&EPA
United States
Environmental Protection
Agency
Environmental Monitoring
Systems Laboratory
P.O. Box 15027
Las Vegas NV89114
EPA-600/7-80-110
June 1980
Research and Development
Groundwater Quality
Monitoring of Western
Coal Strip Mining:
Preliminary Designs
for Active Mine
Sources of Pollution
Interagency Energy-
Environment Research
and Development
Program Report
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RESEARCH REPORTING SERIES
Research reports of the Office of Research and Development, U.S. Environmental
Protection Agency, have been grouped into nine series. These nine broad categories
were established to facilitate further development and application of environmental
technology. Elimination of traditional grouping was consciously planned to foster
technology transfer and a maximum interface in related fields. The nine series are;
1. Environmental Health Effects Research
2. Environmental Protection Technology
3. Ecological Research
4. Environmental Monitoring
5. Socioeconomic Environmental Studies
6. Scientific and Technical Assessment Reports (STAR)
7. Interagency Energy-Environment Research and Development
8. "Special" Reports
9. Miscellaneous Reports
This report has been assigned to the INTERAGENCY ENERGY—ENVIRONMENT
RESEARCH AND DEVELOPMENT series. Reports in this series result from the effort
funded under the 17-agency Federal Energy/Environment Research and Development
Program. These studies relate to EPA'S mission to protect the public health and welfare
from adverse effects of pollutants associated with energy systems. The goal of the Pro-
gram is to assure the rapid development of domestic energy supplies in an environ-
mentally-compatible manner by providing the necessary environmental data and
control technology. Investigations include analyses of the transport of energy-related
pollutants and their health and ecological effects; assessments of, and development of,
control technologies for energy systems; and integrated assessments of a wide range
of energy-related environmental issues.
This document is available to the public through the National Technical Information
Service, Springfield, Virginia 22161
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EPA-600/7-80-110
June 1980
GROUIMDWATER QUALITY MONITORING
OF WESTERN COAL STRIP MINING:
Preliminary Designs for Active
Mine Sources of Pollution
Edited by
Lome G. Everett
Edward W. Hoylman
General Electric Company—TEMPO
Center for Advanced Studies
Santa Barbara, California 93102
Contract No. 68-03-2449
Project Officer
Leslie G. McMillion
Advanced Monitoring Systems Division
Environmental Monitoring Systems Laboratory
Las Vegas, Nevada 89114
ENVIRONMENTAL MONITORING SYSTEMS LABORATORY
OFFICE OF RESEARCH AND DEVELOPMENT
U.S. ENVIRONMENTAL PROTECTION AGENCY
LAS VEGAS, NEVADA 89114
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DISCLAIMER
This report has been reviewed by the Environmental Monitoring Systems
Laboratory—Las Vegas, U.S. Environmental Protection Agency, and approved for
publication. Approval does not signify that the contents necessarily reflect
the views and policies of the U.S. Environmental Protection Agency, nor does
mention of trade names or commercial products constitute endorsement or
recommendation for use.
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FOREWORD
Protection of the environment requires effective regulatory actions
based on sound technical and scientific data. The data must include the
quantitative description and linking of pollutant sources, transport
mechanisms, interactions, and resulting effects on man and his environment.
Because of the complexities involved, assessment of exposure to specific
pollutants in the environment requires a total systems approach that
transcends the media of air, water, and land. The Environmental Monitoring
Systems Laboratory at Las Vegas contributes to the formation and enhancement
of a sound monitoring-data base for exposure assessment through programs
designed to:
• develop and optimize systems and strategies for moni-
toring pollutants and their impact on the environment
• demonstrate new monitoring systems and technologies
by applying them to fulfill special monitoring needs
of the Agency's operating programs
This report presents the second phase of a study to design and verify
groundwater quality monitoring programs for Western coal strip mining. The
development of a groundwater quality monitoring design for potential pollution
sources and the pollutants associated with active mine sources is presented.
A second report covering groundwater quality monitoring designs for reclaimed
mine sources is under preparation. The results of this report will lead to a
field data verification effort. It is anticipated that the verification
program will result in modification to this initial monitoring design. The
research program, of which this report is part, is intended to provide basic
technical information and a planning format for the design of groundwater
quality monitoring programs for Western coal strip mine operations. As such,
the study results may be used by coal developers and their consultants, as
well as the various local, State, and Federal agencies with responsibilities
in environmental monitoring and planning.
Further information on this study and the subject of groundwater quality
monitoring in general can be obtained by contacting the Advanced Monitoring
Systems Division, Environmental Monitoring Systems Laboratory, U.S. Environ-
mental Protection Agency, Las Vegas, Nevada.
Glenn E. Schweitzer
Director
Environmental Monitoring Systems Laboratory
Las Vegas, Nevada
n i
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PREFACE
General Electrio-TEMPO, Center for Advanced Studies, is conducting a
5-year program dealing with the design and verification of an exemplary
groundwater quality monitoring program for Western coal strip mining. The
coal strip mining activity discussed in this report is located in Campbell
County, Wyoming. In addition to active mine sources and reclaimed mine
sources, the investigation covers secondary water resource impacts of muni-
cipal and industrial support programs which accompany the mining effort. The
report follows a stepwise monitoring methodology developed by TEMPO.
The report represents the second phase of this research program. De-
scribed herein is the initial design of a groundwater qua!ity monitoring
program for potential pollution sources and pollutants associated with active
mine operations.
In the next phases of this research program, the preliminary monitoring
designs are to be verified with available data. Initial verification study
results may produce a reevaluation of the monitoring design presented in this
report. The final product of the 5-year program will be a planning document
which will provide a technical basis and a methodology for the design of
groundwater quality monitoring programs for coal development companies and
the various governmental agencies concerned with environmental planning and
protection.
IV
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SUMMARY
Preliminary groundwater quality monitoring designs for coal strip mine
stockpiles, mine water sources, and miscellaneous mine sources are developed
in this report and summarized in Appendix B, Tables B-l, B-2, and B-3, re-
spectively. Preliminary monitoring steps identifying potential pollutants
are presented for each source. Subsequent monitoring steps based upon the
TEMPO groundwater quality monitoring methodology are given for a representa-
tive source material in the stockpile and mine water source categories but
are not given for miscellaneous sources. This is done to reduce unnecessary
repetition. For example, potential pollutants for mine stockpiles, i.e.,
topsoil, overburden, and coal, coal refuse and coaly waste, are given. Fur-
ther monitoring steps refer to topsoil source material, but are representa-
tive of the methodology utilized for overburden, coal, coal refuse, and coaly
waste sources. A similar format is used for the active mine water sources.
Miscellaneous sources include both solid and liquid materials and appropriate
methods for groundwater quality monitor design can be found under stockpile
or mine water sources.
Unit cost estimates for the monitoring designs, based on preliminary
recommendations, are given in Appendix B, Tables B-l, B-2, and B-3. In de-
veloping these estimates, each monitoring step was considered separately and,
therefore, some overlap in the capital costs occurs in these figures. For
example, only one hand-driven soil sampler would be required to monitor top-
soil, overburden, and coaly waste stockpiles. This overlap would not occur
when capital costs were developed for a specific monitoring design. In addi-
tion, each major cost item (i.e., monitor well) would be installed in response
to a perceived pollution threat and would not be developed simply to measure
background levels. The assignment of major cost items to a particular mon-
itoring step may, in the generic case, be somewhat arbitrary. Take, for
example, a monitor well installed near a sedimentation pond as part of the
hydrogeologic framework monitoring step. Before this well would be drilled,
previous iterations through the monitoring design would have indicated that
a significant amount of potential pollutants was infiltrating into and mi-
grating through the vadose zone near the source area. With this information,
monitor well(s) would be installed near the source area using data on the
local flow patterns developed as part of the hydrogeologic framework. Alter-
natively, the costs of the well might have been attributed to mobility in the
saturated zone, a subsequent monitoring step; however, the total cost to the
monitoring program would remain unchanged.
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CONTENTS
Foreword iii
Preface iv
Summary v
Figures viii
Tables viii
List of Abbreviations, Chemical Elements and Compounds ix
Acknowledgments xi
Section
1 Monitoring Program Development 1
Introduction 1
Summary of Preliminary Monitoring Designs 3
2 Monitoring Design for Mine Stockpiles 4
General Case Considerations 4
Example Case Study—AMAX Belle Ayr South 17
3 Monitoring Design for Mine Water Sources 28
General Case Considerations 28
Example Case Study—Sun Oil Company's Cordero Mine 56
4 Monitoring Design for Miscellaneous Active Mine Sources 63
General Case Considerations 63
References 82
Appendices
A Metric Conversion Table 85
B Summary of Preliminary Monitoring Designs 87
vn
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FIGURES
Number
1
2
4
5
6
AMAX Belle Ayr South topsoil stockpile location.
Water-Analysis diagram, Belle Ayr South Wasatch Formation,
N-5 and scoria pit (SP) wells.
Water-analysis diagram, Belle Ayr South Wyodak coal mean
values.
Multilevel groundwater sampler.
Groundwater profile sampler.
Location of sedimentation pond.
Page
18
25
26
54
55
57
TABLES
Number Page
1 Chemical Analysis for Overburden Stockpiles 7
2 AMAX Belle Ayr Water Quality—Wasatch Formation Above
the Coal 21
3 AMAX Belle Ayr Water Quality Data—Scoria Pit—Wasatch
Formation above the Coal 22
4 AMAX Belle Ayr Water Quality Data—Wyodak Coal 23
5 AMAX Belle Ayr Water Quality Data—Fort Union Formation
Below Coal 24
6 Groundwater Quality, Hayden Residence, Sun Oil Cordero Lease 60
7 Groundwater Quality, Well Number 11, Sun Oil Cordero Lease 61
B-l Summary of Preliminary Monitoring Design for Topsoil
Stockpiles, for Overburden Stockpiles, and for Coal, Coal
Refuse and Coaly Waste Stockpiles 88
B-2 Preliminary Monitoring Design—Mine Water Sources 93
B-3 Summary of Preliminary Monitoring Design for Miscellaneous
Active Mine Sources 100
VI 1 1
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LIST OF ABBREVIATIONS, CHEMICAL ELEMENTS
AND COMPOUNDS
ABBREVIATIONS
ANFO
BOD
Btu
cm
COD
DEQ
DMA
DO
DOC
DPTA
EC
Eh
EPA
epm
9
gpd
gpm
JTU (turbidity)
m
m3
MB AS
mg
MLSS
NPDES
ppm
PVC
SAR
SCS
SV solids
TDS
TK
TOC
TSS
ammonium-nitrate—fuel oil
biochemical oxygen demand
British thermal units
centimeters
chemical oxygen demand
Department of Environmental Quality
designated monitoring agency
dissolved oxygen
dissolved organic carbon
diethylenetriamine pentaacetic acid
electrical conductivity
oxidation reduction
U.S. Environmental Protection Agency
equivalents per million
grams
gallons per day
gal Ions per minute
Jackson turbidity units
meters
cubic meters
methylene blue active substances
milligrams
mixed liquor suspended solids
National Pollution Discharge Elimination System
parts per million
polyvinyl chloride
sodium adsorption ratio
Soil Conservation Service
suspended volatile solids
total dissolved solids
total Kjeldahl
total organic carbon
total suspended solids
yg
ymhos
micrograms
micromhos
IX
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CHEMICAL ELEMENTS AND COMPOUNDS
Ag
As
B
Be
C
Ca
Cd
CdS
Cl
Co
co2
co3
Cr
Cu
CuS
F
Fe
FeS
Ge
H
HC10
HC0
Hg
Hg2S
HgS
HN03
K
silver Mg
arsenic Mn
boron Mo
beryllium N
carbon Na
calcium NaCl
calcium sulfate NH3-N
cadmium NH$
cadmium sulfide Ni
chlorine N03
cobalt N02
carbon dioxide N02-N
carbon trioxide N03-N
chromium NO
A
copper 0
cuprous sulfide P
fluorine Pb
iron PbS
ferrous sulfide PO.
germanium Ru
hydrogen S
perchloric acid Se
bicarbonate SiO?
orthophosphoric acid SO-
sulfuric acid SO.
mercury Th
mercurous sulfide U
mercuric sulfide V
nitric acid Zn
potassium ZnS
potassium dichromate
magnesium
manganese
molybdenum
nitrogen
sodium
sodium chloride
ammonium-nitrogen
ammonium
nickel
nitrate
nitrogen dioxide
nitrite-nitrogen
nitrate-nitrogen
mixed nitrogen oxides
oxygen
phosphorus
lead
lead sulfide
phosphate
ruthenium
sulfur
selenium
silica dioxide
sulfur dioxide
sulfate
thorium
uranium
vanadium
zinc
zinc sulfide
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ACKNOWLEDGMENTS
Dr. Lome G. Everett of General Electrio-TEMPO was responsible for man-
agement and technical guidance of the project under which this report was
prepared. Mr. Edward W. Hoylman was responsible for the organization and
presentation of the report. Principal TEMPO authors were:
Dr. Lome G. Everett
Mr. Edward W. Hoylman
Dr. Guenton C. Slawson, Jr.
Principal consultant authors were:
Dr. S.N. Davis, University of Arizona, Tucson, Arizona
Ms. Margery A. Hulburt, Department of Environmental Quality, State
of Wyoming, Cheyenne, Wyoming
Mr. Louis Meschede, University of Arizona, Tucson, Arizona
Dr. Roger Peebles, University of Arizona, Tucson, Arizona
Dr. Kenneth D. Schmidt, Consultant, Fresno, California
Dr. John L. Thames, University of Arizona, Tucson, Arizona
Dr. Richard M. Tinlin, Consultant, Camp Verde, Arizona
Dr. David K. Todd, University of California, Berkeley, California
Dr. Donald L. Warner, University of Missouri, Rolla, Missouri
Dr. L. Graham Wilson, University of Arizona, Tucson, Arizona.
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SECTION 1
MONITORING PROGRAM DEVELOPMENT
INTRODUCTION
This report is the third in a series dealing with development of guide-
lines for the design of groundwater quality monitoring programs for Western
coal strip mining. The initial report (Everett, 1979) dealt with the identi-
fication of potential sources of groundwater quality impact; characteristics
of potential pollutants; source area hydrogeology and groundwater quality;
and infiltration and mobility of pollutants in the subsurface. These assess-
ments, which focused on a case study region around Gillette, Wyoming, resulted
in a preliminary priority ranking of pollution sources in three categories:
municipal, active mining, and reclaimed mine areas. Separate preliminary
monitoring design reports have been developed for each of these categories.
Prel iminary monitoring designs for active mine sources are presented in
the following sections of this report. The term "design" is used in a broad
sense here to mean a structured sequence of data gathering, evaluation, and
decision steps which result in a determination of what monitoring activities
are needed and what are the appropriate methods for addressing these needs.
Potential sources of groundwater quality impact associated with active
mining have been grouped as follows for consideration in this report:
• Stockpiles (topsoil, overburden, coal, coal refuse, and coaly
waste)
• Mine water (sedimentation ponds and pit water)
• Miscellaneous sources (explosives, mine solid wastes, liquid
shop wastes, sanitary wastes, spills and leaks, and solid waste
for road construction).
Ranking of pollution sources for coal strip mines is given in the first
report in this series (Everett, 1979). This ranking is based on a sequence
of data compilation and evaluation steps. These steps include identification
of potential pollution sources given above, methods of waste disposal and
potential pollutants associated with the various waste sources, and an assess-
ment of the potential for infiltration and subsequent mobility of these pol-
lutants in the subsurface. The three basic criteria used to develop the
source-pollutant ranking are:
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• Mass of waste, persistence, toxicity, and concentration
• Potential mobility
• Known or anticipated harm to water use.
A great deal of effort has been expended on the study of the hydrogeology
of mine areas and a large amount of research has been conducted on coal strip
mine development and environmental effects. However, significant information
deficiencies exist with regard to potential pollutant characterization and
the mobility of these materials in the hydrosphere. Hence, professional
judgment plays a large role in proposing this preliminary source-pollutant
ranking which is as follows (from Everett, 1979):
1. Spoils (below water table)
2. Spoils (above water table below ponds or streams)
3. Pit discharge (to streams).
Of these ranked pollution sources, pit discharge is covered in Section 3
of this report. Backfilled spoils, above and below the water table, will be
covered in a subsequent report. Other sources discussed herein may have less
impact on groundwater quality than those given in Appendix B, Table B-l.
The format for presenting these preliminary designs follows the generic
monitoring methodology developed by General Electric Company—TEMPO (Todd
et al., 1976):
• Identify potential pollutants
• Define groundwater usage
• Define hydrogeologic situation
• Study existing groundwater quality
• Evaluate infiltration potential
• Evaluate mobility in the vadose zone
• Evaluate attenuation of pollutants in the saturated zone.
For each of.these information assessment steps, one must consider monitoring
(information) needs and alternative approaches for addressing these needs.
These basically technical assessments, along with cost data, result in selec-
tion of a monitoring approach. It is important to note that each step in
this design sequence is a decision point: if for a given source the data and
evaluations, at some point, indicate the absence of appreciable potential for
impact to groundwater quality then this conclusion is the end product of the
monitoring design. Additionally, conclusions at one step will refocus
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efforts for subsequent steps. Multiple passes through the methodology steps,
with successive passes dealing with more detailed data sets and generally
higher costs for developing required information, are employed to "scale-up"
to an appropriate and cost-effective level of monitoring effort.
Thus, at specific sites, different monitoring designs may result for any
of the potential pollution sources considered in this report. In order to
address the general guideline goals of this study, the preliminary designs
presented herein follow the above-outlined sequence of steps entirely through,
and a monitoring approach is "selected." Given the decision-tree approach
outlined above and only regional specificity, the designs thus developed must
be considered in some respects generic. To balance this factor, certain
example cases taken from coal strip mines near Gillette, Wyoming, are pre-
sented as part of this report.
SUMMARY OF PRELIMINARY MONITORING DESIGNS
Although the Permanent Regulatory Program for the U.S. Department of the
Interior Surface Mining Control and Reclamation Act of 1977 was published in
the Federal Register on 3-13-79, the U.S. Environmental Protection Agency
(EPA) did not change the scope of the project to specifically cover this new
legislation from the U.S. Department of the Interior. Technical reviews of
the monitoring design, however, have been made by the Office of Surface
Mining.
Specific sections of the Surface Mining Act deal with protection of the
hydrologic system. In general, the provisions state that operations will be
conducted so as to minimize water pollution. For example, practices to con-
trol and minimize pollution include diverting runoff. Overland flow may be
diverted and conveyed away from disturbed areas. All surface drainage from
the disturbed areas shall be passed through one or more sedimentation ponds
before leaving the permit area.
Discharge, on the other hand, from areas disturbed by surface coal min-
ing and reclamation operations must meet all applicable Federal and State
laws and regulations. Specific numerical limitations have been established
for iron, manganese, total suspended solids (TSS), and pH. In general, regu-
lations require that a surface water monitoring program shall be conducted
that provides adequate monitoring of all discharges from the disturbed area.
This report deals with detailed preliminary guidelines that may elabor-
ate upon existing Federal and State regulations for groundwater quality moni-
toring of active coal mine sources.
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SECTION 2
MONITORING DESIGN FOR MINE STOCKPILES
GENERAL CASE CONSIDERATIONS
Three categories of materials may be stockpiled at a coal strip mine:
(1) topsoil, (2) overburden and interburden, and (3) coal, coal refuse, and
coaly waste, discussed in more detail in Everett (1979).
The three types of stockpiles may yield different potential pollutants
to the groundwater beneath them; therefore, the identification of potential
pollutants is discussed separately fx>r each material. The remaining steps
are discussed for stockpiles in general.
Identify Potential Po11utants--Topsoi1
The purpose of potential pollutant identification at the beginning of
the monitoring program is to specify pollutants which should be monitored
during subsequent steps of the methodology.
Potential groundwater pollutants in stockpiled topsoil may be due to
(1) the natural poor quality of soils that are stockpiled, (2) fertilization
and irrigation of the stockpiled soils, and (3) physical and chemical changes
in the soils after they have been stockpiled for long periods of time. Poor
quality soils may be treated as spoils or may be stockpiled with topsoil.
If vegetation is not immediately established on topsoil stockpiles, they
will contribute excessive sediment to sedimentation ponds. However, if the
stockpiles are fertilized and irrigated, it is possible that leaching could
occur by waters percolating through the root zone. Compounds of nitrogen,
phosphorus, and potassium could be potential pollutants, nitrates being of
principal concern.
Gradual physical and chemical changes that may occur in stockpiles of
long duration will primarily be due to leaching in the surface layer. It is
expected that there may be leaching of nitrates and other readily soluble
salts turned over from lower soil layers by the mixing that will occur during
stockpiling operations. If the stockpiles are deep, microorganisms will be
diminished at the lower levels, particularly in the soils underlying the
stockpiles. Accordingly, an increase in ammonium-nitrate could be expected
in the deeper layers.
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Monitoring Needs--
Monitoring needs include identification and characterization of soils on
the lease area, estimations of the locations, volumes and anticipated dura-
tion of topsoil stockpiles, and characterization of physical and chemical
changes in soils which have been stockpiled for extended periods of time.
Alternative Monitoring Approaches--
In many cases, a nonsampling approach is preferable to sampling. Gener-
ally, nonsampling methods involve collecting and examining pollutant-related
information for a potential pollution source, such as number of stockpiles,
collection of available soil chemistry data, etc. The results of nonsampling
methods may indicate that further monitoring activities are unwarranted.
Possible alternative nonsampling and sampling approaches for identifying
potential pollutants due to stockpiled topsoil are given below.
Soil inventory maps could be obtained and used to identify soils that
may be stockpiled and their chemical characteristics. Plans for removal of
topsoil could be compared with soil inventory maps for a closer estimate of
future stockpile material. The plans could be used to estimate the volume of
topsoil to be stockpiled and the expected life of individual stockpiles.
The volume of existing stockpiles could be estimated in three ways:
(1) the stockpiles could be measured and the volumes computed, (2) aerial
photography could be used to estimate the volume of stockpiles, and (3) the
volume could be estimated from mine engineering and production records and
mine plans. The documents could also yield information on the use of irriga-
tion and fertilizers on stockpiles.
The volume of potential pollutants in the stockpiles could be estimated
from the volume of the stockpiled material and information on potential pol-
lutants in the topsoil.
Stockpiles which have been in place for a year or more could be sampled
to assess physical and chemical changes occurring over time. Samples could
be collected at 2-foot* intervals at no less than one point per acre of stock-
piled material. They could be analyzed for pH (determination on paste), con-
ductivity (mmhos/cm on saturated extract), saturation percentage9 calcium,
magnesium, sodium, sodium adsorption ratio (SAR), boron (hot water extract),
nitrogen (sum of nitrate-nitrogen and ammonium-nitrogen in soil), phosphorus,
potassium, trace metals, and total salts. Sampling could be performed
annually.
Preliminary Recommendations--
The preferred monitoring approach would be to obtain soil inventory
maps, topsoil removal and storage plans, mine engineering and production
records, and mine plans. These would be used, together with existing soil
* See Appendix A for conversion to metric units.
5
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chemistry information, to identify the locations and quantities of potential
pollutants in topsoil stockpiles. Stockpiles which have been in place for a
year or more would be sampled as described above. The use of aerial photog-
raphy would not be recommended for mines with small numbers of closely spaced
stockpiles due to the expense of utilizing this method.
Costs for this monitoring approach would include labor for gathering
existing information and sampling operation costs for sampling equipment and
analyses. These costs are itemized in Appendix B, Table B-l.
Identify Potential Pollutants—Overburden and Interburden
The primary potential pollutants in the overburden are soluble salts.
In addition, iron sulfide minerals and trace elements present in the overbur-
den are of concern as possible sources of groundwater pollutants.
Monitoring Needs--
Data related to overburden materials in place may be useful in charac-
terizing overburden stockpiles; however, it will also be necessary to monitor
stockpiled overburden materials to determine if any appreciable changes in
their overall composition have resulted from mining and stockpiling of the
materials. Monitoring needs include: the chemical composition of in-place
overburden; the volume, composition, and expected life of overburden stock-
piles; and changes which take place in the overall chemical makeup of stock-
piled overburden due to exposure to a new environment.
Alternative Monitoring Approaches—
A primary nonsampling approach could be to obtain, review, and interpret
existing data on the chemical characteristics of the in-place overburden.
The volume of overburden stockpiled for any appreciable time (1 year or more)
could be estimated using any of the techniques discussed for topsoil stock-
piles. The information gathered above could then be used to estimate the
volume and chemical nature of potential pollutants in the stockpiled
overburden.
Overburden samples expected to remain in place for a year or more could
be sampled to determine if any changes are taking place in their chemical
makeup. A rule of thumb would be to obtain samples at 10-foot intervals ver-
tically through the stockpile (Wyoming Department of Environmental Quality,
1978). A minimum of two samples (a surface sample and one near the base)
could be obtained from each stockpile sampling location regardless of total
vertical depth of the stockpiled material. One sample hole per 10 acres of
surface area should be sufficient. All samples could be analyzed for the
quantities listed in Table 1.
Prelimi nary Recommendati ons--
The preferred approach for monitoring the potential pollutants in stock-
piled overburden would be as follows:
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TABLE 1. CHEMICAL ANALYSIS FOR OVERBURDEN STOCKPILES
Quantity
Method of analyses
Suspect level
pH
Conductivity
SAR
Texture
Boron
Cadmium
Copper
Iron
Paste
Saturation extract
Saturation extract
Hydrometer
Hot water extract
DTPA extract
DTPA extract
DTPA extract
8.8-9.0
4-6
12
40% clay, loamy
sand and sand
8 ppm
0.1-1 ppm
40 ppm
not defined
Lead
Manganese
Mercury
Molybdenum
Nickel
Selenium
Zinc
Ammonium-nitrogen
Nitrate-nitrogen
DTPA extract
DTPA extract
Cone, acid extract
Acid ammonium oxalate
DTPA extract
Hot water extract
DTPA extract
NaCl solute extraction
NaCl solute extraction
or CaS04 NaCl solute
extraction
pH <6 (10-15)
pH >6 (15-20)
60 ppm
400-600 ppb
0,3 ppin
1.0 ppm
2.0 ppm
40 ppm
(a)
(a)
The significance of ammonium and nitrate stems from the water
pollution potential of nitrate. The Federal drinking water
standard is 10 ppm nitrate-nitrogen and a recommended maximum
concentration for livestock is 100 ppm nitrite + nitrate-
nitrogen. Ammonium can be biologically oxidized to nitrate
if conditions are suitable.
Note: The quantities and their suspect levels listed above are
those established by the Montana Coal and Uranium Bureau, Depart-
ment of State Lands, 1978. A comparison with Wyoming standards
can be found in Wyoming Department of Environmental Quality,
1978.
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1. Review existing data on chemistry of in-place overburden
2. Determine the volume of overburden stockpiled by direct meas-
urement
3. Sample the stockpile at 10-foot intervals; a minimum of two
samples per location, with one hole every 10 acres
4. Analyze annually for parameters listed in Table 1; although
leaching tests would be of value, they are too costly to be
used routinely in a monitoring program.
Costs would include labor for gathering existing information and sam-
pling and operational costs for sampling equipment and analyses. These costs
are itemized in Appendix B, Table B-l.
Identify Potential Pollutants—Coal, Coal Refuse, and Coaly Waste
Coal, coal refuse, and coaly waste are considered together since they
are geologically and chemically similar. Coal refuse is defined as the fine
coal and waste material removed during the coal preparation process. Coaly
waste includes the thin coal seams, impure coal, and carbonaceous shale that
may occur in the overburden and within the partings between coal seams.
