oEPA
United States
Environmental Protection
Agency
Review of Peer-Reviewed
Documents on Treatment
Technologies Used at Mining
Waste Sites
August 2021
U.S. Environmental Protection Agency
Office of Superfund Remediation and Technology Innovation LP A DH:Z-H-d\J-\)UZ
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Notice/Disclaimer Statement
Under U.S. Environmental Protection Agency contract No. EP-C-11-036 through its Office of Research
and Development, an initial contractor, RTI, conducted the literature research under an approved Quality
Assurance Project Plan (Quality Assurance Identification Number L-300010-QP-1-0). Under EPA
Contract No. GS-10F-0309N, a second contractor, Skeo Solutions, Inc., conducted data analyses and
interpretation under a Quality Assurance Project Plan approved with U.S. Environmental Protection
Agency Office of Superfund Remediation and Technology Innovation. The primary authors of this
report are Michele Mahoney, U.S. EPA, Office of Land and Emergency Management, Office of
Superfund Remediation and Technology Innovation, Technology Innovation & Field Services Division,
and Barbara A. Butler, U.S. EPA, Center for Environmental Solutions and Emergency Response, Land
Remediation and Technology Division.
This review provides information about numerous technologies used in remediation of various mining
wastes from existing case studies. The data reported and/or summarized in sources referenced are
assumed to have been evaluated for quality by the reporting entity and has not been evaluated
independently by EPA. However, calculated values using the secondary data have been verified to have
been accurately calculated. Any mention of trade names, products, or services does not imply an
endorsement by the U.S. Government or the U.S. Environmental Protection Agency. The EPA does not
endorse any commercial products, services, or enterprises. This report has undergone U.S.
Environmental Protection Agency and external review by subject matter experts and has been approved
for publication.
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Foreword
The U.S. Environmental Protection Agency (EPA) is charged by Congress with protecting the
Nation's land, air, and water resources. Under a mandate of national environmental laws, the
Agency strives to formulate and implement actions leading to a compatible balance between
human activities and the ability of natural systems to support and nurture life. To meet this
mandate, EPA's research program is providing data and technical support for solving
environmental problems today and building a science knowledge base necessary to manage our
ecological resources wisely, understand how pollutants affect our health, and prevent or reduce
environmental risks in the future.
The Office of Superfund Remediation and Technology Innovation (OSRTI) within the Office of
Land and Emergency Management (OLEM) administers the Superfund Program, the federal
government's program to clean up the nation's uncontrolled hazardous waste sites. OSRTI is
committed to ensuring that the hazardous waste sites on the National Priorities List are cleaned
up to protect the environment and the health of all Americans. The Technology Innovation and
Field Services Division (TIFSD) within OSRTI advocates for the innovative use of technologies
to assess and clean up Superfund sites as well as other contaminated sites. TIFSD provides
national leadership for the delivery of analytical, science-based services for regions and states,
and supports the use of technologies that are safe, effective and economically feasible. This type
of valuable technical assistance and research supports advancements in the field and aids in
environmental emergency responses.
Documenting studies of treatment technologies at Superfund and other sites is important in
providing an understanding of how these technologies remove contaminants and can aid a reader,
such as a site manager, in determining if the technology would be effective under the conditions
at their site of interest. This report is published and made available by US EPA's Office of Land
and Emergency Management Office of Superfund Remediation and Technology Innovation to
assist readers in the remediation community in understanding the capabilities and limitations of
remedial technologies employed at mining sites.
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Contents
Notice/Disclaimer Statement ii
Foreword iii
Contents iv
Tables x
Acronyms and Abbreviations xv
Acknowledgments xvii
Conversion Factors xviii
1 Introduction 1-1
1.1 Methodology 1-1
1.1.1 Scientific Literature Review Approach 1-1
1.1.2 Data Evaluation Procedures 1-3
1.2 Limitations 1-4
2 Use of this Review 2-1
2.1 References 2-1
3 Biochemical Reactors 3-1
3.1 Case Studies Evaluated 3-2
3.2 Constraints 3-5
3.3 Treatable Contaminants 3-6
3.3.1 Anaerobic, Solid Substrate BCRs 3-6
3.3.2 Anaerobic, Liquid BCRs 3-6
3.3.3 Aerobic, Solid Substrate BCRs 3-6
3.4 Capability - Anaerobic, Solid Substrate 3-6
3.4.1 Ranges of Applicability 3-6
3.4.2 Average Influent and Effluent Concentrations 3-9
3.4.3 Removal Efficiency 3-12
3.4.4 Flow Rates 3-14
3.5 Capability - Anaerobic, Liquid Substrate 3-15
3.5.1 Ranges of Applicability 3-15
3.5.2 Average Influent and Effluent Concentrations 3-17
3.5.3 Removal Efficiency 3-18
3.5.4 Flow Rates 3-19
iv
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3.6 Capability - Aerobic, Solid Substrate 3-19
3.6.1 Ranges of Applicability 3-20
3.6.2 Average Influent and Effluent Concentrations 3-20
3.6.3 Removal Efficiency 3-20
3.6.4 Flow Rates 3-20
3.7 Costs 3-20
3.8 Lessons Learned 3-20
3.9 References 3-22
3.9.1 Case Study References 3-22
3.9.2 General BCR References 3-23
4 Caps and Covers 4-1
4.1 Case Studies Evaluated 4-1
4.2 Constraints 4-2
4.3 Treatable Contaminants 4-2
4.4 Capability 4-3
4.4.1 Ranges of Applicability 4-3
4.4.2 Average Pre-Treatment and Post-Treatment Concentrations 4-4
4.4.3 Percentage Reduction 4-6
4.4.4 Flow Rates 4-7
4.5 Costs 4-8
4.6 Lessons Learned 4-8
4.7 References 4-8
4.7.1 Case Study References 4-8
4.7.2 General Capping References 4-9
5 Neutralization and Chemical Precipitation 5-1
5.1 Case Studies Evaluated 5-1
5.2 Constraints 5-3
5.3 Treatable Contaminants 5-3
5.4 Capability - Active 5-3
5.4.1 Ranges of Applicability 5-4
5.4.2 Average Influent and Effluent Concentrations 5-5
5.4.3 Average Mass Removed 5-9
5.4.4 Removal Efficiency 5-9
v
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5.4.5 Flow Rates 5-10
5.5 Capability - Semi-Passive Treatment 5-11
5.5.1 Ranges of Applicability 5-12
5.5.2 Average Influent and Effluent Concentrations 5-13
5.5.3 Removal Efficiency 5-14
5.5.4 Flow Rates 5-14
5.6 Capability - Passive Treatment 5-14
5.6.1 Ranges of Applicability 5-14
5.6.2 Average Influent and Effluent Concentrations 5-14
5.6.3 Removal Efficiency 5-16
5.6.4 Flow Rates 5-16
5.7 Costs 5-17
5.8 Lessons Learned 5-17
5.9 References 5-17
5.9.1 Case Study References 5-17
5.9.2 General Neutralization Chemical Precipitation Treatment References 5-18
6 Chemical Stabilization 6-1
6.1 Case Studies Evaluated 6-1
6.2 Constraints 6-2
6.3 Treatable Contaminants 6-2
6.4 Capability 6-3
6.4.1 Ranges of Applicability 6-3
6.4.2 Average Leachate Concentrations from Untreated and Treated Cells of Waste Rock 6-6
6.4.3 Percent Reduction 6-9
6.4.4 Flow Rates 6-11
6.5 Costs 6-11
6.6 Lessons Learned 6-11
6.7 References 6-11
6.7.1 Case Study References 6-11
6.7.2 General Chemical Stabilization References 6-12
7 Constructed Wetlands 7-1
7.1 Case Studies Evaluated 7-1
7.2 Constraints 7-2
vi
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7.3 Treatable Contaminants 7-3
7.4 Capability - Anaerobic 7-3
7.4.1 Ranges of Applicability 7-3
7.4.2 Average Influent and Effluent Concentrations 7-3
7.4.3 Removal Efficiency 7-4
7.4.4 Flow Rates 7-4
7.5 Capability - Aerobic 7-4
7.5.1 Ranges of Applicability 7-4
7.5.2 Average Influent and Effluent Concentrations 7-5
7.5.3 Removal Efficiency 7-8
7.5.4 Flow Rates 7-9
7.6 Costs 7-9
7.7 Lessons Learned 7-9
7.8 References 7-10
7.8.1 Case Study References 7-10
7.8.2 General Constructed Wetlands References 7-10
8 In-Situ Treatment of Mine Pools and Pit Lakes 8-1
8.1 Case Studies Evaluated 8-1
8.2 Constraints 8-2
8.3 Treatable Contaminants 8-2
8.4 Capability - Pit Lakes 8-2
8.4.1 Ranges of Applicability 8-2
8.4.2 Average Pre-Treatment and Post-Treatment Concentrations 8-4
8.4.3 Removal Efficiency 8-4
8.4.4 Flow Rates 8-4
8.5 Capability - Mine Pools 8-5
8.5.1 Ranges of Applicability 8-5
8.5.2 Average Pre-Treatment and Post-Treatment Concentrations 8-6
8.5.3 Removal Efficiency 8-6
8.5.4 Flow Rates 8-7
8.6 Costs 8-7
8.7 Lessons Learned 8-7
8.8 References 8-7
vii
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8.8.1 Case Study References 8-7
8.8.2 General In Situ Treatment of Mine Pools and Pit Lakes References 8-8
9 Permeable Reactive Barriers 9-1
9.1 Case Studies Evaluated 9-1
9.2 Constraints 9-2
9.3 Treatable Contaminants 9-2
9.4 Capability 9-2
9.4.1 Ranges of Applicability 9-3
9.4.2 Average Influent and Effluent Concentrations 9-4
9.4.3 Removal Efficiencies 9-6
9.4.4 Flow Rates 9-7
9.5 Costs 9-7
9.6 Lessons Learned 9-7
9.7 References 9-8
9.7.1 Case Study References 9-8
9.7.2 General Capping References 9-8
10 T reatment T rains 10-1
10.1 Case Studies Evaluated 10-1
