et a/., 1996,
Golden, 1991). Salt concentrations greater
than 1,800 mg/L have been found to kill
daphnia and crustaceans (Sanders and
Addo, 1993), and 920 mg/L of calcium
chloride has been found to be toxic to daph-
nia (Anderson, 1984).
3.1.2 Organic Non-petroleum
Products
The majority of research in this category has
focused on the impacts of ligninsulfonate.
The toxicity of ligninsulfonates to rainbow
trout and other biota has been investigated
(Heffner, 1997). The 48-hour LC50 (concen-
tration of ligninsulfonates which would be
lethal to 50 percent of the tested population
within 48 hours) value for ligninsulfonates
was found to be 7,300 mg/L (Roald, 1977a
and 1977b). A mortality of 50% was
achieved for rainbow trout exposed to 2,500
mg/L ligninsulfonate for 275 hours. For
concentrations equal to or higher than 2,500
13
-------
mg/L, rainbow trout showed loss of reaction
to unexpected movements, rapid and
irregular breathing, and finally loss of co-
ordination before death. It has been found
that calcium and sodium ligninsulfonate
negatively affect the colon of guinea pigs
causing weight gain and producing ulcer-
ation in those animals (Watt and Marcus,
1976).
High levels of ligninsulfonate in water bodies
have high coloring effects, increase bio-
chemical oxygen demand, reduce biological
activity, and retard growth in fish (Raabe,
1968, Heffner, 1997, RTAC, 1987, Bolander,
1999a, Singer et a/., 1982). However, lignin-
sulfonate compounds do not impact seed
germination in the areas where applied
(Singer et a/., 1982).
3.1.3 Organic Petroleum Products
Potential environmental impacts are highest
from organic petroleum products. The chem-
ical characteristics of the oil deposit from
which the petroleum product originated,
results in varied impacts with the potential for
high levels of heavy metals from specific oil
deposits. Several studies have shown that
waste oils may contain known toxic and car-
cinogenic compounds (e.g. PCBs); therefore
EPA prohibits the use of these materials
(RTAC, 1987; Metzler, 1985, and USEPA,
1983).
The accidental introduction of a petroleum-
based dust suppressant (Coherex) into a
stream in Southern Pennsylvania affected
fish and benthic macroinvertebrate com-
munities and killed a large number of fish
(Ettinger, 1987). Organic petroleum-based
products have also been found to be toxic to
avian mallard eggs. When the eggs were
exposed to a concentration of 0.5 /^L/egg,
60% mortality was observed by 18 days of
development (Hoffman and Eastin, 1981).
3.1.4 Water Quality Impacts from
University of Nevada, Las
Vegas (UNLV) Study
A recent UNLV study, funded by several
local agencies in the Las Vegas Valley,
14
generated preliminary data highlighting the
potential of the major dust suppressant cate-
gories. The research focused on the quality
of urban runoff and on the changes in the
chemical composition of soils where sup-
pressants were applied (Piechota et a/.,
2002 and Singh etal., 2003). Rainfall events
were simulated on the dust-suppressant
treated plots and the changes in soil com-
position and the quality of the runoff
emanating from the plots were examined.
In the study, a site was graded and divided
into several individual plots. Each plot was
2.4 meters x 2.4 meters. Six categories of
dust suppressant (11 individual products)
were topically applied to the plots by local
dust suppressant applicators. The dust
suppressants applied included acrylic
polymer emulsion, ligninsulfonate, petro-
leum-based organic, non-petroleum based
organic, fiber mulch, and magnesium chlor-
ide salt. Rainfall was simulated using water
treated by a reverse osmosis (RO) system.
The water supply characteristics were
designed to be similar to those of the rainfall
in the Las Vegas Valley. An approximate
rainfall of 20 mm was generated for a 1-hour
period. The first five gallons of runoff
emanating from the plots were combined to
form a composite sample that was divided
into aliquots, preserved, and analyzed for
chosen parameters. In addition, the top two-
inches of soil from each plot were sampled
after the rainfall events to determine remain-
ing levels of different compounds. The soil
samples were leached using the EPA
Synthetic Precipitation Leaching Procedure
(Method 1312). Parameters evaluated in the
runoff and soil leachate include 67 toxic
volatile and 76 semi-volatile organic com-
pounds, organic pesticides, PCBs, 11
metals, nutrients, biochemical oxygen de-
mand (BOD), total solids (TS), total volatile
solids (TVS), total suspended solids (TSS),
total dissolved solids (TDS), turbidity, total
organic carbon (TOC), pH, alkalinity, chem-
ical oxygen demand (COD), hardness,
nitrate, ammonia, phosphate, sulfide, sulfate,
cyanide, chloride, and coliform bacteria.
The results show that petroleum-based
products had a higher number of potentially
-------
toxic contaminants with concentrations
greater than the control plot, followed by
acrylic polymers and ligninsulfonate. Magne-
sium chloride presented the lowest number
of contaminants with concentrations greater
than the control. The majority of the dust
suppressants created a surface that is more
impermeable than the natural soil surface.
This increased the runoff volume similar to
that emanating from a developed land
surface.
Although several compounds that affect
water quality have been detected in the
runoff of plots to which dust suppressants
were applied, this information alone should
not be used to evaluate the impacts of dust
suppressants to water quality. The data
generated in this study and others should be
combined with information on dust sup-
pressant effectiveness, the frequency of
application, proximity to water bodies, and
cost to thoroughly evaluate the feasibility of
using these compounds when water quality
is a concern.
3.2 View of the Experts
This section summarizes the expert panel
views on potential environmental impacts of
dust suppressants, presented during the
panel discussions. It is problematic to attri-
bute specific views to a specific expert;
therefore, the major points of consensus are
noted below and collectively these represent
the views of the experts as captured in the
Expert Panel and through their review of the
document.
3.2.1 Potential Factors Affecting
Environmental Impacts of Dust
Suppressants
On-site and off-site environmental effects of
dust suppressant application depend on
many factors including the physical charac-
teristics of the suppressant, its chemical
composition, concentration, the form it takes
when it migrates, soil composition, and the
climate conditions during and after appli-
cation. From all the aforementioned factors,
the lack of knowledge on the chemical com-
position of the suppressants is of critical
importance to the evaluation of the environ-
mental impacts of these compounds.
There is a need to improve information about
the chemical composition of suppressants.
Although Material Safety Data Sheets
(MSDS's) for suppressants include the major
components of the dust suppressants, they
do not always include adequate details on
toxic compounds that may be present and
are of environmental concern. Because the
vast majority of compounds used as dust
suppressants are waste products from the
manufacturing industry, their chemical com-
position is often unknown and complex and
may vary widely for each batch. Organic
suppressants sometimes contain surfactants
or foaming agents that can cause environ-
mental effects. One applicator cited an
instance in which they unexpectedly found
benzene, a carcinogenic hydrocarbon, in an
off-spec water-based paint product sold as a
dust suppressant. The compound was
detected in tests performed on the dust
suppressant prior to application. However,
testing of the dust suppressants prior to
application is expensive and not a common
practice.
3.2.2 Unintended Off-site
Environmental Impacts
Dust suppressants can potentially affect the
environment beyond the application site.
Overspray during application affects land,
plants and fauna adjacent to the site. In
addition, dust suppressants can be trans-
ported onto adjacent lands by surface flow or
air. Material can be spilled from application
trucks during transport to or from the
application site, and commonly during off-
loading from tankers to distributor trucks. It is
a concern that trucks applying suppressants
to roads have been observed to continue
spraying when they cross bridges, resulting
in dust suppressants being sprayed directly
into streams below.
After the application of the dust sup-
pressants it must be borne in mind that
suppressants attached to soil particles
covered with dust suppressants can be
transported due to wind or erosion to off-site
15
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areas. In Pennsylvania it has been observed
that a farmer's machinery kept under an
open-sided shelter was completely rusted
from salts carried on the dust from a nearby
brine application demonstration.
Humans who are on the site during appli-
cation (e.g., applicators) or after application
could also come in direct contact with the
dust suppressant. Road applications bear
the additional exposure of suppressant
product becoming embedded under the skin
of errant runners or cyclers. In addition, there
is the potential for deleterious effects of
pumping water from remote streams to con-
struction sites for dust control. One instance
was reported in Pennsylvania where the
contractor pumped a stream dry.
3.2.3 Effects on Soils
Dust suppressants may cause undesired
dissolution of some soil constituents. In the
simplest case, even water used as a sup-
pressant may cause chemical dissolution of
compounds bound to soil particles. In soils
from arid regions, which have high salt con-
tent, water used as a suppressant can
mobilize the salts, increasing the salt
concentration in nearby waterbodies or
groundwater. In more complex scenarios,
the chemical constituents of the suppressant
can react with and leach toxic components
out of the soils at the application site. The
issue of leaching is particularly relevant
where dust suppressants are used on coal-
fields, landfills, and mine tailings piles, which
may contain hazardous material.
The constituents of the suppressants may be
taken up by plant roots and systemically
affect plants. In addition, soil microorganisms
may biotransform the suppressants into
benign or more toxic compounds depending
on the environmental conditions on the site
of application.
The application of dust suppressants will
have secondary effects on the charac-
teristics of soils to which suppressants are
applied including a decrease of surface
permeability. Depending on precipitation, the
change in surface permeability can lead to
16
increased runoff from the site to adjacent
sites and decreased soil moisture. Changes
in surface flow can then change patterns of
erosion on and off the application site.
3.2.4 Effects on Air Quality
Dust suppressant use can affect air quality
characteristics in a number of ways. In arid
areas, for example, the use of water may
add moisture to air fostering the proliferation
of microorganisms. Dust suppressants that
adhere to soil particles can be re-entrained
into the air with strong winds, potentially
adding contaminants to the air in addition to
particulate matter. It is noteworthy that dust
suppressants have little efficacy at suppres-
sing small respirable dust that have the
potential to be inhaled directly into lung
parenchyma and cause lung disease (Reilly
et a/., 2003). Dust suppressants are gener-
ally used to comply with PM10 regulations
and improve visibility; but could be poten-
tially harmful since smaller dust particles
(less than 10 /^m) can be inhaled. Lastly,
some dust suppressants may have volatile
organic compounds in the products that may
be dispersed into the air when the product is
applied. This is a particular concern in the
formation of ozone.
3.2.5 Effects on Flora and Fauna
Dust suppressant application is not limited to
the soils on the site. Since dust suppres-
sants are generally applied over the surface,
any vegetation or fauna on the site, including
soil microorganisms, may also come into
direct contact with the suppressant. Appli-
cation of dust suppressants, especially
magnesium chloride, has been associated
with the browning of trees along roadways
and stunted vegetation growth in forestlands.
Effects vary, because different plants have
different tolerances.
Aquatic ecosystems are affected by direct
contamination from spills or runoff from off-
site applications of dust suppressants. Fish
may be affected by direct ingestion of toxic
constituents or their degradation products.
They are also sensitive to increased salinity
resulting from salts and brine applications.
-------
Dust suppressants that result in an increase
in biochemical oxygen demand (BOD) can
result in decreased DO concentrations in
nearby streams, which may affect fish health
and survival. Dust suppressants that affect
macroinvertebrates could cause a decrease
in food supplies for fish. Dust suppressants
that result in increased suspended solids
concentration, either directly or indirectly, via
erosion, can potentially degrade aquatic
habitat. At the micro level, suppressants can
potentially be toxic to soil and water micro-
organisms.
There is a chance that reproductive effects
for fauna could also be found in these areas.
An example of adverse impact of dust sup-
pressants in animals relates to using finely
chopped asphalt in feedlots to suppress
dust. With time, the animals started having
convulsions and high levels of lead were
found in their blood. When the animals were
moved to another feedlot, the symptoms
were reduced.
3.2.6 Effects on Surface and
Groundwater
Dust suppressant use can potentially affect
both surface and groundwater. Spills directly
affect surface water and can impact ground-
water depending on site characteristics. Dust
suppressants that are water-soluble can be
transported into surface waters and mater-
ials that are water-soluble but do not bind
tenaciously to soil can enter the ground-
water. If the soil surface is not bound
together well (i.e., chlorides, lignin) or if the
rain event is extreme, dust suppressant
treated soil particles can be carried by over-
land flow into streams, rivers, and ditches.
Sedimentation and uptake of soil particles
could adversely affect aquatic or marine life,
if sufficient numbers of treated particles have
significant and mobile concentrations of haz-
ardous compounds. Settled particles can
also change the composition of the ecolo-
gical community and the dominant species
(Sanders et a/., 2003).
3.2.7 What can be done to Avoid
Another Times Beach?
To further engage the experts and to work
through the scientific and policy issues
associated with dust suppressant use, the
experts were posed the above question and
asked to respond individually. Following is a
compilation of the responses.
Primarily, materials that fail existing reg-
ulatory thresholds for toxicity and those
containing FIFRA (Federal Insecticide,
Fungicide, and Rodenticide Act), TSCA
(Toxic Substance Control Act), and RCRA
(Resource Conservation and Recovery act)
regulated compounds should not be used as
dust suppressants. Chlorinated compounds
and materials containing any paints should
be carefully evaluated if used in a dust sup-
pressant. Food products (e.g. soy oil,
molasses) could be used, when possible, for
they are likely to contain less toxic com-
pounds than the industrial materials and
waste products currently used as dust sup-
pressants. Natural products are likely to
biodegrade in the environment and therefore
toxic effects are expected to be minimal.
However, the make up of these products
needs to be considered since some bio-
degradable products can be toxic before
degradation occurs.
Application of all types of chemical dust
suppressants should not be ruled out or
permitted under all conditions. Instead,
guidelines should be drafted to indicate
where specific dust suppressants should be
applied. Application of chemical dust sup-
pressants should be avoided near sensitive
environments, near water bodies and fractur-
ed rock, in areas with a shallow groundwater
table, and other areas where water could
quickly reach the saturated zone. Site-
specific characteristics should be considered
when approving the use of dust suppres-
sants. All of these recommendations would
require the screening of suppressants via a
certification program, and a proper monitor-
ing program of product make up over time.
This would eliminate suppressants that do
not meet expected standards. Alternatively,
the number of dust suppressants to be
17
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applied could be limited to specific types;
that would facilitate regulation and monitor-
ing of the environmental impacts.
The public perception of toxicity may be an
important component of the acceptance of
dust suppressants as a dust abatement
technology notwithstanding the actual threat
the suppressant may pose. Factors such as
the smell and the visual impact of dust
suppressants should be considered. Finally,
information on environmental impacts and
effectiveness of dust suppressants should be
used together when determining the type of
suppressant to be used. If only environ-
mental concerns are used as guidance to
select dust suppressants, one could end-up
with the most environmentally friendly sup-
pressants instead of the best suppressant for
the application with the least potential
environmental risks. Before adopting new
regulations, the advantages (e.g., improved
air quality) and disadvantages (e.g., con-
taminated soils) associated with dust
suppressant should be considered in risk
management analysis.
3.2.8 What would be a Significant
Concern that would Limit Use?
The Expert Panel was also presented with
the above question on what would constitute
a concern for them. The following items
would cause the experts to limit the use of
dust suppressants:
1. Data indicating a potential ecological
impact (e.g., plant stress, isolation of
animal communities, habitat disruption).
2. Data indicating carcinogens, toxins in
levels that would cause negative impacts
in human health.
3. Industrial waste by-product containing
potential toxic contaminants.
4. Suppressant containing significant
amounts of products regulated under
FIFRA, TSCA, and RCRA.
5. Potential or observed negative impacts
to adjacent landowners.
3.3 User and Agency Survey
Results
To further probe into the current practices
used for dust suppressant selections,
several agencies and dust suppressant
applicators were asked what characteristics
in a dust suppressant they felt were
important when deciding on the use for a
particular situation, and what other factors
influence their decisions. The main
considerations include:
• Environmental impacts, especially near
detention basins/waterways
• Toxicity such as LC50 test of dust
suppressant on fish
• Cost of dust suppressant per acre
• Application costs
• Warranty time and durability
• Availability of product
• Type of equipment needed to apply
product
• Penetration characteristics
• Past history of dust suppressant use
• Traffic impacts (i.e., different products for
different conditions)
• Long term maintenance costs
• Category of dust suppressant
18
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Section 4
Framework for Assessing Potential Environmental Effects
To make decisions about dust suppressant
use, managers must evaluate the potential
level of concern that use will generate. The
level of concern about a given dust
suppressant depends on a number of site-,
use-, and composition-specific factors.
These factors are highly variable and infor-
mation about many of them is uncertain. The
diagram shown in Figure 4-1 presents a
framework for assessing the level of concern
about the use of a particular dust sup-
pressant. This is not meant to be a
comprehensive decision-tree model. Instead,
it outlines it identifies the type of information
needed to evaluate the product. It also
summarizes the relationship between the
purpose of application, type of dust sup-
pressant, site conditions, and level of
concern. This is intended for managers
and/or policy-makers who would use this
framework to make a decision about the use
of a particular dust suppressant on a specific
site. This would guide the person on what
information would need to be collected for
each of these categories specific to the sup-
pressant and the site in question. An
explanation of the diagram from the bottom
(endpoint) to the top is provided below.