These materials are handled separately because of their economic value and
different water pollution potentials.
Coal is mined soon after exposure by stripping and is not allowed to
weather or to have much water percolate through it to pick up pollutants cre-
ated by the oxidation process. After mining, it will usually be processed in
some manner. Common steps in coal processing include crushing, screening,
and washing. Coal at Powder River Basin mines is usually only crushed. At
the Wyodak Mine, it is crushed and part of it is sized and oiled for sale to
the domestic market. So far as is known, no coal waste is produced during
the preparation at mines within the project area. All of the coal, including
the finest portion, is used. After crushing, coal is temporarily stored in
silos, bunkers, or occasionally in open piles.
When coal refuse is produced during preparation, as is common with coal
from other geographic areas, it is disposed of in refuse piles (large size
material) and ponds (fine material carried as a slurry). Apparently, coal
refuse will not exist at Powder River Basin mines.
Coaly waste material is considered separately from overburden because it
usually has a different type and amount of water pollution potential. The
geochemical properties of coaly waste materials affect its potential as a
soil-forming material. Such materials commonly form toxic soils and are thus
segregated from overburden during mining. A frequent method of handling is
to attempt to place the coaly waste at or near the bottom of the spoil. In
order to place the coaly waste selectively, it may be necessary to stockpile
it temporarily.
-------
Coal, coal refuse, and coaly waste probably contain some soluble salts,
although no analysis of the soluble salt content of these materials has been
found in the literature. The soluble salts are expected to be principally in
the form of crystals of gypsum or similar minerals formed in open fractures.
One of the characteristics of the project area coals is the low sulfur
content. However, some pyrite oxidation does occur, as is evidenced by spon-
taneous combustion of coal piles along the base of the high wall at the Wyodak
Mine. Apparently, the acid that does form from oxidation of pyrite in Powder
River Basin coal and associated carbonaceous strata is rapidly neutralized,
probably by carbonate minerals in the soil and overburden, and does not cause
measurable lowering of the pH of surface water and groundwater. It will,
however, contribute dissolved solids in the form of sulfate, principally cal-
cium and magnesium. The acid that is found might also dissolve some trace
metals before it is neutralized.
Monitoring Needs—
All mining companies perform sample analyses of coal seams before min-
ing. Usually, the proximate analyses include moisture content, volatile mat-
ter, fixed carbon, ash, Btu, softening, grindability, and specific gravity.
The ultimate analyses may also include H, C, N, 0, S, Cl, sulfate, pyrite,
and organic content. Measurements have also been made of trace elements in
Powder River Basin coals.
Sufficient information is available to characterize coals in the project
area in terms of the potential pollutants they contain, with the exception of
soluble salts. This does not appear to be the case for coaly waste. No rec-
ords have been found to indicate that any attempts have been made to charac-
terize coaly wastes. In order to characterize stockpiled coals in terms of
their pollution potential, stockpiles should be sampled to determine if, in
fact, soluble salts are present in sufficient amounts to present a problem.
Uncertainty exists about the location of coaly waste stockpiles and
methods of disposal for this material on all mining sites. In most instances,
it is mixed indiscriminately with overburden materials and backfilled. Any
existing stockpiles of coaly waste need to be located in order to acquire
grab samples for chemical analysis. This characterization of the coaly wastes
will provide an identification of any potential groundwater pollutants.
Alternative Monitoring Approaches--
A primary nonsampling method for monitoring potential pollutants is to
determine the volume of coal and coaly wastes stockpiled. The manner in
which these materials are stockpiled will, to a large degree, determine if
they present a threat to groundwater quality. For example, coal stored in
open bunkers with concrete floors may not present a problem. The two al-
ternatives for estimating the volume of these materials are: (1) directly
measure the areal extent of the stockpiles and periodically update this in-
formation, or (2) work directly from mine engineering and production reports.
Any available data on the chemical characteristics of the stockpiled materials
-------
could be obtained from the mine operators and used to estimate the total vol-
ume of potential pollutants in the stockpiles.
If the stockpiles are exposed to the elements, some weathering and pos-
sible leaching may take place. Most of the weathering will take place at or
near the surface of the stockpiles. Grab samples could be taken at a few
locations on the stockpiles. These samples could be analyzed for the
following:
Ag
Cu
Ni
Pb
Cd
Zn
Se
Mn
Cr
Hg
B
Be
As
Ge
V
Mo
U
F
The analyses for these elements should be accomplished with an accuracy of
±20 percent of the actual population concentrations. Therefore, at least
three replicates would be necessary for each stockpile. More may be required
to achieve an acceptable error..
Spark-source mass spectrometry is recommended as the most accurate
method. The analyses should include all identifiable trace elements, al-
though only those listed would require an accuracy of ±20 percent.
Other methods, such as neutron activation analyses, may also be used.
However, wet chemical methods are satisfactory and are used by most labora-
tories. Analyses by wet chemical methods should be performed as follows:
Ag - atomic absorption spectrometry
Cu - atomic absorption spectrometry
. Ni - atomic absorption spectrometry
Pb - atomic absorption spectrometry
Cd - atomic absorption spectrometry
Zn - atomic absorption spectrometry
Se - atomic absorption spectrometry
Mn - atomic absorption spectrometry
Cr - atomic absorption spectrometry
Hg - double gold amalgam flameless atomic absorption
B - emission spectrometry
Be - emission spectrometry
10
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As - colorimetric
Ge - colorimetric
V - colorimetric
Mo - colorimetric
U - fluorometric
F - specific ion electrode.
Additional analyses could include H, C, N, 0, S, Cl, $04, and FeS2.
Additional measurements should be adequate to follow any changes in the
chemical characteristics of stockpiled coal, coal refuse, or coaly wastes.
It will be unusual for coal to be stockpiled for such long periods of time.
Frequently, the stockpiles will be added to or taken away from on a regular
basis.
Preliminary Recommendations--
The preferred monitoring approach is to determine the volume of stock-
piled materials by direct measurement and use this information, along with
available data on the chemical characteristics of the stockpiled materials,
to estimate the volume of potential pollutants in the stockpiles. Samples
would be collected and analyzed as needed to fill data gaps.
Costs would include labor for volume measurements, sample collection,
and review of existing data. The major operational cost would be for sample
analysis. Specific costs are itemized in Appendix B, Table B-l.
Define Groundater Usage
Ultimately, source-related pollutants may deleteriously affect various
groundwater uses (municipal, agricultural, and industrial) if recharge from
the source occurs. An inventory of such uses, including the volume of usage
and location of pumping centers, is an integral component of a monitoring
design.
Pumpage of groundwater for domestic use from shallow wells in the vi-
cinity of stockpiled materials is apparently nonexistent. Almost all water
used for domestic purposes is pumped from the deeper Fort Union or Fox Hills
aquifers.
Most of the groundwater used on the mine leases comes from pit dis-
charge. Dust suppression is the primary use of pit discharge water during
summer months. Deep wells supply water for drinking, bathing, and cleanup
(equipment, shops, etc.). Potable water consumption varies depending on mine
equipment, maintenance, shop house cleaning, and bath house capacity.
11
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Although irrigation is not presently practiced at any of the mines in
the Eastern Powder River Basin, the Federal strip mine regulations are speci-
fic in the requirement of establishing vegetation on topsoil stockpiles. It
is quite likely that irrigation will be necessary later during the first and
second growing seasons to obtain good plant establishment on topsoil stock-
piles. Thus, there may be additional demands on existing wells or new wells
may be required to supply water for irrigation.
Monitoring Needs—•
The primary monitoring need is to determine if the stockpiled materials
are to be irrigated and what their irrigation requirements would be, both in
terms of water quantity and quality.
Alternative Monitoring Approaches—
If stockpiles are irrigated for revegetation, the groundwater applied
should be monitored. Simple irrigation metering devices which cost less than
$50 could be installed in the supply lines. The volume of water needed for
irrigation could be estimated by computing the size of the stockpiled areas,
vegetation consumptive water use, and soil characteristics. Consumptive use
of 1 to 4 acre-feet of water per acre being revegetated is typical for the
area.
Preliminary Recommendations—
The recommended preliminary approach is to determine whether stockpiles
are to be irrigated. No further monitoring should be planned unless irriga-
tion is decided upon. The only cost for this approach would be labor for
discussions with mine personnel. However, labor, operation, and capital
costs for monitoring stockpile irrigation have been summarized in Appendix B,
Table B-l, should this plan be initiated.
Define Hydrogeologic Situation
Evaluation of the hydrogeologic framework of a pollutant source area
includes description of the local and regional geology; identification of
aquifer locations, -interactions, and characteristics; determination of depths
to groundwater and velocities of flow; and delineation of areas and magni-
tudes of natural groundwater recharge and discharge. The hydrogeology should
be clearly understood in a source-specific sense; however, it is of equal
importance that the regional hydrogeology be defined in order to predict the
long-term impact of pollution from a source, including the effect of mixing
of pollutants from several sources. Generally, this information is collected
on a regional basis by the individual mining companies.
Monitoring Needs—
The most important monitoring requirement is collection and analysis of
existing data. These data may then need to be supplemented by additional
monitoring to characterize the site-specific hydrogeology.
12
-------
Alternative Monitoring Approaches--
Available hydrogeological information could be collected from a number
of sources, including the mine operator, private consultants, the U.S. Geo-
logical Survey, State agencies, etc. Types of information which could be
solicited include: well locations, details on well construction (construc-
tion methods, depth, diameter, locations of perforations, completion tech-
niques), drillers logs and geophysical data, and results of pumping tests for
aquifer properties (including test methods). If necessary to complete the
regional hydrogeologic picture, data could also be collected from adjoining
mines.
Pumping tests and water level monitoring could be carried out in exist-
ing wells in the vicinity of stockpiled materials. If necessary, additional
wells could be installed for these purposes.
Preliminary Recommendations—
The preliminary recommended approach is to collect and analyze all
available hydrogeologic data. Plans for further drilling and testing can
then be made on the basis of this information and data gathered from other
monitoring steps. The only costs accrued for this work would be labor to
compile and review existing data. If additional testing or monitoring wells
were required, costs would include labor for well construction, drilling, and
capital costs for well hardware and testing/sampling equipment. Costs for
additional sampling of existing wells are given in Appendix B, Table B-l.
Costs for installing new monitor wells are summarized in Appendix B, Table
B-2.
Study Existing Groundwater Quality
The general purpose of determining groundwater quality in the vicinity
of a potential source of pollution, such as stockpiles, is to characterize
the impact of pollutant movement on the indigenous groundwater quality.
Activities during this step will overlap related steps involving characteriz-
ing the hydrogeologic framework and determining the attenuation of pollutants
in the zone of saturation.
Monitoring Needs--
Monitoring needs include the characterization of the chemical quality of
groundwater both in the vicinity of stockpiled materials and on a regional
basis.
Alternative Monitoring Approaches--
Available water quality data could be obtained and examined. Possible
sources of data include: the mining company, the U.S. Geological Survey,
consultants, etc.
A water sampling program could be initiated to characterize the current
groundwater quality in the vicinity of stockpiled materials. Methods include
13
-------
sampling from existing monitor wells, if such wells are near the stockpiles;
installation of supplemental wells; and a combination of these methods. Sup-
plemental wells may have been constructed, as necessary, during the previous
step (Define Hydrogeologic Situation).
Water samples could be obtained by a variety of alternative techniques,
discussed in the municipal monitoring design report.
Three methods of water sample analysis are possible. All samples could
be completely analyzed for the following constituents: calcium, magnesium,
sodium, potassium, bicarbonate, chloride, sulfate, phosphate, silica, ammonium-
nitrogen, nitrate-nitrogen, total nitrogen, iron, manganese, zinc, copper,
chromium, arsenic, molybdenum, and selenium. Alternatively the first few
samples could be examined completely. Once the principal constituents are
identified (primarily those occurring in greater-than-permissible levels),
subsequent analyses would be for these constituents only. Note that this
approach should be used only for trace constituents. The major constituents
should be determined for each sample. A third technique would be to field
analyze pH, electrical conductivity (EC), dissolved oxygen, alkalinity,
chloride, and nitrate. When pronounced changes (above instrument or experi-
mental error) occur, a sample could be collected for laboratory analyses.
Possible sampling frequencies to characterize groundwater quality in-
clude daily, weekly, semimonthly, monthly, bimonthly, etc. Samples could be
collected on a weekly basis until time trends in quality are established.
Thereafter, samples could be obtained on a bimonthly basis. Note, however,
that unusual events may necessitate a greater sampling frequency.
Preliminary Recommendations--
The recommended preliminary approach is to obtain and examine existing
water quality data. A water sampling program would then be initiated, if
necessary, using existing wells and any wells installed during alternate
steps. The first five samples from each well would be analyzed completely,
and parameters in excess of recommended limits would be delineated. Periodic
field checks would then be conducted for such parameters as pH, EC, dissolved
oxygen, nitrate, and chloride. Samples would be collected for laboratory
analyses when marked changes occur between field checks. Samples would be
analyzed for major constituents and those trace constituents previously found
to be in excess of recommended limits. Sampling frequency would be as de-
scribed above.
Costs for characterizing groundwater quality would include: .labor costs
for examining available water quality data and collecting samples; capital
costs for pumps or bailers, pH, conductivity and dissolved oxygen meters, and
a field kit for determining chloride and nitrate; and operational costs for
sample analyses and miscellaneous items, such as sample bottles, thermome-
ters, chemicals, storage chest, etc. These costs and those incurred during
installation of a monitor well are given in Appendix B, Table B-l.
14
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Infiltration Potential
The purpose of determining the infiltration potential of a source is to
quantify the volume of water and associated pollutants moving into the under-
lying vadose zone. Premining soil surveys classify the hydrology of natural
soils in general categories. However, this classification is of limited
value in evaluating the infiltration characteristics of topsoil stockpiles.
Information on these characteristics will have to be obtained for the stock-
piles themselves.
Monitoring Needs--
There is a need to determine if water could move through the stockpiles
in quantities sufficient to carry potential pollutants into the vadose zone.
Although infiltration from rainfall or snowmelt will be high to moderately
high on the loose materials of stockpiles, it is unlikely that infiltrating
water will penetrate deep enough under the natural precipitation regime or
artificial irrigation to contribute significantly to groundwater. However,
this must be established, particularly for stockpile areas near natural
stream channels or areas where the groundwater is shallow.
Alternative Monitoring Approaches--
Laboratory determinations of saturated conductivity on disturbed samples
are of doubtful value for indicating infiltration characteristics. However,
infiltrometer tests in the field are useful for establishing maximum limits
of water penetration at the soil surface. A simple ring infiltrometer could
be used to perform field tests on the stockpiles. Data could be analyzed to
determine the probable penetration of water under natural rates of precipita-
tion or under applied irrigation schedules. Several methods are available
for determining infiltration under conditions of unsteady application of
water at the surface. These methods could be used with climatic records to
determine maximum expected depth of water penetration.
Preliminary Recommendations--
Simple ring infiltrometer tests would be run as discussed above. No
fewer than three runs would be made on each stockpile, and more would be made
if considerable variation is found to exist in the materials. Costs would
include labor for conducting and analyzing the infiltration tests and capital
costs for infiltrometers. These costs are itemized in Appendix B, Table B-l.
Evaluate Mobility in the Vadose Zone
The general purpose of this step is to measure or estimate the movement
of pollutants in the vadose zone underlying a pollution source.
Monitoring Needs--
Information on the mobility of pollutants in the vadose zone within or
beneath present or future topsoil and overburden stockpiles is not currently
15
-------
available. There is a need to first determine if water is moving in signifi-
cant quantities through the stockpiles. If so, it will be necessary to moni-
tor those pollutants which contribute contaminants in excess of background
levels.
Alternative Monitoring Approaches—
The greatest amount of water movement in the vadose zone will occur as
unsaturated flow. Although the soil surface may become saturated after heavy
rainfall, snowmelt, or prolonged irrigation, subsequent movement will occur
at pressures less than atmospheric along gravitational and soil matrix poten-
tial gradients. One way of monitoring unsaturated flow is through the in-
stallation of neutron probes in the stockpile. These could extend several
feet into the underlying spoils or native soil. Measurements could be made
with the neutron probe or on a monthly basis and more frequently after pre-
cipitation events or extended irrigation.
Tensiometers could be installed to measure pressure differentials with
depth and thereby determine the rate and volume of flow. Tensiometers are
only effective at moisture contents equivalent to negative pressure of less
than 1 bar.
Porous cups installed within the stockpile at the same depths as the
tensiometers could be used to extract the soil solution for analysis of pol-
lutants if the moisture content is sufficiently high. The cups will fail at
-0.8 atmosphere of soil water pressure. Samples could initially be analyzed
for calcium, magnesium, sodium, potassium, bicarbonate, chloride, sulfate,
phosphate, silica, ammonium-nitrogen, nitrate-nitrogen, total nitrogen, pH,
and electrical conductivity. Subsequent monitoring could be limited to the
quantities which appear to be in excess of 20 percent of the previously de-
termined background levels.
Preliminary Recommendations--
It is unlikely that appreciable quantities of water will flow through
stockpiled materials, even with irrigation. This idea would initially be
tested by measurements of water movement in access tubes. The results should
be corroborated by analyses of field infiltrometer tests conducted during the
previous step. If little water movement is found, monitoring would subse-
quently be limited to monthly measurements with the neutron probe. If appre-
ciable water movement is indicated, then the alternative methods discussed
above would be limited at a later date.
Costs for this step would include: labor costs for conducting and ana-
lyzing neutron probe measurements, operational costs for installing access
tubes, and capital costs for the neutron logger, steel pipe and miscellaneous
materials for construction of access tubes. These costs are summarized in
Appendix B, Table B-l.
16
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Evaluate Attenuation of Pollutants in the Saturated Zone
The general purpose of this step is to measure or estimate the attenua-
tion of source pollutants during migration in the zone of saturation. The
pollutants of concern will be those which have not been completely attenuated
during movement through the vadose zone.
Monitoring Needs—
Whether monitoring is justified to determine attenuation of pollutants
in the saturated zone as may be affected by stockpiles will depend entirely
upon whether water will penetrate through the piles and the underlying mate-
rial to groundwater and, if it does, whether it would carry significant quan-
tities of pollutants in excess of those existing in the natural groundwater
system. Both possibilities are unlikely. The stockpiled material may be
highly permeable, but the underlying soil will probably be less so due to
scraping and compaction. If the stockpile is placed on compacted mine spoil
with a characteristically large, shale-derived component, penetration of
water to the saturated zone will be greatly restricted. Furthermore, the
only pollutants other than those which occur naturally or through oxidation
would come from fertilizer applications, principally nitrates. Since ferti-
lizer would only be used to assist the development of a protective vegetative
cover and not for agricultural production, application will be light.
Preliminary Recommendations--
No monitoring would be done during this step unless indicated by the
results of previous steps. Labor, operation, and capital costs, as well as
monitoring methodology, for sample collection and well installation are sum-
marized in Appendix B, Table B-l (define hydrogeologic situation and study
existing groundwater quality), should monitoring in the saturated zone be
required.
EXAMPLE CASE STUDY--AMAX BELLE AYR SOUTH
Identify Potential Pollutants
Stockpiled topsoil at the AMAX Belle Ayr South Mine was selected for
study as being the most representative in the project area. The location of
the topsoil stockpile is shown in Figure 1. The soils on the lease area were
mapped on a reconnaissance level by the Soil Conservation Service (SCS) in
1939. Two soil series, the Arvada and Haverson, have high sodium adsorption
ratios and calcium concentrations at depth. A review of the mine plan shows
that these poor-quality soils are not specifically excluded from topsoil
stockpiles at the Belle Ayr South mine. The U.S. Geological Survey (1976)
states that 86 samples from four areas of the mine were analyzed. The sodium
adsorption ratio was found to range between 0.2 and 7.5, with an average of
2.62; electrical conductivity varies from 0.13 to 1.53 mmhos, with an average
of 0.81 mmho; and pH ranges between 7,2 and 8.1, with an average of 7.6.
Trace element analyses are not available.
17
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00
Figure I. AMAX Belle Ayr South topsoil stockpile location.
-------
AMAX Coal Co. prepares soil inventory maps of the lease area prior to
mining as part of their Soil-Overburden Analysis Program. The program in-
cludes the development of maps of major soil series for review by the SCS.
At least two sites in each soil series are sampled for analyses which include
the following determinations: organic matter, electrical conductivity, pH,
nitrogen, phosphorus, potassium, calcium, magnesium, sodium, selenium, boron,
and molybdenum. There is no monitoring program for topsoil material after it
is stockpiled.
Monitoring gaps include: an evaluation of the chemistry of the stock-
piled soils, change in chemistry due to any fertilization or irrigation of
the stockpiles, and physical and chemical changes in the stockpiled materials
over long periods of time.
Define Groundwater Usage
The U.S. Geological Survey (1975) states that pit discharge will be used
for dust control, with the excess being discharged to Caballo Creek. Pit
discharge is about 100,000 gallons per day, and it was stated that as much as
80,000 gallons per day could be used for dust suppression during the summer.
According to AMAX Coal Co. (1976), seepage to the pit is currently being
totally consumed for dust control. Pit discharge decreased somewhat as the
pit size increased; however, it still amounts to about 100,000 gallons per
day.
A wash house has been constructed to serve 102 people. Water for this
facility comes from wells drilled in the area; estimated usage is 2,500 to
4,000 gallons per day.
According to AMAX Coal Co. (1976), irrigation of reclaimed lands is not
planned, but this does not preclude consideration at a later date should the
situation warrant it. Topsoil stockpiles will require irrigation to estab-
lish and maintain vegetative cover. Approximately 3 acres of land will be
required to store the topsoil from 50 mined acres and this would require from
1 to 2 million gallons of water per year to satisfy plant water requirements.
Define Hydrogeologic Situation
The regional hydrogeology of the AMAX Belle Ayr South lease has been
summarized in Everett (1979).
Caballo Creek is the dominant surface feature on this lease site, flow-
ing from west to east through the center of the area to be mined. The land
near the stream is practically flat, rising to the north and south of Caballo
Creek (U.S. Geological Survey, 1975).
The northwestern part of the lease is covered with rolling upland grass-
lands, with the terrain south of the river being more rugged with deeper
washes and steeper slopes than those found north of the rivers. The east
edge of the lease is characterized by topography typical of physiographic
division number 2, forming a series of low, abrupt hills caused by the burn-
ing coal.
19
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A considerable amount of data has been collected on aquifer performance
through pumping tests. However, monitoring gaps exist regarding specific
information on the hydrogeology in the vicinity of the stockpile areas, the
hydraulic characteristics of the stockpiled materials, and the depth of the
local water table.
Study Existing Groundwater Quality
Numerous groundwater quality samples have been collected by workers at
the Belle Ayr South Mine. Although detailed sample collection procedures
were not outlined in the Mining Plan Update (AMAX, 1977), the results of sev-
eral analyses were reported. Tables 2 through 5 show the maxima and minima
of these results, as well as the mean values. Significant deviations occur
for some parameters, indicating a dynamic quality situation or sampling and
analytical inconsistencies. Figures 2 and 3 are trilinear plots of the mean
concentrations of major undissolved species.
In its mining plan update, AMAX states that the dominant water types
within the Wasatch Formation are sodium sulfate and sodium bicarbonate. How-
ever, the data summarized in Figure 2 show that well N-5 would be classified
as a calcium sulfate water. Analyses which reflect the reported sodic qual-
ity of the Wasatch waters should be compiled and reviewed. The plots on
Figure 3 indicate that water types vary from location to location, and that
the coal seam waters can be either sodic or calcic. AMAX's deep Fort Union
water at well station WRRI-7 has seriously high sulfate contents for a pota-
ble water source. AMAX did not present data on other Fort Union wells which
are reportedly used for office and shop requirements. The analysis presented
for the scoria pit (Table 2) has a close epm balance (0.97), but the reported
electrical conductivity is inconsistent with the rest of the results. If
this inconsistency is ignored, the scoria pit water appears to be of fairly
good quality. However, the relative amounts of groundwater inflow and sur-
face runoff that make up this pit water are unknown, and it is assumed that
groundwater within the scoria is not as good as this analysis might indicate.
Monitoring gaps include analysis of potable water from the deep Fort
Union wells, characterization of the Wasatch waters, site-specific water
quality in the coal seams, and reevaluation of the inconsistencies in the
reported water quality information.
Evaluate Infiltration Potential
Monitoring to determine the infiltration potential of stockpiled materi-
als is not done at the Belle Ayr South Mine.
Evaluate Mobility in the Vadose Zone
No monitoring of water or pollutant mobility exists for the stockpiles
or in the underlying vadose zone.
20
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TABLE 2. AMAX BELLE AYR WATER QUALITY—WASATCH FORMATION
ABOVE THE COAL (AMAX, 1977)a
Parameter
Field pH
Calcium
Magnesium
Sod i urn
Potassium
Carbonate
Bicarbonate
Oil and grease
Sulfide
Arsenic
Barium
Boron
Cadmium
Copper
Total chromium
Chromium— HEX
Total iron
Dissolved iron
Lead
Manganese
Mercury
Nickel
Selenium
Silver
Zinc
TK nitrogen
Conductivity MBAS
Ammonia
Organic nitrogen
Nitrate + nitrite
Chloride
Fluoride
Cyanide
Sulfate
Phenol
MBSA
BOD
COD
Total dissolved solids
Suspended solids
SV solids
Lab pH
Turbidity (JTU)
Total C03
Hardness
Al kal ini ty
Number of
analyses
1
12
12
12
11
12
10
12
4
5
5
5
5
5
4
1
8
8
5
5
4
5
4
5
5
11
12
6
1
1
12
9
4
12
5
5
1
12
12
7
6
11
7
11
12
3
Maximum
value
7.5
279.
208.
200.
13.0
610.
705.
21.6
0.9
0.007
0.5
0.6
0.014
0.01
0.1
0.01
5.7
5.0
0.1
0.27
0.001
0.1
0.002
0.5
0.12
1 .0
2,760.
0.0
0.9
0.0
46.0
0.6
0.02
1,369.
0.034
0.14
31 .0
28.4
2,300.
178.
100.
7.9
29.0
310.
1,550.
516.
Minimum
value
7.5
180.
59.0
113.
0.0
0.0
500.
0.0
0.0
0.007
0.5
0.0
0.01
0.01
0.1
0.01
0.1
1.8
0.01
0.1
0.001
0.1
0.001
0.05
0.01
0.3
1 ,580.
0.0
0.9
0.0
16.0
0.3
0.008
650.
0.0
0.1
31.0
0.4
1,480.
8.0
0.0
7.2
1 .3
250.
742.
346.
Standard
Mean deviation
7.5
213.
145.
164.
9.52
101.
604.
2.55
0.3
0.007
0.5
0.164
0.0108
0.01
0.1
0.01
2.59
3.20
0.082
0.186
0.001
0.1
0.013
0.41
0.052
0.682
2,211.
0.0
0.9
0.0
21 .9
0.511
0.011
980.
0.0074
0.108
31.0
8.71
1,877.
38.4
22.3
7.53
10.9
294.
1,138.
454.
30.6
37.2
27.6
4.80
237
51 .0
6.08
0.408
0.246
0.0018
1.70
1.19
0.0402
0.0623
0.0005
0.201
0.0432
0.252
310.
8.17
0.105
0.006
205.
0.0149
0.0179
9.19
250.
61.7
38.7
0.211
9.76
16.7
211.