10.2 Constraints 10-7
10.3 Treatable Contaminants (All Configurations) 10-7
10.4 Capability - Treatment Trains (All Configurations) 10-8
10.5 Capability - Anaerobic BCR with Pre-and/or Post-Treatment 10-8
10.5.1 Ranges of Applicability 10-8
10.5.2 Average Influent and Effluent Concentrations 10-11
10.5.3 Removal Efficiency 10-16
10.5.4 Flow Rates 10-18
10.6 Capability - Constructed Wetlands with Capping and/or Pre- or Post-Treatment 10-19
10.6.1 Ranges of Applicability 10-19
10.6.2 Average Pre- and Post-Treatment Concentrations 10-21
10.6.3 Removal Efficiency 10-23
10.6.4 Flow Rates 10-25
10.7 Capability - Alkaline Precipitation with Pre- and/or Post-Treatment 10-25
10.7.1 Ranges of Applicability 10-25
viii
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10.7.2 Average Pre- and Post-Treatment Concentrations 10-25
10.7.3 Removal Efficiency 10-26
10.7.4 Flow Rates 10-26
10.8 Costs 10-26
10.9 Lessons Learned 10-26
10.10 References 10-27
10.10.1 Case Study References 10-27
Appendix A: Biochemical Reactors Data Tables A-l
Appendix B: Caps and Covers Data Tables B-l
Appendix C: Neutralization and Chemical Precipitation Data Tables C-l
Appendix D: Constructed Wetlands Data Tables D-l
Appendix E: Treatment Trains Data Tables E-l
ix
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Tables
Table 3-1: Bioreactor Case Study Sites 3-2
Table 3-2: Maximum Influent and Corresponding Effluent Concentrations 3-7
Table 3-3: Minimum Influent and Corresponding Effluent Concentrations 3-7
Table 3-4: Maximum Average Influent Concentration Treated 3-9
Table 3-5: Minimum Average Influent Concentration Treated 3-10
Table 3-6: Maximum Average Effluent Concentration Attained 3-10
Table 3-7: Minimum Average Effluent Concentration Attained 3-11
Table 3-8: Maximum Removal Efficiencies 3-13
Table 3-9: Minimum Removal Efficiencies 3-13
Table 3-10: Flow Rate - Anaerobic, Solid Substrate 3-14
Table 3-11: Maximum Influent and Corresponding Effluent Concentrations - Leviathan 3-16
Table 3-12: Minimum Influent and Corresponding Effluent Concentrations - Leviathan 3-16
Table 3-13: Maximum Influent and Corresponding Effluent Concentrations - Keno Hill 3-17
Table 3-14: Minimum Influent and Corresponding Effluent Concentrations - Keno Hill 3-17
Table 3-15: Maximum Removal Efficiencies - Leviathan 3-18
Table 3-16: Minimum Removal Efficiencies - Leviathan 3-18
Table 3-17: Average Removal Efficiencies - Keno Hill 3-19
Table 4-1: Caps and Covers Case Study Sites 4-1
Table 4-2: Concentration Range Pre- and Post-Capping - Kristineberg Mine 4-3
Table 4-3: Maximum Average Pre-Capping Leachate and Post-Capping Leachate Concentration Range
(1996-1998 - 1999-2004) - Dunka Mine 4-4
Table 4-4: Minimum Average Pre-Capping Leachate and Post-Capping Leachate Concentrations (1996-
1998) - Dunka Mine 4-4
Table 4-5: Savage River Mine - Percent Total Sulfur in Waste Rock, Pre-Cover, Post-Cover and with No
Cover Within The B-Dump 4-5
Table 4-6: Maximum and Minimum Percentage Reduction 4-6
Table 4-7 Average Flow 4-7
Table 5-1: Neutralization and Chemical Precipitation Case Study Sites 5-2
Table 5-2: Maximum Influent and Corresponding Effluent Concentrations - Active Treatment 5-4
Table 5-3: Minimum Influent and Corresponding Effluent Concentrations - Active Treatment 5-4
Table 5-4: Maximum Average Influent Concentration Treated - Active Treatment 5-6
Table 5-5: Minimum Average Influent Concentration Treated - Active Treatment 5-6
x
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Table 5-6: Maximum Average Effluent Concentration Attained - Active Treatment 5-7
Table 5-7: Minimum Average Effluent Concentration Attained - Active Treatment 5-8
Table 5-8: Maximum Removal Efficiencies - Active Treatment 5-9
Table 5-9: Minimum Removal Efficiencies - Active Treatment 5-10
Table 5-10: Flow Rate - Active Treatment 5-10
Table 5-11: Maximum Influent and Corresponding Effluent Concentrations - Semi-Passive Treatment...5-
12
Table 5-12: Minimum Influent and Corresponding Effluent Concentrations - Semi-Passive Treatment5-12
Table 5-13: Average Influent Concentration Treated - Semi-Passive Treatment 5-13
Table 5-14: Removal Efficiencies - Semi-Passive Treatment 5-14
Table 5-15: Average Influent and Effluent Concentrations - Tanks 1 and 2 5-15
Table 5-16: Removal Efficiencies - Tanks 1 and 2 5-16
Table 6-1: Chemical Stabilization Case Study Site 6-1
Table 6-2: Average Leachate Concentration Ranges from Treated and Untreated Cells of Waste Rock-
All Treatment Types 6-4
Table 6-3: Average Leachate Concentrations from Treated and Untreated Cells of Waste Rock - All
Treatment Types 6-7
Table 6-4: Percent Reduction - All Treatment Types 6-9
Table 7-1: Constructed Wetlands Case Study Sites 7-2
Table 7-2: Average Influent Concentration Treated 7-3
Table 7-3: Average Removal Efficiencies 7-4
Table 7-4: Maximum and Minimum Influent and Corresponding Effluent Concentrations 7-5
Table 7-5: Maximum Average Influent Concentration Treated 7-5
Table 7-6: Minimum Average Influent Concentration Treated 7-6
Table 7-7: Maximum Average Effluent Concentration Attained 7-6
Table 7-8: Minimum Average Effluent Concentration Attained 7-7
Table 7-9: Maximum Average Removal Efficiencies 7-8
Table 7-10: Minimum Average Removal Efficiencies 7-8
Table 8-1: In Situ Mine Pools and Pit Lakes Case Study Sites 8-1
Table 8-2: Constituent Concentration Ranges Pre-, During and Post-Treatment - Island Copper Mine Pit
Lake 8-3
Table 8-3: Average Removal Efficiencies 8-4
Table 8-5: Constituent Concentration Ranges Pre- and Post-Treatment - Platoro Mine Pool 8-5
Table 8-6: Average Removal Efficiencies 8-7
xi
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Table 9-1: PRB Case Study Sites 9-1
Table 9-2: Maximum and Minimum Influent and Corresponding Effluent Concentrations - Success Mine
and Mill 9-3
Table 9-3: Maximum and Minimum Upgradient Concentrations and Corresponding Minimum
Concentrations Within the PRB and Corresponding Concentration Downgradient of the PRB - Nickel Rim
Mine 9-4
Table 9-4: Average Influent and Effluent Concentrations - Success Mine and Mill 9-5
Table 9-5: Average Upgradient and Within PRB Groundwater Concentrations - Nickel Rim Mine 9-5
Table 9-6: Removal Efficiencies - Success Mine and Mill 9-6
Table 10-1: Treatment Train Case Study Sites 10-2
Table 10-2: Maximum Influent and Corresponding Effluent Concentrations 10-9
Table 10-3: Minimum Influent and Corresponding Effluent Concentrations 10-9
Table 10-4: Maximum Average Influent Concentration Treated 10-11
Table 10-5: Minimum Average Influent Concentration Treated 10-13
Table 10-6: Maximum Average Effluent Concentration Attained 10-14
Table 10-7: Minimum Average Effluent Concentration Attained 10-15
Table 10-8: Maximum Removal Efficiencies 10-16
Table 10-9: Minimum Removal Efficiencies 10-17
Table 10-10: Influent Flow Rates 10-18
Table 10-11: Pre-Treatment Concentration Range and Post-Treatment Concentration in Stream Water
Downstream from Valzinco 10-20
Table 10-12: Maximum Pre-Treatment and Post-Treatment Concentrations for the Copper Basin Site .10-
20
Table 10-13: Maximum Average Pre-Treatment Concentration Treated 10-21
Table 10-14: Minimum Average Pre-Treatment Concentration Treated 10-22
Table 10-15: Maximum Average Post-Treatment Concentration Attained 10-22
Table 10-16: Minimum Average Post-Treatment Concentration Attained 10-23
Table 10-17: Maximum Average Removal Efficiencies 10-23
Table 10-18: Minimum Average Removal Efficiencies 10-24
Table 10-19: Average Influent and Effluent Concentrations - Monte Romero Mine 10-25
Table A-l: Maximum and Minimum Influent and Corresponding Effluent Concentrations - All Applicable
Case Studies A-l
Table A-2: Average Influent and Effluent Concentrations - All Applicable Case Studies A-10
Table A-3: Removal Efficiencies - All Applicable Sites A-15
xii
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Table B-l: Kristineberg Mine - Maximum and Minimum Leachate Concentrations from Capped and
Uncapped Tailings B-l
Table B-2: Dunka Mine-Average Pre-Capping and Post-Capping Concentrations B-2
Table C-l: Maximum and Minimum Influent and Corresponding Effluent Concentrations - All Applicable
Case Studies C-l
Table C-2: Average Influent and Effluent Concentrations - All Applicable Case Studies C-5
Table C-3: Average Mass Treated and Average Mass Removed per Year - Britannia Mine C-12
Table C-4: Removal Efficiencies - All Applicable Sites C-15
Table D-l: Average Influent and Effluent Concentrations - All Applicable Case Studies D-l
Table D-2: Removal Efficiencies - All Applicable Sites D-5
Table E-l: Maximum and Minimum Influent and Corresponding Effluent Concentrations - Calliope Mine
E-l
Table E-2: Maximum and Minimum Influent and Corresponding Effluent Concentrations - Force Crag. E-2
Table E-3: Influent and Effluent Concentrations - Golden Sunlight Mine E-3
Table E-4: Influent and Effluent Concentrations - Leviathan Mine E-3
Table E-5: Maximum and Minimum Influent and Corresponding Effluent Concentrations - Standard Mine
E-6
Table E-6: Maximum and Minimum Influent and Corresponding Effluent Concentrations - Surething
Mine E-7
Table E-7: Influent and Effluent Concentrations - Surething Mine E-8
Table E-8: Influent and Effluent Concentrations - Wheal Jane Mine E-8
Table E-9: Average Influent and Effluent Concentrations - Calliope Mine E-9