Purpose and
Method of
application
Source and
Type of dust
suppressant
Rate of
'suppressant-
application
\
Concentration Type of
of constituents Constituents
Application Site
-------
To determine the level of concern about a
given use, both the effects of exposure of the
suppressant on a range of ecosystem com-
ponents and the significance of those effects
must be considered. If a suppressant applied
to a given site were carried off the site and
into an adjacent stream, for example, the
level of concern would depend on the effect
of that suppressant on the aquatic ecosys-
tem - an algal bloom caused by an input of
phosphorus, for example - and the signi-
ficance of that effect. The same effect could
be critical in one system and insignificant in
another. An algal bloom might be unac-
ceptable in a water body used for swimming
but unremarkable in a wastewater treatment
plant outfall. The significance of the effect
might also be determined by comparing the
effect of use with the effect of not using the
suppressant. Any decision to use or not use
a suppressant should be based on an
assessment of benefits and risks (Expert
Panel, 2002).
The effects of dust suppressant exposure on
and off the application site are a function of
the site characteristics, amount of exposure
the different ecosystem components receive,
and climatic conditions at the site. Site
characteristics such as topography, soil
texture and chemistry, groundwater flow
path, vegetation and wildlife types, and
distribution set the parameters for environ-
mental responses to dust suppressant
exposure. A basic set of ecosystem com-
ponents whose response to the dust
suppressant should be evaluated, include
air, soil, water, soil microbes, aquatic
organisms, vegetation, fauna, and people
(Expert Panel, 2002). Different categories
might be more or less important at different
sites. One site may contain species sensitive
to a particular compound while another may
not. Site characteristics can also affect the
ecosystem response to a suppressant.
Alkaline soils may buffer acidic constituents
of a suppressant. Dense vegetation may
take up excess nutrients in organic
suppressants. Soil microbes may break
down potentially toxic suppressant con-
stituents. Climatic conditions at the site,
including the precipitation regime, wind
exposure, and temperature, also affect the
20
response of ecosystem components to the
suppressants. Dust suppressant constituents
might react differently under different
moisture and temperature conditions, for
example. The degradation rates of some
constituents of dust suppressants may vary
with exposure to ultraviolet radiation. The
ecosystem response also depends on the
amount of exposure to a given suppressant
constituent received by the ecosystem
component. The response of any given eco-
system component may be non-linear, or
involve thresholds.
The amount of exposure received by a given
ecosystem component to a given suppres-
sant constituent depends on the rate at
which it is applied to the site (loading rate)
and the transport of constituents to each
ecosystem component. The constituent load-
ing rate depends on the rate at which the
suppressant is applied, the type of
constituents in the suppressant, and their
concentration. Once the suppressant is
applied to the site, its constituents may
migrate within the site, from the soil surface
to the sub-surface, for example, or to the
groundwater or into the air. The pathways
and rate at which any given constituent
moves within the site or off the site are a
function of the site characteristics, climatic
conditions, and the characteristics of the
constituents. The amount of precipitation a
site receives affects the transport of water-
soluble constituents, as do its topography,
soil, and geologic characteristics. Some
constituents are more mobile than others.
They may be more soluble, or more likely to
be volatilized. Depending on soil chemistry,
some may be adsorbed to soil particles.
Constituents may be transformed after appli-
cation, reacting chemically with each other or
with components at the site, or being
degraded.
The rate of suppressant application depends
on the purpose and method of application.
The purpose of application - to stabilize
disturbed vacant land or agricultural land or
to reduce the dust generated from travel
over unpaved roads, for example - together
with specific site characteristics and climatic
conditions, determine the amount and fre-
-------
quency at which the suppressant is applied.
The purpose and site characteristics also
influence the method of application. If the
surface to be stabilized is not expected to be
disturbed, the suppressant may be applied
topically. If the surface must withstand
vehicle traffic, the suppressant may be
mixed into the soil by grading.
The type and concentration of constituents in
the suppressant are a function of the type
and source of the suppressant. Dust
suppressants can be water, brines, lignin-
sulfonates, petroleum-based products, or
other types, as discussed in Section 2.1.
Dust suppressants may contain components
other than the primary suppressant,
depending on the source of the suppressant
(Expert Panel, 2002). Most suppressants are
derived from waste materials from manu-
facturing processes. Even the source water
(e.g., reclaimed water, groundwater) may
contain additional constituents. The com-
position of the suppressant, together with the
rate of application determines the amount
(mass) of each constituent applied to the
site.
21
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22
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Section 5
Path Forward - Issues and Potential Solutions
There are a significant number of "data
gaps" that need to be filled to more
adequately address environmental and regu-
latory issues (Expert Panel, 2002). Research
questions range from "What is the national
scale of the problem?"; "How much is being
applied and where?"; "What tests should one
run to determine the chemicals leached into
soil and the biological impacts of dust sup-
pressants after they are applied?" These
types of questions must be answered before
a decision can be made about whether or
not more federal regulation is needed. This
section focuses on the scientific and regula-
tory issues, and then provides suggestions
for a path forward.
5.1 Scientific Issues
5.1.1 Better Definition of What is
Meant by "Effective" Dust
Suppressant
As noted earlier, there is no standard defin-
ition of a dust suppressant. Current usage of
the term "dust suppressant" implies that it
can be any chemical formulation applied to
the ground to control emission of dust.
Furthermore, the term "effective" dust sup-
pressant is not well defined. Currently, the
definition of an effective dust suppressant
focuses on the ability (efficiency) of the
product to suppress particulate matter from
becoming air borne over a period of time
(Expert Panel, 2002). To support this, Indus-
try has developed data on the performance
of dust suppressants on various types of
land surfaces (see Literature Review in
Appendix A).
A more comprehensive definition of an
effective dust suppressant is needed to
consider the overall impacts of using the
products. A comprehensive definition of an
"effective" dust suppressant might consider
the following (Expert Panel, 2002):
1. The efficiency and durability of the pro-
duct
2. The costs and benefits associated with
the use of the product
3. The potential environmental impacts
In making the determination of what dust
suppressant to use, it is also important to
select the proper dust suppressant based on
soil characteristics. Soil characterization
tests are not always performed on sites
when selecting a dust suppressant; however,
several experts were asked what tests they
would recommend. Recommendations in-
cluded gradation tests (AASHTO T-11 and
T-27), plasticity tests (AASHTO T-89 and T-
90), pH tests of the soil, tests for the ability of
soil to attract of bind a particular dust
suppressant, particle size distribution, mois-
ture content, and a visual survey of the site
(Expert Panel, 2002). A thorough description
of soils tests necessary to determine the
optimum product performance has been
prepared by the US EPA ETV Generic
Verification Protocol for Dust Suppression
and Soil Stabilization Products.
5.1.2 Better Understanding of Dust
Characteristics as an Air
Pollutant
To properly evaluate the impacts of dust
suppressants one must understand the char-
acteristics of dust. One key factor is the size
of the particle matter. Airborne particle size
fractions are classified as either Particulate
Matter (PM) 2.5 or PM10, based on their
aerodynamic diameter, when they are regu-
lated under the Clean Air Act. Airborne
fugitive dust entrained from road surfaces
23
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and wind-eroded from construction sites,
agricultural fields and vacant lands span a
physical size range from less than 1 micron
to about 100 microns; this range includes
(and exceeds, on the large end) the PM2.5
and PM10 size fractions. There is a need for
proper characterization of particle size distri-
bution and mineralogy related to variables
such as vehicle tire loading and speeds on
unpaved roads in different regions (Expert
Panel, 2002). As noted earlier, the smaller
PM2.5 particles may be more harmful from a
human health perspective if inhaled.
The soil surface chemistry, moisture content,
and shapes of dust particles can affect the
ability of different suppressant formulations
to adhere to the particles. The particle size,
shape, surface chemistry, and soil moisture
content are seldom used to assist in the
selection of an appropriate suppressant. In
some cases, the soil silt content (given as
percent passing a #200 screen) and mois-
ture content may be obtained prior to dust
suppressant application. Many of the
standard soil characterization tests are time-
consuming and not well suited to the daily
exigencies of field operations. Development
of simple, robust field apparatus and rapid
methods for characterization of relevant soil
properties could assist in the selection of the
right type of suppressant and the appropriate
application rate for a particular region.
5.1.3 Better Understanding of How
Dust Suppressants Change
After Application
The fundamental mechanisms of how the
dust suppressants work, break down, de-
grade, and move in the environment are not
well understood at this time. "Degradation"
includes effects of solar radiation, abiotic
oxidation, biological transformations, dissol-
ution, and physical weathering. In addition,
the soils characteristics will influence how
the suppressants are degraded (Expert
Panel, 2002). Mechanisms of how dust
suppressants work are well established and
based on research and industry devel-
opment. However, it is not known what
happens to the products after they are appli-
ed and weathering occurs. What daughter
24
products are produced as dust suppressants
break down? Are they benign or toxic,
mobile or immobile? Answers to these ques-
tions can only be obtained from long-term
testing of dust suppressants under field
conditions.
5.1.4 Better Definition of Current and
Potential Problems/Uses
Preliminary data was provided in Section 2.3
on the current and potential uses of dust
suppressants; however, this issue should be
further explored. If national regulations/
guidelines are considered for the use of dust
suppressants, then there needs to be a bet-
ter understanding of the scale of current and
potential usage of dust suppressants. An-
swers to the following questions are needed:
1. In what regions of the United States are
dust suppressants currently being appli-
ed?
2. How much dust suppressant is being
applied nationwide?
3. Have there been adverse environmental
impacts in regions where dust suppres-
sants were applied?
4. What is the potential use of dust
suppressants on unpaved roads and
disturbed lands?
5. Do local and state agencies track the use
of dust suppressants?
5.1.5 Source of Dust Suppressants
and Dilution Water
A major concern is the current lack of infor-
mation on the chemical composition of dust
suppressants. Material Safety Data Sheets
(MSDS's) are commonly provided for dust
suppressant products; however, since pro-
prietary information may be involved,
MSDS's do not necessarily provide infor-
mation about all the chemicals present in the
products. Major manufacturers (e.g., Mid-
west Industrial Supply and Pennzoil
Products) will provide results of environ-
mental tests if the customer asks for the
information, or post the information on the
Internet (Expert Panel, 2002). Manu-
facturers' environmental testing data, while
-------
valuable, is currently not standardized. As an
example, several vendors provide reports
containing bioassay data, but it is sometimes
difficult to compare results among different
products because different test species (e.g.
fathead minnows or water fleas) and dif-
ferent test protocols may be used.
Chemical properties, particularly toxic con-
taminants, can vary significantly depending
on the product. Constituents can also vary
from batch to batch (Expert Panel, 2002).
The environmental impacts of dust suppres-
sants cannot be adequately identified until
concentration ranges for major and trace
chemical constituents are known for the
most common products. Most experts in soil
science, ecology, and biology can estimate
potential environmental impacts in their field
of expertise if they know the chemical com-
position of the product and the site-specific
conditions (Expert Panel, 2002). However,
that information is not fully available.
There is also a concern regarding the
sources of the products used in the dust
suppressants. Although some manufacturers
formulate suppressants from virgin materials,
a majority of commercial products are
reformulated by-products or brines from in-
dustries that would otherwise dispose of
these materials as wastes. Several exam-
ples of waste products reformulated as dust
suppressants include lignin sulfonates and
magnesium chloride brines. In effect, un-
paved roads have become disposal system
for these by-products that are reformulated
and used as dust suppressants. The chem-
ical composition of broad categories of by-
products, such as lignin sulfonates, oils, and
brines will depend on the original source of
the by-products and also on the chemical
processes that generated them. For exam-
ple, the waste oils originating from California
crude oils may contain more metals than
waste oils originating from Pennsylvania
crudes (Expert Panel, 2002). Used oils and
solvents may have even higher toxic concen-
trations.
It is also noteworthy that the use of toxic by-
products in dust suppressants is a recycling
process. The recycling of non-hazardous
waste products into dust suppressants
reduces the cost of the dust suppressant and
eliminates the need for disposal in landfills.
Depending on the by-product, recycling and
reuse into dust suppressants may be the
best way to dispose of some non-hazardous
wastes (Expert Panel, 2002). For example,
some mulch-type suppressants are formu-
lated with non-hazardous wood fiber or
paper pulp, and large volume use of mulch-
type suppressants can significantly reduce
the volume of waste pulp that must either be
landfilled or incinerated.
The sources of the water used for dust
suppressants should also be considered in
assessing the potential impacts. The majority
of suppressants require dilution and typically
applicators will use the water that is most
readily available. Tap water, untreated
surface or ground water or reclaimed muni-
cipal or industrial wastewater could all be
used. Reclaimed wastewater may have
higher levels of nutrients and pathogens than
ordinary tap water or some surface or
groundwaters. In some areas, contaminated
groundwater could inadvertently be used for
mixing of the dust suppressants (Expert
Panel, 2002). Minimum quality standards for
water used directly as a dust suppressant or
as a dilution product should be established
to prevent inadvertent contamination of lands
treated with dust suppressants.
5.1.6 Clearinghouse for Dust
Suppressant Information
There is a need for more information about
the chemicals and formulations used in dust
suppressants (Expert Panel, 2002). Regul-
ators, applicators, and the public don't have
easy access to information that would help
them to decide which dust suppressant types
are safe and effective for specific appli-
cations. An easily-accessible information
center, a "clearinghouse", could help appli-
cators, regulators, and the public acquire the
information needed to make good dust con-
trol decisions. The recommended form of
this clearinghouse is as a World Wide Web
site. EPA maintains several web sites that
could serve as models for a dust suppres-
sant clearinghouse. An example is the
25
-------
CHIEF bulletin board that serves the needs
of state and local air quality regulators. The
clearinghouse could be maintained by EPA
or by another public agency or university.
Content categories for this clearinghouse
could include (Expert Panel, 2002):
1. Information on composition of dust sup-
pressants
2. Easy to follow guidelines for selection
and application
3. List of products not to use
4. Occupational and environmental toxicity
information for different types of dust
suppressants
5. Applicable state and local ordinances
regulating dust suppressant application
6. Information about what happens after
application, both in terms of suppressant
performance and environmental impacts
7. Information for the affected public as well
as for regulators/manufacturers/applica-
tors, including:
a. Contact information for federal, local,
and state agencies regulating use of dust
suppressants
b. Contact information for dust suppres-
sant manufacturers
Complete disclosure by dust suppressant
manufacturers, formulators, and vendors
would be needed in order to address all the
items shown above. Some manufacturers,
formulators, and vendors might be reluctant
to release exact formulation information,
since they could consider the information to
be proprietary. The model for disclosure of
pesticide formulations, where only "active"
ingredients are specifically listed, might
prove useful. However, in the case of dust
suppressants the definition of an "active"
ingredient should include both those consti-
tuents that control dust and any other trace
constituent, which when applied to the land
surface at the intended application rate, has
the potential for environmental impact. How-
ever, the lack of complete cooperation from
vendors should not delay the creation of the
clearinghouse.
26
5.17 Risk Assessment and How to
Decide What to Test For
When making the determination on which
dust suppressant should be used, a robust
risk assessment framework is needed along
with the identification of which test should be
performed. In Section 4, a framework was
provided that outlines the considerations that
one might use to make an assessment.
There are several detailed risk assessment
frameworks available to the industry that
could be used as models.
• The American Society of Testing and
Materials (ASTM)'s Risk-Based Corrective
Action (RBCA) is one of the standard
frameworks for assessing the extent of
petroleum contamination and developing
remedial measures for contaminated lands
(ASTM, 1999)
• ASTM also publishes guides and
standards for ecological considerations for
the use of chemical dispersants in oil spill
response that may provide insight into
development of standards for dust
suppressants (ASTM, 2003)
• EPA has also published guidelines for
remediation of hazardous waste sites
(EPA, 2002)
Unfortunately, these frameworks for risk
assessment were developed for cases
where contamination had already occurred.
One proprietary general guideline exists for
evaluating potential environmental impacts
of release of chemicals to the environment
(see Rohm and Haas Consumer and
Industrial Specialties' Risk Assessment Flow
Chart for Safe Product Use, available at
http://www.rohmhaas.com/rhcis/environmen-
tal/safeproduct.html).
There are no relevant guidelines available
for minimizing environmental and human
health risk from intentional application of
dust suppressants to roads construction
sites, agricultural fields, and vacant lands.
Guidelines do exist for:
• Intentional application of fertilizers to crops
and turf, and
-------
• Intentional application of pesticides to
croplands, turf, and residences
However, in both of these cases, the active
ingredients are well known and impacts have
been fairly well studied. The situation with
dust suppressants is much more ambiguous,
as in many cases, data about their chemical
composition and biological impacts are lack-
ing.