93.8
aValues in mg/1 unless specified; Uell station N-5; June 1972 to June 1976.
21
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TABLE 3. AMAX BELLE AYR WATER QUALITY DATA—SCORIA PIT—WASATCH FORMATION
ABOVE THE COAL (AMAX, 1977)
Number of
Parameter analyses
Field pH
Ca 1 c i urn
Magnesium
Sod i urn
Potassium
Carbonate
Bicarbonate
Cadmium
Copper
Total iron
Lead
Manganese
Mercury
Silver
Zinc
Conductivity (ymhos)
Chloride
Sulfate
Hardness
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
Maximum
7.6
160.
25.0
45.0
18.0
0.0
156.
0.001
0.01
0.07
0.01
0.002
0.002
0.05
0.02
504.
29.0
456.
21.0
Minimum
7.6
160.
25.0
45.0
18.0
0.0
156.
0.001
0.01
0.07
0.01
0.002
0.002
0.05
0.02
504.
29.0
456.
21.0
Mean
7.6
160.
25.0
45.0
18.0
0.0
156.
0.001
0.01
0.07
0.01
0.002
0.002
0.05
0.02
504.
29.0
456.
21.0
Values in mg/1 unless specified; well station scoria pit; June
1972 to June 1976.
22
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TABLE 4. AMAX BELLE AYR WATER QUALITY DATA — WYODAK COAL (AMAX, 1977)a
Parameter
Field pH
Calcium
Magnesium
Sodium
Potassium
Carbonate
Bicarbonate
Oil and grease
Sulfide
Arsenic
Barium
Boron
Cadmium
Copper
Total chromium
Chromium-HEX
Total iron
Dissolved iron
Lead
Manganese
Mercury
Nickel
Sel em" urn
Silver
Zinc
TK nitrogen
Conductivity (pmhos)
Ammonia
Organic nitrogen
Nitrate + nitrite
Chloride
Fluoride
Cyanide
Sulfate
Phenol
MBSA
BOD
COD
Total dissolved solids
Suspended solids
SV solids
Lab pH
Turbidity (JTU)
Total C03
Hardness
Al kalinity
Number of
analyses
1
12
12
12
10
12
12
12
4
5
5
5
5
4
4
1
9
7
5
5
4
5
4
5
5
11
12
6
1
1
12
10
4
12
5
5
1
12
12
8
6
11
8
11
12
3
Maximum
value
7.0
360.
320.
640.
14.0
0.0
560.
12.1
1.1
0.007
0.5
1.1
0.01
0.01
0.1
0.01
5.1
2.5
0.1
2.0
0.001
0.1
0.001
0.5
2.3
3.9
4,740.
1.3
3.1
0.0
31 .0
1.3
0.02
3,400.
0.005
0.16
20.0
345.
5,160
232.
40.0
7.9
125.
270.
2,200
450.
Minimum
value
7.0
180.
12.0
103.
8.8
0.0
290.
0.0
0.1
0.007
0.5
0.0
0.001
0.01
0.1
0.01
0.2
1.49
0.02
0.1
0.001
0.1
0.001
0.05
0.08
1.1
1,720.
0.0
3.1
0.0
3.6
0.4
0.008
680.
0.001
0.1
20.0
28.0
1 ,400.
8.0
6.0
7.0
5.0
140.
530.
225.
Hean
7.0
208.
91 .4
210.
11.7
0.0
510.
2.34
0.525
0.007
0.5
0.27
0.0082
0.01
0.1
0.01
2.19
2.07
0.084
0.774
0.001
0.1
0.001
0.41
0.56
2.59
2,077.
0.283
3.1
0.0
9.16
0.75
0.011
940.
0.0026
0.112
20.0
71.6
1,785.
68.2
21.8
7.23
29.4
251.
896.
373.
Standard
deviation
49.1
75.2
138.
1.44
74.1
3.55
0.505
0.465
0.004
1.65
0.379
0.0358
0.839
0.201
0.974
0.856
841 .
0.523
7.46
0.222
0.006
774.
0.0018
0.0268
88.4
1,063.
74.7
11.9
0.246
40.0
37.7
422.
128.
aValues in mg/1 unless specified; well station N-3; June 1972 to June 1973.
23
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TABLE 5. AMAX BELLE AYR WATEK QUALITY DATA—FORT UNION FORMATION
BELOW COAL (AMAX, 1977)a
Parameter
Field pH
Calcium
Magnesium
Sodium
Potassium
Carbonate
Bicarbonate
Oil and grease
Sulfide
Arsenic
Barium
Boron
Cadmium
Copper
Total chromium
Chromium— HEX
Total iron
Dissolved iron
Lead
Manganese
Mercury
Nickel
Selenium
Silver
Zinc
TK nitrogen
Conductivity (pmhos)
Ammonia
Organic nitrogen
Nitrate + nitrite
Chloride
Fluoride
Cyanide
Sulfate
Phenol
MBSA
BOD
COD
Total dissolved solids
Suspended sol ids
SV solids
Lab pH
Turbidity (JTU)
Total C03
Hardness
Alkalinity
Number of
analyses
1
12
12
12
9
12
12
12
4
5
5
5
5
5
4
1
8
8
5
5
4
5
4
4
5
11
12
6
1
1
12
9
4
12
5
5
1
11
12
7
6
11
7
11
12
3
Maximum
value
7.7
227.
85.0
243.
10.0
0.0
440.
6.0
3.0
0.02
0.5
0.6
o.of
0.01
0.1
0.01
2.2
1 .9
0.1
0.23
0.001
0.1
0.001
0.5
0.44
3.5
1,870.
0.3
1 .5
0.0
46.0
1.6
0.02
770.
0.047
0.5
9.0
18.0
1,500.
206.
108.
7.8
44.0
220.
700.
330.
Minimum
value
7.7
121.
36.0
154.
8.8
0.0
331.
0.0
0.0
0.007
0.5
0.0
0.001
0.01
0.1
0.01
0.1
0.27
0.01
0.0
0.001
0.1
0.001
0.05
0.04
0.4
1,600.
0.0
1 .5
0.0
3.6
0.3
0.000
600.
0.001
0.1
9.0
1.2
1,270.
4.0
0.0
7.3
0.7
190.
450.
162.
Mean
7.7
157.
46.4
220.
9.33
0.0
398.
1.72
1.07
0.0096
0.5
0.158
0.0082
0.01
0.1
0.01
0.788
0.853
0.082
0.118
0.001
0.1
0.001
0.387
0.132
1 .81
1,791.
0.05
1 .5
0.0
12.1
0.555
0.011
728.
0.012
0.18
9.0
8.16
1,400.
47.7
29.3
7.48
10.0
199.
572.
274.
Standard
deviation
26.1
12.6
23.3
0.377
25.1
2.01
1.39
0.0058
0.249
0.004
0.709
0.537
0.0402
0.0823
0.225
0.172
0.785
80.1
0.122
11.7
0.397
0.006
47.5
0.0197
0.178
6.30
62.9
72.6
44.0
0.166
15.3
8.39
58.4
96.9
Values in mg/1 unless specified; well station URRI 7.
24
-------
80
60 40
Ca
CATIONS
80
PERCENTAGE REACTING VALUES
ANIONS
Figure 2. Water-analysis diagram, Belle Ayr South Wasatch Formation,
N-5 and scoria pit (SP) wells.
25
-------
v\ *
80
CATIONS PERCENTAGE REACTING VALUES ANIONS
Figure 3. Water-analysis diagram, Belle Ayr South Wyodak
coal mean values.
26
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Evaluate Attenuation of Pollutants in the Saturated Zone
Source-specific monitoring in the saturated zone underlying present
sites of stockpile materials is lacking. Data on the infiltration potential
and mobility in the vadose and saturated zones could be developed through the
monitoring methodology in the topsoil generic case study.
27
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SECTION 3
MONITORING DESIGN FOR MINE WATER SOURCES
GENERAL CASE CONSIDERATIONS
Identify Potential Pollutants—Sedimentation Ponds
Potential sources of pollution which may affect the quality of water
within sedimentation ponds include pit discharge, sewage effluent, and sur-
face runoff. Pit discharge may contribute a large amount of suspended solids,
some or all of the major inorganic chemical constituents (calcium, magnesium,
potassium, sodium, bicarbonate, carbonate, chloride, sulfate, sulfide, phos-
phate, etc.), and trace contaminants (including iron, manganese, zinc, copper,
cadmium, chromium, arsenic, lead, molybdenum, vanadium, uranium, thorium,
radium, and selenium). Among the potential pollutants in ammonium-nitrate
fuel oil (ANFO), used as an explosive for overburden removal, are nitric
oxide, nitrogen dioxide, nitrous oxide, ammonia, hydrogen cyanide (1/10 of a
pound of cyanide is produced for each 120-ton charge of ANFO), fuel oil, and
trace organics. Gasoline, diesel fuel, and oil may be introduced by heavy
equipment working in the pit.
Pollutants introduced into the sedimentation ponds from an on-site pack-
age plant include major inorganics and trace contaminants, organics (measured
by BOD, COD), and microorganisms (see "Potential Pollutants," Everett, 1979).
Surface runoff into the pit includes both sediment and wastes deposited on
the ground surface, such as oils, chemical spills, salts, etc., as well as
salts, organics, and microorganisms flushed from the soil surface.
Monitoring Needs--
Monitoring needs include: characterization of the sources of possible
pollutants entering the sedimentation ponds, identification of potential
pollutants entering the ponds, and determination of the chemical characteris-
tics of the water in the ponds themselves.
Alternative Monitoring Approaches--
One method of characterizing potential pollutants would be to collect
pollutant-specific information on monitoring activities relating to the sedi-
mentation pond. For example, water quality data may be requested, together
with information on the status of an NPDES permit for the basin. The NPDES
usually also requires monitoring of flow, pH, TSS, Mg, and Fe.
28
-------
Alternatively, the quantities of water discharging into the ponds from
the main sources of potential pollution could be measured or otherwise deter-
mined in order to characterize pollutant loading. For example, flow meters
could be installed within the pipeline or lines used to transport pit water
to the ponds. Similarly, a Palmer-Bowl us flume or a weir could be placed in
the line from the package plant. The watershed area above the pond could be
characterized, and a rainfall-runoff relationship developed using techniques
in the SCS National Engineering Handbook (Soil Conservation Service, 1972).
Another nonsampling method would comprise inventorying sources contrib-
uting possible pollutants to the sedimentation ponds. For example, the mass
of ANFO used in overburden removal and coal fracturing could be determined.
Sources contributing to the package plant could be inventoried during a par-
allel program. The surface runoff area above the ponds could be examined for
surface stockpiles (e.g., topsoil, coal refuse, oil drums, etc.) containing
potential pollutants. The sources could be located on a suitable base map.
Measurement of overflow from the ponds is required for an NPDES permit
and these flow data may be used as part of the nonsampling program.
To obtain overflow measurements, appropriate weirs or flumes could be
installed in a well-defined reach of the river into which the ponds discharge
or as close as possible to the ponds. An automatic stage recorder could be
installed for continuous measurement.
Water samples for characterizing pollutants within the sedimentation
ponds and downstream runoff could be obtained from a number of alternative
locations. For example, pit water discharging into the sedimentation ponds
could be sampled directly at the pipeline discharge point. Similarly, sam-
ples of package plant effluent and surface runoff into the ponds could be
obtained within the ponds and from the outfall to determine water quality
transformations in transit. Finally, surface runoff comprising pond overflow
could be sampled at a number of downstream locations.
Alternative water sampling methods include grab sampling, automatic com-
posite sampling, and automatic discrete sampling. Grab samples are obtained
to determine instantaneous water quality. Composite samplers are used to
obtain blended water samples over a certain time interval (e.g., 24 hours).
Discrete samplers extract water samples at timed intervals. The relative
advantages and disadvantages of these techniques for wastewater sampling are
reviewed by Harris and Keefer (1974).
Three alternative methods are possible for analyzing water samples.
First, all samples may be submitted to a laboratory for complete analyses,
including: suspended sediment; major inorganics (Ca, Mg, IMa, K, HCC^, Cl,
S04, P04, SiC>2, NH3-N, total-N, pH, and EC); trace constituents (Fe, Mg, Zn,
Cu, Cl, Cr, As, Mo, V, U, Th, Ru, and Se); cyanide (possible byproduct of
ANFO); organics (oils, grease, ); and microorgani sms (total and fecal col i-
form). Recommended quality control measures (e.g., submitting duplicate sam-
ples to other EPA-audited laboratories) could be an integral part of this
approach.
29
-------
A second technique is to analyze completely the first few water samples
collected during the program. Subsequently, those trace constituents found
to be present in low concentrations could be excluded from further analyses.
Similarly, cyanide, low-level organics, and microorganisms could be deleted
from routine analyses. It is recommended, however, that each sample be com-
pletely analyzed for the major organics. Similarly, package plant effluent
would always be checked for BOD and coliforms. Quality control measures
could be implemented.
A third method is to analyze samples in the field for constituents such
as chloride and nitrate. This approach would require the purchase of a por-
table field kit (e.g., Hach Engineering Laboratory). When the results of
such checks indicate a substantial change between testing, samples could be
collected for laboratory analysis.
Selecting a sampling frequency to characterize the water-borne pollu-
tants in a source, such as the sedimentation ponds, is generally a trial-and-
error process. One alternative method is to sample frequently (e.g., every
hour using a 24-hour discrete sampler) until time trends in the quality of
the source are characterized. Subsequently, samples could be obtained by
periodic grab sampling (e.g., weekly or monthly). An increase in sampling
frequency may be warranted by unusual circumstances. For example, a spill of
toxic substances on the watershed area draining into the ponds may justify an
increase in sampling frequency.
Sampling frequency is also related to analytical costs. Thus, complete
laboratory analyses of 24 samples collected during the 24-hour cycle of a
discrete sampler could be prohibitively expensive. In this case, it could be
more economical to obtain 6- or 12-hour discrete samples or a single 24-hour
composite sample.
Preliminary Recommendations--
All of the above methods are deemed to be of importance in a program for
identification of potential pollutants. However, source characterization,
e.g., package plant discharge, will be included in parallel monitoring pro-
grams and will not be considered here. Similarly, inflow-outflow rate rela-
tionships will be considered as a sampling item under "Evaluate Infiltration
Potential." Consequently, the following preferred monitoring approach is
recommended:
• Available data on water quality would be obtained, including
information on the NPDES permit.
• Samples of pit water, runoff from disturbed areas, and sewage
effluent discharging into the detention basin would be collected
via composite or discrete samplers. As discussed below, these
samples would be used to characterize incoming quality trends
and to assist in determining quality transformations in water
during transit through the basin. In addition, time trends in
certain quality parameters (e.g., BOD) may be warranted from re-
sults of parallel studies on the package plant. Subsequently,
30
-------
when trends are apparent, grab (discrete) samples would be
collected.
• Surface runoff flowing into the ponds would be grab sampled at
the inlet point.
• Discrete (grab) water samples would be taken at two or three
areal locations within each pond and at two or three depths at
each location, to characterize qua!ity transformations during
transit of water through the ponds.
• Pond discharge would be grab sampled at the outfall point and at
two or three downstream locations.
All water samples would be collected, preserved, and transported in
accordance with recommended procedures (see Brown, Skougstad and Fishman,
1970).
The following approach is recommended for analyses of water samples
collected from the sedimentation ponds.
• Analyze completely the first five water samples from each sam-
pling location for all constituents. Quality control measures
would be implemented.
• Analyze field samples for representative constituents (e.g.,
nitrate, chloride). Collect samples for complete analysis if
substantial changes in concentrations of these parameters occur
during the nonsampling period.
• Analyze water samples collected on the basis of results under
the second step, only for those constituents found during the
first step to be present in above-permissible concentrations.
Note, however, that the major inorganics would be completely
analyzed and package plant effluent would be checked for BOD and
microorganisms. Quality control measures would be implemented.
A preferred approach to sampling frequencies for sampling points related
to the sedimentation ponds includes:
• Pit water and package plant effluent would be sampled at their
respective discharge points on a 6-hour and 12-hour basis, using
discrete samplers, three or four times a week for four weeks, or
until time trends in quality are characterized. Thereafter,
grab samples would be obtained on a semimonthly basis, unless
more frequent sampling is warranted (e.g., discharge of toxic
chemicals from the pit).
• Surface runoff would be grab sampled at the inlet point to the
pit during one or two snowmelt runoff events and during one or
two summer discharge events.
31
-------
• Water samples would be collected at two locations in each of the
two ponds at weekly intervals until quality trends are estab-
lished. Thereafter, water samples would be obtained every month.
• Water samples would be collected at the outfall point from the
detention basin at the same frequency and at the time that
inflow discharges are sampled; that is, samples would be col-
lected on a 6- or 12-hour basis, three or four times a week,
until quality trends become apparent. Thereafter, a discrete
sample would be collected twice a month. Water samples would be
obtained when available from the outflow channel. If flows are
sustained, samples would be taken twice a month.
The overall costs of this step would be high initially because of the
need for complete analysis of source samples. These costs are summarized in
Appendix B, Table B-2, and given below. Later, the sampling frequency and
requisite analyses would be reduced. The process of using field checks to
determine sampling frequency is another cost-reducing technique.
• Labor costs for inventorying and characterizing sources, in-
stalling and operating water sampling equipment, field checking
quality, and collecting and transporting samples.
• Capital costs for purchasing composite or discrete samplers, and
for equipment for field checking quality (Hach Kit). These items
would generally be capital items available for the overall TEMPO
monitoring program. Consequently, the proportionate charges
against this source would be low.
• Operating costs for analyzing samples. These costs would be
high initially but would lower as the list of constituents to
examine is narrowed and when field checks are used to guide
sampling.
Identify Potential Pollutants—Pit Water
Water entering the coal mine pits can originate from a number of sources,
each of which may contribute pollutants. Common methods of disposal of pit
water are discharge to sedimentation ponds and subsequent discharge to sur-
face water, and use in dust control, such as for roads in the mine area.
Monitoring of pit water disposal is discussed earlier in this section. Of
concern in this discussion is the monitoring of water in the pit itself, and
secondarily, determining the origin of the pollutants contained therein.
Thus, the monitoring approach herein focuses on identification of potential
pollutants. The subsequent steps of the monitoring methodology are applicable
to the disposal processes and are not discussed further in this section.
Water in the pits may come from a number of sources: groundwater in the
coal seam, groundwater percolating from nearby stream channels, through allu-
vium beneath the floodplain, groundwater in the overburden, groundwater in
interburden and underburden, groundwater in spoils, direct precipitation,
32
-------
surface runoff into the pit, and waste disposal, such as sewage treatment
plant effluent.
There are a number of potential sources of pollutants in the pit water,
and most of these are discussed elsewhere in this report. Pollutants may
come from: coal, overburden, interburden and underburden, explosives,
spoils, solid waste disposal, polluted streamflow, liquid waste disposal, air
pollutants and polluted precipitation, and spills and leaks. Some of these
pollutants may be derived from natural sources. However, the modified hydro-
geologic framework may allow them to enter the pit water.
Monitoring Needs-
There is a need to determine the quality of water in the pit and of
discrete sources of water entering the pit. Secondarily, there is a need to
determine the origin of pollutants present in pit water. This will likely
entail additional monitoring beyond the pit. For example, effluent from a
sewage treatment plant may percolate and move into the pit. Groundwater may
also pick up substantial amounts of inorganic constituents from in-place and
disturbed geologic formations or spoils during movement toward the pit.
Alternative Monitoring Approaches—
A water budget approach using existing data and field measurements could
be used to determine the amount of water in the pit.
Pit water discharge could be measured by installing a continuously re-
cording flow meter in the discharge lines and keeping an account of the num-
ber of truckloads of water hauled for dust suppression. Precipitation falling
on the water surface could be measured by installing a continuously recording
rain gage near the pit bottom. Evaporation could be measured indirectly by
installing a floating evaporation pan. For both precipitation and evaporation
determinations, the area of water surface in the pit must be known. This can
be determined by periodic land surveys, such as on a monthly basis. Aerial
photographs could also be taken at a similar frequency to document the loca-
tion of water bodies in the pit.
The volume of water entering the pit is more difficult to determine.
This is because the water may come both from discrete sources, such as leak-
age at one location from a stream channel, and diffuse sources, such as seep-
age. Surveys of operating mines indicate that discrete sources may be preva-
lent. For these sources, flumes or weirs could be installed near the point
of entrance to the pit. Groundwater seepage into the pit from diffuse sources
can be calculated if water table slopes and aquifer characteristics are known.
This information would be developed in defining the hydrogeologic situa-
tion. Alternatively, the groundwater seepage could be characterized by a
network of monitoring wells surrounding the pit. Aquifer tests would be
necessary to determine transmissivity and water-level measurements to deter-
mine the hydraulic gradient.
33
-------
Items other than pit inflow and discharge could be measured, including
change in storage for water in the pit. A staff gage used in conjunction
with aerial photographs, or water surface area surveys could be used to de-
termine change in pit water storage. Additionally, leakage from the pit
could be estimated after other water budget items have been determined.
Water samples should be collected from pit water and discrete sources of
water entering the pit. For water in the pit, samples could be taken repre-
sentative of various depth intervals, since the water quality may vary sub-
stantially with depth in the pit. A depth-integrated sampler could be used
from a small boat which would allow access to various parts of the pond. A
composite sampler could be used to continuously monitor the quality of the
water removed from the pit for use or dewatering. Grab samples could be col-
lected from discrete sources of inflow to the pit. Sediments beneath the pit
water should also be collected for sampling.
For groundwater in the coal seam, overburden, underburden and spoils,
wells could be installed at the periphery of the pit to collect water sam-
ples. Changes in water quality along flow paths could be determined as
groundwater approaches the pit. Generalized data from operating, mines indi-
cate that the effects of pit dewatering do not extend out more than a few
miles. Thus, these monitor wells should be placed within h mile or less of
the pit. For groundwater percolating from streams, water samples could be
collected from streamflow. Wells could be installed to allow collection of
water samples from the alluvium. Changes in water quality during percolation
could be determined as groundwater approaches the pit. Both solid and liquid
wastes that could affect the quality of pit water could be sampled for chemi-
cal analyses. In general, the latter type of monitoring would generally have
the lowest priority, unless sampling of pit water suggested the necessity for
this approach.
Water entering the upper part of a pit can traverse significant distances
before jo.ining the pit water body. In this case, the water could pick up a
number of pollutants from spills, native or disturbed materials, and other
sources. In this case, sampling traverses could be made following the course
.of the water flow.
Monitor wells should be constructed to allow aquifer testing. These
tests are advisable for some monitor wells because it allows the optimal de-
termination of aquifer transmissivity. Transmissivity values provide key
input for calculating the rate of groundwater flow, which is crucial in
placement of monitor wells relative to pollution sources. An 8-inch diameter-
casing is necessary to provide room for the submersible pump (often 4 to 6
inches in diameter), plus a 1-inch diameter access tube for electric sounder
measurements. For aquifer testing the pump is not permanent, and since PVC
is the preferred casing material, extra room should be provided so that the
casing is not damaged during pump installation and removal. For depths ex-
ceeding 100 feet or so, most casing strings are not perfectly straight, thus
extra room is advisable. An 8-inch diameter casing is generally adequate for
pumping lifts of up to 500 feet, assuming the range of well yield normally
encountered in the coal regions. A 3-inch thick gravel pack is generally
recommended; however, a 2-inch gravel pack would suffice for shallow wells
34
-------
(i.e., alluvium). Thus, the hole diameter would generally be 14 inches, but
possibly 12 inches.
For monitor wells that are not to be pump tested, where water levels are
shallow, and where a fixed pump is placed, a 4-inch diameter PVC casing could
be used. In cases such as monitoring groundwater quality in alluvium, such a
diameter would be feasible. For deeper water levels or where portable pumps
are used, a 6- or 8-inch casing is advisable. In many cases, use of a some-
what larger diameter casing is the least expensive procedure in the long
term. Larger diameter wells are easier to develop, easier to sample, and
provide maximum flexibility for use. For example, a water-level recorder
could be more easily installed in a larger well.
An annular seal would be placed opposite the upper 10 to 20 feet of the
well. The wells should be properly developed upon completion to remove drill-
ing mud or other foreign materials. The top of the casing should extend sev-
eral inches above the ground surface and a locking cap should be installed.
Barriers should be constructed to prevent destruction. Thus, it may be ad-
visable to deliberately construct the monitor wells in a manner that allows
retrieval of the casing at a later date. Obviously as the pit moves, some
wells will have to be destroyed and new ones drilled.
The general drilling procedure in the Gillette area is to use the air
rotary method for overburden or coal above the water table. Thus, holes are
drilled by air until saturated conditions prevail, and then mud is added and
the air drilling is by direct rotary, with a drilling fluid circulated. Ben-
tonite is commonly used for drilling below the water table. Clinker is a
special case, and may be rather easily drilled above the water table. How-
ever, lost circulation commonly occurs below the water table, even when
drilling mud is used. Thus bran, fiber, cement, or other materials may be
added. For alluvium, a common procedure is to drill an 8-inch diameter hole
with a flight auger and install a 4-inch diameter PVC casing, and a 2-inch-
thick gravel pack. In general, the alluvium is usually less than 20 feet
thick and clay-rich with lenses of sand and gravel. Annular well seals are
usually provided by using bentonite.
In general, the methods of well drilling in use are suitable. However,
considerable attention should be given to well development. It may also be
advisable to use a biodegradable drilling mud. Monitor wells can be swabbed
and bailed, air or water jetted, and finally pumped and surged. Use of a
larger diameter casing enhances proper well development.
To obtain water samples, a portable submersible pump should be installed
in the monitor well. Upon completion of the well, a pump should be installed,
pumping commenced, and water samples collected at frequent intervals during
the first few hours of pumping. For alluvium, test durations of about 24
hours are generally adequate. For consolidated rock aquifers and clinker,
durations of 1 week to 1 month are advisable. A step-drawdown test is advis-
able during the first part of the test to determine well losses. In general,
several observation wells are advisable for consolidated rock aquifers where
fractures result in anisotropic conditions. Often other monitor wells can be
used for this purpose. Water should be piped a sufficient distance from the
35
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pumped well to ensure that no recirculation occurs during the test. A 1-inch
diameter sounding line should be provided to allow water-level measurements
by electric sounder. Totalizing propeller-type flow meters or orifice plates
should be used to measure the flow. Electrical conductivity, pH, and temper-
ature of discharged water should be periodically measured during the pump
test. About six water samples should be collected at different times during
the test for chemical analysis of parameters to be monitored. Field deter-
minations of pH, EC, oxidation potential, and other parameters can be made.
The procedure could be followed simultaneously with aquifer testing to avoid
duplication. From such data, the optimum duration of pumping prior to water
sample collection can be determined. Proper sample collection procedures are
given by Brown, Skougstad, and Fishman (1970) and Thatcher, Janzer, and
Edwards (1977).
In general, pumping is the preferred method of sampling where well yields
exceeding about h gpm can be obtained. Airlifting is commonly used in the
Gillette area and may be the most feasible approach where wells yield less
than ^ gpm. However, consideration must be given to changes in chemical com-
position that may be induced by the airlifting process.
A quarterly sampling frequency is adequate for overburden and coal, and
semiannual sampling is adequate for deeper materials. In Wyoming, the DEQ
specifies sampling monitor wells twice a year. Due to weather conditions and
access problems, this is usually done early in the summer and late in the
summer. Quarterly sampling is advisable where access is feasible. The great-
est constraint to more frequent sampling in many western coal regions is ad-
verse weather conditions.