Table E-10: Average Influent and Effluent Concentrations - Leviathan Mine E-10
Table E-ll: Average Influent and Effluent Concentrations - Standard Mine E-12
Table E-12: Average Influent and Effluent Concentrations - Tar Creek E-12
Table E-13: Average Influent and Effluent Concentrations - Wheal Jane Mine E-13
Table E-14: Removal Efficiencies - Calliope Mine E-15
Table E-15: Removal Efficiencies - Golden Sunlight Mine E-15
Table E-16: Removal Efficiencies - Leviathan Mine E-16
Table E-17: Minimum, Maximum and Average Removal Efficiencies - Leviathan Mine E-18
Table E-18: Average Removal Efficiencies - Standard Mine E-19
Table E-19: Removal Efficiencies - Surething Mine E-20
Table E-20: Average Removal Efficiencies - Tar Creek E-20
Table E-21: Removal Efficiencies - Wheal Jane Mine E-21
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Table E-22: Median Removal Efficiencies - Wheal Jane Mine E-22
Table E-23: Pre- and Post-Reclamation Concentrations - Valzinco Mine E-23
Table E-24: Influent and Effluent Concentrations - Copper Basin Mining District E-23
Table E-25 Average Influent and Effluent Concentrations - Dunka Mine E-24
Table E-26: Average Removal Efficiencies - Dunka Mine E-28
Table E-27: Flow Rates - All Treatment Train Mine Sites E-31
Table E-28: Average Influent and Effluent Concentrations - Monte Romero Mine E-33
Table E-29: Average Removal Efficiencies - Monte Romero Mine E-34
xiv
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Acronyms and Abbreviations
ALD
Anoxic Limestone Drain
AML
Abandoned Mine Lands
ARD
Acid Rock Drainage
BCR
Biochemical Reactor
BOD
Biological Oxygen Demand
Clu-ln
Contaminated Site Clean-up Information
cm
Centimeter
DAS
Dispersed Alkaline Substrate
DL
Detection Limit
FRTR
Federal Remediation Technologies Roundtable
HDS
High-density Sludge
ITRC
Interstate Technology and Regulatory Council
kg
Kilogram
LD
Limestone-dosed
LF
Limestone-free
L/min
Liters per minute
m2
Square meter
mg/L
Milligrams per liter
MIW
Mining-influenced Water
NA
Not Applicable
ND
Not Detected
NFOL
Natural Iron (Fe)-Oxidizing Lagoon
NS
Not Stated
O&M
Operation and Maintenance
PRB
Permeable Reactive Barrier
RAPS
Reducing and Alkalinity Producing System
RL
Reporting Limit
SME
Silica Microencapsulation
SRB
Sulfate-reducing Bacteria
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SRBR Sulfate-reducing Bioreactor
TCLP Toxicity Characteristic Leaching Procedure
VFP Vertical Flow Pond
WTP Water Treatment Plant
Hg/I Micrograms per liter
pirn Micrometer
xvi
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Acknowledgments
Discussions with the EPA's National Mining Team prompted development of this report to add
to the knowledgebase of treatment technologies for cleanup at Superfund sites. The following
individuals are acknowledged for their technical reviews of this report: Kathleen Adam of the
U.S. Forest Service, Dr. Robert Ford of U.S. EPA Office of Research and Development, Ed
Hathaway of the U.S. EPA Region 1, and Dr. Robert Seal of the U.S. Geological Survey.
xvii
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Conversion Factors
Area
1
acre
=
4046.86
square meters (m2)
1
square meters (m2)
=
0.000247105
acre
Concentration
milligram per liter
1
(mg/l)
=
1000
micrograms per liter (ng/l)
micrograms per liter
1
(Mg/l)
=
0.001
milligrams per liter (mg/l)
Flow
cubic feet per second (ft3/s,
1
liter per minute (L/min)
=
0.000588578
or cfs)
cubic foot per second
1
(ft3/s, or cfs)
=
1,699
liters per minute (L/min)
cubic meters per second
1
liter per minute (L/min)
=
1.6667 x 10"5
(m3/s)
cubic meter per second
1
(m3/s)
=
60,000
liters per minute (L/min)
gallons per minute (gal/min
1
liter per minute (L/min)
=
0.264172
orgpm)
gallon per minute
1
(gal/min, orgpm)
=
3.78541
liters per minute (L/min)
cubic meter per second
gallons per minute
1
(m3/s)
=
15,850
(gal/min, orgpm)
gallons per minute
cubic meter per second
1
(gal/min, orgpm)
=
6.309xl0"5
(m3/s)
Length
1
foot (ft)
=
0.3048
meters (m)
1
meter (m)
=
3.28084
feet (ft)
Volume
1
cubic meter (m3)
=
264.171928
gallons (gal)
1
gallon (gal)
=
0.00378541
cubic meter (m3)
1
liter (L)
=
0.264172
gallon (gal)
1
gallon (gal)
=
3.78541
liter (L)
xviii
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1 Introduction
The U.S. Environmental Protection Agency conducts and supervises investigation and cleanup actions at
a variety of abandoned mine lands (AMLs). AMLs are those lands, waters and surrounding watersheds
where extraction, beneficiation, or processing of ores and minerals has occurred. EPA's AML Program
identifies ways to protect human health and the environment by pursuing opportunities to explore
innovative site cleanup and reuse opportunities at these sites. The research in this report was conducted
to identify information related to treatment technologies being used for mining site cleanup.
Case studies examining treatment technologies used for remediating mining-influenced water (MIW)
and mining wastes have been conducted at many hard rock mining sites and range in type from bench
studies to full-scale field studies. The research in this report was conducted to capture the capabilities,
efficiencies, technological and site-specific requirements, and lessons learned for technologies and
methods used. EPA's goals for the work presented in this document were to 1) determine if there are
any trends in treatments or methods used; 2) understand successes and failures of the technologies and
methods to evaluate whether there are gaps where future technologies could be developed or current
ones refined; and 3) provide information in one place to aid decision of whether a given technology or
method might be appropriate for use at a particular site, based on information obtained from the case
studies.
To work toward meeting these goals, EPA conducted a literature search in order to accumulate,
evaluate, and consolidate case studies that documented active or passive treatment systems or
methods being used (or previously used) at active and inactive hard rock mining sites for remediating
contaminants from various mining wastes and MIW. While not truly a treatment, literature that
documented source control through capping and covering of mining wastes was included. The media
types of interest included waste rock, tailings, soil, pit lakes, water from adits, underground workings,
leachate, groundwater, and surface water.
Technologies presented in this review are organized such that each chapter can be read alone. This
chapter lays out the goals and approach for developing this document and limitations in accomplishing
those goals.
1.1 Methodology
1.1.1 Scientific Literature Review Approach
The literature search focused on peer-reviewed case studies originating from governmental
organizations, non-governmental organizations, academia and contractors or consultants that contained
data from field studies assessing the effectiveness of various treatment technologies. Major
bibliographic databases were searched as part of this effort, including Science Direct, Web of Science,
EBSCOhost Science & Technology Collection, Environmental Sciences and Pollution Management,
Conference Papers Index, Pollution Abstracts, PubMed, and Google Scholar. Additional specific sources
searched included EPA's Contaminated Site Clean-Up Information (Clu-ln) webpage for mining site case
studies, EPA Mine Waste Technology Program references on source control or remediation methods,
the Interstate Technology and Regulatory Council (ITRC) webpage for mining waste treatment and
webpages for international and national mining associations and organizations, including: American
Society of Mining and Reclamation, International Mine Water Association, Society for Mining,
1-1
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Metallurgy, and Exploration, the International Network for Acid Prevention, and International
Conference on Acid Rock Drainage (ICARD) proceedings, each of whom peer-review conference papers
for publication in proceedings. The literature search was completed in 2017.
The literature search used the following tier 1 screening criteria:
• Field-scale (pilot or full) case studies documented in 1980 or later with the technology operating
and monitored for a minimum of six months for remediation purposes at active or inactive hard
rock mining sites.
• Field-scale studies that were intended to remove metals, metalloids and/or other inorganic
contaminants (e.g., sulfate) from media impacted by hard rock mining such as MIW, or
abatement of leachate or seepage through source control.
References meeting the first-level screening criteria were then grouped by case study site name and
further prioritized based on the following tier 2 criteria:
Required:
• Treatment technology or method clearly identified, as an independent system or part of a
treatment train.
• Geographical conditions/constraints (e.g., topography, climate, remoteness, footprint) provided.
• Scale of technology (pilot or full-scale application) indicated.
• Media treated clearly identified.
• Constituents treated identified.
• Process type (physical, chemical, biological or a combination of process types; active, passive or
semi-passive) discernable.
• Technology requirements clearly noted (e.g., power needs, temperature constraints, specific
microorganisms, etc.).