It is recommended that tests performed, as
part of a risk assessment for dust suppres-
sants should focus on the constituents in the
dust suppressant concentrate, in runoff, and
Table 5-1: Relevant EPA and Standard test to be considered in assessing impacts of dust
suppressants.
in the soil after application. It is very likely
that no dust suppressants will be free of
every potential harmful chemical; however, it
is important that guidance documents and
initial recommended threshold levels be
developed to reduce risk. Relevant EPA
methods, compiled from both Expert Panel
recommendations and from the literature
review, are summarized in Table 5-1. These
tests could be applied to the raw product, the
collected runoff, and/or the soils.
Analytical Method
EPA/ASTM Number
Organic
Inorganics/Metals
Toxicity
Biodegradability
Volatile organic compounds
Semi-volatile organic compounds
Pesticides and herbicides
Chlorinated hydrocarbons
Petroleum hydrocarbons
PAHs
Inductively Coupled Plasma-Atomic
Emission Spectrometry
Terrestrial bird toxicity
Insect toxicity
Vegetation toxicity
Algal Toxicity
Acute to fishes and microinvertebrates
Marine and Estuary organisms
Chronic to fishes and microinvertebrates
Dredge material chemical and biological
evaluation
Bioconcentration
Soluble Chemical Oxygen Demand
Biochemical Oxygen Demand
8260B
8270D
8270D
8121
8440
Tentatively identified compounds (TIC)
6010B
850.2200
850.3020
850.4000
850.4400
ASTME-1192-88
EPA/600/4-85-013 and EPA 600/4-87-028
EPA/600/4-89-001
U.S. Corps. Engr. Rep-D90
ASTME-1022-84
410.4
405.1
5.18 Example of a Standardized
Assessment Methodology
As part of an initial risk assessment for this
report, a proposed standardized methodol-
ogy for estimating soil mass fractions of dust
suppressant constituents is shown below in
Tables 5-2 and 5-3. The worksheets use
known information about a dust suppressant
constituent concentration, the application
rate, the soil penetration, and soil density to
estimate a dust suppressant constituent
concentration in soil. Table 5-2 is provided
as a blank worksheet for vendors, applica-
tors, regulators, and investigators to use in
their risk assessments. Table 5-3 shows an
example calculation for a constituent present
at a 50 mg/L in a dust suppressant concen-
trate.
27
-------
Table 5-2: Blank Worksheet A - Estimation of soil mass fraction from suppressant constituent
concentration.
Blank Worksheet A: Calculation of constituent concentration in soil
Fill in shaded blanks with your data and complete calculations in other rows per Calculation
Instructions
User-
supplied Row # Data Entry or Calculation Instruction Value Units
1 Concentrate constituent concentration
2 Dilution: volume water/volume concentrate
3 Mixed constituent concentration = concentrate concentration / (1
+ dilution)
4 Liquid mixture application rate per pass
5 Number of passes
6 Total liquid mixture application rate/yd2 = rate/pass x number
passes
7 Land area conversion
8 Converted total liquid mixture application rate per m2 = row 6 x
row 7
9 Mixture volume conversion
10 Total Liquid mixture application rate (metric) = row 8 x row 9
11 Runoff fraction (fraction leaving site before infiltration into soil)
12 Retained liquid application rate = Total rate x (1 - runoff fraction)
13 Mixture liquid depth applied to soil = (row 12 x (1 meter3/1000
liter) x 100cm/meterx 1 inch/2.54 cm
14 Constituent application rate as mass/area soil = mixed constituent
concentration (row 3) x liquid mixture rate (row 12)
15 Diluted mixture penetration (inches)
16 Length conversion
17 Diluted mixture penetration (centimeters) = row 15 x row 16
18 Diluted mixture penetration (meters) = row 17/100
19 Constituent soil concentration as mass constituent/volume soil =
constituent application rate (row 14) / diluted mixture
penetration (row 18)
20 Soil bulk density
21 Initial constituent mass fraction in soil = constituent soil
concentration (row 19) / soil bulk density (row 20)
mg/L
mg/L
gallon/yd2
gallon/yd2
1.20 yd2/m2
gallon/m2
3.78 liter/gallon
Iiter/m2
inches
mg/m2
inches
2.54 cm/inch
centimeters
meters
mg/m3
kg/m3
mg/kg = ppm
28
-------
Table 5-3: Example calculation using Worksheet A. Soil mass fraction resulting from
application of dust suppressant with constituent concentration of 50 mg/L.
Assumes 1,600 kg/m3 soil bulk density, 0.45 inch (1.14 cm) suppressant
penetration into soil, 2 suppressant applications at 0.50 gallon/yd2, no runoff of
liquid suppressant, and mixing of 1 volume of suppressant concentrate with 1
volume of water.
Worksheet A Example 1: Estimation of constituent soil mass fraction based on
constituent concentration in suppressant as supplied (concentrate)
User-
supplied
*
*
*
*
*
*
*
Row#
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
Data Entry or Calculation Instruction
Concentrate constituent concentration
Dilution: volume water/volume concentrate
Mixed constituent concentration = concentrate
concentration / (1 + dilution)
Liquid mixture application rate per pass
Number of passes
Total liquid mixture application rate/yd2 = rate/pass x
number passes
Land area conversion
Converted total liquid mixture application rate per m2 =
row 6 x row 7
Mixture volume conversion
Total Liquid mixture application rate (metric) = row 8 x row
9
Runoff fraction (fraction leaving site before infiltration into
soil)
Retained liquid application rate = Total rate x (1 - runoff
fraction)
Mixture liquid depth applied to soil = (row 12 x (1
meter3/1000 liter) x 100cm/meterx 1 inch/2.54 cm
Constituent application rate as mass/area soil = mixed
constituent concentration (row 3) x liquid mixture rate
(row 12)
Diluted mixture penetration (inches)
Length conversion
Diluted mixture penetration (centimeters) = row 15 x row
16
Diluted mixture penetration (meters) = row 17/100
Constituent soil concentration as mass constituent/volume
soil = constituent application rate (row 14) / diluted
mixture penetration (row 18)
Soil bulk density
Initial constituent mass fraction in soil = constituent soil
concentration (row 1 9) / soil bulk density (row 20)
Value
50
1
25
0.50
2
1.00
1.20
1.20
3.78
4.53
0.00
4.53
0.18
113
0.45
2.54
1.14
0.0114
9,900
1,600
6.19
Units
mg/L
mg/L
gallon/yd2
gallon/yd2
yd2/m2
gallon/m2
liter/gallon
Iiter/m2
Iiter/m2
inches
mg/m2
inches
cm/inch
centimeters
meters
mg/m3
kg/m3
mg/kg = ppm
Environmental regulations establish action
levels for contaminants or contaminant clas-
ses in soils. Remediation is usually required
if values above these levels are recorded for
a contaminated site. Tables 5-4, 5-5, and 5-6
show a proposed calculation methodology
for using an action level in soil to estimate
the maximum allowable constituent concen-
29
-------
tration in a formulated dust suppressant
concentrate. Table 5-4 is provided as a blank
worksheet for interested parties to use in risk
assessments involving suppressants. Table
5-5 shows a sample calculation for a RCRA-
based action level of 100 ppm for total
petroleum hydrocarbons (TPH). Table 5-6
shows a sample calculation for a CERCLA-
based action level of 1 ppb for tetrachloro-
dibenzodioxin (TCDD). The final result
computed at the bottom of Tables 5-5 and 5-
6 should not be considered as a fixed "not to
exceed" value for TPH or TCDD, as the
numerical result depends on dust suppres-
sant liquid application rate, penetration depth
into the soil, fraction suppressant retained on
the target surface, suppressant dilution, and
soil bulk density. However, the results are
instructive, and the accompanying blank
worksheet (Table 5-4) could be used with
site-specific data to compute maximum
allowable constituent (or contaminant) con-
centrations for other combinations of site
conditions, suppressant dilutions, and appli-
cation rates.
Table 5-4: Blank Worksheet B - Estimation of maximum allowable dust suppressant constituent
concentration from risk-based limit in soil.
Blank Worksheet B: Calculation of maximum suppressant contaminant
concentration based on maximum allowed soil contaminant mass fraction
Fill in shaded blanks with your data and complete calculations in other rows per Calculation
Instructions
User-
supplied
*
*
*
*
*
*
Row#
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
Data Entry or Calculation Instruction
Initial constituent mass fraction in soil
Soil bulk density
Constituent soil concentration as mass constituent/volume soil =
constituent soil mass fraction (row 1 ) x soil bulk density (row 2)
Diluted mixture penetration (inches)
Length conversion
Diluted mixture penetration (centimeters) = row 4 * row 5
Diluted mixture penetration (meters) = row 6/100
Constituent application rate as mass/area soil = constituent soil
concentration (row 3) x diluted mixture penetration (row 7)
Liquid mixture application rate per pass
Number of passes
Total liquid mixture application rate/yd2 = row 9 x row 10
Land area conversion
Converted total liquid mixture application rate per m2 = row 1 1 x
row 12
Mixture volume conversion
Total liquid mixture application rate (metric) = row 13 x row 14
Runoff fraction (fraction leaving site before infiltration into soil)
Net liquid application rate = row 15 x (1 - row 16) as volume/ area
Value Units
mg/kg = ppm
kg/m3
mg/m3
inches
2.54 cm/inch
centimeters
meters
mg/m2
gallon/yd2
gallon/yd2
1 .20 yd2/m2
gallon/m2
3.78 liter/gallon
Iiter/m2
soil
18 Mixture liquid depth applied to soil = (row 17 x (1 meter3/1000
liter) x 100cm/meterx 1 inch/2.54 cm
19 Max allowed concentration in diluted mixture = row 8 / row 17
20 Intended dilution: volume water / volume concentrate
21 Maximum allowed concentration in suppressant concentrate as
supplied = row 19 x (1 + row 20)
Iiter/m2
inches
mg/L
mg/L
30
-------
Table 5-5: Example calculation of maximum allowable suppressant concentration based on
RCRA 100 ppm action level for Total Petroleum Hydrocarbons (TPH) in soil as
determined using EPA Method 8015. Assumes 1,600 kg/m3 soil bulk density, 0.45
inch (1.14 cm) suppressant penetration into soil, 2 suppressant applications at
0.50 gallon/yd2, no runoff of liquid suppressant, and mixing of 1 volume of
suppressant concentrate with 1 volume of water.
Worksheet B Example #2: Calculation of maximum allowable suppressant
contaminant concentration based on maximum allowed soil contaminant mass
fraction. RCRA soil limit of 100 ppm maximum allowable TPH in soil from EPA
Method 8015
User-
supplied Row # Data Entry or Calculation Instruction Value Units
0.45
mg/m3
inches
2.54 cm/inch
1.14 centimeters
1829 mg/m2
0.50 gallon/yd2
1.00 gallon/yd2
1 Initial constituent mass fraction in soil 100.00 mg/kg = ppm
2 Soil bulk density 1,600 kg/m3
3 Constituent soil concentration as mass
constituent/volume soil = constituent soil mass fraction
(row 1)x soil bulk density (row 2) 160,000
4 Diluted mixture penetration (inches)
5 Length conversion
6 Diluted mixture penetration (centimeters) = row 4 * row 5
7 Diluted mixture penetration (meters) = row 6 /100 0.0114 meters
8 Constituent application rate as mass/area soil =
constituent soil concentration (row 3) x diluted mixture
penetration (row 7)
9 Liquid mixture application rate per pass
10 Number of passes
11 Total liquid mixture application rate/yd2 = row 9 x row 10
12 Land area conversion
13 Converted total liquid mixture application rate per m2 =
row 11 x row 12
14 Mixture volume conversion
15 Total liquid mixture application rate (metric) = row 13 x
row 14
16 Runoff fraction (fraction leaving site before infiltration into
soil) 0.00
17 Net liquid application rate = row 15 x (1 - row 16) as
volume/ area soil
18 Mixture liquid depth applied to soil = (row 17 x (1
meter3/1000 liter) x 100cm/meterx 1 inch/2.54 cm 0.18 inches
19 Max allowed concentration in diluted mixture = row 8 /
row 17 404 mg/L
20 Intended dilution: volume water/volume concentrate 1
21 Maximum allowed concentration in suppressant
concentrate as supplied = row 19 x (1 + row 20) 808 mg/L
1.20 yd2/m2
1.20 gallon/m2
3.78 liter/gallon
4.53 Iiter/m2
4.53 Iiter/m2
31
-------
Table 5-6: Example calculation of maximum allowable suppressant concentration based on
CERCLA 1 ppb action level for TCDD. Assumes 1,600 kg/m3 soil bulk density, 0.45
inch (1.14 cm) suppressant penetration into soil, 2 suppressant applications at
0.50 gallon/yd2, no runoff of liquid suppressant, and application of undiluted
suppressant to land surface.
Worksheet B Example #3: Calculation of maximum allowable suppressant
contaminant concentration based on maximum allowed soil contaminant mass
fraction. CERCLA limit of 1 ppm maximum allowable dioxin in soil.
User-
supplied Row # Data Entry or Calculation Instruction Value Units
1 Initial constituent mass fraction in soil
2 Soil bulk density
3 Constituent soil concentration as mass
constituent/volume soil = constituent soil mass fraction
(row 1)x soil bulk density (row 2)
4 Diluted mixture penetration (inches)
5 Length conversion
6 Diluted mixture penetration (centimeters) = row 4 * row 5
7 Diluted mixture penetration (meters) = row 6/100
8 Constituent application rate as mass/area soil =
constituent soil concentration (row 3) x diluted mixture
penetration (row 7)
9 Liquid mixture application rate per pass
10 Number of passes
11 Total liquid mixture application rate/yd2 = row 9 x row 10
12 Land area conversion
13 Converted total liquid mixture application rate per m2 =
row 11 x row 12
14 Mixture volume conversion
15 Total liquid mixture application rate (metric) = row 13 x
row 14
16 Runoff fraction (fraction leaving site before infiltration into
soil)
17 Net liquid application rate = row 15 x (1 - row 16) as
volume/ area soil
18 Mixture liquid depth applied to soil = (row 17 x (1
meter3/1000 liter) x 100cm/meterx 1 inch/2.54 cm
19 Max allowed concentration in diluted mixture = row 8 /
row 17
20 Intended dilution: volume water / volume concentrate
21 Maximum allowed concentration in suppressant
concentrate as supplied = row 19 x (1 + row 20)
22 Maximum allowed concentration (ppb) = row 21 x 1000
0.001
1,600
mg/kg = ppm
kg/m3
1.60
0.45
mg/m3
inches
2.54 cm/inch
1.14 centimeters
0.0114 meters
1.83E-02 mg/m2
0.50 gallon/yd2
1.00 gallon/yd2
1.20 yd2/m2
1.20 gallon/m2
3.78 liter/gallon
4.53 Iiter/m2
0.00
4.53
0.18
Iiter/m2
inches
4.04E-03 mg/L
0
4.04E-03 mg/L
4.04 ,wg/L (ppb)
32
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5.2 Regulatory Issues
5.2.1 Gaps in Existing Regulations
At present, few specific regulations for dust
suppressants exist. Decision-makers cur-
rently rely on emerging voluntary certification
programs (Section 2.7), and a limited num-
ber of state and local guidelines to screen
the different types of dust suppressants for a
variety of application scenarios. Current
state, local, and national guidelines are not
uniform. While current voluntary certification
programs have merit, they need to be ex-
panded to incorporate a majority of dust
suppressants in commerce. Dust sup-
pressants should be evaluated not only for
their effectiveness in suppressing dust but
also for their potential toxicological and envi-
ronmental effects.
Regulations to support existing environ-
mental laws (e.g., RCRA, CERCLA/SARA
guidelines, as were used to clean up the
Superfund site at Times Beach) may apply at
some point after a dust suppressant has
been applied. However, existing regulations
are not applicable to the production and
application of dust suppressant. RCRA rules
were not written with dust suppressants in
mind. Although they allow for waste ex-
changes and other waste reprocessing
steps, their principal intent is to regulate the
treatment, storage, and disposal of municipal
and hazardous wastes. CERCLA/SARA
rules are intended to finance and guide the
clean up of contaminated sites. In contrast,
the major regulatory need for dust suppres-
sants is to develop guidelines that will
prevent the creation of hazardous waste
sites from the inappropriate use of dust sup-
pressants. The Toxic Substance Control Act
(TOSCA) is intended to regulate hazardous
substances prior to them becoming hazar-
dous waste.
5.2.2 Filling the Regulatory Gaps -
What's Available in Existing
Regulations?