Samples of water should be examined for the major inorganic chemical
constituents, including pH, EC, and TDS (residue at 180°C). Selected sam-
ples should be examined for total dissolved solids (ignition 600°F). Such
determinations allow comparison of cation-anion sums, total dissolved solids
versus electrical conductivity, and calculated total dissolved solids versus
residue. Boron, phosphorus, and fluoride should be determined on all samples.
Proper sample treatment and filtration techniques should be used (Brown,
Skougstad and Fishman, 1970). The various nitrogen forms should occasionally
be determined. Trace elements that are recommended for frequent determina-
tions include iron, manganese, cadmium, chromium, arsenic, lead, molybdenum,
vanadium, cyanide, and selenium. However, an extensive list of trace ele-
ments should be determined early in the program and annually thereafter.
A gross indication of the organic chemical composition can be obtained
by total organic carbon and dissolved organic carbon determinations. Oil,
grease, gasoline, and selected pesticides should be determined early in the
program and annually thereafter. For radiologic composition, the uranium and
thorium contents and gross alpha activity, gross beta activity, and radium-226
activity should be determined. For bacteriologic composition, total coliform
and fecal coliform should be determined.
36
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Preliminary Recommendations--
A recommended general procedure is to perform the most complete analyses
on the pit water. Existing information on discrete and diffuse sources could
be compiled and reviewed and these waters entering the pit would not require
complete analysis, especially once they are characterized.
For solid materials accumulated at the bottom of the pit water, the
nitrogen forms, trace elements, and total organic carbon could be determined
on saturated extracts. Proper quality control procedures for laboratory
analysis should be utilized.
Grab samples of pit water should initially be collected on a weekly ba-
sis. However, prior to initiation of a routine sampling program, the varia-
bility in pit water composition with depth and location should be determined.
Results of this survey can be used to determine the number of samples required
for each sampling round. The sampling frequency may be increased or decreased
depending on results of the first several months of sampling. Alternatively,
a composite sampling device may be necessary if grab samples prove inadequate.
The date and time of sample collection should be determined in light of cli-
matic conditions and operational procedures at the mine that might affect the
quality of water sampled.
Labor costs would include inventorying and characterizing discrete and
diffuse sources and for field checking water quality and sample collection.
Capital expenditures for sampling equipment given in Appendix B, Table B-2,
would not be required if these instruments have been obtained to sample sedi-
mentation ponds. Grab samples of solid waste materials found in the pit
would not require additional equipment. Operating costs would include those
for analysis and transportion and storage of samples.
Define Groundwater Usage
Active coal strip mines require potable water for drinking and bath
house operation, and larger quantities of nonpotable water for equipment
cleanup, shop housekeeping, and dust suppression. Groundwater wells and
seepage and runoff into the pit are the primary sources of these waters.
Monitoring Needs--
Information required to characterize groundwater usage includes the
amount of water needed for various mining activities and the locations of
water supply wel 1 s.
Alternative Monitoring Approaches--
The following nonsampling methods could be used to characterize ground-
water usage: determine current efforts by the mine to quantify groundwater
usage for various mining activities and collect available water use data;
locate water supply wells on a base map (particularly those wells near the
sedimentation pond) by contacting the mine operator or State engineer; obtain
37
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available data on the capacities of wells on-site; install flow-measuring
devices; and estimate pumpage from power consumption data.
Certain of these activities could also be included in future steps.
Specifically, locating water supply wells and determining their specifica-
tions could be undertaken when the hydrogeology of the site and existing
groundwater quality are characterized.
Preliminary Recommendations--
It is recommended that information on the locations and specifications
of water supply wells be collected during this step. Total pumpage in the
wells would be estimated from power consumption data. The entire cost of the
nonsampling program would be for the salary or wages of the project employee
collecting the data and required field transportation. These costs are given
in Appendix B, Table B-2.
Define Hydrogeologic Situation
The site-specific, and to a lesser degree the regional, hydrogeologic
framework of the mine lease area is essential to assessing the overall impact
of mining operation on the hydrologic system.
Monitoring Needs—
In order to characterize the hydrogeologic framework, information is
required in the following areas: location, extent and interaction of aqui-
fers, piezometric surface and velocities of flow, aquifer characteristics,
and local geology.
Alternative Monitoring Approaches--
One nonsampling method would comprise collecting available hydrogeologi-
cal information from a number of sources, including the mine operator, private
consultants, the U.S. Geological Survey, State agencies, etc. Alternative
types of information which could be solicited include: well locations, de-
tails on well construction (construction methods, depth, diameter, locations
of perforations, completion techniques), drillers logs and geophysical data,
and results of pumping tests for aquifer properties (including determining
the particular test methods). Although information germane to the sedimenta-
tion pond area would be given priority, hydrogeologic data on the lease area,
as a whole, could be obtained, i.e., to arrive at a regional picture. If
necessary to complete the regional hydrogeologic picture, data could also be
collected from adjoining mines.
In order to supplement existing groundwater data, a network of wells
could be installed within the vicinity of the selected source area. One
procedure would be to tie in the network with the existing wells. Alterna-
tively, wells could be installed in a pattern suggested by Mooji and Rovers
(1976). This pattern would comprise four wells, with one well upgradient of
the source area, one well downgradient, and the remaining two wells within or
near the source. Three of the wells would terminate in the same (uppermost)
38
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aquifer. The remaining bore hole would comprise a multiple piezometer clus-
ter, with individual piezometers terminating within the same and separate
aquifers. The latter unit would identify vertical hydraulic gradients and
interaquifer leakage. The other three wells would permit defining the orien-
tation of the potentiometric surface of the uppermost aquifers. This surface
would illustrate the possible direction of flow. (Note: in fractured sys-
tems, such as coal aquifers, because of anisotropy, flow may not necessarily
occur perpendicular to the hydraulic gradient. See Davis and DeWiest (1966,
p. 355).)
During construction of the wells, lithological information could be ob-
tained by analyzing drill cuttings for particle-size distribution. The loca-
tions of regions of perched groundwater in the vadose zone may be estimated
by examining drill cuttings. Similarly, some notion of the hydraulic proper-
ties of sediments could be derived from particle-size analysis. Bore holes
could be logged with a variety of geophysical tools (e.g., gamma loggers,
calipers, etc.).
The test wells could be constructed by several techniques, e.g., cable
tool, rotary, etc. Cable tool construction is desirable because drill cut-
tings are sampled from discrete depths. Well casings may comprise PVC or
steel. Perforations may be installed by a variety of techniques, e.g.,
drilled holes, slots, etc. Well completion may involve using a swedge block
and bailing, and/or pumping. Finally, wells may or may not be gravel packed.
The wells could be used in pumping tests to determine aquifer properties,
T and S. A number of techniques could be used. Those reviewed by Lohman
(1972) include the Theis method and the Jacob straight-line method for con-
fined aquifers, the Hantush modified method for leaking confined aquifers,
and Boulton's method for unconfined aquifers.
The wells could also be used as observation wells. Water levels could
be routinely measured via an electric sounder or chalked tape, or instru-
mented with automatic water-stage recorders.
Preliminary Recommendations--
The following preferred approach is recommended for nonsampling hydro-
geological studies:
• Collect available data on the hydrogeology of both the source
(the sedimentation ponds) area and from the regional system.
• Use available wells to conduct aquifer tests, supplemented by
constructing additional wells as necessary to provide a network
of at least four wells. Ensure that the well network is ar-
ranged such that the potentiometric surface can be defined from
water level data for all aquifers that may be affected by mining.
• One bore hole in the network will be used to install piezometer
clusters within the uppermost aquifers.
39
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• Construct wells via techniques commonly used in the area (i.e.,
either rotary or cable tool). Collect drill cuttings for labor-
atory determination of particle-size distribution. Use PVC
wells, perforated by either drilling holes or by slotting. Gra-
vel pack wells if necessary. Develop wells by pumping and surg-
ing for a sufficient time to reduce turbidity in pumped water.
• Use aquifer testing procedures appropriate to either confined,
unconfined, and/or a leaking aquifer. Determine anisotropic
transmissivity values (if the aquifer is fractured).
The costs of this step, as summarized in Appendix B, Table B-2, would be
highest of the entire program for the sedimentation pond. However, these
costs would be expended only in response to a data set developed from evalua-
tion of infiltration and mobility of pollutants in the vadose zone which in-
dicated a need to monitor pollutant attenuation and migration in the saturated
zone. This information would be developed from previous iterations through
the monitoring methodology and would justify the large expenditures assigned
to the hydrogeologic framework monitoring program. Specific costs for this
monitoring step would include the following:
• Labor costs for:
-- Collecting and evaluating existing hydrogeologic information
-- Overseeing drilling and well construction and development
programs, including collection of drill cuttings
~ Conducting aquifer tests, including collecting, analyzing,
and interpreting data
-- Routinely sounding observation wells and changing charts on
water stage sounders.
• Operating costs will include:
-- Travel (vehicle operation)
— Laboratory costs for determining particle-size analyses of
drill cuttings
-- Miscellaneous costs for materials (e.g., chart paper).
• Capital costs for:
-- Well construction and development
— Well casing
-- Water-level sounder or tape
-- Submersible pump used in pumping tests and portable generator.
40
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Study Existing Groundwater Quality
Activities during this step will overlap related steps involving charac-
terizing the hydrogeologic framework and determining the attenuation of pol-
lutants in the zone of saturation. Impact of groundwater quality is also
closely associated with infiltration rates and migration of fluids through
the vadose zone from the source area.
Monitoring Needs-
Determining the impact of a pollution source on groundwater quality
involves determining time trends in the concentrations of pollutants in up-
gradient and downgradient wells. Ideally, these wells should be relatively
close to the source because of the generally slow flow rates of groundwater.
Alternative Monitoring Approaches--
One nonsampling method would consist of collecting available water qual-
ity data from every available source, including the mining company, the U.S.
Geological Survey, consultants, etc. The interpretations (if any) of these
agencies could be used to estimate the quality impact of seepage from the
sedimentation pond. Alternatively, the raw quality data from monitor wells
near the ponds could be used to construct chemical hydrograms or trilinear
diagrams, and isopleth maps for various constituents. Results could be com-
pared with data on source-pollutant characteristics.
A water sampling program could be initiated to characterize the current
groundwater quality in the vicinity of the source and downstream washes.
Methods include sampling from existing monitor wells, if such wells are near
the ponds, installation of supplemental wells, and a combination of the first
two methods. The second method would require the construction of monitor
wells. Such wells would be constructed during the previous step (define the
hydrogeologic situation). Note that the multiple well, installed during that
step, could be used to sample from different depths in the uppermost aquifer,
and also from different aquifers.
Water samples could be obtained by a variety of alternative techniques:
submersible pumps, hand bailing, airlift pump, etc. The submersible pump
permits redevelopment of the well and rapid sample collection. The latter
feature is desirable in light of the recommendation that at least five casing
volumes be removed prior to sample collection (Mooji and Rovers, 1976).
Wyoming recommends that one to two casing volumes be exchanged. Hand bailing
is a viable method in small-diameter casing. Airlift pumps introduce air
into the sample, causing changes in unstable constituents, such as pH, DO,
and alkalinity.
Three methods of water sample analysis are possible. Samples could be
completely analyzed for constituents listed above (Identify Potential Pollu-
tants) in each of the following categories: major inorganics, trace consti-
tuents, organics, and microorganisms. Alternatively, the first few water
samples could be examined completely. Once the principal constituents are
identified (primarily those occurring in greater-than-permissible levels),
41
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subsequent analyses would be for these constituents only. Note that this
approach should be used only for trace constituents, organics, and microorga-
nisms. The major constituents should be determined completely for each
s amp1e.
A third technique would be to field analyze pH, EC, DO, alkalinity,
chloride, and nitrate. When pronounced changes (i.e., above instrument or
experimental error) occur, a sample could be collected for laboratory
analyses.
Preliminary Recommendations--
The following preferred approach is recommended:
• Examine groundwater samples from available wells and special
wells constructed during the previous step (Define Hydrogeolgic
Framework). Special attention would be paid to sampling from
the multiple-level well.
• Use a submersible pump for sample collection. Pump for a suf-
ficient period of time to remove five casing volumes. Always
carry an alternative sampler (e.g., hand bailer) in case of
failure of the submersible pump.
For all samples, it is recommended that collection, preservation, and
storage be conducted in accordance with recommended methods (Brown, Skougstad
and Fishman, 1970).
The preferred monitoring approach would comprise:
• Completely analyze the first five samples from each well. De-
lineate parameters in excess of recommended limits.
• Field check for such parameters as pH, EC, DO, nitrate, and
chloride. Collect a sample for laboratory analyses when marked
changes occur between field checks.
« Analyze samples collected during the second item for those trace
constituents, organics, and microorganisms delineated during the
first item. All samples would be examined for the entire suite
of major inorganics.
• Always implement appropriate quality control measures (e.g.,
submission of duplicate samples to alternative laboratories).
Samples would be collected on a weekly basis until time trends in qual-
ity are established. Thereafter, samples would be obtained on a bimonthly
basis. Note, however, that unusual events may necessitate a greater sampling
frequency, e.g., the introduction of toxic substances into the pond from pit
discharge.
42
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The principal cost for characterizing groundwater quality would initially
be for sample analyses. Later, as quality trends become apparent, the sam-
pling frequency and analyses would be reduced. The use of field checks to
determine when laboratory analyses are necessary represents a cost-effective
approach. Specific costs are itemized in Appendix B, Table B-2, and include:
• Labor costs for:
-- Collecting, analyzing, and interpreting available water qual-
ity data
-- Collecting, preserving, and storing groundwater samples.
• Capital costs for:
-- Submersible pumps
-- Hand bailer
-- pH meter
-- EC bridge
-- DO meter
-- Field kit for determining chloride and nitrate.
• Operating costs for:
-- Sample analyzer
-- Miscellaneous items, such as sample bottles, thermometers,
chemicals, storage chest, etc.
The capital items listed above are general project tools, available for
the overall TEMPO monitoring program. Note that monitor wells installed to
characterize the hydrogeology of the site would also be used for sampling.
The capital costs were included in the above step (Define Hydrogeologic Situ-
ation.) The analytical costs would be high initially, but would diminish
throughout the sampling program as the list of constituents requiring analy-
ses is narrowed and when field checks are used.
Evaluate Infiltration Potential
Herein, infiltration refers to seepage within the sedimentation ponds
and in the downstream outflow channel during ponds discharge.
Monitoring Needs--
The primary monitoring need is to determine the quantity of water seep-
ing into the subsurface from the sedimentation pond and outflow channel.
43
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Alternative Monitoring Approaches--
Two alternative methods are possible for estimating pond seepage: the
water budget method and a seepage matrix. The water budget method requires
determining inflow rates, from all sources, outflow rates, evaporation-
rainfall rates, and changes in storage. Inflow rates from the pit and pack-
age plant could be determined via weirs or flow meters. Runoff from the
watershed draining into the ponds could be estimated from rainfall data *and
suitable rainfall-runoff relationships, such as developed by Craig and Rankl
(1977). Outflow rates may also be determined via weirs or flow meters. The
amount of water removed from the ponds for road spraying could be estimated
by knowing the capacity and number of truckloads utilized for dust suppres-
sion. Evaporation and rainfall rates may be determined by installing rain
gages and evaporation pans in the vicinity of the pond by using meteorologi-
cal data from an on-site station, or by using such data from a nearby station.
The most cost-effective approach is to use data from an on-site station. Data
from other areas may not be strictly applicable. Changes in storage may be
determined by installing either staff gages or an automatic stage recorder.
The latter unit would require a still ing-well and possibly a platform. Staff
gages offer the most cost-effective approach unless rapid changes in water
levels are expected.
When all the above components of the water budget have been determined,
seepage rates are calculated by differences.
Seepage meters provide point information on seepage. Such meters may be
difficult to install and operate in sedimentation ponds. In addition, a
large number of observations is required in order to ensure that results are
meaningful.
Infiltration in the outflow channel when pond overflow occurs may be
determined by using existing flumes, by installing flumes between measuring
points, or by current metering different reaches.
Water budget determinations may be made on a continuous or intermittent
basis. Continuous determinations would require the installation of recording
flow meters, automatic stage recorders, etc. Alternatively, the measurements
required to compute a water balance could be obtained on a monthly or seasonal
basis. In addition, measurements could be obtained before and after sedimen-
tation removal. The surface mining reclamation and enforcement provisions
require that sediment be removed from sedimentation ponds when the volume of
sediment accumulates to 60 percent of the sediment storage required. After
sediment removal, seepage rates would probably increase.
Preliminary Recommendations--
It is recommended that the water budget approach be used on this proj-
ect. Although the initial cost of seepage rates via a water budget may be
greater than by installing seepage meters, the results would be more accurate.
In addition, capital items (e.g., weirs) may be general project items, reduc-
ing the cost apportioned to the sedimentation ponds. A cost-effective ap-
proach for monitoring infiltration through the outflow channel would be to
44
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utilize existing gaging stations, where possible, supplemented with an addi-
tional station in an upstream or downstream location.
The preferred approach to conducting a water balance for the sedimenta-
tion pond would be to obtain measurements on a monthly basis, until a seepage
curve is obtained, and thereafter on a semiannual basis (e.g., in the winter
or summer). Measurements would also be obtained before and after sediment
removal.
Seepage rates in reaches of the outflow channel would be determined via
an existing or project gaging station on a frequency dependent on pond over-
flow. That is, if overflow is continual, measurements would be obtained on a
monthly basis. If overflow is periodic, measurements would also be periodic.
Note that seepage rates would also be obtained during snowmelt or thunder-
storm runoff.
The principal costs for this effort are given in Appendix B, Table B-2,
and include:
• Labor costs for:
-- Conducting water balance studies on the sedimentation ponds,
i.e., for installing weirs and flow meters
-- Installing staff gages on automatic stage records
— Collecting rainfall-evaporation data (or for installing asso-
ciated equipment)
-- Determining rainfall-runoff relationships for the contribut-
ing watershed
-- Analysis and interpret!on of data
-- Determining seepage in the outflow channel.
• Capital costs for:
Weirs or flow meters
-- Water stage recorders or staff gages
~ Gaging station in the outflow channel.
• Operating funds for travel, chart paper, etc.
The capital items listed above would be general project items, and costs
would be apportioned to usage.
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Evaluate Mobility In the Vadose Zone
Mobility and attenuation of potential pollutants in the vadose zone will
depend entirely on the quantity of infiltration water, defined in the previ-
ous step, which enters the zone. Thus, this and subsequent monitoring steps
will be implemented only when preceding studies indicate a need for further
evaluation.
Monitoring Needs--
Data gaps exist in knowledge of the factors tending to attenuate pollu-
tants within the vadose zone (i.e., dilution, filtration, sorption, chemical
precipitation, buffering, oxidation reduction, volatilization, and biological
degradation and assimilation), and field data on transformations in water-
borne pollutants during flow in the vadose zone.
Alternative Monitoring Approaches--
The potential attenuation of pollutants in the vadose zone may be de-
picted by constructing a matrix (table) comprising attenuating factors (rows)
versus specific pollutants (columns). Each location in the matrix would spe-
cify the relative potential of a factor (e.g., sorption) to attenuate a spe-
cific pollutant (e.g., zinc). Each position in the table may be filled in by
subjective evaluation, or on the basis of actual measurement. Subjective
evaluation would involve examining available data and estimating the effect
on the mobility of a specific pollutant. Alternatively, actual values from
attenuating factors may be obtained from field measurements. For example,
drill cuttings obtained during construction of wells may be analyzed to char-
acterize cation exchange, pH, particle size, Eh, etc.
Obviously, completion of the above matrix would be highly complicated
because of the interaction (synergistic or antagonistic) of several of the
attenuating factors. In addition, some factors may not be easily determined
or estimated (e.g., volatilization). Consequently, the rpcommended approach
is to use a mix of subjective estimates supplemented, when possible, with
actual data.
Access wells could be constructed through the vadose zone. Water con-
tent profiles could thus be obtained using a neutron moisture logger. The
vertical movement of water could be inferred by periodically logging in sin-
gle wells. For example, water content changes between daily logs could be
used to calculate the daily rate of moisture accretion to, or drainage from,
vertical segments of the vadose zone. In addition, the growth and dissipa-
tion of perched groundwater may be manifested on logs. The rate of lateral
movement of perched groundwater could be inferred by monitoring water content
profiles in a transect of wells. Several construction methods are possible
for installing access wells (e.g., rotary percussion, cable tool). However,
the method providing the tightest fit should be selected. Access wells could
be constructed of steel, PVC, or aluminum. PVC would moderate the thermal
neutrons used in moisture detection and result in poor resolution. Aluminum
wells could deteriorate under highly saline conditions.
46
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Water movement in the vadose zone underlying the sedimentation ponds may
also be estimated by installing tensiometers and using methods described by
Bouwer and Jackson (1974). Such units could be installed in several depths
below the sedimentation pond. Tensiometers fail at water pressures less than
-0.8 atmosphere. Alternatively, moisture blocks could be installed. Blocks
function at greater suctions.
In order to characterize water movement beneath the outflow channel dur-
ing pond overflow or natural discharge, access wells and/or tensiometers and
moisture blocks could be installed at two or three locations.
Supplementing the above nonsampling program, field activities could be
initiated to monitor the actual movement of pollutants in the vadose zone.
Alternative methods include: collecting drill or auger samples for labora-
tory analysis, installing suction cups, and installing sampling wells within
perched groundwater bodies.
Collection of samples of vadose zone sediments would entail using hand
or power augers or core samplers. Depending on physical composition of sedi-
ments underlying the ponds, hand-augered samples could be obtained to a depth
of about 10 feet. If deeper samples were required, power equipment would be
needed. Samples may be collected (if possible) within the pond and in a
transect away from the pond. Similarly, hand or power auger samples could be
collected in the outflow channel. Samples could be taken to a laboratory for
analysis.
Suction-cup lysimeters could be installed throughout the vadose zone
provided the region consists of alluvium. Installations of cups in shale or
sandstone might cause post-operational difficulties. Suction cups can be in-
stalled as individual units, in depth-wise increments, or as multiple units
in a common bore hole. The cheapest approach is to install separate units to
a depth of about 5 to 10 feet, say in 1-foot increments. Beyond 10 feet, bore-
hole installation would be a more efficient alternative. For illustration of
suction-cup lysimeter installations and operation procedures, see Fenn et al.
(1975). Note that suction-cup lysimeters become inoperable at a soil water
pressure less than -0.8 atmosphere.
The presence of perched groundwater could be detected from neutron mois-
ture logs. Perched groundwater regions may yield water in sufficient volume
to permit sampling. In this case, PVC wells could be constructed to the
perched regions and samples extracted by hand bailing or by pumping.
Water samples collected from suction-cup lysimeters could be analyzed
completely or partially. Ideally, a complete analysis includes the major
inorganics, trace constituents, and organics listed under Identify Potential
Pollutants. (Note that the ceramic suction cups may filter out microorga-
nisms.) Upon examination of the results of complete analysis, it may be
opted to analyze subsequent samples only for those trace constituents found
present in greater than permissible concentrations. A complete analysis for
major constituents is always recommended.
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Solid samples could be used to obtain saturated extracts via techniques
in Methods of Soil Analysis (Black, 1965). Saturated extracts could be em-
ployed to determine particle-size distribution, cation exchange capacity, EC,
pH, and specific major and trace constituents, including Ca, Mg, K, Na, C02,
HC03 SC>4, Cl, and B. Additional techniques are available for determining
other trace constiuents, such as Cu, Zn, F, Se, Co, and Mo (Black, 1965). Or-
ganics could be determined using procedures described by Dunlap et a!., 1977.
Water samples pumped from PVC wells within perched layers could be ana-
lyzed using alternatives described under Study Existing Groundwater Quality.
These alternatives include: complete analysis of each sample; complete
analysis of the first five to ten samples, until the water quality is char-
acterized; partial analysis for those constituents found in excessive con-
centrations; and field checks.
Sampling frequency in suction-cup lysimeters depends on the water pres-
sure within the surrounding porous matrix. Thus, if the system is very dry,
water will enter the cups at a very slow rate. A week or more may be required
before sufficient sample is available for analyses. In the extreme case, the
cups may become inoperable (i.e., when water pressure is less than -0.8 at-
mosphere). In this case, samples may become available only once or twice a
year. In contrast, if the porous system is very wet, samples may be extracted
on a daily basis. In other words, the sampling frequency cannot be explicitly
defined until field units are installed and operating. For a wet system, it
may be desirable to collect samples on a more frequent (e.g., weekly) basis
until quality trends are established. Later, samples could be obtained once
a month.
Perched groundwater may be available only on a cyclic basis. Samples
would then be obtained whenever possible. If perched groundwater is avail-
able continuously, samples could be obtained frequently (say, once a week)
until quality trends are established. Later, samples could be collected on a
monthly basis.
Preliminary Recommendations--
The preferred approach for estimating pollutant movement in the vadose
zone would comprise:
• Construct a matrix of attenuation factors versus specific pollu-
tants using available data when possible, supplemented with
intuition.
• Install three access wells laterally away from the sedimentation
ponds, into the uppermost aquifer.
• Install two networks of shallow tensiometers and moisture blocks
in each pond with individual units terminating in foot incre-
ments to 5 feet beneath the base of the ponds.
• Install a network of shallow access wells, tensiometers, and
moisture blocks at three locations along the outflow channel.
48
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6 Install suction-cup lysimeters in 1-foot increments to a depth
of 10 feet below the base of the pond and in the outflow channel
alluvium. Three sets of suction-cup lysimeters would be in-
stalled, one set within or immediately next to the pond, and the
remaining sets at intervals along the outflow channel to be de-
termined later. If suction-cup samples show that deep percola-
tion of water is occurring, additional units would be installed
at greater depths.
• During installation of suction cup lysimeters and PVC wells,
collect solid samples for laboratory analysis of pollutants.
« Collect additional auger samples of solids only as deemed neces-
sary, or when suction cups are inoperable.
• Install one PVC well within each perched groundwater body de-
tected by neutron logging and sample via a submersible pump.
A preferred approach for analyzing solid and water samples collected
from the vadose zone would comprise:
• Analyze solid samples for major and trace constituents and or-
ganics. Particular attention would be paid to determining those
pollutants found in excessive concentrations in the source dur-
ing the program, Identify Potential Pollutants.
• Analyze the initial five to ten water samples from the suction-
cup lysimeters completely for major trace constituents. Subse-
quently, completely analyze for major constituents, but only for
those trace constituents found in excessive concentrations.
• Examine perched groundwater samples completely for major and
trace constituents, organics, and microorganisms in the first
five samples. Subsequently, only those trace constituents,
organics, and microorganisms found in excessive concentrations
would be determined. After the initial characterization, field
checks would be made of pH, EC, chloride, and nitrate. When
substantial changes occur in these constituents, samples would
be collected for partial analysis, as described above.
A preferred approach to sampling frequency would be:
• Sample suction cups whenever possible during very dry condi-
tions. For wet conditions, sample weekly until quality trends
are established. Thereafter, sample once a month.
• Obtain and analyze solid samples only during installation of
suction cups and PVC wells
• Sample PVC wells at a frequency depending upon availability of
free, perched groundwater.