• If water, influent and effluent concentrations (averages over time or time-dependent data)
provided.
• If a solid medium, starting and ending concentrations provided in water source, such as
leachate.
• If a solid medium, area or mass of solid treated provided.
• Cleanup goals or other performance criteria provided.
• Statement or indication of whether the treatment method met or did not meet performance
goals.
Desired:
• Site name and location (unless confidential).
• If water, influent and effluent loads.
• If water, flows treated provided.
• Issues and lessons learned (technical, regulatory, logistical).
• Costs provided.
If the required tier 2 criteria were not present, EPA excluded the case study from quantitative data
evaluation; however, information from the study may have been used in qualitative discussions of the
1-2
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given technology. All primary sources of data used were EPA reports, peer-reviewed conference
proceedings, or journal articles.
Concerted effort was made to comprehensively search for a range of studies that encompass the
potential variability in mine waste types, contaminants present, and potential treatment technologies.
However, EPA acknowledges data gaps may exist and that this report may not include the universe of
data on this topic. Contaminants other than those presented in this report may be treatable by the
technologies evaluated, but were not presented in the studies examined.
EPA is aware of studies conducted at EPA sites that are not included in this report due to the lack of
data published for such studies. The Agency is working toward reporting these data in a form that can
be used for future analyses. EPA provides current information on contaminated mining site cleanup
treatment technologies at EPA's Cleanup Information Network (www.clu-in.org/mining).
1.1.2 Data Evaluation Procedures
Case studies meeting the second-tier criteria were organized by technology, media type, and primary
constituents assessed. For each technology, the following data were extracted for each case study that
documented successful treatment (i.e., performance goals were stated as having been attained or
constituent concentrations were decreased):
• Identity of each constituent (including pH) assessed and:
o Minimum and maximum pre-treatment concentration and corresponding post-
treatment concentration,
o Average pre-treatment and average post-treatment concentrations,
o Minimum, maximum, and average removal efficiency.
• Flows treated
• Costs
• Lessons learned
For MIW, concentrations correspond to the water being treated directly. For technologies treating solid
mining wastes, concentrations reported correspond to water leached from a waste pile before and after
treatment of the waste, or water from a source upgradient and downgradient (groundwater), or
upstream and downstream (stream water or seeps) of the waste pile being treated. Concentration and
removal efficiency data obtained in this step are presented in the technology-specific appendices,
whereas flows treated, costs, and lessons learned are presented within each technology chapter, where
available. Flows treated in case study references were converted to a consistent unit of measure (liters
per minute, L/min) across all technologies within this document.
Minimum and maximum pre-treatment and corresponding post-treatment data were obtained from
evaluation of tables, graphs, or narratives. In instances where only graphs were provided, data are noted
as being estimated from those graphs. Data were chosen from periods over which a case study reported
a technology as operating as intended, excluding start-up or equilibration periods. If operation versus
start-up or equilibration periods were not stated, data were chosen across the entire period presented.
Minimum pre-treatment concentrations chosen were the lowest concentrations reported that exceeded
a case study's reported detection limit (DL) for each constituent.
1-3
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Unless otherwise noted in tables, average pre-treatment and post-treatment concentrations were
reported by the authors of the case studies. In the absence of reported averages, where time-specific
data from multiple sampling events were available, EPA calculated average values from the reported
data. For calculations, one-half of the reported detection limit was used for samples reported as below
the detection limit; if no detection limit was provided, the average was not calculated. The average pH
presented in the tables represents the average of pH values, rather than an average pH calculated from
hydrogen ion activities. Unless otherwise noted, minimum, maximum, and average removal efficiencies
were reported by the authors of the case studies. Concentrations reported in case study references
were converted to a consistent unit of measure (milligrams per liter [mg/L]) across all technologies
within this document, where applicable.
For each technology, data in the appendices were examined across all case studies for each of the
constituents treated to choose the technology-based minimum and maximum pre-treatment
concentrations and their corresponding post-treatment concentrations, the minimum and maximum
average pre-treatment and post-treatment concentrations, and the minimum and maximum removal
efficiencies. These data are presented in tables and discussed in the capability section of each
technology chapter.
Many case studies presented treatment results from treatment trains, i.e., multiple technologies
conducted in series. Some of these studies provided data for each part of the treatment train, and these
data were included in individual technology discussions, as well as being discussed in the Treatment
Trains chapter (Section 10). Case studies that did not provide data for each unit in the treatment train
are discussed only in Section 10.
1.2 Limitations
When reviewing the capabilities of the technologies within this document, it is important to note that
average influent concentrations in tables do not correspond directly with the average effluent
concentrations. It also should be noted that, although the data from the case studies were examined in
aggregate within each technology, the case studies may not have been conducted in the same way, may
have had different detection limits for the same constituents examined, or may have had different
overall water chemistries, any of which may have influenced case study reported results in unknown
ways. For some technologies, the data reported in a case study may not be the most telling data for
evaluating successful treatment. For caps and covers, contaminant load reduction is often a pertinent
measure of performance yet the case studies examined did not present discussion in terms of loads
reduced.
For some technologies, this report only includes one or two case studies that met the required criteria;
therefore, the ability to determine general capability of those technologies is limited. In instances when
a given constituent may have been monitored in only one case study, generalized capability of the
technology with respect to that constituent is limited. Limitations for the technologies as presented in
each chapter were stated as such by the references cited and those limitations noted are not intended
to reflect all potential limitations of the given technology. Constraints noted for each technology are
also presented as stated in the references cited and are not intended to be inclusive of all the
constraints that may exist for a given technology.
1-4
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An additional challenge to comparing technologies across multiple case studies is that not all studies
report the same type of data, such as the type of water sample (total or dissolved) for which a
constituent concentration was reported. This work aimed to capture as many case studies as possible
that met the criteria indicated above and to compare as many constituents reported within each
technology as possible. Some studies reported total concentrations but may not have indicated the
method used to determine the total concentration. For example, it is unknown if studies conducted a
total digestion of the raw water sample (total-recoverable), of if they used a modified digestion method.
Some studies report dissolved concentrations, but without indication of the filtration size, and it is well-
known that colloidal particles will pass through a 0.45 micrometer (pim) filter and report as dissolved
concentrations. Further, some studies did not indicate whether constituent concentration results were
dissolved or total. Because case studies meeting this study's criteria were limited, it was necessary to
examine aggregated data in the appendices from different water sample types. Tables within each
chapter indicate total or dissolved concentrations for each constituent being discussed.
Each chapter includes a Lessons Learned section of technology constraints. These sections relied on
information presented in the available references. These constraints are not discussed at length in this
report but are intended to provide insights to the limitations of certain technologies. In addition,
although the treatment technologies presented in this report may have been tested or used at
additional sites, only those sites with information obtained through the literature search are included in
this report.
1-5
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2 Use of this Review
The main goal of this work was to provide a single place where a project manager or practitioner could
find information to determine if a given technology would be applicable to their specific needs, based on
information aggregated across as many case studies of each technology as possible. An additional goal
was to identify if there were any trends in treatments or methods used. Unfortunately, many case
studies reviewed did not provide the information needed to meet these goals. Additionally, many
studies had different site-specific characteristics and constituents to treat within a given technology.
Therefore, the aggregated information provided in this report is limited, limiting the ability to identify
trends in treatment methods to better capture the full utility of a technology. However, EPA believes the
information presented in this report will prove a valuable resource for site managers as a complement
to Reference Guide to Treatment Technologies for Mining-Influenced Water (U.S. EPA, 2014) which
provides information on how several of the treatment technologies evaluated in this review work.
EPA recognizes that information presented in journal articles and conference proceedings typically is
constrained by page limits. For journal articles, supplementary information may be provided, and
appendices provided for reports, but readers may not have the time to process those data themselves.
It is also recognized that cost information may not be presented in peer-reviewed case studies due to
competition amongst vendors or consultants, especially costs associated with labor. If literature
included costs of the technology itself (i.e., capital costs, plus materials over time) and then provided an
estimate of the numbers of hours necessary for monitoring, maintenance, or other activities, a
practitioner or project manager could compare suitable technologies based on capital costs and labor
hours. Presentation of costs and labor hours normalized to volume of water treated would be most
beneficial for comparison across technologies. Cost information in this document is presented as
reported in the case studies and has not been adjusted for inflation.
EPA may provide updated information as additional information or case studies become available.
2.1 References
U.S. Environmental Protection Agency (U.S. EPA). 2014. Reference Guide to Treatment Technologies for
Mining-Influenced Water. (EPA/542/R-14/001). 94 pp.
https://cluin.org/download/issues/mining/Reference Guide to Treatment Technologies for MlW.pdf
2-1
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Biochemical Reactors
3 Biochemical Reactors
Biochemical reactors (BCRs), sometimes called bioreactors, are engineered systems that use organic
materials and natural processes to decrease concentrations of a variety of metals, metalloids and
sulfate, and to increase pH in mining-influenced water (MIW). Treatment occurs through microbial,
chemical and physical processes, including reduction/oxidation, precipitation, adsorption and retention
within the substrate (Nordwick and Bless, 2008). Substrate materials used in these systems, such as
wood chips, straw, or biosolids, are often obtained locally. Organic waste materials such as biosolids or
manure are put to new use when employed as part of the treatment system within a BCR (Gusek, 2002).
BCR design varies based on site-specific characteristics such as water chemistry (including pH, metals
type and concentration), influent water flow rates, climate, temperature, land and power source
availability, and treatment goals (Doshi, 2006; Butler et al., 2011). BCRs using solid substrates are
considered passive systems, meaning that they require minimal human interaction to operate once the
microbial community is established; they are also referred to as semi-passive systems since it is required
that they be maintained overtime. BCRs using liquid substrates can be considered active systems
because they require more frequent human interaction to replace the carbon source and may also have
greater power needs that require more frequent maintenance visits. Passive BCR systems rely on gravity
feeds, which require minimal maintenance, whereas a BCR requiring some power for conveying water
may be considered a semi-passive system that requires occasional human interaction. BCRs can be
placed inside mine shafts or other mining site features (in situ). They can also be in-ground systems or
above-ground containerized systems. A polishing step generally follows BCR treatment to remove
constituents introduced by microbial activity and settle out any solids released during the process.