Is the current regulatory environment for dust
suppressants adequate to ensure that the
risks have been considered and their use is
acceptable? It was the opinion of the Expert
Panel that it is not adequate. The Expert
Panel generally agreed that more research is
needed to answer questions about the
potential environmental impacts of dust sup-
pressants, but also agreed that development
of regulations should not wait for all the
science to be completed (Expert Panel,
2002).
A complication in developing new regulations
is that the composition of dust suppressants
may not be adequately known and com-
ponents or byproducts of the suppressants
may have potentially harmful environmental
impacts. Although existing regulations are
not intended to regulate the flows of Indus-
trial wastes into the formulation of dust
suppressants and thence to the environ-
ment, the existing regulations do contain
limits on contaminant concentrations in soil
that could be used as a starting point for
regulations and guidelines for dust suppres-
sants. For instance, a similar approach may
be considered as that for the land application
sludges. The regulations currently in place
for the land application of sewage sludge
and wastewater on agricultural fields limits
the loading rate of metals based on land use.
The Federal Insecticide, Fungicide and Ro-
denticide Act (FIFRA), Resource Conserva-
tion Recovery Act (RCRA), Comprehensive
Environmental Response Compensation and
Liability Act (CERCLA), Superfund Amend-
ments and Reauthorization Act (SARA),
Ecological Soil Screening Level (Eco-SSL)
guidance with supporting regulations and
guidelines collectively restrict the environ-
mental concentrations of hundreds or
thousands of chemicals. Many of these
programs are good models for identifying
potential problems; however, they need to be
followed up with site-specific studies. It is
recommended that:
1. State and federal regulatory databases
for these compounds be reviewed, and
the results organized to produce a data-
base of compounds whose use would be
restricted or prohibited in dust suppres-
sants (Expert Panel, 2002).
2. Contaminant concentrations of modeled
dust suppressant constituents and by-
33
-------
products in water should be compared
against action levels used in the Clean
Water Act and Safe Drinking Water Act
since dust suppressants could eventually
be transported into surface and ground
waters. Any dust suppressant compound
that could reasonably be expected to
exceed existing regulatory-based action
levels or thresholds would need to be
examined in detail to determine whether
additional regulatory controls were need-
ed to prevent unreasonable risks to
human health and the environment.
Regarding regulating dust suppressant appli-
cation practices, some guidance might be
found in U.S. Department of Agriculture
(USDA) regulations that control the appli-
cation of chemical fertilizers and also in
regulations that control the application of
pesticides under FIFRA. As noted earlier,
there are also state programs being devel-
oped. These state programs may be the
most appropriate since they can better
address regional issues related to dust
suppressant use than a "one size fits all"
federal program.
5.2.3 What's Next for Regulations?
New regulations must be developed to deal
with the variety of compounds, application
scenarios, and potential receptors that are
involved with the growing use of dust
suppressants. A variety of potential regula-
tory approaches specifically focused on dust
suppressants exist, ranging from extending
the current patchwork approach of local and
state regulations to development of a com-
prehensive national program enforcement of
which would likely be delegated to the
states. An alternative to a comprehensive
national program might be a basic national
program that specifically makes dust sup-
pressant products subject to other existing
regulatory thresholds for toxicity and requires
some type of testing and/or certification to
validate that these limits are met. States
could be encouraged to develop a more
comprehensive regulatory program for dust
suppressant products and their use based
on regional topography, hydrology, soil
types, ecosystems, and material availability.
The range of regulatory topics could include:
1. Limiting the types and number of sup-
pressants allowed, and
2. Regulating the locations and application
practices of specific types of dust sup-
pressants (Expert Panel, 2002).
3. Regulating the exposure of workers to
dust suppressants.
An effort to limit and specify which dust
suppressants could be applied for dust
control would be challenging because of the
broad variety of products used as dust
suppressants, their complex chemistry, and
the increasing number of products and
industrial by-products regularly introduced to
the market. However, limiting the types of
dust suppressants allowed for use would
make enforcement of environmental regula-
tions much simpler (Expert Panel, 2002). A
regulatory-derived list of acceptable dust
suppressants would bar access of several
vendors to the market and would not be well
received. In addition, there was concern that
such an approach would discourage the
development of more effective and more
environmentally benign suppressants (Ex-
pert Panel, 2002).
Regulating dust suppressant application lo-
cations and application practices, rather than
the types and number of suppressants,
would allow for the varying sensitivities of
different ecosystems to different dust sup-
pressant formulations (See framework
proposed in Section 4). For example, a dust
suppressant with relatively insignificant im-
pacts in one area (an arid flatland system
with no perennial surface water flows and
deep groundwater) might have significant
impacts in another area (a humid moun-
tainous system with significant perennial
surface water flows and shallow ground-
water). In the flat arid land case, the
suppressant is likely to stay put in the soil for
a long time, with minimal aquatic impacts. In
the mountainous humid case, significant
portions of the suppressant may rapidly
reach surface and ground waters and could
have significant aquatic impact.
34
-------
Also, application rates and practices are
important since dust suppressants with
seemingly benign characteristics when
applied at a rate of 1,000 mg/kg soil might
produce significant impacts on the environ-
ment or human health if it is applied at 10
times the rate (10,000 mg/kg soil) or if the
surrounding environment and individuals are
particularly sensitive. High soil mass frac-
tions could inadvertently develop if there is
significant overspray onto previously treated
surfaces during application.
The effectiveness of a suppressant should
be considered in any evaluation of the
application and potential impacts of dust
suppressants. A short-lived, easily wea-
thered dust suppressant requiring frequent
re-application could have more significant
environmental impacts than a long-lived,
weather-resistant suppressant, when both
contain the same concentration of a mobile
trace contaminant. Frequent reapplication of
the easily weathered suppressant would
produce higher soil and aquatic concen-
trations of the trace contaminant than
infrequent applications of the weather-
resistant suppressant. If effectiveness is not
considered, decision-makers might choose
the "most environmentally friendly suppres-
sant" rather than select a more effective dust
suppressant that is just as environmentally
benign for one application and more benign
over the long term (Expert Panel, 2002).
The evaluation and/or certification of specific
dust suppressants should not be a one-time
process, but should instead be subject to
periodic renewal. Waste products that are
recycled into dust suppressants can vary in
composition through time, and this variability
must be considered in any comparison of a
dust suppressant batch to a fixed set of
environmental criteria. Out-of-specification
products should not be considered bad, but
they should be scrutinized (Expert Panel,
2002).
If additional regulations are developed for
dust suppressants, certain criteria should be
met (Expert Panel, 2002):
1. Regulations should be practical.
2. A regulatory program to track dust sup-
pressants should not be overwhelming in
amount of required information.
3. Regulatory guidelines should benefit
governments who rely on dust control in
preparing State Implementation Plans
(SI Ps) for PM10.
4. Training needs to accompany the regu-
lations.
5. A model, decision-tree, or expert system
is needed to help decide: what to use,
how much to use, for different dust
applications and environmental situations
(e.g., Figure 4-1).
6. Sufficient EPA-approved and standard
analytical testing methods to evaluate
suppressant chemical characteristics ex-
ist (Table 5-1); however, as part of the
regulatory process, the types of tests to
be used should be specified. Tests
should be carefully selected to provide
the information that is necessary to
assess potential exposures to critical
receptors through those media that are
of concern in the area where the
suppressant will be applied. The EPA's
Data Quality Objective process provides
the framework for assessing the type of
information that is critically needed to
assess the data that are required to
evaluate potential exposures.
7. In addition to the tests to determine the
potential environmental impacts, the
regulations should contain Application
Practice Guidelines (APGs). Application
Practice Guidelines should include infor-
mation about the types of areas where
specific suppressants can be applied
(predominant biota and soil types), wind
velocity limitations at the time of appli-
cation, specific limitations on application
in proximity to water bodies, runoff chan-
nels, and residential areas, regulations
on the types of containers that may be
used to transport suppressants [some of
this may already be in place in RCRA-
inspired rules promulgated by EPA and
the U.S. Department of Transportation
(DOT)].
35
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Among the questions that applicators and
regulators would need answered in order to
establish a list of prohibited categories of
dust suppressants are (Expert Panel, 2002):
1. What formulated and in-soil concentra-
tions should not be exceeded for specific
compounds?
2. If some formulations are already known
to contain harmful contaminants (such as
TCDD), one could start by prohibiting or
restricting suppressant formulations
containing those harmful compounds.
Additional detailed discussion of this
approach, using restrictions found in ex-
isting environmental regulations, can be
found in Section 5.2.2 above.
3. Can obviously ineffective chemical
formulations, passed off as dust sup-
pressants, be prohibited? For example,
could a 5% sodium hydroxide NAOH
solution in water, be applied to soil and
be labeled as a dust suppressant? What
can be done to prevent this? Does any
existing legislation cover this situation?
4. Should there be a required consistency
of dust suppressant composition? A
public right-to-know may lead to a re-
quirement for batch-to-batch consistency
of composition.
5. How does one develop a reliable testing
process to determine if industrial wastes
or byproducts, not originally formulated
for use as dust suppressants, can be
effective suppressants and safely
applied? Currently, manufacturers do "in-
house" or contracted testing of perfor-
mance and toxicity.
Additional Recommendations by the Expert
Panel included the following:
1. Regulatory exclusions for certain classes
of compounds should be re-examined.
For example, the RCRA petroleum ex-
clusion allows reintroduction of oily
wastes into the marketplace and some of
these could cycle back into the environ-
ment in dust suppressant formulations
(Expert Panel, 2002).
2. Information contained in the MSDS is not
sufficient to evaluate the potential
36
environmental impacts of suppressants.
Manufacturers should transparently and
completely report the chemical compo-
sitions of their dust suppressant
formulations. (Expert Panel, 2002). Re-
gulations requiring more information on
an MSDS should be considered.
3. Finally, regulations should prevent entry
of "rogue" dust suppressants into the
marketplace. A reputable dust sup-
pressant should have a consistent
formulation and independently verifiable
test results demonstrating product effect-
iveness and low environmental impacts,
and will be made by manufacturers with
consistent track records in the dust
suppressant business. Rogue products
will typically come without test results
from one-time manufacturers that are
looking to get rid of a waste product.
Certification and regulation are the best
ways to prevent entry of rogue products
into the marketplace and the environ-
ment. Reputable manufacturers would
welcome a certification program (Expert
Panel, 2002).
5.2.4 Response to Regulatory
Uncertainty - Risk Driven
Regulatory Response
While current certification and testing proto-
cols focus on evaluating the effectiveness of
a dust suppressant, more needs to be done
to assess potential adverse impacts from
dust suppressants and to estimate risks.
Regulatory efforts should be focused first on
those compounds and applications that pose
the greatest risks to human health and the
environment.
A risk assessment model combined with a
transport and fate model is required to eval-
uate potential exposures and adverse risks.
For the decision-maker or regulator, a
decision-making model or expert system to
assist in making site-specific decisions would
be of value. Without these models or tools, a
decision-maker could either make decisions
or develop regulations that are very conser-
vative in the use of dust suppressants.
Excessively conservative regulation may not
maximize the benefits to be gained from
-------
using dust suppressant products and could
be challenged in the courts. Conversely, the
decision-maker could allow widespread use
of dust suppressants with the potential for
unintended consequences. Sufficient infor-
mation already exists to make a start at
preventing either of the above two scenarios.
After 25 years of environmental remediation
efforts, risk-based concentration limits have
been established for a number of com-
pounds and compound classes. Additionally,
risk assessment frameworks, such as
ATSM's RBCA guidelines, may prove
instructive.
An example of this approach would be a risk-
benefit analysis to determine how much
PM10, and PM2.5 dust is suppressed with
each suppressant. Information that would be
needed include the potential environmental
impacts, the costs associated with the using
or not using dust suppressants, the potential
environmental benefits associated using dust
suppressants. There also needs to be a
consideration that many regions are rapidly
moving toward a PM2.5 standard and away
from a PM10 standard. This is due to the
emerging cancer issues and cardiopul-
monary disease. However, tighter standards
will raise the quality of the environment and
the cost associated with that environment.
5.3 Final Recommendations
The additional environmental regulations that
have been developed since the 1970's when
the Times Beach situation occurred have
reduced the chances that dioxin-contamin-
ated waste oil be used as dust suppressants.
However, dust suppressants are not speci-
fically regulated under any major federal
legislation and there is still significant poten-
tial for other environmentally hazardous
materials to be used.
1. In the SHORT TERM, the chances that
hazardous materials are used can be
reduced by:
a. Establishing an interagency working
group that evaluates the cross media
and cross jurisdictional issues associ-
ated with the use of dust suppres-
sants.
b. Closing regulatory loopholes that
allow entry of unlimited industrial
wastes into the environment when
they are classified as dust suppres-
sants. All industrial waste must be
sampled prior to use.
c. Requiring complete disclosure of all
dust suppressant constituents
through independent standardized
testing of dust suppressant for-
mulations. Testing should recur
periodically and whenever the formu-
lation changes manufacturers using
waste products must test each batch.
d. Developing and employ a risk-based
expert system (or decision tree) to
prohibit or severely restrict the
concentrations of environmental con-
taminants known to be persistent and
harmful.
e. Developing conservative guidelines
(APGs) for application of different
types of dust suppressants in major
broad ecosystem categories.
f. Requiring standardized biological
toxicity testing for major dust sup-
pressant types.
g. Requiring training for all personnel
who use and regulate dust suppres-
sants.
2. The risks associated with dust suppres-
sant use can be reduced in the LONG
TERM by:
a. Encouraging the development of dust
suppressant formulations that are
long-lived and environmentally be-
nign.
b. Continuing to develop scientific in-
formation about the environmental
impacts of dust suppressants.
c. Using information developed in 2a
and 2b to update risk-based
regulations and application and
management practices.
37
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38
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Cowherd Jr., C., Elmore, W.L., Durkee, K.R., 1989. Potential Regulatory Approaches for the
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Demers, C.L., Sage Jr., R.W., 1990. Effects of Road De-icing Salt on Chloride Levels in Four
Adirondack Streams, Water, Air, and Soil Pollution, 49:369-373.
Ettinger, W.S., 1987. Impacts of a Chemical Dust Suppressant/Soil Stabilizer on the Physical
and Biological Characteristics of a Stream, Journal of Soil and Water Conservation, 42(2):
111-114.
Foley, G., Cropley, S., and Giummara, G., 1996. Road Dust Control Techniques - Evaluation of
Chemical Dust Suppressant's Performance, ARRB Transport Research Ltd., Special Report
54, Victoria, Australia.
Gebhart, D.L., Denight, M.L., Grau, R.H., 1999. Dust Control Guidance and Technology
Selection Key. U.S. Army Environmental Center- U.S. Army Corps of Engineering, AEC
Report No. SFIM-AEC-EQ-CR-99002.
Gilles, J.A., Watson, J.G., Rogers, C.F., Chow, H.C., 1997. PM10 Emissions and Dust
Suppressants Efficiencies on an Unpaved Road, Merced County, CA. In: Proceedings of the
Air and Waste Management Association's 90th Annual Meeting and Exhibition, June 8-13,
Toronto, Ontario, Canada.
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Golden, B.J., 1991. Impact of Magnesium Chloride Dust Control Product on the Environment,
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Hanes, R.E., Zelanzny, L.W., and Blaser, R.E., 1970. Effects ofDeicing Salts on Water Quality
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Hanes, R.E., Zelanzny, L.W., Verghese, K.G., Bosshart, R.P., Carson Jr., E.W., Wolf, D.D.,
1976. Effects ofDeicing Salts on Plant Biota and Soil. National Cooperative Highway
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James, D., Pulgarin, J., Gingras, T., Edwards, S., Venglass, G., Becker, J., Licon, A., Swallow,
C., Gambatese, J., Luke, B., 1999. Field Testing of Dust Suppressants Using a Portable
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Kestner, M., 1989. Using Dust Suppressants to Control Dust Emissions - Part 1, Powder and
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Lewis, R.J., 1993, Hawley's Condensed Chemical Dictionary, Twelfth edition.
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An Environmental Evaluation of Dust Suppressants: Calcium Chloride and Ligninsulfonate.
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with Dust Suppressants. Journal of Hydrologic Engineering, September 2003.
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Massachusetts, The American Society of Mechanical Engineers, Volume 8.
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42
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Appendix A
Literature Review
43
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44
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LI n i v e r s i t y of n e v a d a , las v e g, a
Literature Review
Dust Suppression and Its Environmental Impacts
Prepared for the Expert Panel on
Potential Environmental Impacts of Dust Suppressants:
"Avoiding Another Times Beach"
Principal Investigators:
Dr. Jacimaria Batista
Dr. Thomas Piechota
Dr. David James
Dr. Krystna Stave
University of Nevada, Las Vegas
4505 Maryland Parkway, Box 454015
Las Vegas, NV 89154-4015
Graduate Student:
Daniela Loreto
May 30 and 31, 2002
Las Vegas, Nevada
45
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46
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Dust Suppression and Its Environmental Impacts
In recent years, studies on fugitive dust control have significantly increased in the United States. This
literature review summarizes the current status of the use of dust suppressants with respect to types of
materials used, application rates, effectiveness, environmental impacts, and costs. In 1991, 75-80% of all
dust suppressants used were chlorides and salt brine products, 5-10% were ligninsulfonates, and 10-15%
were petroleum-based products (Travnik, 1991). There has been much research on the effectiveness of
dust suppressants; however, little information is available on the potential environmental impacts and
costs of these compounds. The categories of dust suppressants most frequently used to control fugitive
dust are listed in Table 1.
