v>EPA
United States
Environmental Protection
Agency
Industrial Environmental Research
Laboratory
Cincinnati OH 45268
Research and Development
EPA-600/PS7-80-158 Oct. 1980
Project Summary
Fugitive Dust from Western
Surface Coal Mines
Frank Cook, Arlo Hendrikson, L. Daniel Maxim, and Paul R. Saunders
In this study, field measurements of
fugitive dust levels were made 250 to
500 meters downwind of mining
activities and areas at four surface
coal mines in the Northern Great
Plains during three different climatic
conditions. Ambient dust levels were
also monitored. Wide ranges of
temperature, wind speed, wind
direction, precipitation, soil moisture,
and mining activity levels are
represented in the field data.
Introduction
Some fundamental findings were:
mine-to-mine differences in average
total suspended particulates (TSP)
levels were significant; the evidence for
seasonal differences is weaker, but
consistent with physical theory and
prior judgements; and on the average,
downwind TSP levels were 35 percent
higher than ambient (upwind) levels.
Most strippable western coal is
located in semi-arid, high plains areas
characterized by sparse vegetation,
erodable soils, and high winds. High
ambient dust levels are a result of these
factors. Disturbance of land by surface
coal mining may worsen these dust
conditions.
There exist theoretical models for use
in estimating the dispersion patterns for
paniculate matter emanating from a
point source, such as a power plant
stack. Recently, attempts have been
made to model emission, dispersion,
and deposition of fugitive dust from
point and non-point sources typical of
those from western surface coal mines.
To date, however, there have been few
attempts to apply statistical techniques
to determine empirical relationships
between suspended paniculate levels
in mining areas and explanatory vari-
ables, such as mining activity levels and
meteorological variables. This study
employs such techniques to examine
the effects of mine operations on air
quality under various meteorological
and operational conditions.
It is recommended that a large-scale,
long-term experimental program be
conducted to develop and validate
empirical relationships between total
suspended particulate levels in western
surface coal mining areas and
explanatory variables which measure
the characteristics of the real dust
sources found at such mines. Total sus-
pended particulate levels should be
measured at two or more mines over a
period long enough to ensure that a
wide range of mining and meteorolog-
ical variables are observed. Empirical
results should be systematically com-
pared to those estimated using
published emission factors and
dispersion/deposit ion assumptions.
In brief, the data collection plan
included three visits during different
seasons to each of four surface mines.
Four high volume air samplers were
used to measure dust concentrations
during these visits. Additional data were
collected on soil moisture, weather
conditions, and activity levels of various
mining or mining-related operations.
These data are candidate explanatory
factors to describe the observed vari-
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ability in dust concentrations.
Observations for this project were
taken at several sites within four mines.
Three visits were made to each mine to
ensure that a wide variety of operating
conditions were observed and,
additionally, to study the effect of
seasons of the year on paniculate
values.
Variables measured during the mine
visits included dust concentrations, soil
moisture, quantitative data on the
pattern and intensity of mining activ-
ities, and meteorological variables such
as wind speed and direction, tempera-
ture, and precipitation. Aerial
photographs were taken from which
maps were drawn.
Several factors must be considered in
the design of a sampling plan for
measuring the atmospheric concentra-
tion of particulates. Some of these are:
1. Emissions sources to be measured.
2. Direction of the air sampler from
the source.
3. Distance of the air sampler from the
source.
4. Duration of sampling interval.
The goal is to place the monitors in
such a manner that a profile of the
concentration of particulates can be
obtained. Sampler locations and
sampling intervals are such that suffi-
cient amounts of particulates will be
collected to give reliable estimates of
the air concentration at the receptor
point. We first considered sampling
intervals.
Dust concentrations were measured
with General Metal Works GMWL 2000
high volume air samplers. These draw
in paniculate matter and pass them
through a graded series of paper filters.
At the end of each observation period,
the filters were removed and weighed,
and the accumulated dust was con-
verted to a concentration in units of
micrograms per cubic meter.
Soil moisture as percent of total
weight was recorded at locations
designed to reflect diverse soil condi-
tions: haul roads, the pit and bench, off-
mine roads, topsoil or spoil piles, areas
of contouring or reclamation, and the
surrounding landscape.
Mining activities were recorded
during shifts when dust sampling was
active. Twelve potential dust-producing
activities were observed: dragline oper-
ation, coal haulage, vehicular traffic on
mine roads, vehicular traffic on nearby
public roads (usually unpaved), water
2
trucks, scraping, grading, coal loading,
coal unloading, blasting, and drilling of
overburden and coal.
The report summarizes the results of
various statistical analyses of the data
collected as part of this study. It judges
differences in paniculate values
measured at various locations, mines,
and seasons that can be held to be
statistically significant. Estimates of
main and interaction effects and
complete components of variance
analysis are furnished in the report. The
report presents the findings of differ-
ences among samplers such as
differences arising between the
ambient sampler and those downwind
of the mining operation. Shown also is
the relationship between particulates
and activity variables at the mining
operations visited.
Reported,in particular.are the results
of preliminary statistical analysis of the
data and analysis of variance (ANOVA)
on total particulates. The results of the
analysis of variance support the
contention that there were significant
differences in readings among sampler
locations.
Also discussed are some of the
results of regression analysis to
determine the relationship between
observed TSP and activity levels for
various mining operations.
The independent variables consisted
of observations on some twelve activ-
ities at the mine operation, including
dragline operation, coal haulage,
drilling, blasting, loading, scraping,
grading, etc. Additionally, wind speed
and precipitation were employed in
view of their observed or postulated
relationships in previous analyses. The
first observation of interest in examin-
ing the relationship between mine
activity and resulting TSP values is the
pattern of simple correlation coeffici-
ents. Two points are worthy of note: the
exception of variable Cb (on-mine
vehicles) TSP is positively correlated
with each of the activity variables and
the correlation coefficients are not
great.
Frank Cook, Arlo Hendrikson, L. Daniel Maxim, and Paul R. Saunders are with
Mathematica, Inc., Princeton, NJ 08540
Edward R. Bates is the EPA Project Officer (see below)
The complete report, entitled "Fugitive Dust from Western Surface Coal Mines,"
(Order No. PB 80 221955; Cost: $15.00, subject to change) will be available
from:
National Technical Information Service
5285 Port Royal Road
Springfield. VA 22161
Telephone: 703-487-4650
The EPA Project Office can be contacted at:
Industrial Environmental Research Laboratory
U.S. Environmental Protection Agency
Cincinnati, OH 45268
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