BCRs can be aerobic (oxic) or anaerobic (anoxic). Anaerobic BCRs are more commonly used to treat
MIW. Anaerobic BCRs are also sometimes called sulfate-reducing bioreactors (SRBRs), compost
bioreactors, or vertical flow ponds (VFPs), although the primary goal of a VFP is to add alkalinity and
create reducing conditions rather than facilitating microbially-mediated precipitation (Hedin et al.,
2013). For this review, engineered bioreactors using anaerobic biochemical processes are called
"anaerobic BCRs" and engineered bioreactors using aerobic biochemical processes are called "aerobic
BCRs."
Anaerobic BCRs harness the microbial ability of dissimilatory sulfate-reducing bacteria (SRB) to reduce
dissolved sulfate in MIW to hydrogen sulfide (Equation 1, using acetic acid as an example carbon
source). Dissolved hydrogen sulfide dissociates into hydrogen and bisulfide ions (Equation 2), and the
bisulfide then reacts with dissolved metal contaminants in MIW to precipitate metal sulfides, as shown
in Equation 3, which are retained within the BCR substrate.
CH3COOH + SO|~ o 2HCO3 + H2S Equation 1
H2S(aq) o HS~ + H+,pka = 7 Equation 2
HS~ + Me2+ o MeS + H+, where Me2+ = any divalent metal Equation 3
The metabolic process also produces bicarbonate (Equation 1) that can neutralize acidity (Bless et al.,
2008; Nordwick and Bless, 2008). SRB need an anoxic, reducing environment and an electron donor
(carbon substrate) to function (Doshi, 2006).
3-1
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Biochemical Reactors
Aerobic BCRs often rely on precipitation of metals as oxides and hydroxides under aerobic conditions to
decrease metals concentrations (Gusek, 2002); the precipitates also sequester trace elements, such as
cadmium, copper, and zinc through sorption. In one case study in this chapter, manganese-oxidizing
bacteria were used to induce manganese oxidation (Nordwick and Bless, 2008). BCRs are often used as
part of a treatment train (see Section 10).
3.1 Case Studies Evaluated
This chapter provides an evaluation of case studies in which a BCR was the primary component of MIW
treatment. The case studies were selected based on the criteria presented in Section 1.1.1. The case
studies examined included aerobic and anaerobic BCRs in pilot-scale and full-scale installations at mine
sites across the United States, Canada and the United Kingdom. Table 3-1 summarizes site names and
locations, BCR design information, and references for each of the case studies. The chapter presents
technology-wide considerations for constraints, treatability of contaminants, capability, technological
and site-specific requirements and lessons learned for BCR treatment from evaluation of case study
results.
Table 3-1: Bioreactor Case Study Sites
Site Name
BCR Type
System
Study Type
Reference
Reference
and
Description
Type
Location
Calliope
Anaerobic,
Three horizontal
Pilot scale
Wilmoth,
Report
Mine
solid
flow units in
(technology
2002*
Butte,
substrate
parallel: two below
demonstration)
Bless et al.,
Journal paper
Montana
ground with one
2008
having
Nordwick et
Conference
pretreatment and
al., 2006
paper
one aboveground
with pretreatment;
each unit
contained organic
matter (cow
manure and straw)
and cobbles; pre-
treatment units
contained
additional organic
matter and
limestone.
3-2
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Biochemical Reactors
Table 3-1: Bioreactor Case Study Sites
Site Name
BCR Type
System
Study Type
Reference
Reference
and
Description
Type
Location
Confidential
Anaerobic,
BCR followed by
Pilot scale
Blumenstein
Conference
Mine,
solid
an aerobic
(technology
and Gusek,
paper
Montana
substrate
polishing cell (a
demonstration)
2009*
series of vegetated
ponds); BCR
substrate
consisted of 46
percent wood
chips, 10 percent
hay, 30 percent
limestone, 10
percent animal
manure and 4
percent crushed
basalt.
Cwm
Anaerobic,
Vertical-flow
Pilot scale
Jarvis et al.,
Report
Rheidol
solid
bioreactor
2014*
Mine
substrate
contained shells,
Wales,
wood chips,
United
compost and
Kingdom
anaerobic digested
sludge.
Force Crag
Anaerobic,
Parallel vertical-
Full scale
Jarvis et al.,
Conference
Cumbria,
solid
flow ponds
2015*
paper
United
substrate
contained
Kingdom
compost,
woodchips and
dried activated
sewage sludge,
followed by an
aerobic wetland.
Keno Hill
Anaerobic,
Liquid BCR filled
Pilot scale
Harrington
Conference
Yukon,
liquid
with adit water
et al., 2015*
paper
Canada
substrate
supplemented
with sucrose,
methanol and
dried milk solids;
continuous
methanol once
established.
Leviathan
System consisted
Full scale
Doshi, 2006
Report
Mine
of a pretreatment
3-3
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Biochemical Reactors
Table 3-1: Bioreactor Case Study Sites
Site Name
BCR Type
System
Study Type
Reference
Reference
and
Description
Type
Location
Alpine
Anaerobic,
pond (using 25
U.S. EPA,
Report
County,
liquid
percent sodium
2006a*
California
substrate
hydroxide and
ethanol), two BCRs
in series, two
continuous flow-
settling ponds, and
an aeration
channel; BCRs
were lined with
high-density
polyethylene, river
rock and manure.
Lilly Orphan
Anaerobic,
In-situ BCR built
Pilot scale
Bless et al.,
Journal paper
Boy Mine
solid
within the mine
(technology
2008*
Elliston,
substrate
shaft and
demonstration)
Montana
containing 70
percent cow
Doshi, 2006
Report
manure, 20
percent
decomposed wood
chips and 10
percent alfalfa
straw.
Nenthead
Anaerobic,
Vertical flow
Pilot scale
Jarvis et al.,
Report
Cumbria,
solid
bioreactor
2014*
United
substrate
containing
Kingdom
compost, wood
chips and activated
digested sludge.
Standard
Anaerobic,
System comprised
Pilot scale
Gallagher et
Conference
Mine
solid
a BCR followed by
al., 2012*
paper
Crested
substrate
aerobic polishing
Reisman et
Conference
Butte,
cells; BCR
al., 2009*
paper
Colorado
contained hay,
wood chips,
limestone and cow
manure.
Butler et al.,
2011
Journal paper
3-4
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Biochemical Reactors
Table 3-1: Bioreactor Case Study Sites
Site Name
BCR Type
System
Study Type
Reference
Reference
and
Description
Type
Location
Surething
Anaerobic
System comprised
Pilot scale
Nordwick
Report
Mine
and aerobic,
an anaerobic BCR
(technology
and Bless,
Helena,
solid
followed by an
demonstration)
2008*
Montana
substrates
anoxic limestone
drain, followed by
another anaerobic
BCR, followed by
an aerobic BCR
containing
manganese-
oxidizing bacteria.
Notes:
*Primary source(s) of data for evaluation in this chapter
3.2 Constraints
Constraints associated with BCRs include the need for space and suitable topography to accommodate
system components, operating issues due to clogging of pipes or substrates, the unknown longevity of
substrates, and variable seasonal flow (U.S. EPA, 2006a; Doshi, 2006; Harrington et al, 2015). Lack of an
accessible source of electricity (if pumping is required), limited site access during winter months and
cold temperatures may also be constraints (Reisman et al., 2009; U.S. EPA, 2006a). For example, at the
Leviathan Mine in California, only snowmobiles could reach the site's remote location during winter
months, requiring detailed planning to ensure the BCR's continued operation (U.S. EPA, 2006a). Another
example is the Standard Mine site in Colorado, which is only accessible via snowshoes and skis during
winter months (Reisman et al., 2009).
Liquid substrate BCRs face an additional constraint - the need to transport and maintain an adequate
supply of liquid reagents (e.g., ethanol or molasses), fuels (to maintain generators) and other supplies to
ensure consistent system operations, even when site access may be limited. Liquid substrates are often
consumed much faster by SRB than are solid substrates (Gusek, 2002). Personnel may also need to be
on site more often to deliver supplies and conduct operation and maintenance activities (Doshi, 2006).
Challenges or concerns may arise from siting BCRs at locations near populated areas, such as
stakeholder concerns about a rotten egg odor caused by the BCR's production of hydrogen sulfide gas,
additional permitting requirements, and worries about damages to the system or injury to individuals
due to trespassing (Interstate Technology & Regulatory Council [ITRC], 2013). Additionally, at the end of
a BCR's lifetime, accumulated precipitates and residual media may be determined to require disposal as
a hazardous waste, depending on the results of the toxicity characteristic leaching procedure (TCLP)
(ITRC, 2013).
In most cases, careful planning and coordination with stakeholders during BCR design can address their
concerns. To some extent, BCR design and operation can also be modified over time as technical issues
3-5
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Biochemical Reactors
affecting operation or efficiency arise. Section 3.8 of this chapter discusses lessons learned from the
case studies examined.
3.3 Treatable Contaminants
BCRs can treat a variety of metals, metalloids, non-metals and increase pH in MIW.