Table 1 - Most commonly used dust suppressants (modified from Bolander, 1999a)
Suppressant Type
Water
Salts and brines
Petroleum-based organics
Non-petroleum based organics
Synthetic polymers
Electrochemical products
Clay additives
Mulch and fiber mixtures
Products
Fresh, reclaimed, and seawater
Calcium chloride, and magnesium chloride
Asphalt emulsion, cutback solvents, dust oils, modified asphalt
emulsions
Vegetable oil, molasses, animal fats, ligninsulfonate, and tall oil
emulsions
Polyvinyl acetate, vinyl acrylic
Enzymes, ionic products (e.g. ammonium chloride), sulfonated oils
Bentonite, montmorillonite
Paper mulch with gypsum binder, wood fiber mulch mixed with
brome seed
Water
Surface watering is an immediate, inexpensive short-term solution to control dust (Gebhart et al.,
1999). Water suppresses dust by agglomerating surface particles. However, the effectiveness depends
upon temperature and humidity. Water can be effective for a period as short as half an hour and as long
as twelve hours (Foley et al., 1996, Schwendeman, 1981). Thompson (1990) found water was 85%
effective in controlling dust in coal mines. Water effectiveness in controlling dust in roads and dirty beds
has been estimated to be 40% (Travnik, 1991, Foley et a/., 1996). Water has little residual effect. Once
applied it evaporates quickly, especially in hot, dry climates (Kestner, 1989a). Cowherd et al. (1989)
reports that dust suppression efficiency decays from 100% to 0% in a very short time. Water is most
efficient on sites where vehicular traffic is limited. Seawater is more effective than fresh water as a
suppressant owing to the presence of salts.
Salts and Brines
The most widely used compounds in this category of suppressants are magnesium chloride (MgCI2),
and calcium chloride (CaCI2) (Sanders and Addo, 1993). Salts suppress dust by attracting moisture from
the air, which keeps the surface humid (Foley et al., 1996). Sodium chloride is not a very useful
suppressant in arid regions because it only absorbs water when the humidity exceeds 75%.
Calcium chloride is a by-product of the ammonia-soda (Solvay) process and a joint product from
natural salt brines. The ability of calcium chloride to absorb water from the air is a function of the relative
humidity and ambient temperature. Calcium chloride is more effective in places that have high humidity
and low temperatures (Foley et al., 1996). Bolander (1999a) reports that calcium chloride at a
temperature of 25°C, for example, starts to absorb water at 29% relative humidity, and at 38°C it starts to
absorb water at 20% relative humidity.
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Magnesium chloride is created either from seawater evaporation or from industrial by-products
prepared from magnesium ammonium chloride hexahydrate in the presence of HCI. It is a more effective
salt than calcium chloride because it increases the surface tension and has a harder surface when it is
dry (Foley et al., 1996). It has a low freezing point (-34°C) and serves as a de-icing agent. Magnesium
chloride needs a minimum of 32% humidity to absorb water from the air independent of the temperature.
It remains more hygroscopic at higher temperature than calcium chloride and is therefore more suitable to
dry climates (Langdon and Williamson, 1983). Compared to water, salts are more effective in controlling
dust if sufficient moisture is available. The effectiveness of salts to control dust significantly decreases
with time. The dust abatement properties of magnesium chloride have been found to last about 12 weeks
(Monlux, 1993). Another problem with salts is that they migrate readily in the environment. DeCastro et al.
(1996) modeled the movement of road stabilization additives of road surface to determine how long the
additives remained effective. They found that calcium and magnesium chlorides are easily carried from
the soil. Table 2 summarizes several studies on the effectiveness of salts in minimizing fugitive dust.
Table 2 - Effectiveness of salts as dust suppressants
Suppressant Type
Calcium chloride
Magnesium chloride
Magnesium chloride sprayed
during street sweeping
Calcium chloride, magnesium
chloride, and ligninsulfonate
Petro-tac, Coherex, Soil-Sement
Generic Petroleum Resin, and
Calcium chloride
Effectiveness
55% aggregate retention as compared
to control.
Compared to control, retained 77% of
the aggregates.
26% MgCI2 solution reduced dust by
92%. 60% MgCI2 solution reduced dust
by 58%.
Reduced fugitive dust by 50-70%
Increased aggregate retention by 42-
61%. Under low humidity and high
temperatures ligninsulfonate was more
effective than salts.
95% effective after application to
control dust particles < 15, 10, and 2.5
//m. Over a 30-day period,
effectiveness decreased as much as
50% and as little as 10%.
Reference
Sanders and Addo, 1993
Sanders and Addo, 1993
Satterfield and Ono,
1996
Sanders et al., 1997
Muleski and Cowherd,
1987
Organic Non-Petroleum Products
Organic non-petroleum products include ligninsulfonate, tall (pine) oil, vegetable derivatives, and
molasses. Table 3 lists major studies performed on the effectiveness of non-petroleum based products
and polymers to abate dust.
Ligninsulfonate is derived from the sulfite pulping process in the paper industry where wood is
processed using sulfuric acid to break down the wood fiber. Lignin is a complex amorphous aromatic
polymer that acts as a binder for the cellulose fibers in wood. It represents 17-33% dry weight of the wood
and is resistant to hydrolysis (Kirk et al., 1980). In the wood pulping process, the wood fiber is the
valuable product and the pulp liquor, which contains lignin, is wasted. This waste liquor is processed
further and neutralized prior to being used as a dust palliative. Ligninsulfonates act as a weak cement by
binding the soil particles together. Ligninsulfonates remains effective during long dry periods with low
humidity. They also tend to remain plastic, allowing reshaping and traffic compaction when applied to
soils with high amounts of clay. The effectiveness of ligninsulfonates may be reduced or completely
destroyed in the presence of heavy rain because of the solubility of these products in water (Bolander,
1999a).
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Table 3 - Effectiveness of non-petroleum based and polymer products as dust suppressants
Suppressant Type
Sprinkling of 40 ml/m2/day
of canola oil on swine barns
Lignin used on unpaved
roads
Ligninsulfonate used to
control dust fungi and
endotoxins in livestock
housing facilities
Synthetic polymer and tall
oil
Polymer emulsion (PE)
Polymer Emulsion (PEP)
Biocatalyst stabilizer (BS)
Effectiveness
Reduction of 84% in dust concentration
63% more aggregates retained as
compared to untreated sections.
Mass of dust, fungi, and endotoxins were
reduced 6, 4, and 3 fold respectively, when
ligninsulfonate solutions (27-39%) were
applied.
Increased tensile strength of soil. Strength
dependent upon curing time.
Initial = 94%, After 3 months = 96%
After 1 1 months = 85%
Initial = 99%, After 3 months = 72%
After 1 1 months = 49%
Initial = 33% - 5%, After 3 months = 0%
After 1 1 months = 0%
Reference
Senthilselvan et a/., 1997
Sanders and Addo, 1993
Breum et a/., 1999
Bolander, 1999b
Gillesefa/., 1997
Gillesefa/., 1997
Gillesefa/., 1997
Tall oil is a by-product of the wood pulp industry recovered from pinewood in the sulfate Kraft paper
process. It contains rosin, oleic and linoleic acids. Tall oil is used in flotation agents, greases, paint alkyd
resins, linoleum, soaps, fungicides, asphalt emulsions, rubber formulations, cutting oils, and sulfonated
oils (Merck Index, 1989). Tall oil promotes adherence between soil particles, however, its surface binding
actions can be limited or destroyed if this product is exposed to long-term rainfall. Increasing the residual
content of tall oil was found to promote an increase in the tensile strength and resistance to periodic
wetting or wet freeze of these products (Bolander, 1999a).
Vegetable oils are extracts from the seeds, fruit, or nuts of plants and are generally a mixture of
glycerides (Lewis, 1993). Some examples of vegetable oils are canola oil, soybean oil, cottonseed oil,
and linseed oil. Vegetable oils abate dust by promoting agglomeration of the surface particles.
Molasses is the thick liquid left after sucrose has been removed from the mother liquor in sugar
manufacturing. It contains approximately 20% sucrose, 20% reducing sugar, 10% ash, 20% organic non-
sugar, and 20 % water (Lewis, 1993). This type of dust suppressant provides temporary binding to the
surface particles (Bolander, 1999a). Additional applications are necessary during the year, mainly after
heavy rains, because molasses will dissolve in water (Sanders and Addo, 1993).
Synthetic Polymer Products
The adhesive property of synthetic polymers promotes the binding of soil particles. Products such as
polyvinyl acetate and vinyl acrylic are used in synthetic polymers. In the laboratory, Bolander (1999b)
investigated the effect of adding synthetic polymers to dense-graded aggregate. The results show that
polymers increased the tensile strength of clays on typical roads and trails up to ten times. Synthetic
polymer emulsions did not change the compacted dry density. The tests showed that synthetic polymers
applied in wet climates would tend to break down if exposed to moisture or freezing for an increased time.
Organic Petroleum Products
Organic petroleum-based materials consist of products derived from petroleum. These include used
oils, solvents, cutback solvents, asphalt emulsions, dust oils, and tars. These products agglomerate fine
particles, generally forming a coherent surface that holds the soil particles in place. Petroleum-based
products are not water-soluble or prone to evaporation (Travnik, 1991). They generally resist being
washed away, but oil is not held tightly by most soils and can be leached away by rain. Langdon and
Williamson (1983) divided petroleum based products into different categories: cutbacks (e.g. DO-1, DO-2,
49
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DO-3, and DO-6KF), emulsions (e.g. DO-8, Coherex, and CSS-1), and others (e.g. DO-4, DO-6, DO-6P).
Table 4 lists studies on the effectiveness of petroleum-based products.
Table 4 - Effectiveness of petroleum-based products as dust suppressants
Suppressant Type
Oiling (petroleum-based)
Water (0.44 gal/yd2), petroleum
resin (0.84 gal/yd ), and
emulsified asphalt (0.71 gal/yd2).
Emulsion of hydrocarbon-based
textile oil applied to bulk-stored
wheat, corn, and soybeans
Emulsified petroleum resin,
petroleum residue,
Non-hazardous crude oil (NHCO)
Effectiveness
50 to 98%
50% reduction in particulate emissions for at
least one month. Reapplication increased
suppressant lifetime. Lifetime decreased with
decreasing particle size.
50% reduction (0.04%emulsion)
92% reduction (0.07% emulsion)
Similar results found for rapeseed and oils.
In general, an increase in water content during
suppressant application improved cohesive
strength of the aggregates
Very effective in suppressing dust for a long
period; after 1 1 months = 92% effective
Reference
Foley et al., 1996
Muleski etal., 1983
Jayas etal., 1992
Lane etal., 1983
Gillesefa/., 1997
Electro-Chemical Products
These suppressants are usually derived from sulphonated petroleum and highly ionic products. This
group of products includes sulphonated oils, enzymes, and ammonium chloride. The electro-chemical
stabilizers work by expelling adsorbed water from the soil which decreases air voids and increases
compaction (Foley et al., 1996). A disadvantage of these products is the dependence upon the clay
mineralogy and therefore they are only effective when specific minerals are present.
Clay Additives
Clay additives are composed of silica oxide tetrahedra (SiO4) and alumina hydroxide octahedra
(AI(OH)6) (Scholen, 1995). This type of dust suppressant agglomerates fine dust particles and increases
the strength of the material under dry conditions. Clay additives provide some tensile strength in warm dry
climates; however, increasing the moisture contents promotes loss of their tensile strength (Bolander,
1999b).
Others
In addition to the categories listed in Table 1, several other suppressants and technologies have been
used to abate dust. Foley et al. (1996) reported that dust emissions on unpaved roads could be reduced
significantly even with small reductions in vehicle speed. Over 40% of the dust was reduced when vehicle
speed was decreased from 47 to 31 miles per hour and over 50% was reduced by decreasing vehicle
speed from 40 to19 miles per hour. Applying an asphalt emulsion (sealing) or paving roads has been
shown to reduce dust by 95-100%. Table 5 reports various treatments that have been successfully
applied to unpaved roads to reduce dust.
Table 5 - Effectiveness of various treatments used to suppress dust
Suppressant Type
Sealing or bound paving
Chemical dust suppression
Clay additive, chlorides,
enzymes, and sulfonate
Chemical dust suppression
Reduction of vehicle speed:
from 47 mile/h to 31 mile/h
from 40 mile/h to 19 mile/h
Effectiveness
95-100%
High initial efficiency; it decays to zero after
several months.
Increased tensile strength for moisture contents
less than 5%.
40-98%
40-75%
50-85%
Reference
Foley et al., 1996
Cowherd etal., 1989
Bolander, 1999b
Foley et al., 1996
Foley et al., 1996
50
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Application Rates
Table 6 shows typical application rates for several types of suppressants. Typical application
frequency for most suppressants is 1-2 times per year, except for clay additives for which the application
rate is every 5 years.
Table 6 - Application rates and frequencies of dust suppressants
Suppressant
Calcium chloride
Mg chloride
Ligninsulfonate
Vegetable oils
Oils
Arcadias (DO-1 ,
2, 3), DO-4, DO-
6PA, DO-8,
CSS-1
Coherex
Organic Binders
application rate
Polybind Acrylic
(co-polymer
resin emulsion)
Synthetic
polymer
derivatives
Clay additives
Water
Bituminous and
tars or resinous
adhesives
Range of
Application Rate
0.8-2.0 Ibs/yd2 (dry salt)
0.2 -0.5 gal/yd2 (solution)
0.3-0.5 gal/yd2
0.2 -1.5 gal/yd2 (liquid)
1 .0-2.0 Ibs/yd 2 (powder)
40-50% residual
concentrate applied
diluted 1 :4 w/water at 5.1
gal/yd2
Typically 0.24-0.5 gal/yd2
0.1 -1.0 gal/yd2
n 9 n
-------
Environmental Impacts
Salts and Brines
The potential environmental impacts of salts and brines include corrosion of vehicles and concrete
and creation of a slippery surfaces when wet (Foley et al., 1996). Calcium and magnesium chloride are
highly soluble and are capable of moving with water through soil as a leachate contaminating
groundwater (Heffner, 1997). They can also move as runoff and the dissociated calcium, magnesium and
chloride ions can drain into lakes, rivers, streams, and ponds (Demers and Sage, 1990). High
concentrations of salts cause high soil salinity and may be toxic to plants (Hanes et al., 1970 and 1976);
Sanders and Addo; 1993, Foley et al. 1996; RTAC, 1987). However, no conclusive studies have been
performed to evaluate the effects of calcium and magnesium chloride on plants. Salts concentrations
greater than 400 ppm have been found to be toxic to trout (Golden, 1991 and Foley et al., 1996).
Concentrations greater than 1,830 mg/L killed Daphnia and crustaceans fish (Sanders and Addo, 1993;
Anderson, 1984).
Organic Non-Petroleum Products
The toxicity of ligninsulfonates to rainbow trout has been investigated. The 48-hour LC50
(concentration of ligninsulfonates which would be lethal to 50 percent of the tested population within 48
hours) value for ligninsulfonates was found to be 7,300 mg/L. A mortality of 50% was achieved for
rainbow trout exposed to 2,500 mg/L ligninsulfonate for 275 hours. For concentrations equal to or higher
than 2,500 mg/L rainbow trout showed loss of reaction to unexpected movements, rapid and irregular
breathing, and finally loss of coordination before death (Roald, 1977a; Roald, 1977b). It has been found
that calcium and sodium ligninsulfonate negatively affect the colon of guinea pigs causing weight gain
and producing ulceration in those animals (Watt and Marcus, 1974 and 1976). Reduced biological activity
has been observed in water due to excessive discoloration caused by the introduction of ligninsulfonates
(Singer et al., 1982; Raabe, 1968; Heffner, 1997; Foley et al., 1996). Ligninsulfonate compounds were
reported not to prevent seed germination in the areas where it was applied (Singer et al., 1982). It has
been suggested that ligninsulfonate is the most environmentally compatible dust suppressant
(Schwendeman, 1981).
Organic Petroleum Products
Organic petroleum based products are considered long lasting products for dust suppression.