49
-------
Costs associated with the recommended approach for monitoring in the
vadose zone are summarized in Appendix B, Table B-2, and include:
• Labor costs would be broken down into the following items:
— Constructing an attenuation factor versus pollutant matrix
and interpreting results
-- Overseeing the installation of access wells, and subsequently
logging the wells
-- Installing tensiometers and moisture blocks and collecting
and interpreting results
-- Obtaining and examining data from neutron moisture logs and
tensiometer data to determine the flux of water (and pollu-
tants) in the vadose zone
-- Installing suction-cup lysimeters
-- Collecting solid samples from the vadose zone
— Collecting water samples from the suction cups and PVC wells
(if constructed)
— Conducting field checks on pH, EC, chloride, and nitrate.
« Capital costs would include:
-- Access wells
-- Neutron moisture logger
-- Tensiometers
-- Suction-cup lysimeters
— PVC wells
-- pH meter, EC bridge, and field kit for measuring chloride and
nitrate; these items are general project items and associated
costs for this step will be apportioned according to usage
-- Hand augers or power augers; again, these would be project
items.
• Operating costs would comprise:
-- Analytical costs for water samples. This cost would be re-
duced when field checks are used to determine the need for
laboratory analysis. Also, the number of requisite analyses
would be reduced throughout the program.
50
-------
-- Analytical costs for analysis of auger samples.
-- Transportation costs, sample bottles, etc.
Evaluate Attenuation of Pollutants in the Saturated Zone
As pointed out by Todd et al. (1976), the principal processes involved
in attenuating pollutants in the zone of saturation include: decay, physical-
chemical reactions, or dilution. For pollutants in a source, such as a sed-
imentation pond, physical-chemical processes and dilution may be of prime
significance. Included in the physical-chemical processes are sorption, pre-
cipitation, volatilization, oxidation-reduction reactions, etc. Dilution is
effected by hydrodynamic dispersion resulting from such effects as convection
diffusion, and flow tortuousity.
At the present time, dispersion (or dispersiyity) within an aquifer is
difficult to determine without careful, extensive' field experimentation. A
qualitative notion of dilution resulting from dispersion may be obtained from
knowledge of the following (see Todd et al., 1976): volume of wastewater
reaching the water table, the waste loading, areal head distribution, trans-
mi ssivity values, vertical hydraulic-head gradients and permeabilities,
groundwater quality, quantity and quality of recharge from other sources, and
pumpage volumes and patterns.
Monitoring Needs--
Information gaps currently exist in predicting the effect of the follow-
ing mechanisms on pollutant attenuation within aquifers underlying the sedi-
mentation pond: physical-chemical reactions and dilution.
Alternative Monitoring Approaches—
The relative effect of various physical-chemical mechanisms for attenua-
tion pollutants within the saturated zone could be estimated by constructing
a matrix similar to that for the vadose zone. That is, a table could be pre-
pared consisting of attenuating mechanisms (rows) versus pollutants (columns).
Attenuating mechanisms would consist of the following physical-chemical fac-
tors: sorption, precipitation, volatilization, oxidation-reduction (Eh),
decay, and dilution. When completed, the table would show in a mixed
qualitative-quantitative sense the pollutants which should be monitored.
Completion of the matrix for the physical-chemical items requires speci-
fic information on exchange capacity of aquifer materials, on the Eh and pH
of groundwater, as well as on the specific pollutants entering the zone of
saturation. Many of the physical-chemical parameters could be quantified
from analysis of drill cuttings obtained during well construction (see Define
Hydrogeologic Situation), and from field analysis of Eh and pH. Identifica-
tion of pollutants must await the results of mobility studies in the vadose
zone.
Estimating the effect of dilution on pollutant attenuation would require
data on items listed previously, i.e., volume of wastewater reaching the
51
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water table, the waste loading, area! head distribution, aquifer transmissiv-
ity, vertical hydraulic head gradients and permeabilities, groundwater qual-
ity, quantity and quality of recharge from other sources, and pumpage volume
and patterns. The volume of pond water reaching the water table may be esti-
mated from data on seepage rates (see Evaluate Infiltration Potential). As-
sumptions are that steady-state seepage has been reached and that the water
content of vadose sediments equals or exceeds field capacity. Water content
data from access wells installed earlier would be useful in verifying these
assumptions. Similarly, neutron moisture logging data in a transect of ac-
cess wells may indicate the lateral spread of pond water within the vadose
zone and, consequently, the waste loading rate. It might be necessary to
install additional access wells to obtain adequate resolution. Areal head
distributions in the aquifer could be obtained via the set of four wells
installed earlier (Define Hydrogeologic Situation). Similarly, piezometer
clusters may provide data on vertical hydraulic gradients, and possibly on
vertical hydraulic conductivity. Aquifer transmissivity values may also be
obtained as a result of earlier pumping tests on the four wells. Groundwater
quality could be quantified as a result of activities during the step, Study
Existing Groundwater Quality. The quantity and quality of recharge from
other sources could be the most difficult items to identify. Available data
would be used if possible, e.g., on seepage rates in the outflow channel.
Similarly, information on pumping rates in existing wells would be solicited
from the mine manager.
In lieu of constructing an attenuation matrix, an alternative method
would entail initiating tracer studies to estimate the spread and attenuation
of pollutants. For example, a conservative tracer, such as chloride, could
be injected in one of the upstream wells installed earlier and water samples
extracted periodically from downstream wells. However, in light of possible
low T values in the shallow aquifers, the time to obtain a tracer breakthrough
in downstream wells could be excessive.
Groundwater samples could be obtained for analysis and ensuing data
examined to characterize pollutant attenuation. The network of four wells
installed during previous steps could be used in such a program. In actual-
ity, a special sampling program would not be required, because samples would
be available from these steps.
It is imperative that vertical samples be obtained within the water-
bearing strata being examined. The rationale for this necessity was stated
by Mooji and Rovers (1976).
In the past it was frequently assumed that the monitoring of the
upper few feet of an aquifer was adequate as it was assumed that
the contaminants migrated vertically to the water table followed
by lateral migration in the upper zone of the aquifer. In fact,
recent research studies show that the contaminants can migrate to
the bottom of the aquifer prior to extensive lateral migration
taking place . . . . Therefore the preferred method is to install
piezometers at varying depths throughout the thickness of the
aquifer.
52
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In lieu of, or to supplement, piezometer clusters, alternative methods
for obtaining depth-wise samples from a given water-bearing formation include
multilevel samples and groundwater profile samplers. Details of a multilevel
sampling well designed by Pickens et al. (1977) are illustrated in Figure 4.
This well consists of PVC or steel well casing, ports or openings at desired
incremental depths, screened coverings on openings, and polypropane tubing
sealed onto the openings, extending to the surface. According to Pickens
et al. (1977), this unit may be used to depths of 30 to 40 meters. The ad-
vantages of this unit are that depth-wise sampling is facilitated and overall
construction costs may be lower than for piezometers. A suitable pumping
unit may be such as that used to purge tensiometer units (available from Soil
Moisture Equipment Company, Santa Barbara, California).
An alternative depth-wise sampler was designed by Hansen and Harris
(1974). The unit, called a "groundwater profile sampler," is shown in Fig-
ure 5. Basically, the sampler consists of a 1%-inch diameter well point, of
optional length, with isolated chambers containing fiberglass probes. The
individual chambers are filled with sand and separated by caulking compound.
Small-diameter tubing provides surface access to the probes. The positioning
of probes is optional, depending on aquifer materials, desired sampling fre-
quency, etc. In operation, a vacuum is applied to the lines pulling the
sampling flasks. Hansen and Harris (1974) recommended that all samples should
be extracted simultaneously and at the same rate to minimize variation in
aquifer thickness sampled by the individual probes. Water tables as deep as
30 feet may be sampled by the unit (Hansen and Harris, 1974).
Preliminary Recommendations--
A preferred monitoring approach includes:
• Construct an attenuating mechanism versus pollutant matrix, us-
ing available data whenever possible
• Conduct tracer studies if two monitor wells are deemed to be
sufficiently close that short-time studies are possible
• Use monitor wells installed during previous steps and install
additional piezometer clusters as necessary to obtain samples
for characterizing the vertical distribution of quality. (The
other methods, multilevel samplers or groundwater profile sam-
plers, are not recommended unless the water table is very
shallow.
The costs for the proposed approach are summarized in Appendix B,
Table B-2, and would consist of:
• Labor costs for obtaining data necessary to prepare and inter-
pret the attenuation mechanisms versus pollutant matrix. Labor
costs for collecting water samples would be accounted for under
Study Existing Groundwater Quality.
• Capital costs for additional wells.
53
-------
Figure 4. Multilevel groundwater sampler (after Pickens et al., 1977).
MULTI-LEVEL GROUNDWATER SAMPLER
FIELD INSTALLATION
CROSS-SECTION OF SAMPLING POINT -TYPE A
CROSS-SECTION OF SAMPLING POINT -TYPE B
END CAPp
WATER TABLE
PVC SAMPLER
PIPE
COUPLING
SAMPLING
POINTS
PVC PIPE
-SCREEN
FIBERGLASS
CLOTH
END CAP
-------
,1/4" OD TUBING
1/4"CAULKING-
HOLES
1 1/4" WELL POINT-
SAMPLE COLLECTION
FLASKS
FIBERGLASS-
SAND MATRIX-
PROBE
Figure 5. Groundwater profile sampler (after: Hansen and Harris, 1974)
55
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• Operating costs for analyzing water samples would be accounted
for in the step, Study Existing Groundwater Quality.
EXAMPLE CASE STUDY—SUN OIL COMPANY'S CORDERO MINE
The following case study is derived from data compiled on an active mine
water source (sedimentation ponds) for Sun Oil Company's Cordero Mine.
Identify Potential Pollutants
The Cordero Mining Co. (1976) states that two settling ponds combined in
series are designed to receive runoff of source water from the facility area,
sewage treatment plant effluent, pit water, and runoff from a 2.8-inch rain-
fall in a 24-hour period (i.e., 50-year flood). The ponds that typically
impound less than 20 acre-feet of water will retain the source waters for ap-
proximately 5 days as required by the Wyoming Department of Environmental
Quality to settle out suspended solids. The water will meet the other efflu-
ent standards, such as pH, iron, manganese, and total suspended solids as
well as applicable Wyoming water qualfty standards. Under normal operating
conditions, no discharges are expected from the ponds. However, a sand fil-
ter is installed on the second settling pond as a final step in removing any
suspended solids. The sedimentation ponds are located in T47N, R71W, S29
(see Figure 6). Note the locations of a sewage treatment plant (package
plant) and a proposed supplemental sedimentation pond.
Potential pollutants in the pond water have not been characterized. For
a general discussion of pollutants likely to occur in the source waters, see
Everett (1979).
Water-borne pollutants in the sedimentation ponds could represent a
threat to local groundwater quality should leakage occur. As shown on Fig-
ure 6, the sedimentation ponds are located on the floodplain of the Belle
Fourche River and, therefore, overflow from the ponds could introduce pollu-
tants into alluvial aquifers underlying the Belle Fourche River.
According to the Cordero Mining Company (1976), the pond water will meet
Wyoming quality standards for suspended solids, pH, iron, manganese, and
other (unspecified) water quality standards and no overflow is expected under
normal operating conditions. In addition, it is stated that "... the qual-
ity of the water will be monitored." In the event that pond overflow occurs,
the standards in the NPDES permit must be fulfilled, again requiring monitor-
ing. Note that except for suspended solids, pH, iron, and manganese, speci-
fic parameters to be characterized are not specified.
Define Groundwater Usage
The water table at the site is apparently near the middle of the coal
seam. During mining, the pit water is to be pumped into two settling basins
capable of holding water from 6 days of normal mine discharge. The water in
the settling basins will be used primarily for dust control. The U.S. Geo-
logical Survey (1976) states that any discharge to the Belle Fourche River
will be minimal. However, an NPDES discharge permit has been obtained. Pit
56
-------
(SUN OIL) CORDERO LEASE AREA
Figure 6. Location of sedimentation pond.
57
-------
water will come primarily from seepage from the coal aquifer, and secondarily
from limited groundwater in the overburden and spoils. Near the Belle Fourche
River in the southern part of the site, a substantial portion of the pit dis-
charge may come from percolation of surface water through alluvium. The rate
of pit discharge has been estimated to range from 40,000 to 100,000 gpd, and
average 70,000 gpd. Groundwater from strata beneath the coal may move upward
into the pit during mining.
Surface water runoff will generally be kept from the pit by diversion
ditches. To prevent water from the Belle Fourche River from entering the
pits, some of the oxbow loops have been eliminated by construction of a new
river channel across the heads of the loops.
Mining plans for the Cordero Mine (Sun Oil Co., 1976) indicate that
groundwater will be pumped to supply potable water needs of the mine. Pumped
water will be stored in a 20,000-galIon tank. Usage is expected to amount to
15,000 gpd. (Note: water for the sedimentation ponds, including package
plant effluent, will be used for firefighting and other plant needs.)
A facility layout included in the mine plans (Cordero Mining Company,
1976) shows the location of two water wells in T47N, R71W, S24, and a wind-
mill in T47N, R71W, S23. Reference is also made to the Hayden well, possibly
a domestic well near the mine.
Although the locations of wells appear to be well defined on the Cordero
mine, data deficiencies exist in the following: volume of groundwater pumped
for shop, sanitary, and office needs and for fire protection; volume of
groundwater in excess of pit water used for coal preparation; and volume of
groundwater in excess of pit water used for irrigation.
Define Hydrogeologic Situation
Information on the hydrogeologic framework of the Cordero Mine was sum-
marized in a report edited by Everett (1979).
Groundwater exists in the Wasatch Formation, the coal beds, the
alluviated areas of the Belle Fourche River, and probably in the
scoria .... Field observations at the Cordero indicate that
the overburden is generally dry, with the exception of several
lenticular sandstone beds.
The location of the settling ponds on the floodplain of the Belle Fourche
River suggests that they may be underlain by an alluvial aquifer. The extent
of current studies by the Cordero Mining Company to characterize the hydro-
geology of the lease to date is unknown. The Company has not published pump
test results to assist in evaluating the properties of the aquifer's systems.
Eleven wells were constructed on the lease in late 1974 (Cordero Mining Com-
pany, 1976). Static water levels are routinely measured in these wells, and
ostensibly the wells could be used for pumping tests.
Until detailed results of hydrogeologic studies on the Cordero Mine be-
came available, it is presumed that information deficiencies may exist. In
58
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particular, the following data gaps may exist relative to the area encompass-
ing the sedimentation ponds: vadose zone properties (geology, lithology,
etc.), and saturated zone properties, including locations of aquifers and
associated geology and hydraulic head distributions, transmissivities (in-
cluding anisotropic T) and storage coefficients of aquifers, and direction
and velocities of groundwater flow.
Study Existing Groundwater Quality
Although Cordero has been shipping coal since March 1977, its ground-
water monitoring program is not well developed. In its mining plan update
(Cordero Mining Company, 1976). Cordero officials indicated the existence of
only four groundwater quality monitoring stations. These include three water
wells and one stock well. All are Wasatch Formation wells. Quality values
for these wells are shown on Tables 6 and 7.
Cordero reported that these samples show stable values that that they
are useable data. However, the stock well sample was not a pumped sample and
no field sampling techniques were discussed. Also, the Hayden well is less
than 1000 feet from a major tributary to the Belle Fourche River. The low
quantity of dissolved solids in the water is probably due to hydraulic con-
nection with low TDS surface water.
In summary, it appears that monitoring wells on the Cordero Mine are
being used to a minimal extent to characterize the regional groundwater qual-
ity. Specific monitoring for groundwater quality near the sedimentation pond
appears to be minimal or nonexistent at this time.
Data deficiencies exist in the following: current area! distribution of
groundwater quality in the vicinity of the sedimentation ponds, time trends
in the quality of groundwater beneath the ponds, and vertical distribution of
water quality within the uppermost aquifer and differences between adjoining
aquifers.
Evaluate Infiltration Potential
The extent that seepage losses in the ponds and downstream river bed are
being determined by tjne Cordero Mining Company is unknown. Presumably, such
determinations have been minimi a! in the past. At the present time, it ap-
pears that the following data deficiencies exist: seepage losses in the sed-
imentation ponds, and seepage losses in the Belle Fourche River during
overflow.
Evaluate Mobility in the Vadose Zone
Pollutant mobility in the vadose zone underlying the sedimentation ponds
or Belle Fourche River is currently not being monitored on the Cordero Mine.
Evaluate Attenuation of Pollutants in the Saturated Zone
Activities by the Cordero Mining Company to determine the attenuation of
pollutants originating from the sedimentation pond during groundwater flow
59
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TABLE 6. GROUNDWATER QUALITY, HAYDEN RESIDENCE, SUN OIL
CORDERO LEASE (SUN OIL, 1976)
Date
Constituent (mg/1)
Total dissolved solids
Suspended sol Ids
Hardness
Bicarbonate
as HC03
as CaC03
Carbonate
as C03
- as CaCO,
Sulfate
Chloride
Nitrate
Fluoride
Sodium
Calcium
Iron
Lithium
Arsenic
Selenium
Boron
Zinc
Mercury (ug/l)
Cadmium (yg/l)
Copper
Lead
Chromium
Molybdenum
Nickel
Aluminum
PH
field
lab
Alkalinity as CaCOj
September 3, 1974 November 25, 1974
328 360
6
'44 45
377
316
0
<1
<5 3
7 9
1.5 2.9
1.5 1.0
118 133
10
0.24
0.01
<0.01
0.011
0.11
0.14
<0.5
<5
-
-
7.9 7.8
309
February 9, 1975 May 22, 1975
390 354
-
47 85
-
330 415
-
0 0
<1 4
10 18
1.6 1.5
1.9 1.1
150 122
0.05
0.04
0.00
0.00
0.00
0.03
0.000
0
0.00
0.00
0.00
0.00
0.00
0.0
7.50
B.I
-
60
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TABLE 7. GROUNDWATER QUALITY, WELL NUMBER 11, SUN OIL
CORDERO LEASE (SUN OIL CO., 1976)
Date
Constituent (mg/1 )
Total dissolved solids
Suspended solids
Hardness
Bicarbonate
as HC03
as CaC03
Carbonate
as C03
as CaC03
Sulfate
Chloride
Nitrate
Fluoride
Sodium
Calcium
Iron
Lithium
Arsenic
Selenium
Boron
Zinc
Mercury
Cadmi urn
Copper
Lead
Chromium
Molybdenum
Nickel
Aluminum
PH
field
lab
Alkalinity as CaC03
November 25, 1974 February 9, 1975 May 22, 1975a
(a) 2,000 2,160
(a) 920 925
412 770 1,010
0 00
900 910 959
8 12 19
13.2 0.90 0.7
0.58 0.53 0.48
415 440 321
56
0.028 0.03
0.10
0.00
0.00
0.14 0.01
0.00
0.000
0.00
0.00
0.00
0.00
0.00
0.04
0.00
7.6
8.1 7.9
337
aSample not sufficient to analyze.
61
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are nonexistent. As pointed out earlier, 11 monitor wells have been installed
on the lease. However, none of these wells is close enough to the source to
constitute source-specific monitoring wells.
62
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SECTION 4
MONITORING DESIGN FOR MISCELLANEOUS
ACTIVE MINE SOURCES
GENERAL CASE CONSIDERATIONS
Identify Potential Pollutants—Explosives
Mining sites with well consolidated overburden and coal seams utilize
explosives to dislodge the materials prior to their removal. The principal
explosive being used at the mines for blasting is an ammonium-nitrate—fuel
oil mixture known as ANFO. Apparently, the water pollution potential of ex-
plosives used for strip mining has not been studied in detail in the Western
United States. In the case of an incomplete explosion, some ammonium-nitrate
and fuel oil residual will occur. Also, spillage of the explosives could
create a pollution potential. Such materials could directly affect the qual-
ity of pit water. Also, stockpile and spoils could contain these materials
and affect groundwater quality.
Monitoring Needs-
Records of blasting operations in the study area are unknown and it is
therefore assumed that no direct monitoring of explosives in relation to
water pollution potential is performed. There is a need to determine the
approximate amounts of residual ammonium-nitrate and fuel oil from explo-
sives. Spills of these materials should also be monitored.
Alternative Monitoring Approaches—
A nonsampling method of monitoring this potential pollutant source would
utilize much of the required information available in response to the provi-
sions of the Surface Mining Control and Reclamation Act. Specifically, the
location, dates and time of blasting, the type of material blasted, the num-
ber of holes and spacing, the depth and diameter of holes, and the type and
weight of explosives used are to be recorded. From this information, maps
could be prepared illustrating patterns in the use of explosives, such as
hole density or tonnage of explosives. Records should also be maintained on
location and amounts of spills of explosives and cleanup measures, if any.
Sampling of both overburden and coal could be performed prior to and
after blasting. Although the blasted materials are eventually removed from
the area, water could contact the materials and drain into the pit prior to
its removal. Also, after the overburden is removed and prior to blasting of
the coal, the uppermost layers of coal could be sampled for explosives or
63
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residual materials. After the coal is removed, the uppermost layers of under-
burden could be sampled for explosives or residual materials. Water could
run over both of these surfaces and pick up potential pollutants.
Because the explosives are used in close proximity to the pit water body,
sampling of water in the pit and tributary to the pit is recommended. In
general, the direction of groundwater movement in the coal and overburden in
areas where explosives are used would be toward the pit water body. Water
could pick up residuals from explosives or spilled materials during flow over
the surface of the pit. Based on present data, this is the most likely mech-
anism whereby pollutants from explosives would enter the pit water. Thus,
the optimal situation is to monitor explosion residuals and pit water at the
same mine, a procedure followed in this monitoring program design. Monitor-
ing water quality in wells completed in "blasted" and replaced spoils will be
discussed in a subsequent report dealing with reclaimed mine potential sources
of pollution. Water flowing across the pit a significant distance before
entering the pit water body could be sampled along the flow path. At the
same time, samples of solid materials beneath the flowing water could be
sampled for residuals or spilled explosives. If any pollutant transport by
groundwater was occurring, the recommended monitoring for groundwater seepage
into the pit water (see Section 3) would detect it.
Analyses for explosives and residuals can apparently be limited to the
nitrogen forms, fuel oil, and possibly total organic carbon. However, future
studies may show the presence of pollutants unknown at present, but formed as
residuals. If the inventory of type of explosive indicates that additional
potential pollutants are present, then they would also be determined in the
water analyses. For solid materials, saturation extract can be utilized for
chemical determinations.
Samples of overburden and coal should initially be collected on a weekly
basis for determination of explosives and residuals. When water is running
over the surface of the pit and into the pit water body,, monthly traverses
should be made along the flow path. Both the water and the underlying mate-
rials should be sampled.
Preliminary Recommendations--
The nonsampling monitoring alternatives described above are recommended.
Analysis of pit water, described in Section 3, would indicate if further sam-
pling of potential pollutants from explosives would be required.
Costs for the nonsampling method would include labor for inventorying
mining records. Should further sampling be required, additional labor for
field sampling and analytical work would accrue. These costs are summarized
in Appendix B, Table B-3.
Identify Potential Pollutants—Mine Solid Wastes
Solid waste materials are produced during the construction phase of the
mine and to a lesser degree throughout the life of the mine. Four methods
exist to dispose of these wastes. One option is on-site landfills which can
64
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consist of an open dump or a sanitary landfill where the waste is disposed in
great density and covered daily with soil. A second option is off-site dis-
posal --some of the mines have reportedly disposed of premining construction
wastes at a nearby city landfill. A third option is incorporation of wastes
in the mine spoils. This tends to be haphazard and makes source monitoring
difficult; nevertheless, most of the mines are licensed as landfills and this
appears to be the principal means of disposal. A fourth option, which may be
used to varying degrees, is incineration. The ash is buried in the mine,
although some is dispersed through the air to surrounding areas. Potential
pollutants are primarily the organic and inorganic chemicals and trace ele-
ments; secondary pollutants are heavy metals.
The physical environment of the wastes incorporated in these alternative
disposal methods is similar to stockpiles discussed in Section 2. However,
they differ in materials, e.g., scrap lumber, paper, metals, cement, etc., in
addition to overburden or topsoil used to cover the deposits. It is estimated
that an average of one-half cubic yard of solid wastes will be produced per
day.
Monitoring Needs--
The extent of monitoring solid waste disposal areas is unknown. Data
deficiencies are assumed to exist in the characterization of pollutants in
the following categories: major inorganics, trace contaminants (especially
heavy metals) organics, and microorganisms.
Alternate Monitoring Approaches--
A nonsampling method for identifying potential pollutants would be to
estimate quantities and inventory wastes as they are delivered to the dispo-
sal site. The type of wastes entering a landfill is a major determinant of
potential groundwater pollutants. The inventory could be made by stationing
an inspector at the site, or estimating waste from mine construction materi-
als. Spot checks could be done on an infrequent basis.
Potential pollutants would be concentrated in the disposal site leachate
before percolating into the vadose zone. Alternative methods of sampling
leachate would be to install a manifold sampling device or have a bulldozer
dig to the base of the wastes and have grab samples of the leachate taken.
Samples could be taken from suction-cup lysimeters in the vadose zone
and from wells in perched layers and the saturated zone. These would be in-
stalled primarily for use in determining mobility and pollutant attenuation
in the unsaturated and saturated zones.
Grab samples could be taken of surface runoff entering the landfill.
This is a likely source of water for leachate formation. Similarly, grab
samples could be obtained of water found discharging into the landfill.
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Preliminary Recommendations--
The preferred monitoring approach would be to estimate quantities and
type of solid waste from the mine construction materials. The disposal area
could be spot checked at infrequent intervals. Grab samples could be taken
after precipitation events. Suction-cup lysimeters and wells installed for
use during parallel or subsequent monitoring steps could be used to sample
the vadose zone, perched water tables, and the saturated zone near the dis-
posal area.
The first few samples would be analyzed for major inorganics, trace con-
taminants, organics, and microorganisms as described in Section 3 (Identify
Potential Polluants--Sedimentation Ponds), until pollutants are defined.
Thereafter, partial analysis would focus on identified pollutants.
Sampling frequency of the suction-cup lysimeters and wells would follow
data gathering schedules for monitoring steps described in Section 3. Sur-
face runoff grab samples would follow weather patterns.
Costs for identifying potential pollutants from mine solid waste mate-
rial would include labor for intentorying mine construction waste, infrequent
checks of the disposal sites, and collection of field samples. Costs for
analytical work would be covered under alternate monitoring steps except for
a few grab samples of surface discharges from the disposal site. These costs
are summarized in Appendix B, Table B-3.
Identify Potential Pollutants—Liquid Shop Waste
Liquid shop wastes include fluids, such as oils and lubricants, which
are used in the repair and maintenance of mining equipment, and soaps and
wash water used for cleaning trucks and machinery. Waste oils are probably
stored either for recycling or disposal away from the lease area. Other
waste products and water may enter some type of a sewer system where oil/
water separators are usually employed. Water from equipment washing will
probably run onto the ground in a designated equipment-washing area and may
be routed to a sedimentation pond with oil and grease skimmers.
Monitoring Needs--
A need exists to determine the amount of potential pollutants in liquid
soap wastes. Oils, lubricants, gasoline, wash water, soap, and other sub-
stances that may be mixed with these fluids will constitute the primary
sources of these pollutants. Disposal methods for these wastes are unknown.
Alternative Monitoring Approaches--
Several nonsampling methods are available for identifying potential
pollutants: hold discussions with mine personnel on types and quantities of
liquid wastes produced, quantity of waste water used, location of washing
areas, use of soaps, etc. —all of the above can be confirmed through field
observation; quantities of liquid wastes and wash water used can be measured;
an inventory of wastes can be kept on a continuous basis.
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There are several alternative sampling methods for identifying potential
pollutants. The wastes themselves could be sampled and analyzed completely.