3.3.1 Anaerobic, Solid Substrate BCRs
Although many anaerobic BCR case studies evaluated targeted treatment of a small number of site-
specific chemicals of concern, some provided results of additional metals, metalloids or non-metals
present in the MIW that also were decreased in concentration. When examined in aggregate, the
studies show the following metals, metalloids and non-metals are treatable using anaerobic BCRs:
aluminum, arsenic, cadmium, copper, iron, lead, manganese, nitrate, selenium, sulfate, thallium and
zinc. Although iron and manganese concentrations can be decreased in anaerobic BCRs, removal may be
less efficient than with other elements, and inconsistent (Nordwick and Bless, 2008; Reisman et al.,
2009). An increase in pH is also attainable by anaerobic BCRs. Other elements (e.g., cobalt, mercury,
nickel, tin) also may be treatable by anaerobic, solid substrate BCRs, but were not presented in the
studies examined.
3.3.2 Anaerobic, Liquid BCRs
Based on two case studies meeting the criteria included in this report (U.S. EPA, 2006a; Harrington et al.,
2015), liquid BCRs can treat aluminum, antimony, arsenic, cadmium, chromium, copper, iron, lead,
nickel, sulfate, sulfide, selenium and zinc.
3.3.3 Aerobic, Solid Substrate BCRs
An aerobic BCR can treat manganese and increase pH, based on a single case study (Nordwick and Bless,
2008) included that met the criteria for this work.
3.4 Capability-Anaerobic, Solid Substrate
3.4.1 Ranges of Applicability
Concentrations of metals tend to be inversely related to the pH, with higher concentrations associated
with a lower pH and lower concentrations associated with a higher pH. Tables 3-2 and 3-3 show the
ranges of applicability for each constituent - the maximum influent concentration (and the lowest
influent pH) and the corresponding effluent concentration, and the minimum influent concentration
(and the highest influent pH) and the corresponding effluent concentration, respectively. The ranges
were determined by comparisons of data in Table A-l, Appendix A, developed as discussed in Section
1.1.2. For studies having multiple BCRs in series, results from only the first BCR were compared because
concentrations of multiple constituents often were below reported detection limits in influent to
subsequent BCRs, and therefore are not representative of treatment capability. Additionally, case
studies having pretreatment without reporting the concentrations following pretreatment (i.e., influent
concentrations to the BCR step; examples are Golden Sunlight in Nordwick and Bless, 2008 and
Bioreactors II and IV at Calliope Mine in Wilmoth, 2002) were excluded from data comparison to allow
evaluation of strictly the capability of the BCR technology, but are discussed in the Treatment Trains
chapter (Section 10).
3-6
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Biochemical Reactors
Table 3-2: Maximum Influent and Corresponding Effluent Concentrations
Constituent
Maximum
Influent
Concentration
Corresponding
Effluent
Concentration
Mine
Source
Concentrations reported in mg/L; pH reported in standard unit
Aluminum3-b
14.1
0.0453
Calliope (BCR III)
Wilmoth, 2002
Arsenicc
1.25
0.01
Surething (Reactor 1)
Nordwick and Bless, 2008
Cadmiumc
0.385
0.005
Surething (Reactor 1)
Nordwick and Bless, 2008
Copperc
4.25
<0.003
Surething (Reactor 1)
Nordwick and Bless, 2008
Iron3
89.8
0.7
Standard
Gallagher et al., 2012
Lead3d
6
<0.008
Standard
Reisman et al., 2009
Manganese0
65
20
Surething (Reactor 1)
Nordwick and Bless, 2008
Nitrateef
7.9
ND
Confidential
Blumenstein and Gusek, 2009
Seleniume,f
0.025
ND
Confidential
Blumenstein and Gusek, 2009
Sulfate0
900
450
Surething (Reactor 1)
Nordwick and Bless, 2008
Thalliumef
1.6
<0.001
Confidential
Blumenstein and Gusek, 2009
Zincc
39
<0.007
Surething (Reactor 1)
Nordwick and Bless, 2008
PH
3.29
7.56
Calliope (BCR III)
Wilmoth, 2002
Notes:
ND = Assumed not detected based on figures referenced in Appendix A, Table A-l; detection limits
unknown
a = Total
b = Aluminum was reported only for the Calliope Mine site
c = Dissolved
d = Lead was reported only for the Standard Mine site
e = Total or dissolved not statec
f = Nitrate, selenium and thallium were reported only for the Confidential Mine site
Table 3-3: Minimum Influent and Corresponding Effluent Concentrations
Constituent
Minimum
Influent
Concentration
Corresponding
Effluent
Concentration
Mine
Source
Concentrations reported in mg/L; pH reported in standard units
Aluminum3-b
0.011
0.0094
Calliope (BCR III)
Wilmoth, 2002
Arsenicc
0.0051
<0.005
Calliope (BCR III)
Wilmoth, 2002
Cadmiumc
0.0051
0.0056
Calliope (BCR III)
Wilmoth, 2002
Copperc
0.003
0.0013
Standard
Gallagher et al., 2012
Iron3
0.008
0.031
Calliope (BCR III)
Wilmoth, 2002
Leadcd
0.011
0.0009
Standard
Gallagher et al., 2012
Manganese3
0.69
0.076
Calliope (BCR III)
Wilmoth, 2002
Nitrateef
2.9
0.1
Confidential
Blumenstein and Gusek, 2009
Seleniume,f
0.01
ND
Confidential
Blumenstein and Gusek, 2009
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Biochemical Reactors
Table 3-3: Minimum Influent and Corresponding Effluent Concentrations
Constituent
Minimum
Corresponding
Mine
Source
Influent
Effluent
Concentration
Concentration
Concentrations reported in mg/L; pH reported in standard units
Sulfatec,g
40
106
Surething
Nordwick and Bless, 2008
(Reactor 1)
Thallium6
0.25
<0.001
Confidential
Blumenstein and Gusek, 2009
Zincc
1.7
0.2
Nenthead
Jarvis et al., 2014
PH
8.0
7.2
Confidential
Blumenstein and Gusek, 2009
Notes:
ND = Assumed not detected based on figures referenced in Appendix A, Table A-l; detection limits
unknown
a = Total
b = Aluminum was reported only for the Calliope site
c = Dissolved
d= Lead was reported only for the Standard Mine site
e = Total or dissolved not specified
f = Nitrate, selenium and thallium were reported only for the Confidential Mine site
g = Force Crag had the lowest influent sulfate concentration (19.3 mg/L), but did not provide a
corresponding effluent concentration
Table 3-2 shows that based on the studies examined, anaerobic BCRs can decrease concentrations of
aluminum, arsenic, cadmium, copper, iron, lead, thallium and zinc by at least two orders of magnitude
when starting with concentrations exceeding 1 mg/L (> 0.300 mg/L for cadmium). Treatment of zinc
appears most effective, with the greatest decrease of four orders of magnitude as compared to the
other constituents. Aluminum, copper and lead also are effectively treated with decreases in
concentrations of three orders of magnitude. Treatment of nitrate and selenium is also effective, with
concentrations decreasing to the assumed detection limit when starting with concentrations less than
10 mg/L nitrate and less than 0.03 mg/L selenium at the single site where monitored. Manganese and
sulfate are less effectively treated at the maximum influent concentrations, with 69 percent and 50
percent decreases between the maximum influent and corresponding effluent concentrations,
respectively. The pH was also increased when influent pH was below 4.
Table 3-3 shows that based on the studies examined, anaerobic BCRs are also able to decrease
concentrations of aluminum, arsenic, copper, lead, manganese, nitrate, selenium, thallium and zinc
when influent concentrations are low (< 1 mg/L; 1.7 mg/L for zinc; 2.9 mg/L for nitrate). Thallium
concentration had the greatest decrease of two orders of magnitude and was decreased to below the
detection limit for the single site where monitored. Influent concentrations of arsenic, cadmium and
copper were near the detection limit values, so removal (or lack thereof, in the case of cadmium)
observed may be due simply to inherent instrumental errors associated with measurements of values
close to detection capabilities. Removal was poor for iron and sulfate at minimum influent
concentrations, with each having effluent concentrations greater than influent concentrations and this
may be an artifact of sampling not corresponding to BCR retention times for systems having a wide
range in influent concentrations (see Appendix A, Table A-l for maximum and minimums for each site).
3-8
-------
Biochemical Reactors
3.4.2 Average Influent and Effluent Concentrations
Tables 3-4 and 3-5 list the highest and lowest average influent concentrations treated for each
constituent, respectively. Tables 3-6 and 3-7 list the highest and lowest average effluent concentrations
attained for each constituent, respectively. Values in these tables were determined by looking across
data in Appendix A, Table A-2. As discussed in the Introduction, Section 1.1.2, average maximum or
minimum influent concentrations do not correspond directly with the average effluent concentrations in
Tables 3-4 or 3-5, respectively, and attainment of a given constituent average maximum or minimum
effluent concentration may not require treating the same average influent concentration shown in the
Tables 3-6 or 3-7, respectively.