However, since some of them are oil waste, their environmental impacts may be high. Waste oil used as
dust suppressant is typically associated with contaminants that are known to be either toxic or
carcinogenic (RTAC, 1987; Metzler, 1985; USEPA 1984, Foley et al., 1996). The accidental introduction
of a petroleum based dust suppressant (Coherex) into a stream in Southern Pennsylvania was found to
affect fish and benthic macroinvertebrate communities and to kill an unknown number of fish (Ettinger,
1987). Organic petroleum-based products have also been found to be toxic to avian Mallard eggs. When
the eggs were exposed to a concentration of 0.5 /
-------
Table 7 - Reported dust suppressant costs
Suppressants
Calcium Chloride
Magnesium chloride
Ligninsulfonate
Arcadia DO-1
Arcadia DO-2
Arcadia DO-4
Arcadia DO-6KF
Arcadia DO-6PA
Arcadia DO-8
Coherex (concentrate)
CSS-1
Bulk Product Cost
$114.00/ton-$273.00/ton
$195 per dry ton
$67. OO/ton-1 82 gal/ton
$40.00/ton
$210.00/ton
$210.00/ton
$175.00/ton
$215.00/ton
$152.75/ton
$150.00/ton
$285.60/ton
$150.00/ton
Reference
Langdon and Williams, 1983
Hoover, 1981
Langdon and Williams, 1983
Langdon and Williams, 1983
Langdon and Williams, 1983
Langdon and Williams, 1983
Langdon and Williams, 1983
Langdon and Williams, 1983
Langdon and Williams, 1983
Langdon and Williams, 1983
Langdon and Williams, 1983
Langdon and Williams, 1983
Suppressants
Chlorides
Calcium chloride cost/mile at a 21 -ft
width and 2 Ib/yd2
Chlortex(MgCI2)
ESI-Duster
Dustac (Ligninsulfonate)
Ligninsulfonate cost/mile length and 21-
ft width
Organic Binders
Petroleum Binder
PennzsuppressD (petroleum resin)
Surfactants
Polymeric Binders
Polytex (acrylic polymer emulsion)
Soil-Sement (acrylic polymer emulsion)
Plastex (paper mulch + gypsum binder)
Hydroseed (wood fiber mulch + brome
seed)
Recycled Aggregate
Ionic Stabilizers
Microbiological Binders
$ Cost/acre
$283-$2,023/ acre
£165
$600/acre
$9800 (bag of 50 Ibs)
$750/acre
£350 ($800-$900)
$1011-$24282/acre
$2023-$5261/acre
$800/acre
< $1619/acre
$6475/acre
$700/acre
$1 050/acre
$850/acre
$1 ,200/acre
$13,500/acre
$1,214-$4,047/acre
$3,642/acre
Reference
Foley et a/., 1996
Hoover, 1981
James et a/., 1999
Langdon and Williams, 1983
James et a/., 1999
Hoover, 1981
Foley et a/., 1996
Foley et a/., 1996
James et a/., 1999
Foley et a/., 1996
Foley et a/., 1996
James et a/., 1999
James et a/., 1999
James et a/., 1999
James et a/., 1999
James et a/., 1999
Foley et a/., 1996
Foley et a/., 1996
53
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54
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Appendix A References
Anderson, B.C., 1984. The Apparent Thresholds of Toxicity of Daphnia magna for Chlorides of Various
Metals When Added to Lake Erie Water, American Fisheries Society, Vol. 78, pp 96-113.
Bolander, 1999a. Dust Palliative Selection Application Guide, United States Department of Agriculture.
Bolander, P., 1999b. Laboratory Testing of Nontraditional Additives for Stabilization of Roads and Trail
Surfaces, Transportation Research Board, Proceedings from the Seventh International Conference
on Low-Volume Roads, Transportation Research Record No. 1652, Volume 2, Washington, DC.
Breum, N.O., Nielsen, B.H., Lyngbye, M., 1999. Dustiness of Chopped Straw as Affected by
Ligninsulfonate as a Dust Suppressant, Annals of Agriculture and Environmental Medicine: AAEM,
Vol.6, No. 2, pp 133-140.
Cal/EPA, 2001. Evaluation of the Pennzoil-Quaker State Company's PennzSuppress D Dust
Suppressant, California Environmental Protection Agency - Environmental Technology Certification
Program, certificate No. 00-08-001.
Cowherd Jr., C., Elmore, W.L., Durkee, K.R., 1989. Potential Regulatory Approaches for the Control of
PM-10 Emissions From Urban Dust Sources, Air and Waste Management Association Meeting. In:
Proceedings of the 82nd Annual Meeting and Exhibition, from June 25-30, Vol. 3, Anaheim, California.
DeCastro, A., Edgar, T.V., Foster, D. H., and Boresi, A.P., 1996. Physical and Chemical Stability of
Admixtures in Unpaved Road Soils. North Dakota State University, Bismarck, North Dakota.
Demers, C.L., Sage Jr., R.W., 1990. Effects of Road De-icing Salt on Chloride Levels in Four Adirondack
Streams, Water, Air, and Soil Pollution, Vol. 49, pp 369-373.
Dirt and Gravel Roads Maintenance Program (DGRM), Pennsylvania, 2000. Center for Dirt and Gravel
Road Studies, Penn State University.
Environmental Canada, http://www.etvcanada.com/English/e_home.htm, ETV Canada Inc.
Ettinger, W.S., 1987. Impacts of a Chemical Dust Suppressant/Soil Stabilizer on the Physical and
Biological Characteristics of a Stream, Journal of Soil and water Conservation, Vol. 42, No. 2, pp 111-
114.
ETV/USEPA, 2001. Generic Verification Protocol for Dust Suppression and Soil Stabilization Products,
ETV Joint Verification Statement - The Environmental Technology Verification Program - Research
Triangle Institute.
Foley, G., Cropley, S., and Giummara, G., 1996. Road Dust Control Techniques - Evaluation of Chemical
Dust Suppressant's Performance, ARRB Transport Research Ltd., Special Report 54, Victoria,
Australia.
Gebhart, D.L., Denight, M.L., Grau, R.H., 1999. Dust Control Guidance and Technology Selection Key.
U.S. Army environmental Center- U.S. Army Corps of Engineering, AEC Report No. SFIM-AEC-EQ-
CR-99002.
Gilles, J.A., Watson, J.G., Rogers, C.F., Chow, H.C., 1997. PM10 Emissions and Dust Suppressants
Efficiencies on an Unpaved Road, Merced County, CA. In: Proceedings of the Air and Waste
Management Association's 90th Annual Meeting and Exhibition, June 8-13, Toronto, Ontario, Canada.
55
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Gilles, J. A., Watson, J. G., Rogers, C. F., DuBois, D., Chow, J. C., Langston, R., Sweet, J., 1999, Long-
term Efficiencies of Dust Suppressants to Reduce PM10 Emissions from Unpaved Roads, Journal of
the Air and Waste Management Association, Vol. 49.
Goldbeck, L.J., 1997. Improving Plant Competitiveness Through Conveyor Dust Control Technologies. In
Proceedings
pp 600-605.
Proceedings of the 59th Annual American Power Conference (Part 2), Volume 59-II, Chicago, Illinois,
Golden, B.J., 1991. Impact of Magnesium Chloride Dust Control Product on the Environment, In:
Proceedings of the Transportation Association of Canada Annual Conference, Volume 1, Winnipeg,
Manitoba.
Hanes, R.E., Zelanzny, L.W., and Blaser, R.E., 1970. Effects ofDeicing Salts on Water Quality and Biota.
National Cooperative Highway Research Program, Report No. 91.
Hanes, R.E., Zelanzny, L.W., Verghese, K.G., Bosshart, R.P., Carson Jr., E.W., Wolf, D.D., 1976. Effects
of Deicing Salts on Plant Biota and Soil. National Cooperative Highway Research Program, Report
No. 170.
Heffner, K., 1997, Water Quality Effects of Three Dust-Abatement Compounds, Washington Forest
Service, United States Department of Agriculture.
Hoffman, D.J., Eastin, W.C., 1981. Effects of Industrial Effluents, Heavy Metals, and Organic Solvents on
Mallard Embryo Development, Toxicology Letters, Volume 9, No. 1, pp 35-40.
Hoover, J.M., 1981. Mission-Oriented Dust Control and Surface Improvement Processes for Unpaved
Roads, Final Report, Iowa Highway Research Board Project, H-194.
Interim Guidelines on Dust Palliative Use in Clark County, 2001. State of Nevada, Department of
Conservation and Natural Resources- Division of Environmental Protection.
James, D., Pulgarin, J., Gingras, T., Edwards, S., Venglass, G., Becker, J., Licon, A., Swallow, C.,
Gambatese, J., Luke, B., 1999. Field Testing of Dust Suppressants Using a Portable Wind Tunnel.
Final Report for Clark County Health District.
Jayas, D.S., White, N.D.G., Britton, M.G., 1992. Effect of Oil Used for Dust Control on Engineering
Properties of Stored Wheat, American Society of Agricultural Engineers, Vol. 35, No. 2, pp 659-664.
Kestner, M., 1989. Using Dust Suppressants to Control Dust Emissions - Part 1, Powder and Bulk
Engineering, Vol. 3, No. 2.
Kimball, C.E., 1997. Evaluating Groundwater Pollution Susceptibility of Dust Suppressants and Roadbed
Stabilizers: Case Study of a Petroleum-based Product. Transportation Research Record 1589, 64-49.
Kirk, T.K., Higuchi, T., Chang, H., 1980, Lignin Biodegradation: Microbiology, Chemistry, and Potential
Applications, Volumes I and II, CRC Press, Inc., Boca Raton, Florida.
Kuula-Vaisanen, P., Jarvinen, H.L., Nieminen, P., 1995. Calcium Chloride in Road Construction. In: Sixth
International Conference on Low-Volume Roads, Minneapolis, Minnesota, June 25-29, 1995,
Conference Proceedings No. 6, Vol. 2, PP 225-233 (Transportation Research Board: Washington,
DC).
Lane, D.D., Baxter, T.E., Cuscino, T., and Cowherd Jr., C., 1983. Use of Laboratory Methods to Quantify
Dust Suppressant Effectiveness, Society of Mining Engineers of AIME, Vol. 274.
Langdon, B., and Williamson, R.K., 1983. Dust Abatement Material: Validation and Selection,
Transportation Research Record 898, pp 250-257.
56
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Lewis, R.J., 1993, Hawley's Condensed Chemical Dictionary, Twelfth edition.
Michigan Department of Environmental Quality (MDEQ), 2000. Waste Management Division. Ground-
water Discharge General Permit - 221500-5. www.deq.state.mi.us/documents/deq-wmd-gwp-
Rule2215OilFieldBrine-1 .pdf
Merck Index, 1989, The Merck Index, Eleventh Edition, Merck & Co., Inc., Rahway, New Jersey, USA.
Metzler, S. C., Jarvis, C., 1985. Effects of Waste Oil Contamination, Environmental Progress, Vol. 4,
Issue 1, pp 61-65.
Monlux, S., 1993. Dust Abatement Product Comparison in the Northern Region, Engineering Field Notes,
USDA Forest Service, Vol. 25.
Muleski, G.E., Cowherd Jr., C., 1987, Evaluation of the Effectiveness of Chemical Dust Suppressants on
Unpaved Roads, Document No. EPA-600/2-87-102, Air and Engineering Research Laboratory, U.S.
Environmental Protection Agency, Research Triangle Park, NC.
Muleski, G.E., Cuscino Jr., T.A., Cowherd Jr., C., 1983. Definition on the Long-term Control Efficiency of
Chemical Dust Suppressants Applied to Unpaved Roads. In: Proceedings of the Air pollution
Association 76th APCA Annual Meeting, June 19-24, Atlanta, Georgia.
Nevada Department of Environmental Protection (NDEP), 2001. Interim Guidelines on Dust Palliative Use
in Clark County. State of Nevada, Department of Conservation and Natural Resources - Division of
Environmental Protection.
Raabe, E.W., 1968. Biochemical Oxygen Demand and Degradation of Lignin in Natural Waters, Journal
Water Pollution Control Federation, Vol. 40, pp R145-R150.
Roald, S.O., 1977a. Effects of Sublethal Concentrations of Lignosulfonates on Growth, Intestinal Flora
and some Digestive Enzymes in Rainbow Trout, Aquaculture, Vol.12, pp 327-335.
Roald, S.O., 1977b. Acute Toxicity of Ligninsulfonates on Rainbow Trout, Bulletin of Environmental
Contamination and Toxicology, Vol.17, No. 6, Springer-Verlag, New York Inc.
Road and Transportation Association of Canada (RTAC), 1987, Guidelines for Cost Effective Use and
Application of Dust Palliatives.
Sanders, T.G., Addo, J.Q., Ariniello, A., and Heiden, W.F., 1997. Relative Effectiveness of Road Dust
Suppressants, Journal of Transportation Engineering, Vol.123, No. 5.
Sanders, T.G., and J.Q. Addo, 1993. Effectiveness and Environmental Impact of Road Dust
Suppressants, Mountain-Plains Consortium, MPC-94-28.
Satterfield, C.G., Ono, D., 1996, Using Magnesium Chloride in Street Sweepers to Control PM-10
Emissions from Winter-Time Sanding of Roadways, Air and Waste Management Association, In:
Proceedings of the 89th Annual Meeting and Exhibition, June 23-28, Nashville, Tennessee.
Scholen, D.E., 1995. Stabilizer Mechanisms in Nonstandard Stabilizers, In: Sixth International
Conference on Low-Volume Roads, Minneapolis, Minnesota, June 25-29, Conference Proceedings
No. 6, Vol. 2, PP 252-260 (Transportation Research Board: Washington, DC).
Schwendeman, T.G., 1981. Dust Palliative Evaluation - Part II. USDA Forest Service, Gallatin National
Forest.
Senthilselvan, A., Zhang, Y., Dosman, J.A., Barber, E.M., 1997. Positive Human Health Effects of Dust
Suppressants with Canola Oil in Swine Barns, American Journal of respiratory and Critical care
Medicine, Vol. 156, pp 410-417.
57
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Singer, R.D., Stevens, J.R., Gleason, J.R., Baker, D.A., Baker, T.M., and McEmber, A.V., 1982. An
Environmental Evaluation of Dust Suppressants: Calcium Chloride and Ligninsulfonate. United States
Department of Interior Bureau of Mines.
Thompson, G.L., 1990, Dust Suppression Systems for Controlling Dust from Coal Handling Systems in
Power Plants, Fuel Strategies Coal Supply, Dust Control, and Byproducts Utilization, The 1990
International Joint Power Generation Conference Boston, Massachusetts, The American Society of
Mechanical Engineers, Volume 8.
Travnik, W.A., 1991. State of Art Dust Suppressants/Soil Stabilizers, In: Proceedings of the 42nd Annual
Road Builders' Clinic, March 5-7, Coeur D'Alene, Idaho, pp. 39-61
USEPA, 1984. Hazardous and Solids waste amendments of 1984 (HSWA), Section 213 Amended
Section 3004 of RCRA - Ban the use of hazardous waste and materials mixed with hazardous waste
as dust suppressants.
U.S. Environmental Protection Agency (USEPA), 2002. Air Trends 1995 Summary -
http://www.epa.gov/oar/aqtrnd95/pm10.html
Watt, J. and Marcus, R., 1974. Effect of Ligninsulfonate on the Colon of Guinea-pigs, Proceedings of the
Nutrition Society, Vol. 33, pp 65A-66A.
Watt, J. and Marcus, R., 1976. Effect of Various Salts of ligninsulfonate on the colon of Guinea-pigs,
Proceedings of the Nutrition Society, Vol. 35, pp 76A.
58
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Appendix B
Fact Sheets for Verification Programs and Guidelines
59
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60
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university of
nevada las vegas
Environmental Technology Verification Program
California Environmental Technology
Certification Program (CalCert)
May 2002
Responsible Agency What are the goals of CalCert?
California Environmental
Protection Agency
Environmental Technology
Certification Program
Contacts
Air Resources Board:
Hafizur Chowdhury
(916)327-5626
hchowdhu@arb.ca.gov
www.arb.ca.gov
State Water Resources:
Bryan Brock
(916)227-4574
brockb@cwp.swrcb.ca.gov
www.swrcb.ca.gov
References
www.calepa.ca.gov/calcert
Disclaimer: This fact sheet
was prepared by the UNL V
organizing committee of the
"Expert Panel on
Environmental Impacts of
Dust Suppressants" based on
information contained in the
above reference.
The California Environmental Technology Certification Program (CalCert) is
the umbrella program for all technology certifications within the California
Environmental Protection Agency (Cal/EPA). CalCert is a voluntary program
for manufacturers seeking independent evaluation and certification of the
performance of their environmental technology including dust suppressants.
Certification efforts within the California Environmental Protection Agency
(Cal/EPA) are authorized under section 71031 of the California Public
Resources Code.
Who created CalCert?
In 1993, Cal/EPA and the Trade and Commerce Agency created the
California Environmental Technology Partnership (CETP), a public-private
partnership comprising of representatives from the financial and legal
communities, public interest groups, the technology industry, laboratories,
academia, and others. Among several strategies to strengthen California's
environmental technology industry, CETP recommended Cal/EPA institute a
voluntary statewide certification program for environmental technologies.