Suction-cup lysimeters could be installed in the vadose zone beneath the shop
area and sampled for potential pollutants. Wells could be installed in
perched layers and sampled. Piezometer clusters could be installed for sam-
pling from the saturated zone.
Wells and suction-cup lysimeters should only be installed where they
will be useful in subsequent steps of the monitoring program.
Preliminary Recommendations--
A nonsampling method incorporating discussions with mine personnel to
determine type and quantity of liquid waste produced and field observations
would be recommended. Grab samples of liquid wastes could be taken if deemed
necessary during field checks. These samples would be analyzed for major
inorganics, trace contaminants, organics, and microorganisms as described in
Section 3. Sampling frequency would be determined by field studies.
Costs would include labor for conducting interviews, making field obser-
vations, and collecting grab samples as necessary. Operational costs would
include sampling hardware, bottles, storage racks, etc. These costs are sum-
marized in Appendix B, Table B-3.
Identify Potential Pollutants—Spills and Leaks
Mining operations require the movement and storage of a large number of
substances, any of which can be spilled or leaked from their containers.
Gasoline, diesel fuel, oils, and lubricants are used in the shop area.
Ammonium-nitrate and fuel oil are used for blasting. Herbicides are used to
clear rights-of-way and pesticides; fertilizers and soil amendments are used
in reclamation. Topsoil, overburden, parting materials, and coaly waste are
transported to stockpiles, and, of course, coal is transported from the mine
pit to storage silos or barns.
Monitoring Needs-
Monitoring needs include characterizing types of substances transported
and stored on the lease area and the quantities of these substances. The
monitoring for potential pollutants in spills and leaks of an active mine is
unknown.
Alternate Monitoring Approaches--
Nonsampling monitoring methods include determination of substances
transported and stored at the mine through discussions with mine personnel
and field observation. A review of accident records or past spills would
indicate potential problem areas that could be watched more closely. Grab
samples could be taken if field monitoring personnel are present at a spill
or discover a leak; however, these analyses would be required of substances
for which existing analyses are not available.
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Preliminary Recommendation--
The nonsampling method described for liquid shop wastes is recommended
for monitoring spills and leaks.
Labor for conducting interviews with mine personnel, reviewing accident
or spillage records, and followup field observations are the only cost likely
to accrue from this monitoring step. These costs are given in Appendix B,
Table B-3.
Identify Potential Pollutants—Solid Waste for Road Construction
Access and haul roads to the mines in the study area are constructed
across a variety of surface materials including coal, topsoil, or reclaimed
mine spoils. Roadbeds are often constructed of overburden, and most roads
are surfaced with scoria, when it is available. Pit water is applied to the
roads on a continuous basis to reduce airborne dust. In addition, Coherex,
an oil-water emulsion of petroluem resins, can be mixed with the pit water
and applied about once a month to control dust. The extent to which roads
may constitute a pollution source is dependent upon construction materials,
the quality and quantity of water which comes into contact with the road
surface, and the total land area covered by roads.
Monitoring Needs-
Monitoring needs for potential pollutants in road construction materials
include major inorganics and trace constitutents leached from these materials
and the quality and chemical additives of the water used to control road dust.
With the exception of chemical additives, potential pollutants from road con-
struction materials are described elsewhere in this report. The aerial dis-
tribution and potential for interaction through surface runoff with local
drainage systems are important factors in including these materials as a sep-
arate miscellaneous source of potential pollutants.
Alternate Monitoring Approaches--
Interviewing mine personnel to determine mine road construction materi-
als and dust suppression programs would provide the required information for
a nonsampling monitoring method. Potential pollutants found in the construc-
tion materials, overburden or mine spoils, and pit water used for dust sup-
pression are discussed in Sections 2 and 3, respectively.
Preliminary Recommendations—
The nonsampling monitoring method is recommended to determine location
of roads, construction materials, and dust suppression programs. Chemical
constituents of the mine road solid wastes will be characterized in parallel
or subsequent monitoring steps.
Labor costs for conducting interviews with mine personnel and transpor-
tation for field checks would be the only expense for this monitoring step.
These costs are summarized in Appendix B, Table B-3.
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Identify Potential Pollutants—Septic Tanks
The principal function of a septic tank is to permit settling of solids,
flotation of grease, anaerobic stabilization of organic matter, and storage
of sludge (Hammer, 1977). The majority of the biological treatment occurs in
the leaching field.
Specific pollutants in the specific tank and leach field will primarily
be of sanitary origin. However, water (carrier of the wastes) may contain
constituents concentrated during usage. Principal among these constituents
are the major inorganics (e.g., calcium, magnesium, potassium, sodium, bicar-
bonate, chloride, and sulfate) and trace contaminants (e.g., iron, manganese,
zinc, copper). Organics include stabilized and unstabilized organics, grease,
and oils. Microorganisms may include bacteria (e.g., total and fecal coli-
form, fecal streptococcus, and viruses).
Monitoring Needs--
Presumably, the operation of the septic tank may be checked periodically
and possibly samples are taken for analysis. Similarly, the leach field may
be checked occasionally to ensure that soil clogging is not occurring.
Until specific data are obtained, it is assumed that data deficiencies
exist in monitoring for specific pollutants outlined above.
Alternative Monitoring Approaches--
A nonsampling method leading to a characterization of pollutants in sep-
tic tanks and leaching fields is to inventory all sources discharging to the
septic tank and estimate their relative quantities. For example, in addition
to sanitary wastes, certain shop wastes (possibly including toxic substances)
may occasionally be flushed into the system. The number of individuals using
the system could also be identified. Engineering plans for the system, show-
ing the size of the septic tanks, distribution of sewer lines, location of
leaching field, depth and areal extent of the leach field, etc. could be ob-
tained. Soil data and percolation studies obtained for the leach field area
could be reviewed. Such data could show, for example, that the leaching field
is in tight clay soils, with slow intake rates, promoting anaerobic conditions
(i.e., inhibiting stabilization of organics). Because of slow intake rates,
clay soils would also limit the amount of wastewater seeping into the vadose
zone.
Sampling of raw sewage entering the septic tank and wastewater discharg-
ing from the tank could be collected for analysis. Automatic samplers could
be used to collect composite or discrete-time samples. In selecting samplers
of either type, guidelines from Harris and Keefer (1976) are useful. Collec-
tion of grab samples are another option.
Sampling wastewater in the leach field could involve installing shallow
sample PVC or steel wells down to the natural soil interface. Samples could
be pumped or bailed from the wells. A Teflon bailer designed by Dunlap
69
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et al. (1977) is recommended for collecting water samples for organics and
microorganisms.
An alternative method for sampling within the leaching field is to
install suction-cup lysimeters. The design and operation of these units are
described in by Everett et al. (1979) and Fenn et al. (1975). Note that the
ceramic cups may filter out microorganisms.
Potential pollutants in wastewater samples collected by the above could
be examined by alternative methods. For example, one method could entail
selectively analyzing samples for the major constituents (Ca, Mg, Na, K, HC03,
Cl, S04, P04, Si02, NH3-H, N03N, total nitrogen, organic nitrogen, pH,
and EC). Trace constituents could be examined selectively (B, Se, As, Fe,
Hg, Al, Zn, Cu, Cd, Cr, Ni). Organics may be examined by BOD, COD, DOC, TOC,
or oil and grease analyses. Microorganisms could be examined for any, all,
or some of the following: total coliform, fecal coliform, fecal strep, and
viruses. Various combinations of analyses from these constituent groupings
create numerous other options.
Preferred approaches include:
• Analyze the first 5 to 10 samples from the septic tank as com-
pletely as possible, i.e., for major inorganics, trace constitu-
ents, organics, and microorganisms. Subsequently, samples would
be analyzed only for those trace constituents, organics, or
microorganisms found in excess of recommended limits. All the
major inorganics would be analyzed completely in each sample.
• Completely analyze the initial 5 samples from the network of
wells in the leaching field. The sampling sites would be se-
lected at random, but would include at least one well near the
inlet and one well near the end of the leaching field. After
complete analyses (see above), subsequent samples for the leach-
ing field would be examined primarily for those constituents
found in excess.
Preliminary Recommendations--
The preferred monitoring approach is as follows:
« Inventory all sources discharging to the septic tank and esti-
mate the related quantities of fluids
• Review data on engineering design, leach field soils, and per-
colation tests in the leach field
• Install automatic samplers to collect composite samples of
wastewater discharging from the tank
• Install a minimum of two shallow wells in the leach field and
use Teflon bailer for sampling
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• Analyze samples as described earlier.
The costs for this step will initially be high because samples will be
completely analyzed. Later, as trends are established and the requisite num-
ber of analyses is reduced, the costs will concomitantly decrease. Specific
costs for this monitoring step are given in Appendix B, Table B-3, and
include:
• Labor costs for:
-- Inventorying and characterizing the septic tanks (i.e., col-
lection of engineering data, water quality analysis, etc.)
-- Characterizing the leaching field including collection of
soil data, results of percolation tests, etc.
-- Installation of composite samplers or for grab sampling, and
collection of samples
-- Installation of shallow wells in the leaching fields.
• Operational costs for:
-- Water quality analysis
-- Sample bottles, labels, etc.
• Capital costs for:
~ Composite samplers
-- Leach field wel1s
-- Teflon bailers.
Identify Potential Pollutants—Oxidation Ponds
Raw sewage could be treated by means of a "lagoon-type aeration plant"
(Everett, 1979). Some of the lagoons in the study area are developed in per-
meable sediments, fluvial deposits along diverted creeks. It is not known
whether or not these ponds are lined. However, if NPDES permits are not ob-
tained, it is assumed that no discharge will occur and that capacity is main-
tained by seepage, evaporation, and possibly by pumpage for road spraying.
This pond could operate as either a high-rate aerobic pond or as a faculta-
tive pond (oxygen provided by algae and wind action), or use mechanical aera-
tors (U.S. EPA, 1974). Treatment capacity of the ponds will depend on size
and engineering design for the anticipated loading.
Monitoring Needs-
Potential pollutants associated with normally functioning "aerated" la-
goons include major inorganics introduced with incoming sources (including
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phosphorous and nitrogen); possible trace contaminants; unstabilized organics;
bacteria, viruses, and other microorganisms. In the winter, ponds tend to
become anaerobic because of restricted biological activity. Anaerobic ponds
are not particularly effective in reducing nutrients, BOD, organics, or micro-
organisms. Note that facultative ponds have an anaerobic benthic region,
introducing reduced forms of nitrogen, sulfides, etc. into the underlying
vadose zone during seepage. As pointed out by Fuller (1977), the mobilities
of heavy metals and trace metals will, in general, be accelerated under
anoxic conditions.
The quality of wastewater within the pond will also be affected by dispo-
sal practices. For example, if evaporation is the principal mode of sustain-
ing storage capacity, dissolved suspended constituents will tend to increase
in concentration. In turn, pollutants entering the vadose zone will become
more concentrated.
Alternative Monitoring Approaches--
Nonsampling methods involve collecting and examining pollutant-related
information for a source, such as quantity of flows, collection of available
quality data, etc. The results of selecting nonsampling methods may indicate
that further monitoring activities are unwarranted. For example, it may be
found that the pond is lined.
One alternative method would consist of obtaining specific information
on the design of the pond, including type of operation (high-rate aerobic
pond, facultative pond, mechanically aerated pond); presence or absence of a
liner; type of liner, if present; interior dimensions of the pond; loading
rates; and plans of the sewer system. (If the pond is found to be lined with
a durable material, it may be elected either to cease the monitoring effort,
or to bypass intervening steps and determine the infiltration potential.
Results of the step would indicate either to cease the effort or to return
again to the first step.)
Copies of analytical data for the pond will be solicited from the mine
manager to determine the extent of ongoing monitoring and to specify poten-
tial pollutants.
Sources contributing to the oxidation pond could be inventoried, includ-
ing possible shop wastes, portable toilets, etc. One purpose of the inventory
would be to judge the possibility that toxic substances may be introduced
which could affect pond operation.
If information on the loading rate is unavailable, permission of the
mine manager could be requested to install suitable metering equipment (e.g.,
Palmer-Bowlus flumes) in manholes within the discharge line. The flume could
be equipped with a water stage recorder for continuous monitoring of flows.
Information obtained during the above procedures could be examined by a
competent sanitary engineer for a judgment on pond operation. Wastewater
samples could be collected from all sources discharging into the pond, pro-
vided that access is possible, e.g., by manholes. Sources include shop and
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office sanitary wastes and other discharges. Samples could also be collected
from the discharge pipe and at one or two locations within the pond.
Alternative water sampling techniques include grab sampling, automatic
composite sampling, and automatic discrete sampling. Grab samples are ob-
tained to determine instantaneous water quality. Composite samplers are used
to obtain blended water samples over a certain time interval (e.g., 24 hours).
Discrete samplers extract water samples at timed intervals. The relative ad-
vantages and disadvantages of these techniques for wastewater sampling are
reviewed by Harris and Keefer (1974).
Samples of the benthic solids could be obtained for analysis via a suit-
able hollow sampling tube.
Samples could be analyzed as described for septic tank wastewater. Field
analysis for unstable constituents, such as pH, EC, DO and alkalinity, and
additional spot checks for chloride and nitrate could also be performed.
This method will require the purchase of a pH meter, EC bridge, DO meter, and
a portable field kit (e.g., Hach Engineering Laboratory). When the results
of such field checks as pH, EC, chloride, and nitrate indicate a substantial
change between testing, samples would be collected for laboratory analysis.
Benthic solids could be examined in the laboratory for trace constitu-
ents and organics (grease, etc.).
Preliminary Recommendations--
A preferred monitoring approach for oxidation ponds is as follows:
• Inventory the sources of discharge to the oxidation ponds (util-
ize data gathered from inventory on sources collected for septic
tanks), engineering design, and method of operation
• Install water sampling and flow measuring equipment
• Indicate programs for field analysis, sample collection, and
monitor equipment maintenance
• Sampling frequency will be determined by field studies and bud-
get allocations.
The overall costs for this step will be high initially because of the
need for complete analysis of source samples. Later, sampling frequency and
requisite analyses will be reduced. The process of using field checks to de-
termine sampling frequency is another cost-reducing technique. Costs_for
monitoring an oxidation pond are given in Appendix B, Table B-3, and include:
• Labor costs for inventorying and characterizing sources, in-
stalling and operating water sampling and flow measuring equip-
ment, field checking quality, and collecting and transporting
samples.
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• Capital costs for purchasing composite or discrete samplers, for
equipment for field checking quality (pH meter, EC meter, etc.),
and for a sampling tube. These items will be general capital
items available for the overall TEMPO monitoring program. Con-
sequently, the proportionate charges against this source will be
low.
• Operating costs for analyzing samples. These costs will be high
initially but will lower as the list of constituents to examine
is narrowed and when field checks are used to guide sampling.
Identify Potential Pollutants—Package Plant
Mining plans indicate that sanitary wastes will be treated in package
plants commonly designed with a supplemental surge tank to prevent shock
loading.
Chlorinated effluent will be pumped to a sedimentation pond for reuse in
road sprinkling or irrigation. Sewage from chemical toilets will be dis-
charged into the package plant. Sludge will be buried in the spoil piles.
Pollutants in package plant effluent could impact on groundwater quality
if leakage should occur at the following locations: within the package plant
tanks, within the surge tank, within the pipeline transporting wastewater to
the sedimentation ponds, and within the sedimentation ponds. An overall ap-
proach for monitoring the sedimentation ponds is presented elsewhere in this
report (see Section 3, Monitoring Design for Mine Water Sources).
Monitoring Needs—
The following pollutants are normally associated with package plants:
organics, in the form of BOD, COD, DOC, or TOC; microorganisms (e.g., total
and fecal coliform, viruses, microscopic animals); and major and trace inor-
ganics occurring in concentrations above recommended limits. Also, a problem
inherent in package plant operation is that shock loadings tend to interfere
with treatment.
In light of limited information on existing monitoring at the package
plants, it is presumed that data deficiencies exist in the following categor-
ies: major inorganics (Ca, Mg, Na, K, POzj., Cl, $04, C03, HCO^, organic
nitrogen, NH3-N, N02-N, N03-N, and Si02); trace contaminants (Fe, Mn, Zn, Cu,
Cd, Cr, As, Pb, V, U, Th, and Se); organics (grease, oils, etc., and those
measured by BOD, COD, DOC, and TOC); and microorganics (total and fecal coli-
form, fecal strep, and viruses).
Alternative Monitoring Approaches--
One nonsampling monitoring method entails obtaining a copy of the speci-
fications of the plant from the mine manager. Similarly, information could
be obtained on the design and construction of the surge tank. At the same
time, information could be obtained on the chlorination unit, together with
data or chlorine usage, chlorine demand, and chlorine residual.
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Sources contributing to the package plant could be inventoried, includ-
ing shop wastes and portable toilets. A purpose of the inventory is to esti-
mate the possibility that toxic substances may be discharged periodically.
Such substances interfere with plant operation and introduce exotic pollutants
into the waste stream.
Information on the number of personnel using the sanitary and other
wastewater facilities in a 24-hour period could be solicited from the mine
manager.
Another alternative method comprises obtaining information on the load-
ing rates of the package plant from the mine operator. If such information
is unavailable, permission could be requested to install suitable metering
devices (e.g., Palmer-Bowlus flumes) in the incoming lines. A flow meter
could be installed in the line between the package plant and the surge tank.
Interaction of the plant and surge tank could be characterized routinely,
particularly relating to the period that the flow is held in storage.
Copies of quality data for the package plant could be requested to spe-
cify the extent of ongoing monitoring and to define pollutants. Information
on specific analytical techniques of quality control measures could be ob-
tained at this time.
Sampling methods of evaluating raw wastewater entering the plant and
treated effluent could be done by alternative methods such as by composite or
discrete automatic samplers, or by grab sampling. Composite samplers produce
a single blended sample obtained by pumping from the sampling stream at peri-
odic intervals. Discrete samplers provide a series of individual samples
collected at timed intervals. Grab samples are obtained by manually dipping
the sample container into the source. Guidelines of Harris and Keefer (1974)
will be followed in selecting automatic samplers.
Samples of wastewater discharging into the sedimentation ponds could
also be obtained via any or all of the above alternative sampling methods.
Samples from the discrete samples could be analyzed completely for the
major inorganics (Cu, Mg, K, Na, Cl, S04, NH3-N, N02-N, N03-N, HC03, C03,
SiC"2, P04, etc.); trace constituents (Fe, Zn, V, Cu, No, Cd, Ra, Se, etc.);
organics (measured by BOD, COD, TOC, DOC); and microorganisms (total and
fecal coliform, viruses, etc.).
Alternatively, samples from the discrete samplers could be analyzed only
for BOD until trends are characterized.
A third alternative method for examining discrete samples could be par-
tial analyses for those constituents found in concentrations above permissible
1 imits.
Analyses of composite and grab samples could parallel those above for
discrete samples: complete analyses, partial analyses for BOD, or partial
analyses for specific constituents.
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The discrete samplers could be activated at various timed intervals; for
example, hourly, bihourly, etc. Similarly, these samplers could be used on a
daily basis, weekly basis, etc. The 24-hour composite samplers could be used
on a daily, weekly, or monthly basis. Grab samples could also be obtained at
alternative frequencies, e.g., hourly, daily, weekly, etc.
A preferred approach to sampling frequency includes:
• Collect 2-hour samples on the discrete sampler installed in
package plant inlet and outlet ports, at daily intervals until
trends in BOD have been characterized
• Collect 6-hour discrete samples for complete analysis, once a
week, until quality trends are established
• Collect 24-hour composite samples once a month from the inlet
and outlet ports in the package plant
• Collect 2-hour water samples at the discharge point into the
ponds, using a discrete sampler, at daily intervals until BOD
trends are established. Thereafter, sample every 6 hours via
the discrete sampler, one day a week until quality trends are
established. Thereafter, collect a grab sample once every 2
weeks.
Preliminary Recommendations--
The preliminary monitoring recommendation incorporates both nonsampling
and sampling methods. This approach would include the following:
• Obtain available information on the package plant design, in-
cluding the interaction with the surge tank and chlorinator
design and operation.
• Interview mine personnel to determine plant usage, sewer line
distribution and drain line to sedimentation pond, toxic sub-
stances flushed into the system, loading rates.
• Install an automatic discrete sampler in the inlet and discharge
ports, and collect 2-hour samples for BOD and coliform.
• Collect 6-hour discrete samples via the automatic sampler, once
BOD and coliform trends have been established.
• Install a 24-hour composite sampler in the inlet and outlet
ports once trends in quality (major inorganics, trace constitu-
ents, organics, and microorganisms) have been characterized.
Activate samples for a 24-hour period once every month.
• Install a discrete sampler in the discharge point to the pond
and collect 2-hour samples for BOD. After BOD trends are
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established, collect 6-hour samples for complete analyses. Once
general quality trends are characterized, collect grab samples.
All samples will be collected, preserved, stored, and transported in
accordance with recommended techniques.
Cost for the monitoring program would include labor for inventorying
plant design and quality data, installing sampling instruments, and collect-
ing and transporting water samples. Operating costs would include analyzing
samples, capital costs for sampling equipment, and flow measuring instrumen-
tation. These costs are summarized in Appendix B, Table B-3.
Identify Potential Pollutants—Sludge
Sanitary wastes from the active mines will be treated by the sewage
treatment and package plants described herein. In accordance with some of
the reviewed mining plants, inert sludge from the treatment plants will be
mixed with the topsoil and placed on the graded spoils.
According to Hammer (1977), the mixed liquor in extended aeration (pack-
age) plants increases in concentration over a period of several months and is
then pumped from the aeration basin. The mixed liquor suspended solids (MLSS)
operating range varies from 1000 to 10,000 ppm.
Hammer presented an example of build-up time in a typical small extended
aeration plant assuming a loading rate of 170 g/m3 per day BOD, an aeration
period of 24 hours, and a measured suspended solids build-up rate of 30 ppm
per day. If the MLSS concentration in this plant were permitted to increase
from 1000 ppm to 10,000 ppm before wasting the solids, the build-up time
would be 300 days.
In a discussion of extended aeration plants, Vesilind (1976) indicated,
". . . the ecology within the aeration tank is quite diverse and little ex-
cess biomass is created, resulting in little or no waste activated sludge to
be disposed of . . . ."
In light of the potentially low build-up time prior to sludge disposal
and the small amount of sludge produced each year, it is apparent that this
source is insignificant vis-a-vis other sources on the mine. Consequently,
the possibility of groundwater pollution from pollutants in sludge will be
miniscule. This report will, therefore, be limited to source pollutant moni-
toring.
Monitoring Needs--
Sewage sludge contains the macro plant nutrients (nitrogen, phosphorous,
and potassium) in concentrations that are about one-fifth of those found in
commercial fertilizers (Wyatt and White, 1975). Of these constituents, nitro-
gen in the nitrate form is the pollutant of greatest concern. The metal con-
tent of sludge is also of importance as a pollutant. In particular, zinc,
copper, nickel, and cadmium are likely to be present in excessive concentra-
tions. Previously, it was surmised that high metal concentrations reflected
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input from industrial waste sources. However, according to the Environmental
Protection Agency (1974), metal concentrations are high even in wastewater
predominantly of domestic origin. Sludges may also contain pesticides and
polychlorinated biphenols (Wyatt and White, 1975), and pathogenic organisms,
unless pasteurized.
Until additional information is obtained on monitoring for sludge pollu-
tants, it is assumed that data deficiencies exist in defining: major inorga-
nics, trace constituents, organics (including polychlorinated biphenols and
other organic toxins flushed into the sewer system), microorganisms, solid
MLSS, and mass of sludge produced each year.
Alternative Monitoring Approaches--
The volume of sludge deposited in the package plant could be estimated
each time the aeration basin is pumped. In addition, the frequency of pump-
ing could be noted.
The disposition of sludge could be determined. For example, the loca-
tion of stockpiles receiving sludge could be noted, together with areas which
are spread with soil-sludge mixtures. Such locations could be defined on a
base map for the mine.
The sources of wastewater could be determined, particularly to determine
the influx of toxic chemicals. Analytical data on wastewater, sludge, and
soil-sludge mixtures could be solicited from the mine manager.
Samples of sludge from the package plant could be obtained via a special
brass sampler equipped with valves and a pull cord. Alternatively, an inex-
pensive sampler could be constructed by attaching a wide-mouthed stoppered
bottle to the end of a pole. The bottle is positioned at the desired depth
in the sludge, and the stopper is uncorked with a cord.
When sludge is being pumped, grab samples of equal size could be ob-
tained at various times. It is recommended that grab samples be obtained at
the start, during, and at the end of the pumping period.
Samples of dried sludge could be obtained from the soil piles on which
the sludge is disposed. The recommended sampling procedure is to take por-
tions of equal size from scattered points on the bed, taking care not to
include sand, mix thoroughly after pulverizing, and use about 500 grams for
the laboratory sample.
During rehabilitation of spoil piles, samples of soil-sludge mixtures
could be obtained from the spreading area. Possible sampling methods include
shovels and augers.
A preferred sampling approach will include:
• Sample sludge from the package plant tanks via a pole and bottle
sampler
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• Collect grab samples of sludge at the beginning, during, and at
the end of pumping periods; the samples will be mixed together
• Collect sludge samples from soil piles using the recommended
techniques in Laboratory Procedures for Wastewater Treatment
Plant Operations (New York State Department of Health, no date)
• Collect samples of soil-sludge mixture from the spreading areas
via a hand auger; collect 5 to 10 samples at random locations.
Collected sludge samples and sludge-soil mixtures could be subjected to
any or all of the following analyses: suspended solids, volatile solids,
major inorganics, trace contaminants, organics, and microorganisms. The con-
centration of suspended solids in samples collected from the aeration tank is
called mixed liquor suspended solids. If BOD is also determined on the in-
coming raw sewage, the ratio of BOD to MLSS represents the loading of the
system (Vesilind, 1974).
Some of the possible specific techniques for sludge analyses were sum-
marized by Sommers, Nelson, and Yost (1976). These included: gravimetric
determination of solids and ash after drying at 105°C (16 hours), followed
by igniting at 650°C; gravimetric determination of CO? liberated by F^SO^-
h^PO^I^C^Oy digestion, as a measure of total C; titremetric determination
of inorganic C after treating samples with 2M HC1; determination of organic C
by difference; determination of total -N by a modified micro-Kjeldahl proce-
dure; determination of soluble plus exchangeable NH4 and NO^ by steam dis-
tillation techniques after 2M KC1 extraction; determination of organic nitro-
gen by difference; determination of total P by colorimetry after HN03 - HC104
digestion; determination of inorganic P by colorimetry after 1W HC1 extrac-
tion; and determination of organic P by difference. According to Sommers,
Nelson, and Yost (1976), samples digested with HN03 - HC104 are analyzed for
Ca, Mg, Cd, Pb, Ni, Cu, Zn, and Cr by atomic absorption spectrophotometry; K
by flume emission; and Fe by colorimetry.
Sludge samples could be obtained from the four sampling sites at highly
variable frequencies, e.g., daily, weekly, monthly, or yearly. A preferred
approach will be:
• Sample sludge and incoming wastewater in the plant at monthly
intervals until trends in the loading rate become apparent;
thereafter, sample every 6 months
• Sample pumped sludge once a year
• Sample for soil-sludge stockpile once when sludge i| first
dumped on the pile and 6 months later (losses in NH4 would
be quantified by this technique
• Sample from soil-sludge areas on the reclaimed spoil pile.