Table 3-4: Maximum Average Influent Concentration Treated
Constituent
Maximum
Average
Influent
Concentration
Average Effluent
Concentration
Mine
Source
Concentrations reported in mg/L and as dissolved, except nitrate, selenium and thallium (total or
dissolved not stated); pH reported in standard units
Aluminum
9.7
<0.02
Lilly/Orphan Boya
Bless et al., 2008
Arsenic
1.07b
0.075
Lilly/Orphan Boya
Bless et al., 2008
Cadmium
0.33
<0.005
Lilly/Orphan Boya
Bless et al., 2008
Copper
0.4078
0.0546
Calliope
Wilmoth, 2002
Iron
27.7
11.25
Lilly/Orphan Boya
Bless et al., 2008
Leadb
0.54
0.01
Standard
Reisman et al., 2009
Manganese
10.99
10.53
Standard
Reisman et al., 2009
Nitratec
5.1
0.08
Confidential
Blumenstein and
Gusek, 2009
Seleniumc
0.013
0.001
Confidential
Blumenstein and
Gusek, 2009
Sulfate
281
119
Standard
Gallagher et al., 2012
Thallium'
1.25
0.007
Confidential
Blumenstein and
Gusek, 2009
Zinc
26.46
0.55
Standard
Reisman et al., 2009
PH
3.0
7.2
Lilly/Orphan Boy
Bless et al., 2008
Notes:
a = Average influent concentration provided was from 1993-1994; average effluent concentration
calculated by EPA from data provided in the reference for two sampling dates in 2001
b = Lead was monitored only at the Standard Mine
c = Nitrate, selenium and thallium were monitored only at the Confidential Mine site
3-9
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Biochemical Reactors
Table 3-5: Minimum Average Influent Concentration Treated
Constituent
Minimum
Average
Influent
Concentration
Average Effluent
Concentration
Mine
Source
Concentrations reported in mg/L i
dissolved not stated); pH reportec
and as dissolved, except nitrate, selenium and thallium (total or
in standard units
Aluminum
1.2229
0.0616
Calliope
Wilmoth, 2002
Arsenic
1.07a
0.075a
Lilly/Orphan Boyb
Bless et al., 2008
Cadmium
0.0112
<0.005
Calliope
Wilmoth, 2002
Copper
0.26
<0.0038
Standard
Reisman et al., 2009
Iron
0.4556
0.4143
Calliope
Wilmoth, 2002
Lead
0.54
0.01
Standard
Reisman et al., 2009
Manganese
1.4581
1.0073
Calliope
Wilmoth, 2002
Nitratec
5.1
0.08
Confidential
Blumenstein and
Gusek, 2009
Seleniumc
0.013
0.001
Confidential
Blumenstein and
Gusek, 2009
Sulfate
0.1029
0.1039
Calliope
Wilmoth, 2002
Thalliumc
1.25
0.007
Confidential
Blumenstein and
Gusek, 2009
Zinc
2.8406
0.7944
Calliope
Wilmoth, 2002
PH
6.05
7.16
Calliope
Wilmoth, 2002
Notes:
a = Average influent arsenic concentration was reported above the detection limit only in the
Lilly/Orphan Boy study
b = Average influent concentration provided was from 1993-1994; average effluent concentration
calculated by EPA from data provided in the reference for two sampling dates in 2001
c = Nitrate, selenium and thallium were monitored only at the Confidential Mine site
Table 3-6: Maximum Average Effluent Concentration Attained
Constituent
Maximum
Average
Effluent
Concentration
Average Influent
Concentration
Mine
Source
Concentrations reported in mg/L and as dissolved, except nitrate, selenium and thallium (total or
dissolved not stated; pH reported in standard units
Aluminum
0.0616
1.2229
Calliope
Wilmoth, 2002
Arsenic
0.075
1.07a
Lilly/Orphan Boyb
Bless et al., 2008
Cadmium
<0.005
0.0112
Calliope
Wilmoth, 2002
Copper
0.0546
0.4078
Calliope
Wilmoth, 2002
Iron
11.25
27.7
Lilly/Orphan Boyb
Bless et al., 2008
3-10
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Biochemical Reactors
Table 3-6: Maximum Average Effluent Concentration Attained
Constituent
Maximum
Average
Effluent
Concentration
Average Influent
Concentration
Mine
Source
Lead
0.01
0.54
Standard
Reisman et al., 2009
Manganese
10.53
10.99
Standard
Reisman et al., 2009
Nitratec
0.08
5.1
Confidential
Blumenstein and
Gusek, 2009
Seleniumc
0.001
0.013
Confidential
Blumenstein and
Gusek, 2009
Sulfate
136.5
277
Lilly/Orphan Boyb
Bless et al., 2008
Thallium'
0.007
1.25
Confidential
Blumenstein and
Gusek, 2009
Zinc
0.7944
2.8406
Calliope
Wilmoth, 2002
pHd
7.16
6.05
Calliope
Wilmoth, 2002
Notes:
a = Average influent arsenic concentration was reported above the detection limit only in the
Lilly/Orphan Boy study
b = Average influent concentration provided was from 1993-1994; average effluent concentration
calculated by EPA from data provided in the reference for two sampling dates in 2001
c = Nitrate, selenium and thallium were monitored only at the Confidential Mine site
d = Lower average effluent pH correlates with higher average effluent constituent concentrations
Table 3-7: Minimum Average Effluent Concentration Attained
Constituent
Minimum
Average
Effluent
Concentration
Average Influent
Concentration
Mine
Source
Concentrations reported as dissolved in mg/L; pH reported in standard units
Aluminum
<0.02
9.7
Lilly/Orphan Boya
Bless et al., 2008
Arsenic
0.075
1.07b
Lilly/Orphan Boya
Bless et al., 2008
Cadmium
0.00019
0.095c
Standard
Gallagher et al., 2012
Copper
0.0014
o
o
Standard
Gallagher et al., 2012
Iron
0.4143
0.4556
Calliope
Wilmoth, 2002
Lead
0.00215
0.134c
Standard
Gallagher et al., 2012
Manganese
1.0073
1.4581
Calliope
Wilmoth, 2002
Nitrated
0.08
5.1
Confidential
Blumenstein and
Gusek, 2009
Seleniumd
0.001
0.013
Confidential
Blumenstein and
Gusek, 2009
Sulfate
0.1039
0.1029
Calliope
Wilmoth, 2002
3-11
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Biochemical Reactors
Table 3-7: Minimum Average Effluent Concentration Attained
Constituent
Minimum
Average
Effluent
Concentration
Average Influent
Concentration
Mine
Source
Thalliumd
0.007
1.25
Confidential
Blumenstein and
Gusek, 2009
Zinc
0.032
26.1
Lilly/Orphan Boya
Bless et al., 2008
PH
7.2
3.0
Lilly/Orphan Boyb
Bless et al, 2008
Notes:
a = Average influent concentration provided was from 1993-1994; average effluent concentration
calculated by EPA from data provided in the reference for two sampling dates in 2001
b = Average influent arsenic concentration was reported above the detection limit only in the
Lilly/Orphan Boy study
c = Calculated by EPA from average effluent concentration and percent removal provided: 100*
(avg in - avg out)/avg in = % removal
d = Nitrate, selenium and thallium were monitored only at the Confidential Mine site
Although they are not directly comparable, both the highest and lowest average influent concentrations
are able to be treated to some degree in anaerobic BCRs, as shown in Tables 3-4 and 3-5 with average
effluent concentrations of aluminum, arsenic, cadmium, copper, iron, lead, nitrate, selenium, thallium
and zinc being lower than average influent concentrations. Comparison of Tables 3-4 and 3-5 with Table
3-6 suggests that, on average, there is minimal or no treatment of manganese with average influent and
average effluent concentrations being similar. Average iron and sulfate concentrations are decreased;
however, the magnitude of decrease is less than that for other analytes and the decrease is less for
lower average influent concentrations. Metal sulfides having higher solubility constants (lower pKs) form
more slowly and are dissolved more quickly than metal sulfides having lower solubility constants (higher
pKs); solubility constants also are dependent on temperature and pH. The pKs values for manganese and
iron sulfide precipitates at 25 °C are 17.2, 9.6, and 12.6 for FeS, MnS (pink) and MnS (green),
respectively; for comparison, the pKs values for CdS, CuS, and ZnS (as sphalerite) are 26.1, 35.2, and
23.0, respectively (Blais et al., 2008). Precipitation also is competitive and higher concentrations of more
stable sulfides will outcompete those that are less stable; therefore, lesser decreases, or no decreases in
concentrations of iron and manganese, on average, are therefore not surprising. Table 3-7 shows that,
on average, anaerobic BCRs are capable of decreasing aluminum concentrations to levels below
detection limits. Table 3-6 also shows that, on average, anaerobic BCRs are capable of decreasing
cadmium concentrations to below detection limits, but comparison with cadmium in Table 3-7 shows
that detection limits vary between studies.
3.4.3 Removal Efficiency
The maximum and minimum removal efficiencies in Tables 3-8 and 3-9, respectively, were determined
by comparing values in Appendix A, Table A-3. Each constituent's maximum removal efficiency in Table
3-8 is the higher percentage of either the average or the maximum removal efficiency in Table A-3, and
each minimum removal efficiency in Table 3-9 is the lower percentage of either the average or the
minimum removal efficiency in Table A-3. Comparison of minimum and maximum removal efficiencies
3-12
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Biochemical Reactors
also was determined by sample type - total or dissolved. Several case studies had multiple treatment
components and reported removal efficiencies for the overall treatment train and those are not
included in this section or in Table A-3 because they do not reflect removal efficiencies specific to the
BCRs.