Following enactment of Assembly Bill 2060 (Chapter 429, Statutes of 1993)
and Assembly Bill 3215 (Chapter 412, Statutes of 1994), Cal/EPA imple-
mented two voluntary pilot certification projects: one for hazardous waste-
related technologies at the Department of Toxic Substances Control and
another for air pollution control at the Air Resources Board. After two
successful pilot programs, and enactment of Assembly Bill 1943 (Chapter
367, Statutes of 1996), CalCert expanded to address a broad array of
technologies that prevent, treat, or cleanup pollution in air, water, and soil.
The program seeks to maintain and advance high environmental standards by
assuring that the best possible environmental technology is available to meet
those high standards.
Who provides the performance verification?
Technology developers and manufactures define their performance claims
and provide supporting documentation; Cal/EPA reviews that information and,
where necessary, requires additional testing to verify the claims. Participation
in the program generally involves four stages: eligibility request, application
and data review, evaluation of test data, evaluation report, certification
decision or statement, and certificate issuance.
Who may apply for verification?
Equipment, processes or products eligible for certification must have an
environmental benefit, be commonly used or readily available, and not pose a
significant potential hazard to public safety and the environment. Furthermore,
applicants for the program must demonstrate that they can consistently and
reliably produce technologies that perform at least as well as those previously
considered in the CalCert evaluations.
61
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What is needed to apply?
To apply to the program the applicant should hold manufacturing rights to the technology. The technology
should be commercially ready with available quality testing data to support performance claim. The first step
to have a technology certified is to request for a determination of eligibility. After CalCert has received the
Eligibility Request and determined that the technology is eligible for California Certification, the applicant will
receive an Application for Certification and will be invited to meet the Cal/EPA evaluation team in a scoping
meeting. The evaluation team will meet with the applicant to discuss the scope, duration, and cost of the
evaluation. The cost of evaluating the technology will vary depending on the scope of effort needed to
evaluate it.
Who evaluates the application for verification?
Cal/EPA's staff which consist of scientists and engineers from the Air Resources Board, State Water
Resources Control Board, Department of Toxic Substances Control, Integrated Waste Management Board,
Department of Pesticide Regulation, and Office of Environmental Health Hazard Assessment evaluate the
technologies. When necessary, CalCert also partners with California's universities and laboratories.
What are the criteria for verification?
The products eligible for certification must have an environmental benefit, be commonly-used or ready
available, and not pose a significant potential hazard to public safety and the environment. The evaluation is
based on a detailed review of validation materials submitted by the manufacturer, including original data
generated by independent and in-house laboratories, whose findings are considered reliable by Cal/EPA staff.
What is the proof of verification?
A certificate signed by California's Secretary for Environmental Protection is awarded. The issuance of the
evaluation report and certificate authorizes the use of the certified technology seal on certified products. The
CalCert's certification is valid for three years. Certification does not imply that the technology has been
permitted by any application.
What dust suppressants have been certified by CalCert?
In January, 2001 the California Environmental Protection Agency staff recommended certification of
PennzSuppress® D, an organic based product from the Pennzoil-Quaker State Company, as a dust
suppressant. The certification is valid for three years.
62
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Application of Oil Field Brine Regulations
Michigan
university of
nevada las vegas
Responsible Agency
Michigan Department of
Environmental Quality Waste
Management Division
Contacts
Lonnie C. Lee
Waste Management Division
Michigan Department of
Environmental Quality
Address:
P.O. Box 30241
Lansing Ml 48909-7741
Phone:(517)373-8148
References
www.deq.state.mi.us/documents/
deq-wmd-qwp-
Rule22150ilFieldBrine-1.pdf
Disclaimer: This fact sheet was
prepared by the UNLV organizing
committee of the "Expert Panel
on Environmental Impacts of Dust
Suppressants" based on
information contained in the
above reference.
May 2002
What are oil field brines?
Brines that are produced at oil and gas well facilities. These brines are used
for dust control and soil stabilization.
How does Michigan regulate the application of oil field
brines?
The Michigan Department of Environmental Quality through regulation
R324.705 (3), Part 615, Supervisor of Wells, of Act 451 requires a permit for
the application of brines for ice and dust control and soil stabilization. Pursuant
to this general permit, applicant of brine may begin as soon as the conditions
of the general permit have been met. All maintenance, operations, and
monitoring of brine application must comply with the conditions set forth in this
general permit by the Department. Failure to comply with the terms and
provisions of this general permit may result in civil and/or criminal penalties as
provided in Part 31.
What are the requirements of the Michigan oil field brine
regulations?
The requirements for oil field application as a dust suppressant and road
stabilizers include:
1. No application can occur until a certificate of authorization of coverage on
a form approved by the Department is issued.
2. Only brine that meets the requirements of R 324.705 (3) of Part 615, as
amended, may be used for ice and dust control and soil stabilization on
land, such as roads, parking lots and other land.
3. To prevent other contaminants from becoming part of the brine discharge,
brine shall be applied with vehicular equipment dedicated to this use or
hauling fresh water.
4. Brine shall be applied for dust control and soil stabilization in accordance
with the following criteria: (a) brine may be applied to the surface of roads,
parking lots, and other land up to four applications each year south of the
southern county lines of Madison, Lake, Osceola, Clare, Cladwin, and
Arenac Counties. Counties north of this line may apply only three times
per year; (b) brine may be applied to the surface of roads being used as a
detour and on other areas during construction as necessary to control dust
up to six applications each year; (c) brine must be applied to roads and
parking areas with equipment described by the term "spreader bar". This
device shall be constructed to deliver a uniform application of brine over a
width of at least eight feet; (d) brine may be applied at a maximum rate of
1,500 gallons per lane mile of road or 1,250 gallons per acre of land,
provided runoff does not occur; (e) Brine shall be applied in a manner to
prevent runoff.
63
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5. Brine shall be applied for dust control and soil stabilization in accordance with the following criteria: (a) brine
may be applied to the surface of roads, parking lots, and other land up to four applications each year south of
the southern county lines of Madison, Lake, Osceola, Clare, Cladwin, and Arenac Counties. Counties north of
this line may apply only three times per year; (b) brine may be applied to the surface of roads being used as a
detour and on other areas during construction as necessary to control dust up to six applications each year; (c)
brine must be applied to roads and parking areas with equipment described by the term "spreader bar". This
device shall be constructed to deliver a uniform application of brine over a width of at least eight feet; (d) brine
may be applied at a maximum rate of 1,500 gallons per lane mile of road or 1,250 gallons per acre of land,
provided runoff does not occur; (e) Brine shall be applied in a manner to prevent runoff.
6. Brine shall be applied for ice control in accordance with the following criteria: (a) brine shall be applied only on
paved roads or paved parking lots; (b) brine shall be applied at a maximum rate of 500 gallons per lane mile of
road or 400 gallons per acre of land; (c) brine must be applied only when the air temperature is above 20°F,
unless used for pre-wetting solid salt; (d) brine must be applied with equipment designed to direct the discharge
to the center of the pavement or high sides of curves.
7. Brine application measurement methods must be used to ensure that the brine application rates are within
described in this general permit.
8. Brine shall not be applied at a location determined to be a site of environmental contamination for chlorides.
9. Records shall be kept of the use of brine and should contain driver's name, location, loading date, source of
brine, date of brine, application, and gallons applied. Records should be kept by the application for a period of
three calendar years after application and should be available for inspection by the Department or a peace
officer.
64
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university o
nevada las vega
Responsible Agency
Clark County Department of Air
Quality Management
Nevada Department of
Environmental Protection
(NDEP)
Contacts
Carrie MacDougall
Phone: (702) 455-5942
MacDougall@co.clark.nv.us
Leo Drozdoff (NDEP)
Phone:(775)687-3142
References
www.state,nv.us/cnr/
Disclaimer: This fact sheet was
prepared by the UNLV
organizing committee of the
"Expert Panel on Environmental
Impacts of Dust Suppressants"
based on information contained
in the above reference.
Interim Guidelines for
Dust Palliative Use in Clark County
Nevada
May, 2002
What are the goals of the Interim Guidelines?
The Interim Guidelines aim to facilitate the implementation of air quality
fugitive dust controls in a manner that prevents human exposure to harmful
constituents and protects soil and water resources while achieving air quality
objectives. The guidelines outline practices and procedures that should be
followed to ensure compliance with the new Clark County Air Quality regula-
tions (effective January 1, 2001) in a manner that minimizes environmental
impacts.
Who created the Interim Guidelines?
A working group was formed in 2000 to draft interim guidelines for the use of
dust palliatives in Clark County, Nevada. The working group, formed in
response to direction from the Nevada Legislature to provide recommend-
ations regarding the use of dust suppressants in the Las Vegas Valley, was
composed of air and water quality professionals from state and local agencies
including the Southern Nevada Water Authority, Clark County Health District,
Clark County Comprehensive Planning, Clark County Regional Flood Control
District, City of Las Vegas, UNLV Department of Civil and Environmental
Engineering and the Nevada Department of Environmental Protection (NDEP).
What were the bases for the guidelines?
The working group considered existing state regulations and codes that could
apply to the use of dust palliatives and the protection of human health and
environment. However, because the environmental impacts of the various dust
suppressant products have not been fully evaluated, the working group de-
cided that it would not be prudent to recommend or deny the use of dust
palliatives based solely on these regulations. Thus, the group also considered
currently available scientific information. The guidelines are expected to be
revised in the future to reflect public comments, advanced thinking of the work-
ing group, and changing technology of the construction industry. A research
project, currently underway at UNLV and funded by local agencies, will provide
additional scientific evaluation of the water quality impacts of dust palliatives.
The Dust Palliative Working group will continue to meet on a regular basis to
evaluate pertinent information relating to the environmental impacts of dust
palliative use. It is envisioned that a permanent policy or set of regulations will
be developed if such action is deemed necessary and that this policy/set of
regulations will be more comprehensive in scope.
What is the content of the guidelines?
(a) The use of organic petroleum products, deliquescent/hygroscopic salts,
and lignin-based palliatives are highly discouraged within twenty (20)
yards of open bodies of water, including lakes, streams, canals, natural
wastes and flood control channels, and drinking water well-heads. This
buffer zone is intended to prevent leachate from these palliatives from
reaching an open body of water or a ground water aquifer;
65
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(b) The use of surfactants containing phosphates is highly discouraged because of adverse impacts on water
quality. Surfactants by themselves are not allowed for use as a dust palliative because they do not form a
durable soil surface. Non-phosphate surfactants may be combined with dust palliatives to assist penetration of
dust palliatives into hydrophobic soils;
(c) Any person who applies any pesticide material with a dust palliative is required to hold a valid pesticide
applicators license issued by the State of Nevada;
(d) Fiber mulch products should not be used for use as a dust palliative in traffic areas. These products do not
hold up well for traffic use;
(e) Use of deliquescent/hygroscopic salts should be limited to magnesium chloride and only used for short-term
(less than one year) stabilization of unpaved roads. Treated unpaved roads must be periodically maintained
with additional applications of water and magnesium chloride as needed to maintain effectiveness.
Magnesium chloride is not effective, even with product reapplication, for periods of more than one year.
Magnesium chloride should not be used on trafficked areas within twenty (20) yards of an open body of water,
a drinking water well-head, natural or artificial drainage channel, or other surface water feature;
(f) Organic petroleum products, including modified and unmodified asphalt emulsions, should not be used on
non-traffic areas;
(g) Use of deliquescent/hygroscopic salts is highly discouraged for non-traffic stabilization. These salts require
frequent re-watering to be effective in the Las Vegas Valley;
(h) Lignin-based palliatives are not recommended for non-traffic stabilization. Surface binding action of lignin-
based palliatives may be reduced or completely destroyed when heavy rains occur;
(i) Suppressants containing banned pesticides, restricted pesticides, dioxin, PCBs, and asbestos should never
be applied.
The guidelines also contain recommendations on the types of suppressants to be applied to specific areas as well
as dilution and application rates.
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Dirt & Gravel Roads Maintenance (DGRM) Program
Pennsylvania
university o
ne¥ada las vega:
Responsible Agency What is the DGRP Program?
Center for Dirt and Gravel
Road Studies
Penn State University
Contacts
Barry Scheetz
se6@psu.edu
Woodrow Colbert
wcolbert@psu.edu
Address:
103 Materials Research
Laboratory
Pennsylvania State University
University Park, PA 16802
Phone:(814)865-5355
References
www.mri.psu.edu
Disclaimer: This fact sheet
was prepared by the UNLV
organizing committee of the
"Expert Panel on
Environmental Impacts of
Dust Suppressants" based on
information contained in the
above reference.
Pennsylvania's State Conservation Commission Dirt & Gravel Roads Pollution
Prevention Program is a grant program. It is an innovative effort to educate the public
about pollution problems from roads and fund "environmentally sound" maintenance of
unpaved roadways that have been identified as sources of dust and sediment
pollution. Signed into law in April 1997 as Section 9106 of the PA Vehicle Code (§
-------
Who provides the performance verification?
It is the responsibility of the vendor, as a condition of sale, to prove that the commercial product does not degrade the
environment or create hazards in accordance with the standards of the DGRP program. The vendor has to have an
EPA-Certified laboratory test the product according to the specified test procedures. Laboratory personnel complete the
tests, certify the results, and report the eligibility of the product for program funding in writing. The Conservation
Commission (SCC) will review the submission to confirm the certificate as authentic. The manufacturer must also (a)
certify that the product submitted for testing is representative of the product as marked, (b) provide a copy of the
certificate of eligibility to the conservation district, (c) provide the participant with a signed copy of a liability contract
assuming all liability for supply, transport, application and curing of the product. The product must also comply with
Pennsylvania's environmental laws: 25 PA Code 93.6 - Waste Discharge to Water; 25 PA Code 93.7c - Water Quality
Criteria by Substance; 25 PA Code - Criteria by Toxic Substances; 25 PA Code 121.1 - Air Quality Criteria; 25 PA
Code 124 - Air Quality Hazardous; 25 PA Code 129.64 Air Quality Cut Back Asphalts. In addition, the program
encourages the use of by- and co-products if they are deemed to have non-pollution characteristics. Co-products that
have "beneficial use" permits issued are considered as effective as commercial products if they meet the non-pollution
criteria.
What tests are required from the applicant?
Labeled products, such as herbicides, do not require further testing and are acceptable according to the label
restrictions. Plant and seeds are covered by both, the State and Federal Noxious weed laws. All other commercial
products, which are not inert, must be certified. The guidelines divide the products used in dirt and gravel roads into
solids (e.g. stone, geotextile, salts as crystals) and aqueous (e.g. brines, emulsions). Aqueous products must undergo
the following required tests: a 7-day rainbow trout survival and growth test, and a 7-day cladoceran (Ceriodaphinia
dubia) survival and reproduction test. Each product tested must report the NOEC, LOEC, LC50 and CHV values for the
survival and growth of rainbow trout and one for the survival and reproduction of cladocerans. An MSDS sheet for each
product should accompany the application. In addition, the materials have to undergo bulk and leach analysis. Bulk
analysis should follow methods established in EPA SW-846 and leach analysis should be performed according to EPA
Method 1312. Components analyzed in these tests include: pH, major, minor, and trace components, radionuclides,
moisture content, loss of ignition (LOI) at 1000°C, metals, cyanide, volatile, and non-volatile organic compounds. The
laboratory has to report each constituent that exceeds the trigger levels (50% of SPLP limits, as set forth in current PA
DEP Mining Regulations Module 25). If any trigger level (s) is exceeded, a second sample of the material should be
tested.
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Environmental Technology Verification Program
ETV Canada Inc.
university of
nevada las vegas
May 2002
Responsible Agency
ETV Canada Inc.
Contacts
Chris Shrive
(905) 336-4773
cshrive@etvcanada.com
Lori Lishman
(905) 336-6469
lishman@etvcanada.com
Deborah McNairn
(905) 336-4546
dmcnairn@etvcanada.com
Address:
867 Lakeshore Road
Burlington, Ontario
L7R 4A6
Phone: (905) 336-4546
Fax:(905)336-4519
E-mail: etv@etvcanada.com
References
www. etvca n ad a. co m
Disclaimer: This fact sheet
was prepared by the UNLV
organizing committee of the
"Expert Panel on
Environmental Impacts of
Dust Suppressants" based on
information contained in the
above reference.
What are the goals of the ETV Canada Program?
The main objective of the ETV Canada Program is to provide validation and
independent verification of environmental technology performance, including that
of dust suppressants. This program has been developed to promote the commer-
cialization of new environmental technologies into the market place and thus
provide industry with a tool to address environmental challenges efficiently,
effectively and economically.
Who created the ETV Canada?