79
-------
Preliminary Recommendations--
A nonsampling monitoring approach is recommended which would consist of
the following:
• Corroborate sludge monitoring effort with sewage treatment and
package plant studies
• Collect sludge samples at package plant via pole and bottle sam-
pler and grab samples during pumping periods.
Expenditures for sludge monitoring will be kept to a minimum due to the
small annual production of this waste material. Labor costs for infrequent
sludge sampling during plant pumpage and limited chemical analysis, field
transportation, and miscellaneous capital costs would comprise the only expen-
ditures for this monitoring step. These costs are summarized in Appendix B,
Table B-3.
Define Groundwater Usage
Liquid and solid miscellaneous mine sources would impact a defined
groundwater usage based on its location and physical characteristics. As no
one miscellaneous source is representative of this group the reader is re-
ferred to sources given in Sections 2 and 3 which most closely fit the mis-
cellaneous source of interest. In most cases, monitoring miscellaneous
sources would be incorporated into a monitoring program for another mine
source. However, some additional site-specific impact from leaks in the san-
itary treatment system or container spills and leaks may require individual-
ized study. For these, the reader should reference a sample similar to the
miscellaneous source of interest to develop appropriate monitoring needs,
alternative monitoring approaches, and a specific preliminary recommendation
to meet his needs.
Define Hydrogeologic Situation
Data required to evaluate the hydrogeologic framework, sources of infor-
mation, monitoring needs, alternative monitoring approaches, and preliminary
recommendations for developing monitoring designs have been described earlier.
The reader should refer to Sections 2 and 3 for detailed information for this
monitoring step.
Study Existing Groundwater Quality
Defining existing groundwater quality for miscellaneous mine sources
would overlap similar monitoring efforts for major sources. Networks of mon-
itor wells or sampling stations should be developed with the location of mis-
cellaneous sources in mind. Defining concentrations of pollutants upgradient
and downgradient from the sources would be the ideal situation; however, bud-
getary restrictions may preclude such detailed results. For a detailed dis-
cussion of monitoring needs, approaches, and installation of monitoring equip-
ment see Sections 2 and 3 of this report.
80
-------
Evaluate Infiltration Potential
The extent to which monitoring of the infiltration potential of miscel-
laneous mine sources is unknown. Presumably, sources associated with mine
sanitary waste treatment facility (e.g., oxidation ponds, leach fields),
could have limited infiltration data based on percolation tests. It is as-
sumed that data on other miscellaneous liquid and solid mine wastes are lack-
ing. Information on monitoring designs for these sources can be obtained in
Sections 2 and 3 herein.
Evaluate Mobility in the Vadose Zone
No information was available for review on monitoring or potential pol-
lutant mobility in this vadose zone for miscellaneous mine sources. These
data are assumed to be nonexistent. Data bases could be generated using mon-
itoring designs described earlier in this volume.
Evaluate Attenuation of Pollutants in the Saturated Zone
Data on pollutant mobility and attenuation in the saturated zone for
miscellaneous mine sources are unknown. Monitoring designs for these studies
are given in Sections 2 and 3 for solid and liquid potential pollutant source,
respectively.
81
-------
REFERENCES
AMAX Coal Co., Mining Plan Update for Belle Ayr South Mine, Campbell County,
Wyoming, 1976.
AMAX Coal Co., Mining Plan Update for Belle Ayr South Mine, Campbell County,
Wyoming, 1977.
Black, C.A. (ed.), Methods of Soil Analysis, Part 2, Chemical and Microbio-
logical Properties, in AGRONOMY, Series 9, American Society of Agronomy,
Madison, Wisconsin, 1965.
Bouwer, H., and R.D. Jackson, "Determining Soil Properties," Draining for
Agriculture, J. Van Schilfgaarde (ed.), in AGRONOMY, Series 17, American
Society of Agronomy, Madison, Wisconsin, 1974.
Brown, E., M.W. Skougstad, and M.J. Fishman, Methods for Collection and Analy-
sis of Water Samples for Dissolved Minerals and Gases, U.S. Geological
Survey, Techniques of Water-Resources Investigations, Book 5, Chapter
Al, 160 pp, 1970.
Cordero Mining Co., Mining Plan Update, Wyoming Department of Environmental
Quality, Cheyenne, Wyoming, 1976.
Craig, G.S., Jr., and J.G. Rankl, Analysis of Runoff from Small Drainage
Basins in Wyoming, USGS Open File Report 77-727, September 1977.
Davis S.N., and R.J.M. DeWeist, Hydrogeology, John Wiley and Sons, Inc., New
York, 1966.
Dunlap, W.J., J.F. McNabb, M.R. Scalf, and R.L. Cosby, Sampling for Organic
Chemicals and Microorganisms in the Subsurface, Robert S. Kerr Environ-
mental Research Laboratory, prepared for U.S. Environmental Protection
Agency, EPA-600/2-77-176, 1977.
Everett, L.G. (ed.), Groundwater Quality Monitoring of Western Coal Strip
Mining: Identification and Prioritization of Potential Pollution
Sources, EPA-600/7-79-024, U.S. Environmental Protection Agency, Moni-
toring and Support Laboratory, Las Vegas, Nevada, January 1979.
Fenn, D.G., K.J. Hanley, and T.V. DeGeare, Use of the Water Balance Method
for Predicting Leachate Generation from Solid Waste Disposal Sites,
EPA/530/SW-168, U.S. Environmental Protection Agency, Cincinnati, Ohio,
1975.
82
-------
Fuller, W.H., Movement of Selected Metals, Asbestos, and Cyanide in Soil:
Applications to Waste Disposal Problems, U.S. Environmental Protection
Agency, EPA-600/2-77-020, 1977.
Hammer, M.J., Water and Waste-Water Technology, J. Wiley and Sons, Inc., New
York, New York, 1977.
Hansen, E.A., and A.R. Harris, "A Groundwater Profile Sampler," Water Re-
sources Research, Vol 10, No. 2, 1974.
Harris, D.J., and W.J. Keefer, Wastewater Sampling Methodologies and Flow
Measurement Techniques, U.S. Environmental Protection Agency EPA
907/9-74-005, 1974.
Lohman, S.W., Ground-Water Hydraulics, U.S. Geological Survey Professional
Paper 708, Washington, D.C., 1972.
Montana Coal and Uranium Bureau, Department of State Lands, Overburden Stock-
pile Materials, 1978.
Mooji, H., and F.A. Rovers, Recommended Groundwater and Soil Sampling Proce-
dures, Environmental Protection Service, Report EPS-4-EC, 76-7, Canada,
Pickens, J.F., J.A. Cherry, G.E. Grisak, W.F. Merrit, and B.A. Risto, "A
Multi-Level Device for Ground-Water Sampling and Piezometric Monitor-
ing," for submi-ttal to Ground Water, 1977.
Soil Conservation Service, Soil Conservation Service Engineering Handbook,
Section 5, U.S. Department of Agriculture, 1972.
Sommers, L.E., D.W. Nelson, and K.J. Yost, "Variable Nature of Chemical Com-
position of Sewage Sludge," Journal of Environmental Quality, Vol 5,
No. 3, pp 303-306, 1976.
Sun Oil Co., Final Environmental Statement, Proposed Plan of Mining and Recla-
mation, Cordero Mine, Campbell County, Wyoming, 1976.
Thatcher, L.L., V.J. Janzer, and K.W. Edwards, Methods for Determination of
Radioactive Substances in Water and Fluvial Sediments, U.S. Geological
Survey, Techniques of Water-Resources Investigations, Book 5, Chapter
A5, 95 pp, 1977.
Todd, O.K., R.M. Tinlin, K.D. Schmidt, and L.G. Everett, Monitoring Ground-
water Quality: Monitoring Methodology, U.S. Environmental Protection
Agency, Monitoring and Support Laboratory, EPA/600/4-76-026, Las Vegas,
Nevada, 1976.
U.S. Department of Interior, Surface Mining Control and Reclamation Act of
1977 (30 CFR, Chapter VII), 1977.
U.S. Environmental Protection Agency, Process Design Manual for Sludge Treat-
ment and Disposal, EPA Technology Transfer, EPA-625/1-74-006, 1974.
83
-------
U.S. Geological Survey, Final Environmental Statement, Proposed Plan of Mining
and Reclamation, Belle Ayr South Mine, AMAX Coal Company, Coal Lease
W-0317682, Campbell County, Wyoming, FES75-86, 1975.
U.S. Geological Survey, Draft Environmental Statement, Proposed Mining and
Reclamation Plan, Eagle Butte Mine, AMAX Coal Company, Coal Lease
W-0313773, Campbell County, Wyoming, DES 76-36, 1976.
Vesilind, P. Aarne, Treatment and Disposal of Wastewater Sludges, Ann Arbor
Science Publishers, Ann Arbor, Michigan, 1974.
Wyatt, J.M., and P.E. White, Jr., Sludge Processing, Transportation and Dispo-
sal/Resource Recovery: A Planning Perspective Water Quality Management
Guidance, U.S. Environmental Protection Agency, WPD-12-75-01, 1975.
Wyoming Department of Environmental Quality, Division of Land Quality, Guide-
line No. 1, Soil and Overburden Guidelines, April 1978.
84
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APPENDIX A
METRIC CONVERSION TABLE*
Nonmetrlc units
inch (in)
feet (ft)
square feet (ft2)
yards
square yards
miles
square miles
acres
gallons
cubic feet (ft3)
barrels (oil)
acre/ft
gallons/square foot per minte
cubic feet/second
gallons/minute^
gallons/day
million gallons/day
pounds
tons (short)
pounds/acre
parts per million (ppm)
Multiply by
25.4
2.54
0.3048
0.290 x ID'2
91.44
0.914
1.6093
3.599
4.047 x 103
,047 x ID'1
103
io-3
.785
,785
.785
1.590 x 102
1.108 x IO7
40.74
3.532 x 102
6.308 x ID'2
3.785
28.32
0.028
0.454
4.536 x 10~4
9.072 x 102
0.907
1.122
1
Metric Units
millimeters (mm)
centimeters (cm)
meters (m)
square meters (m2)
centimeters (cm)
square meters (m^)
kilometers (km)
square kilometers
square meters
hectares (ha)
cubic centimeters
cubic meters
1iters
1iters
1iters
1iters/square meter per minute
1iters/second
1iters/second
liters/day
1iters/second
cubic meters/second
kilograms
tons (metric)
kilograms
tons (metric)
kilograms/hectare
milligrams per liter (mg/1)
* English units were used in this report because of their current usage and
familiarity in industry and the hydrology-related sciences.
1 gpm = 1.6276 afa.
85
-------
86
-------
APPENDIX B
SUMMARY OF PRELMINARY MONITORING DESIGNS
87
-------
TABLE B-l. SUMMARY OF PRELIMINARY MONITORING DESIGN FOR TOPSOIL STOCKPILES, FOR OVERBURDEN STOCKPILES,
AND FOR COAL, COAL REFUSE AND COALY WASTE STOCKPILES
TEMPO monitoring
steps3
Monitoring needs
Alternative monitoring
approaches
Preliminary
recommendations
Moni tori ng costs
Identify potenti al
pollutants (topsoil
stockplles)
oo
CO
Determine volume,
location, and antic-
ipated duration of
stockpi1es
Determine undisturbed
soil characteristics
Determine physical
and chemical altera-
ti ons of soi1s wi th
time (old stockpiles)
1. Nonsampling method
a. Compile data on stockpiles'
volume and location from aerial
photography or mine engineering
and production records
b. Determine soil characteristics
from soil inventory maps
2. Sampl i ng method
a. Compile data on stockpiles'
volume and location by field
measurements
b. Determine soil characteristics
by chemical analysis for major
inorganics, trace constituents,
organics, and microorganisms
1. Obtain soil inventory maps
2. Determine topsoil removal
and stockpile locations from
mine engineering and produc-
tion records
3. Sample oil stockpiles (1 year
or more) annually for chemi-
cal analysis of major inor-
ganics, trace constituents,
and organics
1. Labor
a. Review soils map (1 week):
$300
b. Interview mine personnel
(1 week): $200
c. Sample handling, preparation,
quality control, etc.:
$10/sample
2. Operation
a. Chemical analysis: $100/
sample
b. Air freight, refrigeration,
packing, etc.: $10/set of
1 to 3 samples
3. Capital
a. Sample container, labels,
chemicals, etc.: $2.50/sample
b. Hand-driven soil sampler: $500
Identify potenti al
pollutants (over-
burden stockpiles)
1. Determine chemical
composition of in-
place overburden
2. Determine volume,
composition, and ex-
pected 1ife of over-
burden stockpiles
3. Determine dynamic
nature of disturbed
overburden through
time
1. Nonsampling method
a. Review existing data on in-place
overburden (i.e., water well or
core hole lithologic logs,
geophysical logs, core sample
analyses, etc.)
b. Determine volume and location
of overburden stockpiles through
engineering production records
or aerial photographs
c. Determine estimated duration of
stockpiling from mine engineer-
ing and production records
2. Sampling method
a. Compile volumetric and chemical
data from field and laboratory
analysis
1. Review existing data on
chemical constituents .of
in-place overburden
2. Measure volume of overburden
stockpiled
.3. Sample stockpiles (a minimum
of 2 samples per location or
every 10 feet of thickness),
1 hole for every 10 acres of
surface area
4. Conduct annual analyses for
parameters given in Table 1
1. Labor
a. Review existing data (1 week):
$300
b. Survey stockpiles (volume),
2 weeks, surveyor and assis-
tant: $1,000
c. Sample handling, preparation,
quality control, etc.: $10/
sample
2. Operation
a. Chemical analysis: $100/sample
b. Air freight, refrigeration,
packing, etc.: $10/set,
1 to 3 samples
c. Field transportation:
$2/sample
a Subsequent monitoring steps for topsoil are similar to those for overburden and coal, coal refuse, and coaly waste stockpiles
-------
TABLE B-l (continued)
TEf-'PO moni tor ing
steps3
Identify potenti al
pollutants (over-
burden) (continued)
Alternative monitoring
Monitoring needs approaches
2. Sampling method (continued)
b. Sample new and olj (more than
Prel imi nary
recommendations Monitoring costs
3. Capital
a. Sample containers, labels,
1 year) stockpiles to determine
chemical changes, analyze for
parameters given in Table 1
chemicals, etc.: $2.50/sample
b. Hand-driver soil sampler: $500
CO
Identify potential
pollutant (coal,
coal refuse, and
coaly waste
stockpiles!
1. Determine soluble
sal ts in the coal
resource
2. Determine chemical
characteristic of
coaly wastes
1. Nonsampl ing method
a. Determine method and duration
of stockpiling from mine engi-
neering and production reports
b. Determine potential pollutants
of coal from existing chemical
data
2. Sampling method
a. Determine method of stockpiling,
location, and volume from field
surveys, take grab samples
b. Analyze grab samples for Ag,
Pb, Se, rig, As, Mo, Cu, Cd, Mn,
B, Ge, U, Ni, In, Cr, Be, V, F
1. Determine volume of coal
and coaly waste from field
measurements
2. Review existing data on
chemical characteristic of
stockpiled materials to
estimate volume of potential
pollutants therein
3. Utilize sample collection to
fill in data gaps found in
data review above
1. Labor
a. Review chemical data on coal
and coaly waste (1 week): $300
b. Survey coaly waste stockpiles
(volume), 1 week, surveyor and
assistant: $500
c. Sample handling, preparation,
quality control, etc.: $10/
sample
2. Operation
a. Chemical analysis (if re-
quired): $100/sample
b. Air freight, refrigeration,
packing, etc.: $10/set,
1 to 3 samples
c. Field transportation:
$2/sample
3. Capital
a. Sample containers, labels,
chemicals, etc.: $2.50/sample
Define qroundwater
usage (topsoil
stockpiles)
1. Determine irrigation 1. Install irrigation metering devices 1. Determine if irrigation is 1. Labor
water qua!i ty and
quantities for
revegetation
2. Determine vegetation consumptive
water use and water quality toler-
ances from soil characteristics
and selected vegetation cover
planned for stockpiles
2. Monitor irrigation water,
if required
a. Determine irrigation schedule
from mining plans (1 day): $40
b. Install monitoring equipment
in irrigation system, if re-
quired (1 day): $60
2. Operation
a. Record water usage, maintain
monitoring equipment (if re-
quired): $2.50/measurement
3. Capital
a. Flow meter: $40
-------
TABLE B-l (continued)
TEMPO monitoring
steps3
Monitoring needs
Alternative monitoring
approaches
Preliminary
recommendati ons
Monitoring costs
Define hydrogeo-
geologic situation
Define regional and
local geology, aqui-
fer locations, inter-
actions and character-
istics, groundwater
depths, flow rates,
and recharge/discharge
relationships {source
specific and regional)
1. Nonsampling method
a. Compile hydrogeologic data from
mine operators, U.S. Geological
Survey, State agencies, private
consultants (i.e., well con-
struction methods, depth, diam-
eter, producing aquifers, com-
pletion techniques, driller's
logs, geophysical logs, etc.)
2. Sampling method
a. Measure water levels and pump
test existing wells
1. Review data defined in
nonsampling method
2. Sample existing monitor wells
if supplemental data are
required
3. Install site-specific monitor
wells if further data are
required and justified by
subsequent monitoring steps
1. Labor
a. Compile and review existing
hydrogeologic data (2 weeks):
$600
b. Sample handling, preparation,
quality control, etc.: $5/
sample
2. Operation
a. Chemical analysis: $200/sample
b. Packing and air freight to
laboratory: $25/set, 4 to 8
samples
c. Field transportation:
$2/sample
d. Portable pump for sampling:
$30/sample
3. Capital
a. Electronic sounder: $200
b. Bottles, labels, field books,
etc.: $2.50/sample
Study existing 1. Determine chemical 1. Nonsampling method
groundwater quality quality of ground-
water (regionally or a
site specific)
Determine groundwater quality
from existing records (i.e.,
mining companies, U.S. Geologi-
cal Survey, State agencies,
private consultants, etc.)
2. Sampling method
a. Sample existing monitor wells
via submersible pumps
b. Install new monitor wells and
sample as above
1. Evaluate existing groundwater
quality data
2. Initiate sampling program of
existing wells
3. Begin periodic field checks
and collect laboratory sam-
ples when marked changes
occur between field
measurements
4. Install site-specific moni-
tor wells if subsequent
studies indicate pollutants
are entering the saturated
zone
1. Labor
a. Compile and review existing
groundwater quality data
(2 weeks): $600
b. Sample existing wells and con-
duct periodic field checks:
$7/hr
c. Sample handling, quality con-
trol, laboratory preparation:
$5/sample
d. Drilling labor and supervision
for new monitor wells: $93/hr
-------
TABLE B-l (continued)
TEMPO monitoring
steps3
Monitoring needs
Alternative monitoring
approaches
Prelimi nary
recommendati ons
Moni tori ng costs
Study existing
groundwater
(continued)
c. Analyze samples for major inor-
ganics (Ca, Mg, Na, K, HC03,
Cl, $04, P04, SiOj, NH3-N,
total N, pH, and EC), trace con-
stituents (Fe, Mg, Zn, Cu, Cl,
Cr, As, Mo, V, U, Th, Ru, and
Se), organics (measured by BOD,
DOC), and microorganisms (total
and fecal coliform)
d. Conduct field analysis of sam-
ples collected, including pH,
electrical conductivity, dis-
solved oxygen, alkalinity,
chloride, and nitrates
e. Pumping tests (3 persons):
$140/day
f. Drill site geologist: $7/hr
2. Operation
a. Chemical analysis: $200/sample
b. Packing and air freight for
water quality samples:
$25/set, 4 to 8 samples
c.Field transportation:
$2/sample
d. Pumping tests (equipment oper-
ation): $3,000/test
3. Capital
a. Bottles, labels, chemicals,
etc.: $2.50/sample
b. Field kit, bailer, storage
chest: $750
c. Hardware and supplies to
complete wells: $15/ft
Evaluate infiltra-
tion potential
(topsoil stockpiles)
1. Determine migration
of fluids through
the stockpiles
1. Sampling method
a. Determine water penetration
using field infiltrometer for
natural and applied water
conditions
1. Install 3 or more ring infil- 1. Labor
trometers on each stockpile
as dictated by variation in a. Installation of inf iltrometer:
stockpiled material s $10
b. Conduct infiltration test:
$9/test
2. Operation
a. Field transportation and
equipment maintenance (in-
cluded in infiltration test)
3. Capital
a. Double-ring inf iltrometer:
$150
-------
TABLE B-l (continued)
TEMPO moni Coring
steps9
Eval uate mobi 1 i ty
of pollutants in
the vadose zone
Monitoring needs
1. Determine movement
and attenuation of
pollutants in vadose
zone
Alternative monitoring
approaches
1. Sampl i ng method
a. Determine ansaturated flow
beneath stockpiles using neu-
tron probes and tensiometers
Prel imi nary
recommendati ons
1. Install access tubes for
neutron probes and corrobor-
ate data with inf iltrometer
analysis
Monitoring costs
1. Labor
a. 100-ft
hole:
neutron probe access
$250/site
UD
ro
Evaluate attenua-
tion of pollutants
in the saturated
zone
1, Determine attenuation
of pollutants in the
zone of saturation
b. Collect soil solutions in porous
cups for chemical analysis,
major inorganics, pH, and elec-
trical conductivity
1. Compare local and regional back-
ground data with samples collected
near source
2. Install site-specific monitoring
wells near potential pollutant
source
2. Install lysimeters if neutron
probe indicates appreciable
fluid movement
No monitoring would be con-
ducted unless infiltration
and neutron probe analyses
indicated appreciable flow
through the stockpiles and
vadose zone
b. Neutron logging survey:
$50/site
c.Lysimeter installation and
tests: ISO/sample
d. Sample handling, preparation,
quality control, collection:
$5/sample
2. Operation
a. Field transportation, sample
collection: $2/site
b. Air freight, packing for water
quality samples: $10/set,
1 to 3 samples
3. Capital
a. Neutron moisture probe and
generator: $15,000
b. Lysimeters: $21 each
c. Bottles, chemicals, labels,
etc. : $2.50/sample
d. Seamless steel pipe: $3.12/ft
Labor, operation, and capital costs
for sampling and well installation:
See "study existing groundwater
quality" monitoring step
-------
TABLE B-2. PRELIMINARY MONITORING DESIGN—MINE WATER SOURCES
TEMPO monitoring
stepsa
Identify poten-
tial pollutants
(sedimentation
ponds)
Monitoring needs
1. Characterize discrete 1.
sources and pollutants
entering the sedimen-
tation ponds
2. Determine chemical
characteristics and
water quality trans-
formations throughout
the pond
Alternative monitoring
approaches
Nonsampl ing method
a. Compile pollutant-specific information
relating to sedimentation pond from
mining companies (i.e., sewage treatment
and package plant operations and discharge
characteristics; pit dewatering; runoff
from spoils and regraded areas)
b. Review National Pollutant Discharge Elimi-
Prel iminary
recoinmendati ons
1. Review available water
quality data including
NPDES permits
2. Sample pit water and
sewage effluent via
discrete or composite
samplers
3. Sample surface runoff at
Moni toring costs
1. Labor
a. Compile and review water
quality data (1 week):
$300
b. Sample handling, labora-
tory preparation, quality
control etc.: $5/sample
GO
nation Systems (NPDES) permits for water
quality data
c. Determine pollutant loading by measuring
discharge into ponds
d. Conduct inventories of diffuse sources
contributing possible pollutants to ponds
[see miscellaneous sources (Section 4)
contributing to surface runoff)
2. Sampling method
a. Sample pit water discharged into ponds
b. Sample package plant effluent and miscel-
laneous sources on surface runoff at pond
i nlets
c. Sample pond water at various locations,
depths and at outfall point to determine
water quality transformations
d. Sample pond overflow at downstream
locations
e. Sampling above can be done by grab, auto-
matic composite, and automatic discrete
methods
f. Samples could be analyzed for major inor-
ganics (Ca, Mg, Ma, K, HC03> Cl, S04, P04,
Si02, NH3-N, total N, pH, and EC), trace
constituents (Fe, Mg, In, Cu, Cl, Cr, As,
Mo, V, U, Th, Ru, and Se, cyanide), or-
ganics (oils, grease, and those measured
by BOD, DOC), and microorganisms (total
and fecal coliform)
g. Determine water quality of the first few
samples using (f) above and monitor sub-
sequent samples by analyzing for major
organics only
pond inlet (grab)
d. Sample pond water at
various locations and
and depths
5. Sample pond overflow at
outfall and downstream
6. Samples (first five)
would be analyzed com-
pletely; subsequent sam-
ples for rnajor inorganics
only; field samples would
be analyzed for chlorides
and nitrates
c. Sampling equipment instal-
lation: $40/day
d. Field checks of water
quality: $2.50/sample
2. Operational
a. Chemical analysis:
S200/sample
b. Field transportation:
S2/sample
c. Packing, air freight for
water quality samples:
$25/set, 4 to 8 samples
3. Capital
a. Automatic sampler: $600
b. Wide-mouth bottle sampler:
$10
c. Field kit, storage chest:
$730
d. Bottles, labels, chemi-
cals: $2.50/sample
a Subsequent monitoring steps for sedimentation ponds are similar to those for a pit water source
-------
TABLE B-2 (continued)
TEMPO monitoring
steps3
Monitoring needs
Alternative monitoring
approaches
Preliminary
recommendations
Monitoring costs
Identify poten-
tial pollutants
(sedimentation
ponds)
(conti nued)
h. Define water quality by field analysis for
nitrate and chloride
i. Sampling interval will be determined
through site-specific study and budget
allocated for analytical work; a pre-
ferred approach to sampling frequencies
is given in the text
Identify poten-
tial pollutants
(pit water)
Determine the quan-
tity and quality of
water in the pit
Characterize discrete
sources contributing
to the pit water
1. Nonsampling method
a. Compile existing data on discrete pit
water sources from mining company records
(stream channel leakage, sewage treatment,
or package plant effluent), and miscella-
neous sources (Section 4)
b. Evaluate diffuse sources (seepage and
nonchanneled overland flow) into pit from
pyi<;tinn hurlrnnpnlnnir^l and wpathp
nonchanneled overland flow) into pit from
existing hydrogeological and weather data
(i.e., water table gradient, aquifer hy-
draulic characteristics, direct surface
non
exi
draulic characteristics, dire
runoff, precipitation, etc.)
c. Estimate pollutant loading into pit from
above data
Sampling method
a. Install weirs or flumes to measure pit
inflow from discrete sources described
above
b. Install precipitation gages and evapora-
tion pans in the area of the pit
c. Install continuous recording flow meters
on pit discharge lines
d. Survey water surface area and install
staff gage to determine change in pit
storage
e. Collect pit water samples at various
depths and representative water samples
from discrete sources for chemical
analysis described for sedimentation
ponds above
1. Compile and review
existing data on dis-
crete and diffuse pit
water sources
2, Collect small number of
pit water samples to be
submitted for complete
chemical, biochemical,
and biological analyses;
submit subsequent samples
of same for partial
analysis focusing on
probable pollutants in
the pit water
3. Sample solid materials
at bottom of pit water 2. Operational
for nitrogen forms, trace
elements, TOC, etc. on
saturated extract
1. Labor
a. Compile and review pit
water quality data
(3 days): $180
b. Monitor equipment instal-
lation: $40/day
c. Quality control sample
handling, preparation,
col 1ection, etc.:
SB/sample
d. Field check of water
quality: $2.50/sample
a. Chemical analysis:
$2/sample
b. Field transportation:
$2/sample
c. Packing, air freight, etc.
for water quality samples:
$10/set, 1 to 3 samples
d. Bottles, labels, chemi-
cals: $2.50/sample
Define ground-
water usage
Define water usage
for mining activities
Determine location of
groundwater supply
wells
1. Nonsampling method
a. Interview mine operator or State engineer
to determine water usage for mine
activities
Compile and review
data on locations and
specifications for water
supply wells
1. Labor
a. Compile and review water
supply data and calculate
well pumpage (7 days):
$280
-------
TABLE B-2 (continued)
TEMPO monitoring
steps3 Monitoring needs
Define ground-
water usage
(continued)
Define hydro- 1. Determine geologic
geologic framework, location,
situation areal distribution,
Alternative monitoring
approaches
b. Review water well completion records for
yields, capacity, location, and aquifers
utilized
c. Determine well output from power consump-
tion records using calculated power con-
sumption versus discharge relationships
1. Nonsampling method
a. Compile available hydrogeologic data from
Prel iminary
recommendations
2. Determine well pumpage
from discharge versus
power consumption
1. Compile and review avail-
able hydrogeologic data
for source area (sedimen-
Monitoring costs
2. Operational
a. Field transportation-
$0.17/mile
3. Capital
a. None
1. Labor
a. Compile and review hydro-
interaction of aqui-
fers, and direction
and flow velocities
mine operators, adjoining mine operators,
U.S. Geological Survey, State agencies,
private consultants, and local drillers
2. Sampling method
a. Measure water levels and pump test well
in vicinity of source area (sedimentation
ponds)
b. Install new monitor wells near source area
required by data gaps
c. Determine aquifer properties (T and S)
from pumping tests
d. Install piezometer clusters in uppermost
aquifer near source area to determine
vertical hydraulic gradient and inter-
aquifer leakage
e. Develop water-level contour maps or piezo-
metric maps and well hydrographs based on
measured data
tation pond) and regional
system
Conduct aquifer tests on
existing wells and field
check water quality
Install monitor wells,
collect geological data
on penetrated formations,
and pump test new wells
near source so that the
potentiometric surface
can be defined by water
level data
Install piezometer clus-
ter near source area to
determine interaquifer
leakage and vertical
hydraulic gradient
geologic data (2 weeks):
$600
b. Sample existing wells-
$5/hr
c. Drilling labor and super-
vision, new monitor wells-
$93/hr
d. Pumping tests (3 persons):
$140/day
e. Drill site geologist:
$7/hr
f. Piezometer installation:
S30/site
g. Sample handling, quality
control, laboratory prepa-
ration: SB/sample
h. Field checks of water
quality: S2.50/sample
2. Operation
a. Chemical analysis:
5200/sample
b. Packing and air freight
for water quality sam-
ples: $25/set, 4 to 8
samples
c. Field transportation:
$2/sample
d. Soil analysis (cation ex-
change, soluble salts,
particle size): $64/sample
-------
TABLE B-2 (continued)
TEMPO monitoring
steps3 Monitoring needs
Define hydrogeo-
logic situation
(cont i nued )
Alternative monitoring
approaches
Preliminary
recommendations
Monitoring costs
e. Pump test (equipment
rental and operation):
$3,000/test
O1
Study existing
groundwater
quality
1. Determine chemical
quality of ground-
water (regionally and
site specific)
2. Characterize concen-
tration levels and
time trends of pol-
tants entering
groundwater system
based on upgradient
and downgradient
wells
1. Nonsampling method
a. Compile and review existing water quality
data
b. Construct isopleth maps, trilinear dia-
grams, and chemical hydrograms from above
data
2. Sampling method
a. Utilize existing and new monitor wells
installed to characterize hydrogeologic
framework for sample collection
b. Analyze samples for major inorganics,
trace constituents, organics, microorga-
nisms (see "identify potential pollu-
tants," sampling method (f), (g), (h), and
(i) above for complete analysis, alterna-
tive sampling procedures, and timing of
sample collection)
f. Field check water quality:
$2.50/sample
3. Capital
a. Piezometers: $15 each
b. Hardware and supplies for
monitor well completion:
$15/kit
c. Field kit (water quality
analysis): $700
d. Bailer, storage chest: $50
e. Bottles, labels, field
notebooks, chemicals,
etc.: $2.50/sample
f. Water-level sounder: $200
1, Compile, review, and
develop existing ground-
water quality data
2. Collect groundwater sam-
ples from existing and
new monitor wells (uti-
lize submers.ible pumps)
3. Analyze samples using
system described in
"identify potential pol-
lutants," sampling method
part (f), and delineate
pollutants which exceed
recommended limits
4. Conduct field tests for
pH, EC, DO, nitrate, and
chloride and collect
samples for laboratory
analyses when marked
changes occur between
field checks
1. Labor
a. Compile, review, and de-
velop water quality data
(2 weeks): $600
b. Sample existing wells:
$40/day
c. Drilling labor and super-
vision for new monitor
wells: $93/day
d. Drill site geologist:
$7/hr
e. Sample handling, quality
control, laboratory
preparation: $5/sample
2. Operation
a. Submersible pump: $30/site
b. Chemical analysis:
$200/sample
-------
TABLE B-2 (continued)
TEMPO monitoring
steps3 Monitoring needs
Study existing
groundwater
quality
(continued)
Alternative monitoring
approaches
Prel iminary
recommendations Monitoring costs
c. Air freight, packing for
water quality samples:
$25/set, 4 to 8 samples
d. Field transportation:
$2.50/sample
3. Capital
a. Field kit and storage
chest: $730
b. Bailer: $20
10
c. Bottles, labels, chemi-
cals: $2.50/sample
d. Submersible pump and gene-
rator: $1,200
e. pH meter: $325
f. EC bridge: $375
g. DO meter: $400
Evaluate infil- 1. Determine quantity of 1. Nonsarnpling method
tration potential
infiltration water
from the source
(sedimentation ponds)
a. Define a water budget for the source based
on available records from the mine opera-
tor, and meteorological data (i.e., in-
flow rates from all mine sources, pond
outflow rates, rainfall-evaporation rates,
change in pond storage)
2. Sampling method
a. Determine infiltration by conducting
seepage meter measurements in the source
area
1. Utilize water budget
approach to determine
infiltration at source
2. Use existing gaging sta-
tions supplemented by
installation of recording
flow meters, automatic
stage recorders, or staff
gages
3. Install rain gages and
evaporation pans
1. Labor
a. Inventorying sedimentation
pond sources (2 weeks):
$400
b. Installation of monitoring
equipment: $5/hr
c. Rain gage and evaporation
pan installation: $5/hr
2. Operation
a. Field transportation:
$0.17/mile
b. Field measurements and
equipment maintenance:
$5/hr
3. Capital
a. Weather station (evapora-
tion and precipitation):
$800 each
b. Flow meter: $40 each
-------
TABLE B-2 (continued;
TEMPO monitoring
steps3
Monitoring needs
Alternative monitoring
approaches
Prelimi nary
recommendations
Monitoring costs
Evaluate infiltra-
tion potential
C cont inued)
c. Automatic stage recorder:
$375 each
d. Staff gage: $50 each
Evaluate mobility
in the vadose
zone
Determine attenuation
and migration of
pollutants within
the vadose zone
00
1. Nonsampling method
a. Construct a table (matrix) comprising
specific pollutants (columns) and attenu-
ating factors (rows) and determine or
estimate from available chemical or bio-
chemical data pollutant attenuation for
each matrix point in the table by evalu-
ating effects of oxidation reduction,
sorption, chemical precipitation, buffer-
ing, dilution, filtration, volatilization,
biological degradation, and assimilation
b. Analyze existing monitor well cutting to
characterize cation exchange, pH, Eh, par-
ticle size distribution, precipitation, or
staining on aquifer matrix or materials
which comprise the vadose zone
2. Sampling method
a. Analyze, as (b) above, auger or core
samples from the vadose zone in source
area
b. Install suction lysimeter for sampling
unsaturated flows
c. Develop monitor wells in perched water
tables where indicated by neutron logging
d. Analyze water samples from (b) or (c)
above for major inorganics, trace consti-
tuents, and organics (see "identify po-
tential pollutants," sampling method part
(f) above]
1. Construct table (matrix)
of attenuation factors
versus specific pollu-
tants using available
data
2. Install monitor wells in
uppermost aquifer below
source (sedimentation
pond)
3. Install three sets of
tensiometers and moisture
blocks at base of pond
and along the outflow
channel
4. Install suction cups at
base of pond and along
outflow channel alluvium
5. Collect soil samples for
laboratory analysis of
pollutants and chemical
characteristics when in-
stalling tensiometers;
collect additional auger
or core samples, if
necessary
6. Install monitor well in
perched groundwater body
as indicated by neutron
logging
7. Analyze groundwater and
soil samples as detailed
in text
1. Labor
a. Evaluation of attenuation
factors versus specific
pollutants (3 weeks): $900
b. Drilling labor and super-
vision for monitor wells:
$93/hr
c. Drill site geologist:
$7/hr
d. Sample handling, quality
control, laboratory prep-
aration: $5/sample
e. Tensiometer installation:
$30/site
f. Suction cup installation:
$30/site
g. Neutron logging: $50/site
2. Operation
a. Chemical analysis:
$200/sample
b. Soil analysis (cation ex-
change, soluble salts,
particle size): $64/sample
c. Air freight, packing:
$25/set, 4 to 8 samples
d. Field transportation:
$2/sample
3. Capital
a. Neutron logger and gene-
rator: $15,000
b. Hardware and supplies to
complete monitor well:
$15/ft
c. Bailer, storage chest: $50
-------
TABLE B-2 (continued)
TEMPO monitoring
steps3
Monitoring needs
Alternative monitoring
approaches
Preliminary
recommendations
Monitoring costs
Evaluate mobility
in the vadose
zone (continued)
d. Bottles, labels, chemi-
cals, etc: $2.50/sample
e. Tensiometers: $20 each
f. Moisture blocks: $5 each
g. Moisture meter: $150
h. Suction cups: $4 each
Evaluate attenu- 1. Determine attenuation 1. Nonsampling method
ation of pollu-
tants in the
saturated zone
and migration charac-
teristics of pollu-
tants within aquifers
underlying source
(sedimentation ponds)
i-D
a. Construct a table (matrix) of attenuating
mechanisms versus pollutants as was done
in the previous monitoring step for the
saturated zone to show concentration of
the different pollutants which should be
monitored
2. Sampling method
a. Determine aquifer exchange capacity from
analysis of monitor well cuttings
b. Characterize Eh and pH of groundwater
from field analysis
c. Initiate tracer studies to estimate
spread and attenuation of pollutants
d. Install piezometer clusters in uppermost
aquifer below source area to determine
vertical movement of pollutants
e. Concentrate monitoring effort on pollu-
tants which pass through the vadose zone
characterized in the two preceding moni-
toring steps
1. Construct attenuation
mechanism versus pollu-
tant mataix using avail-
able data
2. Monitor existing wells
and install and sample
vertical distribution of
groundwater quality using
piezometer clusters near
source
3. Conduct tracer study if
tracer breakthrough time
is estimated to be short
1. Labor
a. Construct pollutant atten-
uation matrix (3 weeks):
$900
b. Piezometer installation:
$30/site
c. Sample handling, quality
control, laboratory prep-
aration: $5/sample
d. Tracer study, if required:
$7/hr
e. Sample wells: $5/hr
2. Operation
a. Chemical analysis:
$200/sample
b. Air freight, packing, etc:
$25/set, 4 to 8 samples
c. Field transportation:
$2/sample
3. Capital
a. Piezometers: $15 each
b. Well hardware for piezome-
ter cluster: $5/ft
c. Bottles, labels, chemi-
cals, etc.: $2.50/sample
d. Bailer, storage chest: $50
e. Portable pump and genera-
tor: $1,200
-------
TABLE B-3. SUMMARY OF PRELIMINARY MONITORING DESIGN FOR MISCELLANEOUS ACTIVE MINE SOURCES
TEMPO monitoring
steps9
Monitoring needs
Alternative monitoring
approaches
Prel imi nary
recommendations
Monitoring costs
Identify poten-
tial pollutants
(explosives)
O
O
Identify poten-
tial pollutants
(nine solid
wastes)
1. Characterize amount
of residual ammonium-
nitrate and fuel oil
from explosives
2. Evaluate spillage of
these materials dur-
ing handling and
blasting operations
1. Characterize amount
of potential pollu-
tants in premining
construction mate-
rials (scrap lumber,
metals, cement, etc.)
and mining waste
(disposable contain-
ers, worn out parts,
etc.)
1. Nonsampling method
a. Inventory records kept in compliance with
the Surface Mining Control and Reclamation
Act, i.e., type and weight of explosives,
number of holes and spacing, location,
etc.
b. Interview mine personnel regarding spills
and cleanup measures for explosives
2. Sampling method
a. Sample overburden and coal prior to and
following blasting to characterize
explosive-related pollutants
b. Analyze samples for nitrogen forms, fuel
oil, and TOC
1. Nonsampling method 1.
a. Estimate weight and inventory waste
delivered to disposal site by stationing
an inspector at the site or by reviewing
mine construction and waste materials 2.
2. Sampling method
a. Sample leachate from solid waste disposal
site by taking grab samples of leachate 3.
at base of waste disposal pile
b. Install suction-cup lysimeters to sample
water in vadose zone, sample wells in
perched water layers, or saturated zone
below or near the disposal area (for de-
tails see monitoring steps, Evaluate
Mobility in the Vadose Zone, and Evaluate
Attenuation of Pollutants in the Saturated
Zone, for sedimentation ponds, Section 3)
c. Grab sampling water inflow and discharge
from disposal site to determine quality of
source and leachate waters from the site
1. Inventory mining records 1. Labor
Refer to analysis per-
formed in monitoring pit
water (Section 3) to
determine if further
sampling of explosive-
related pollutants is
regui red
Inventory mine construc-
tion materials and infre-
quently (4 to 6 months)
spot check disposal site
Collect grab sample of
surface runoff of "land-
fill discharge after
precipitation event
Analyze grab sample com-
pletely (see Monitoring
of Sedimentation Ponds
for complete chemical
chemical analysis,
Table B-2)
a. Inventory mine records
(1 week): $200
b. Sample handling, quality
control, laboratory prep-
aration (if samples are
taken): $10/sample
2. Operation
a. Chemical analysis (if
required): $100/sample
b. Field transportation:
$2/sample
3. Capital
a. Sample containers, labels,
chemicals, etc. (if re-
quired): $2.50/sample
1. Labor
a. Inventory mine construc-
tion and other solid
wastes (1 week): $200
b. Sample handling, quality
control, laboratory prep-
aration: $5/sample
2. Operation
a. Chemical analysis:
$200/sample
b. Field transportation:
$2/sample
3. Capital
A. Miscellaneous supplies,
bottles, labels, etc.:
$2.50/sample
a Subsequent monitoring steps for solid or liquid miscellaneous mine wastes are given in Tables B-l and B-2, respectively
-------
TABLE B-3 (continued)
TEMPO monitoring
steps3
Monitoring needs
Alternative monitoring
approaches
Preliminary
recommendations
Monitoring costs
Identify poten-
tial pollutants
(mine solid
wastes) (continued)
d. Samples would be analyzed completely (see
Section 3, Identify Potential Pollutants--
Sedimentation Ponds) until pollutants are
characterized
Identify poten-
tial pollutants
(liquid shop
waste)
1. Characterize poten- 1. Nonsampling method
tial pollutants in
oils, 1ubr icants,
gasoline, wash water,
soap, and other sub-
stances incorporated
in the liquid shop
wastes
a. Interview mine personnel to determine
type and quantities of liquid wastes pro-
duced, wash areas, soaps, quality of
wash water
b. Observe sources of liquid shop wastes
in field
2. Sampling method
a. Collect samples from lysimeters, or wells
near shop areas
b. Submit samples for complete chemical
analysis
(For analytical tests see Section 3, Monitoring
Design for Mine Sources)
1. Interview mine personnel
to determine what liquid
shop wastes will be
produced
2. Field check shop liquid
wastes and collect grab
sample if necessary
1. Labor
a. Inventory mine personnel
(1 week): $300
b. Sample handling, quality
control: SB/sample
2. Operation
a. Field transportation:
$0.17/mile
b. Chemical analysis (if
required): $200/sample
3. Capital
a. Miscellaneous supplies,
bottles, etc: $2.50/sample
Identify poten-
tial pollutants
(spills and
leaks)
Characterize quan-
tities and chemical
quality of substances
stored and trans-
ported on the lease
area and thereby sub-
ject to spillage or
leakage
^onsanpling method
a. Interview mine personnel to determine
quantities and transportation require-
ments of substances stored on the lease
area
b. Review accident reports and records of
previous spills or leaks
c. Field check storage locations and trans-
portation routes for potential pollutants
resulting from spills or leaks
1. Utilize nonsampling
method described in
Table B-2, Alternative
Monitoring Approaches for
a Preliminary Monitoring
Desi gn
1. Labor
a. Inventory mine accident
reports and interview mine
personnel (1 week): $200
2. Operation
a. Field transportation:
$0.17/mile
3. Capital: None
Identify poten-
tial pollutants
(solid waste for
road construction
and liquids used
for dust suppres-
sion)
1. Characterize poten-
tial pollutants in
leachate from solid
waste for road
construction
1. Nonsampling method
a. Interview mine personnel to determine mine
road construction materials and dust sup-
pression programs
b. Pollutants in solid waste (overburden,
mine spoils, etc.) used for road con-
struction and fluids (pit water) used for
dust suppression are discussed in Sections
2 and 3, respectively
Conduct interviews with
mine personnel to deter-
mine locations, con-
struction materials, and
dust suppression programs
Use data gathered in
parallel monitoring steps
(for stockpiles and mine
water sources) to charac-
terize potential pollu-
tants in mine road
leachate
1. Labor
a. Interview mine personnel
(3 days): S120
2. Operation
a. Field transportation:
$0.17/mile
3. Capital: None
-------
TABLE B-3 (continued)
TEMPO monitoring
steps3
Identify poten-
tial pol lut ants
(septic tanks)
Monitoring needs
1. Characterize pollu-
tants found as major
inorganics, trace
constituents, orga-
nics, and microorga-
nisms in septic tank
eff 1 uent
Alternative monitoring
approaches
1. Nonsampling method
a. Inventory all sources discharging to the
septic tank and estimate the quantities
and quality of fluids involved
b. Review engineering design for septic
Prel imi nary
recommendations
1. Inventory all sources 1.
discharging to septic
tank, data on engineering
design, leach field soils,
and percolation rates
2. Install automatic corn-
Monitoring costs
Labor
a. Review septic tank engi-
neering data (1 week):
$200
t. Install sampling equip-
o
ro
tanks and leach field characteristics
c. Compile soil and percolation information
for leach field area
2. Sampling method
a. Sample septic tank effluent by installing
automatic composite sampler
b. Sample leach field by installing network
of shallow wells or suction-cup lysimeters
c. Analyze first few samples completely
(see text) and subsequently focus analysis
on constituents found to be in excess
posite sampler at tank
discharge point (grab
samples could also be
taken here)
3. Install network of shal-
low monitoring wells in
the leach field
4. Collect and analyze
samples as discussed in
the text
c. Sample handling quality
control, laboratory prep-
aration: SB/sample
d. Install shallow wells in
leach field: $5/hr
2. Operation
a. Chemical analysis:
$200/sample
b. Field transportation,
equipment maintenance:
$2/sample
c. Air freight, packing, etc.
for water quality samples:
SlO/set, 1 to 3 samples
3. Capital
a. Automatic sampler: $600
b. Leach field well hardware:
$10/ft
c. Sample bottles, labels,
miscellaneous supplies:
$2.50/sample
d. Bailer: $20
e. Power hole digger: $300
Identify poten-
tial pollutants
(oxidation ponds)
1. Characterize pollu-
tants found as major
inorganics, trace
constituents, orga-
nics, and microorga-
nisms in oxidation
pond effluent
1. Nonsampling method
a. Inventory all sources of discharge to
oxidation ponds
b. Review engineering design (e.g., depth,
surface area, lining, etc.) and method of
operation (high-rate aerobic, facultative,
or mechanically aerated pond)
Inventory all sources of
discharge to oxidation
ponds, engineering speci-
fications for ponds, and
method of operation
Install water sampling
and flow measuring equip-
ment at inlet and dis-
charge points
1. Labor
Review method of operation
and engineering specifica-
tions of oxidation ponds:
(3 days): $120
Installation of sampling
equipment: $40/day
-------
TABLE B-3 (continued)
TEMPO monitoring
steps3
Identify poten-
tial pollutants
(oxidation ponds)
(continued)
Alternative monitoring
Monitoring needs approaches
2. Sampl i ng method
a. Collect samples of sources of discharge to
ponds, pond effluent, and at various
points within this pond
Preliminary
recommendations Monitoring costs
c. Field check water quality:
$2. 507 sample
d. Sample handling, quality
control, laboratory prep-
aration: $5/sample
o
GO
b. Utilize alternative sampling techniques
(grab, automatic composite, or discrete,
etc.)
c. Conduct field analysis for water quality
d. Sample benthic solids in ponds
2. Operation
a. Chemical analysis:
S200/sample
b. Field transportation:
$2/sample
c. Air freight, packing, etc.
for water quality samples:
$10/set, 1 to 3 samples
3. Capital
a. Automatic sampler: $600
b. Flow meter: $40
c. Field kit, storage chest:
$730
d. Bottles, labels, chemi-
cals: $2.50/s ample
Identify poten-
tial pollutants
(package plant)
Characterize package
plant water quality
(i.e., organics,
BOD, COD, DOC, TOC;
microorganisms,
viruses, total and
fecal coliform,
microscopic animals;
major and trace
i norgan ics)
1. Nonsampling method
a. Obtain plant and surge tank specification
from mine manager
b. Inventory sources to plant including shop
waste, portable toilets, and anticipated
loading rate
c. Compile copies of quality control data
and determine analytical techniques
utilized
2. Sampling method
a. Install composite and discrete automatic
samplers at plant inflow and outflow
ports, and flow meter on incoming lines
b. Collect discrete samples at 2-hour inter-
vals until trends are established for BOD
and coliform and 6-hour intervals for com-
plete analysis and source characterization
1. Obtain available infor-
mation on package plant
design, surge tank, and
chlorinator design and
operation
2. Interview mine personnel
to determine plant usage,
loading rates, sewer
line distribution and
drain line to sedimenta-
tion pond, etc.
3. Install automatic dis-
crete sampler at inlet
and discharge ports
4. Install 24-hour compos-
ite sampler at the
discharge ports
1. Labor
a. Interview personnel and
review package plant
engineering data (3 days):
$120
b. Sampling equipment
installation: $40/day
c. Quality control, sample
handling, laboratory prep-
aration: SS/sample
2. Operation
a. Chemical analysis:
$200/sample
b. Field transportation:
$2/sample
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TABLE B-3 (continued'
TEMPO monitoring
steps3 Monitoring needs
Identify poten-
tial pollutants
(package plant)
(continued)
Alternative monitoring
approaches
c. Install 24-hour composite sampler for
monthly sample collection
d. Install discrete sampler at discharge
Preliminary
recommendations
5. Install discrete sampler
in discharge point to
sedimentation pond
Monitoring costs
c. Air freight, packing, etc.
for water quality samples:
$25/set, 4 to P samples
point to sedimentation pond
e. Analysis of samples will vary from deter-
mining BOD and coliform to complete
analysis as described in text
6. Samples will be collected 3. Capital
to characterize coliform
and BOD trends and at
less frequent intervals
for complete chemical
and biochemical analysis
a. Automatic sampler (3X):
$1,800
b. Bottles, labels, chemi-
cals: $2.50/sample
c. Flow meter: $40
Identify poten-
tial pollutants
(sludge)
1. Characterize organics
including polychlori-
nated biphenols and
other organic toxins
filtered into sewer
system, MLSS, and
major and trace
i norganics
2.
Estimate quantity of
sludge produced
1. Nonsampling method
a. Estimate volume of sludge produced each
time aeration basin is pumped, record
pumping frequency
b. Characterize sources of wastewater through
collaboration with monitoring of sewage
treatment and package plants
c. Compile data on sludge disposal locations
and methods
2. Sampling method
a.- Sample sludge via special brass sampler or
by pole and bottle method
b. Grab sample sludge at beginning, during,
and at end of pumping periods
c. Sample soil piles or spreading areas used
for sludge disposal
d. Analyze samples as described in text
Corroborate sludge moni-
toring effort with sewage
treatment and package
plant studies
Collect sludge samples
at package plant via
pole and bottle sampler
and grab samples during
pumping periods
1. Labor
a. Collaborate data on sludge
production (2 days): $80
b. Quality control, sample
handling, laboratory prep-
aration: $5/sample
2. Operation
a. Chemical analysis:
$140/sample
b. Field transportation:
$2/sample
c. Air freight, packing, mis-
cellaneous: $10/set, 1 to
3 samples
3. Capital
a. Pole and bottle sampler:
$10
b. Bottles, labels, chemi-
cals, etc.: $2.50/sample
-------
TECHNICAL REPORT DATA
(Please read Instructions on the reverse before completing)
1. REPORT NO.
EPA-600/7-80-nO
3. RECIPIENT'S ACCESSION>NO.
4. TITLE ANDSPBTITLE
GROUNDWATER QUALITY MONITORING OF WESTERN COAL STRIP
MINING: Preliminary Designs for Active Mine Sources
of Pollution
5. REPORT DATE
June 1980
6. PERFORMING ORGANIZATION CODE
7. AUTHOR(S)
Lome G. Everett, Edward W. Hoylman (editors)
8. PERFORMING ORGANIZATION REPORT NO.
GE79TMP-27
9. PERFORMING ORGANIZATION NAME AND ADDRESS
General Electric Company-TEMPO
Center for Advanced Studies
Santa Barbara, California 93102
10. PROGRAM ELEMENT NO.
11. CONTRACT/GRANT NO.
68-03-2449
12. SPONSORING AGENCY NAME AND ADDRESS
U.S. Environmental Protection Agency-Las Vegas, Nevada
Office of Research and Development
Environmental Monitoring Systems Laboratory
Las Vegas, Nevada 89114
13. TYPE OF REPORT AND PERIOD COVERED
14. SPONSORING AGENCY CODE
EPA/600/07
15. SUPPLEMENTARY NOTES
16. ABSTRACT
Three potential pollution source categories have been identified for Western
coal strip mines. These sources include mine stockpiles, mine waters, and miscel-
laneous active mine sources. TEMPO'S stepwise monitoring methodology (Todd et al.,
1976) is used to develop groundwater quality monitoring designs for each source
category. These designs include description of monitoring needs, alternative moni-
toring approaches, and preliminary recommendations. Generic and example case
studies are presented for stockpile and mine water sources. General case consider-
ations are given for miscellaneous sources. Unit cost estimates for the monitoring
designs, based on preliminary recommendations, are given in Appendix B.
7.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
b.lDENTIFIERS/OPEN ENDED TERMS
c. COSATI Field/Group
Groundwater
Groundwater quality
Waste management
Coal mining
Sanitary landfills
Strip mining wastes
Septic tanks
Groundwater movement
Monitor wells
Monitoring methodology
43F
44G
48A
68C
68D
91A
8. DISTRIBUTION STATEMENT
RELEASE TO PUBLIC
19.
(This Report)
21.
F PAGES
20. SECURITY CLASS (Thispage)
UNCLASSIFIED
22. PRICE
EPA Form 2220-1 (9-73)
•frU.S. GOVERNMENT PRINTING OFFICE: 1980-683-282/2238
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