Environment Canada was the lead department in the development of the ETV
program in cooperation with Industry Canada and with direction from the ETV
Steering Committee. ETV Canada, Inc., a private sector company that operates
under a license agreement with Environment Canada, was created to deliver the
ETV program. The ETV Canada, Inc. is owned by the Ontario Centre for
Environmental Technology Advancement (OCETA).
What is needed to apply?
The technology vendor must provide sufficient, acceptable documentation and
data to support the performance claim of the technology being verified. ETV
Canada reviews the Formal Application for completeness and determines if it can
be accepted into the verification process. If the application is not acceptable, the
applicant may choose to modify and resubmit it. Similarly, at this application
review stage, ETV Canada may determine that the data supporting the claim is
inadequate. If the applicant wishes to continue, it is their responsibility to first
arrange and pay for the generation of the necessary data. Alternatively, the
applicant may choose to modify their claim to align it with supporting data.
Although ETV Canada would not be directly involved in the testing to develop
additional data, it may outline the data requirements within the context of the
General Verification Protocol. The formal application should be accompanied with
the supporting data that is to be used in the verification process. Before
confidential information or data can be passed to ETV Canada, a Confidentiality
Agreement is signed. ETV Canada reviews the information and proposes a
verification process for the claim, including identification of a Verification Entity
and a cost estimate for the verification program. The cost of verification will
include the administration and management of the application process by ETV
Canada and the actual validation by the Verification Entity of the claim, using the
supporting data. The cost will vary from application to application, and will depend
on the scope of effort involved in the verification process. ETV Canada discusses
the scope and cost of the proposed program with the applicant, and reaches
agreement on the Verification Entity, including resolution of any conflict of interest
between the applicant and the Verification Entity. ETV Canada keeps a list of
approved Expert Entities, which include private consultants, universities, and
research institutes that can conduct tests to support the verification of the
technology.
69
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Who provides the performance verification?
A formal application must be submitted to ETV Canada, Inc. for review in order to obtain technology verification. If
the technology and performance claim are eligible for the ETV program, the applicant submits a Formal
Application and a non-refundable $1,000.00 application fee. The Formal Application requests additional
information about the technology, the claim to be verified, and the data and information that is available to support
the claim. The Formal Application is available either by regular mail or electronically by e-mail and can be faxed
back to ETV Canada with a signature. An original should follow by regular mail or by courier with the $1,000.00
fee.
Who may apply for verification?
Environmental technology vendors can apply to the ETV program for verification of the claims concerning the
performance of their environmental technologies. For a technology to be eligible for the ETV program, it must be
an environmental technology or an equipment-based environmental service, where equipment performance can
be verified. The technology must offer an environmental benefit or address an environmental problem. It must also
meet minimum Canadian standards and/or national guidelines for the specific technology or claim, as specified by
ETV Canada, and be currently commercially available or commercially ready for full-scale application.
Who evaluates the application for verification?
ETV Canada reviews the Formal Application for completeness and determines if it can be accepted into the
verification process. Verification Entities, which are approved by ETV Canada, provide the technical expertise to
evaluate the technology.
What are the criteria for verification?
The claim must specify the minimum performance that is achievable by the technology and must be unambiguous.
It must meet minimum standards and guidelines for the technology. Where federal standards are not available, the
least stringent provincial standard shall apply. Technology must achieve federal, provincial, and/or municipal
regulations or guidelines for discharge waters or treated effluents, soils, sediments, sludge or other solid-phase
materials. ETV Canada will refer to such appropriate standards when assessing the claim. The claim must be
measurable using acceptable test procedures and analytical techniques. It is essential that adequate, relevant,
reliable data and information be provided to support the verification of the environmental technology performance
claim.
What is the proof of verification?
If the claim is verified successfully, the company is issued three documents: a Verification Certificate, a Technol-
ogy Fact Sheet, and a Final Verification Report.
What dust suppressants have been certified by ETV Canada?
In March 1999 Soil Sement®, a synthetic polymer emulsion, was certified by ETV Canada. Three years after
approval, the verification should be renewed and a license renewal fee should be applied.
70
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Appendix C
Expert Panel Agenda
THURSDAY, MAY 30™ , 2002
8:00-8:30 AM REGISTRATION
8:30-9:00 AM INTRODUCTIONS
Welcome and Logistics (Thomas Piechota, UNLV)
Importance of issue to EPA (Jeff van Ee, U.S. EPA)
9:00-9:45 AM FRAMING THE PROBLEM
Introduction of Conceptual Model (David James, UNLV)
Summary of Literature Review (UNLV)
Fact Sheets from other relevant activities, programs, and/or protocols.
9:45 - 10:15 AM PANEL I: WHAT ARE WE DEALING WITH?
What is the composition of the dust suppressant and what are the sources of
these compounds?
How are the dust suppressants applied and at what rates?
Where are dust suppressants applied?
10:15-10:30 AM BREAK
10:30 AM - 12:00 PM PANEL I (continued)
What is the potential for trace levels of contaminants given the source and
composition?
Does the Conceptual Diagram outline all the possible pathways of exposure?
What is known about the fate and transport of various dust suppressants? Are
some pathways relatively more significant sources of exposure than others?
How does the composition of the various dust suppressants change once they are
in the environment?
What is the potential magnitude of dust suppressant application in urban or rural
areas?
12:00 - 1:00 PM LUNCH (hosted by UNLV/EPA in Richard Tarn Alumni Center)
1:00 - 2:45 PM PANEL II: WATER PATHWAY
How are dust suppressants likely to impact surface waters?
What are potential impacts of runoff contaminated with dust suppressants to
surface water quality and human health?
What are potential impacts of runoff contaminated with dust suppressants to
aquatic ecosystems?
What is known about movement of dust suppressants in the vadose zone?
Are dust suppressants likely to impact groundwater?
Does Conceptual Model identify all receptors to water quality?
2:45-3:15 PM BREAK
3:15 - 5:00 PM PANEL III: SOIL AND LANDSCAPE PATHWAY
What are the possible human health or ecological impacts related to soils
contaminated with dust suppressants?
How might application of dust suppressants alter soil properties and effect runoff
and erosion?
How might dust suppressants impact ecological patterns?
How might different dust suppressants change the microbial ecology of local soils?
Does the conceptual model clearly identify all pathways and receptors in the
terrestrial environment?
5:00 - 7:00 PM RECEPTION WITH YUCCA MOUNTAIN BOYS (hosted by UNLV/EPA in Alumni
Center)
71
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FRIDAY, MAY 31™, 2002
8:30-8:45 AM FRAMING THE DAY
8:45 - 9:45 AM PANEL IV: MAGNITUDE OF USE (GROUP DISCUSSION)
9:45-10:00 AM BREAK
10:00 - 11:30 AM WORKING GROUPS (See handout)
11:30 AM - 12:30 PM PRESENTATION OF WORKING GROUPS
Designated spokesperson to summarize working groups findings.
12:30 - 2:45 PM PANEL V: QUESTION AND ANSWER WITH EXPERTS (What do they think?)
2:45-3:00 PM BREAK
3:00 - 4:00 PM PANEL VI: DEVELOPING GUIDELINES AND REGULATIONS
Are current regulations adequate for permitting dust suppressants?
Are existing regulations and test methods adequate to address potential effects of
dust suppressants?
Who should be responsible for tracking use of suppressants?
Should long-term monitoring be conducted to evaluate dust suppressant impacts?
PANEL VII: PATH FORWARD
Recommendations on how best to summarize meeting.
What are the follow-up actions from this meeting?
4:00 PM ADJOURN
72
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Appendix D
Organizing Committee and Expert Panel
73
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74
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Organizing Committee
Piechota, Thomas, Ph.D.
University of Nevada, Las Vegas
Department of Civil and Environmental Engineering
4505 Maryland Parkway, Box 454015
Las Vegas, NV 89054-4015
Title: Assistant Professor
Phone: 702-895-4412
Fax: 702-895-3936
E-mail: piechota@ce.unlv.edu
Batista, Jacimaria, Ph.D.
University of Nevada, Las Vegas
Department of Civil and Environmental Engineering
4505 Maryland Parkway, Box 454015
Las Vegas, NV 89054-4015
Title: Assistant Professor
Phone: 702-895-1585
Fax: 702-895-4950
E-mail: iaci@ce.unlv.edu
James, David, Ph.D.
University of Nevada, Las Vegas
Department of Civil and Environmental Engineering
4505 Maryland Parkway, Box 454015
Las Vegas, NV 89054-4015
Title: Associate Professor
Phone: 702-895-1067
Fax: 702-895-3936
E-mail: daveearl@ce.unlv.edu
Stave, Krystyna, Ph.D.
University of Nevada, Las Vegas
Environmental Studies Department
4505 Maryland Parkway
Las Vegas, NV 89054-4030
Title: Assistant Professor
Phone: 702-895-4833
Fax: 702-895-4436
E-mail: kstave@ccmail.nevada.edu
van Ee, Jeff
EPA National Exposure Research Laboratory
Environmental Sciences Division/ORD
PO Box 93478
Las Vegas, NV 89193-3478
Title: Scientist
Phone: 702-798-2367
Fax:
E-mail: vanee.ieff@epa.gov
Singh, Vivek
Title: Graduate Student, UNLV
E-mail: vivek@unlv.edu
Loreto, Daniela
Title: Graduate Student, UNLV
E-mail: daniloreto@hotmail.com
Facilitator
Michael, Daniel
Neptune and Company
1505 15th Street, Suite B
Los Alamos, NM 87544
Title: Principal
Phone: 505-662-0707 ext 20
Fax: 505-662-0500
E-mail: dmichael@neptuneandco.com
75
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76
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Expert Panel
Amy, Penny, Ph.D.
University of Nevada, Las Vegas
Department of Biological Sciences and Provost's
Office
4505 Maryland Parkway
Las Vegas, NV 89154
Title: Professor & Coordinator for
Special Research Programs
Phone: 702-895-3288
Fax: 702-895-3956
E-mail: amy@ccmail.nevada.edu
Bassett, Scott, Ph.D.
Desert Research Institute
2215 Raggio Parkway
Reno, NV 89502
Title: Post-Doctoral Research Associate
Phone: 775-673-7447
Fax: 775-673-7485
E-mail: sbassett@dri.edu
Bigos, Ken, P.E
U.S. Environmental Protection Agency
Air Division, Region IX,
75 Hawthorne Street
San Francisco, CA 94105
Title: Associate Director
Phone: 541-225-6350
Fax: 541-225-6221
E-mail: bigos.ken@epa.gov
Bolander, Peter
USDA Forest Service
211 East 7th Avenue
Eugene, OR 97401
Title: Pavement Engineer
Phone: 541-465-6708
Fax: 541-465-6717
E-mail: pbolander@fs.fed.us
Colbert, Woodrow
Pennsylvania State Conservation Commission
613 South Burrowes Street
State College, PA 16801
Title: Statewide Coord. - Dirt & Gravel Road
Pollution Prevention Program
Phone: 717-497-5164
Fax: 814-863-6787
E-mail: wcolbert@psu.edu
Detloff, Cheryl
Midwest Industrial Supply, Inc.
1101 Third Street SE
Canton, OH 44707
Title: Chief Environmental Chemist
Phone: 330-456-3121
Fax: 330-456-3247
E-mail: chervl@midwestind.com
Franke, Deborah
Research Triangle Institute
3040 Cornwallis Road
Building 11, Room 408
Research Triangle Park, NC 27709
Title: Senior Research Environmental Scientist
Phone: 919-541-6826
Fax: 919-541-6936
E-mail: dlf@rti.org
Hildreth, Troy
Envirocon Mitigation Corporation
8016 Cherish Avenue
Las Vegas, NV 89128
Title: President
Phone: 702-249-2721
Fax: 702-233-4663
E-mail: Troyhildreth@aol.com
Hoffman, Michael, Ph.D.
California Institute of Technology
Environmental Engineering Science
1200 East California Boulevard, M/C 138-78
W. M. Keck Laboratories
Pasadena, CA91125
Title: James Irvine Professor
Phone: 626-395-4391
Fax: 626-395-2940
E-mail: mrh@caltech.edu
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Expert Panel, Continued
Husby, Peter
EPA Region 9 Laboratory
1337 South 46th Street
Building 201
Richmond, CA 94804
Title: Field and Biology Team Leader
Phone: 510-412-2331
Fax: 510-412-2302
E-mail: husby.peter@epa.gov
Johnson, Jolaine, P.E.
Nevada Division of Environmental Protection
333 West Nye Lane
Carson City, NV 89706
Title: Deputy Administrator
Phone: 775-687-9302
Fax: 775-687-5856
E-mail: iolainei@ndep.nv.gov
Kreamer, David, Ph.D.
University of Nevada, Las Vegas
Water Resources Management Program
Department of Geological Sciences
4505 Maryland Parkway
Las Vegas, NV89154
Title:
Phone:
Fax:
E-mail:
Professor and Director of Water
Resources Management Program
702-895-3553
kreamer@nevada.edu
LaBounty, James F. Sr., Ph.D.
920 Bramblewood Drive
Castle Rock, CO 80104-3642
Letey, John, Ph.D.
Soil and Water Science Unit
University of California Riverside
Riverside, CA 92521
Title: Research Aquatic Scientist
Phone: 303-986-7632
Fax: 801-340-5695
E-mail: werlabs@prodigy.net
Lee, G. Fred, Ph.D, P.E., DEE
G. Fred Lee Associates
27298 East El Macero Drive
ElMacero, CA95618
Title: President
Phone: 530-753-9630
Fax: 530-753-9956
E-mail: gfredlee@aol.com
Title: Distinguished Professor of Soil Science
Phone: 909-787-5105
Fax: 909-787-3993
E-mail: john.letey@ucr.edu
MacDougall, Carrie
Clark County Department of Air Quality
Management
500 South Grand Central Parkway
Las Vegas, NV89155
Title: Asst. Director of Air Quality Management
Phone: 702-455-5942
Fax:
E-mail: MacDougall@co.clark.nv.us
Pickrell, John, Ph.D.
Kansas State University
Diagnostic Medicine / Pathobiology, College of
Veterinary Medicine, Comparitive Toxicology
Laboratories
1800 Denison Avenue
Manhattan, KS 66506-5705
Title: Environmental Toxicologist - Associate
Professor
Phone: 785-532-4331
Fax: 785-532-4481
E-mail: pickrell@vet.ksu.edu
Scheetz, Barry, Ph.D.
Penn State University
107 Material Resources Laboratory
University Park, PA 16802
Title: Professor Materials, Civil, & Nuclear Engr.
Phone: 814-865-3539
Fax: 814-863-7039
E-mail: se6@psu.edu
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Expert Panel, Continued
Sanders, Thomas G., Ph.D.
Colorado State University
Department of Civil Engineering
Fort Collins, CO 80523
Title: Associate Professor of Civil Engineering
Phone: 970-491-5448
Fax: 970-491-7727
E-mail: TGS@engr.colostate.edu
Short, Leigh, Ph.D.
Alternative Environmental Solutions
664 Oak Marsh Drive
Mt. Pleasant, SC 29464
Title: Owner/Partner
Phone: 843-971-7462
Fax: 843-881-4485
E-mail: leighche@aol.com
Smith, Roger, Ph.D., P.E.
Consulting Hydraulic Engineer and Hydrologist
819 Columbia Road
Fort Collins, Co 80525
Title: Civil Engineer
Phone: 970-493-2662
Fax: 970-491-8671
E-mail: sroger@engr.colostate.edu
Spear, Terry, Ph.D.
Montana Tech of the University of Montana
1300 West Park Street
Butte, MT 59701
Title: Professor
Phone: 406-496-4445
Fax: 406-496-4650
E-mail: tspear@mtech.edu
Starkweather, Peter, Ph.D.
University of Nevada, Las Vegas
4505 Maryland Parkway
Las Vegas, NV 89154
Title: Professor of Biological Sciences
Phone: 702-895-3526
Fax: 702-895-3861
E-mail: strkwthr@ccmail.nevada.edu
Wells, Jason
ILS, Inc., ESAT Contractor for U.S. EPA Region
4 / Waste Division / Office of Technical Services
61 Forsyth Street SW
Atlanta, GA 30303-8960
Title: Ecological Risk Assessor
Phone: 404-562-8598
Fax: 404-562-9964
E-mail: wells.iason@epamail.epa.gov
Wierenga, Peter, Ph.D.
The University of Arizona
Water Resources Research Center
350 North Campbell Avenue
Tucson, AZ 85721
Title: Director
Phone: 520-792-9591
Fax: 520-792-8518
E-mail: wierenga@ag.arizona.edu
79
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United States
Environmental Protection
Agency
Office of Research and Development
National Exposure Research Laboratory
Environmental Sciences Division
P.O. Box 93478
Las Vegas, Nevada 89193-3478
Official Business
Penalty for Private Use
$300
EPA/600/R-04/031
March 2004
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