Table 3-8: Maximum Removal Efficiencies
Constituent
Maximum Removal
Efficiency
Mine
Source
Aluminum3
99.73%
Calliope - BCR lllbc
Wilmoth, 2002
Arsenic3
86.89%
Calliope - BCR lllbc
Wilmoth, 2002
Cadmium
99.80%
Standardd
Gallagher et al., 2012
Copper
99.37%
Calliope - BCR lllbc
Wilmoth, 2002
Iron
97.94%
Calliope - BCR lllbc
Wilmoth, 2002
Lead®
98.40%
Standardd
Gallagher et al., 2012
Manganese3
98.05%
Calliope - BCR lllbc
Wilmoth, 2002
Nitratef
>99%
Confidential8
Blumenstein and Gusek,
2009
Seleniumf
>99%
Confidential8
Blumenstein and Gusek,
2009
Sulfate
57.20%
Standardd
Gallagher et al., 2012
Thalliumf
99.97%
Confidential
Blumenstein and Gusek,
2009
Zinc
100.00%
Cwm Rheidold
Jarvis et al., 2014
Notes:
a = Only monitored at Calliope
b = Values calculated by EPA from data provided in Table 5-6
c = Total
d = Dissolved
e = Only monitored at Standard Mine
f = Only monitored at the Confidential Mine site; total or dissolved not stated
g = Assumed to be greater than 99 percent based on corresponding effluent data assumed to
be at or below detection limits based on figures referenced in Appendix A, Table A-3
h = Value calculated by EPA from data in Figure 7 of Blumenstein and Gusek, 2009; for non-
detect results, EPA used Vz the detection limit for calculations
Table 3-9: Minimum Removal Efficiencies
Constituent
Minimum Removal
Efficiency
Mine
Source
Aluminum3
-650.00%
Calliope - BCR lllbc
Wilmoth, 2002
Arsenic3
-95.38%
Calliope - BCR lllbc
Wilmoth, 2002
Cadmium
-9.80%
Calliope - BCR lllbc
Wilmoth, 2002
Copper
-189.59%
Calliope - BCR lllbc
Wilmoth, 2002
Iron
-14275.00%
Calliope - BCR lllbc
Wilmoth, 2002
Leadd
98.10%
Standard®
Reisman et al., 2009
3-13
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Biochemical Reactors
Table 3-9: Minimum Removal Efficiencies
Constituent
Minimum Removal
Efficiency
Mine
Source
Manganese3
-108.22%
Calliope - BCR lllbc
Wilmoth, 2002
Nitratef
96.55%
Confidential®8
Blumenstein and Gusek,
2009
Seleniumf
>99%
Confidentiale,h
Blumenstein and Gusek,
2009
Sulfate
-68.63%
Calliope - BCR lllbc
Wilmoth, 2002
Thalliumf
99.8%
Confidential®8
Blumenstein and Gusek,
2009
Zinc
-11.97%
Calliope - BCR lllbc
Wilmoth, 2002
Notes:
a = Only reported for Calliope
b = Values calculated by EPA from data provided in Table 5-6
c = Total
d = Only monitored at Standard Mine
e = Total or dissolved not stated in reference
f = Only monitored at the Confidential Mine site
g = Values calculated by EPA from data provided in figures referenced in Appendix A, Table A-3
h = Assumed to be greater than 99 percent based on corresponding effluent data assumed to
be at or below detection limits based on figures referenced in Appendix A, Table A-3
As shown by comparing data in both tables, removal efficiencies from anaerobic BCR treatment in the
studies examined span a wide range for most constituents. When comparing constituents where this
information was available from more than one case study, the widest range (~126 percent) occurs for
sulfate, while the smallest range (~110 percent) occurs for cadmium. Selenium and thallium had greater
than 99 percent removal efficiencies at the single case study included in this report that reported results
for these constituents.
The negative removal efficiencies for multiple constituents in Table 3-9 were from a single case study in
which EPA calculated the sampling date specific removal efficiencies from the corresponding influent
and effluent data provided in the study (Wilmoth, 2002). Some sampling dates had concentrations of
aluminum, arsenic, cadmium, copper, iron, manganese, sulfate and zinc in the effluent samples that
were higher than the corresponding influent samples used for calculating removal efficiencies. Wilmoth
(2002) hypothesizes that higher concentrations of constituents in the effluent samples may have
occurred for a variety of constituent specific reasons.
3.4.4 Flow Rates
Table 3-10 presents flow rates for anaerobic BCRs using solid substrates.
Table 3-10: Flow Rate - Anaerobic, Solid Substrate
Operational Flow Rate
Mine
Source
All rates are in liters per minute (L/min)
3-14
-------
Biochemical Reactors
Table 3-10: Flow Rate - Anaerobic, Solid Substrate
Operational Flow Rate
Mine
Source
3.8a
Calliope
Wilmoth, 2002
3.8- 19.3b
Confidential
Blumenstein and Gusek,
2009 (Figure 6, text)
1.9-4.5
Cwm Rheidol
Jarvis et al., 2014
1.1
Nenthead
Jarvis et al., 2014
7.6
Lilly Orphan Boy
Bless et al., 2008
3.8
Standard
Gallagher et al., 2012
< 7.6C
Surething
Nordwick and Bless, 2008
Notes:
a = Operated at 7.6 L/min for four months
b = Typically operated at or below design flow rate of 18.9 L/min
c = Operational flow stated as below the design flow of 7.6 L/min
As shown in Table 3-10, anaerobic, single-unit solid substrate BCRs can treat flows of 3.8-19.3 L/min in
the studies examined. Anaerobic BCRs (or SRBRs) commonly are included as part of a treatment train,
with higher influent flows able to be treated over the entire system; for example, see discussions of case
studies in Chapter 5 of Doshi (2006). One evaluated case study reported a higher design flow rate of 180
L/min for a single unit solid substrate BCR (Jarvis et al., 2015).
Additionally, all the studies providing operational flow rate information were pilot-scale studies (some
were demonstration type) and may not be representative of actual treatable flow capability of full-scale
BCRs.
3.5 Capability-Anaerobic, Liquid Substrate
Only two case studies using liquid substrates for their anaerobic BCRs met the screening criteria for
inclusion in this report (see Introduction): Leviathan Mine and Keno Mine. Additionally, differences
between the two studies (Table 3-1) and limited data restrict the ability to compare results to determine
the general capability for the liquid substrate anaerobic BCR technology. This is due to the Leviathan site
having 1) pretreatment with sodium hydroxide to raise influent pH from 3.1 to 4 and to precipitate some
metals (Doshi, 2006; U.S. EPA, 2006a), 2) two different operating designs (modes), and 3) that the case
study reported results for only a single sampling date for each of the two design configurations (one
when operated in a recirculation mode and one when operated in a gravity-fed mode).
3.5.1 Ranges of Applicability
Although the technology's range of applicability cannot be evaluated by comparison of solely the two
studies, maximum and minimum influent and corresponding effluent concentration data for both case
studies are provided in Table A-l, Appendix A and a limited discussion of the technology is presented in
this section. Tables 3-11 and 3-12 list the maximum and minimum influent constituent concentrations,
respectively, from comparison of data in Appendix A, Table A-l across the two operating modes at
Leviathan. Tables 3-13 and 3-14 list the maximum and minimum influent constituent concentrations,
respectively, for Keno Hill.
3-15
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Biochemical Reactors
Table 3-11: Maximum Influent and Corresponding Effluent Concentrations - Leviathan
Constituent
Maximum
Influent
Concentration
Corresponding
Effluent
Concentration
Mode
Source
All concentrations reported in mg/L; pH reported in standard units
Aluminum3
36.3
28.3
Gravity
U.S. EPA, 2006a
Arsenicb
0.0059
0.005
Recirculation
U.S. EPA, 2006a
Cadmium3
0.00042
<0.00023
Gravity
U.S. EPA, 2006a
Chromium3
0.0147
0.0139
Gravity
U.S. EPA, 2006a
Copper3
0.653
0.0676
Gravity
U.S. EPA, 2006a
Iron3
87
77.7
Gravity
U.S. EPA, 2006a
Lead3
0.0059
0.0055
Gravity
U.S. EPA, 2006a
Nickel3
0.475
0.37
Gravity
U.S. EPA, 2006a
Seleniumb
0.0114
0.0116
Recirculation
U.S. EPA, 2006a
Sulfate3
1520
1480
Gravity
U.S. EPA, 2006a
Zinc3
0.714
0.125
Gravity
U.S. EPA, 2006a
PH
3.6
4.7
Gravity
U.S. EPA, 2006a
Notes:
a = Total
b = Dissolved
Table 3-12: Minimum Influent and Corresponding Effluent Concentrations - Leviathan
Constituent
Minimum
Influent
Concentration
Corresponding
Effluent
Concentration
Mode
Source
Concentrations reported in mg/L and as dissolved, except sulfate (tota
units
); pH reported in standard
Aluminum
0.104
0.108
Recirculation
U.S. EPA, 2006a
Arsenic
0.0028
<0.0023
Gravity
U.S. EPA, 2006a
Cadmium
0.00021
0.00041
Recirculation
U.S. EPA, 2006a
Chromium
0.0118
0.012
Recirculation
U.S. EPA, 2006a
Copper
0.0057
0.0061
Gravity
U.S. EPA, 2006a
Iron
0.266
0.247
Recirculation
U.S. EPA, 2006a
Nickel
0.0117
0.0102
Recirculation
U.S. EPA, 2006a
Lead
0.0042
0.0040
Recirculation
U.S. EPA, 2006a
Selenium
0.0075
0.0114
Recirculation
U.S. EPA, 2006a
Sulfate
1160
1090
Recirculation
U.S. EPA, 2006a
Zinc
0.0063
0.0104
Recirculation
U.S. EPA, 2006a
PH
7.2
7.3
Recirculation
U.S. EPA, 2006a
3-16
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Biochemical Reactors
Table 3-13: Maximum Influent and Corresponding Effluent Concentrations - Keno Hill
Constituent
Maximum
Influent
Concentration
Corresponding
Effluent
Concentration
Mine
Source
Concentrations reported as total in mg/L
Arsenic
0.07
0.008
Keno Hilla
Harrington et al., 2015
Cadmium
0.0016
<0.0001
Keno Hilla
Harrington et al., 2015
Manganese
19
20
Keno Hilla
Harrington et al., 2015
Zinc
6.2
0.01
Keno Hilla
Harrington et al., 2015
Notes:
a = Keno Hill data used were from post-August 2009, which corresponds to the start of sulfate-
reducing conditions in the BCR; data were approximated from figures
Table 3-14: Minimum Influent and Corresponding Effluent Concentrations - Keno Hill
Constituent
Minimum
Influent
Concentration
Corresponding
Effluent
Concentration
Mine
Source
Concentrations reported as total in mg/L
Arsenic
0.018
0.001
Keno Hilla
Harrington et al., 2015
Cadmium
0.0011
<0.0001
Keno Hilla
Harrington et al., 2015
Manganese
15
16
Keno Hilla
Harrington et al., 2015
Zinc
4.8
0.055
Keno Hilla
Harrington et al., 2015
Notes:
a = Keno Hill data used were from post-August 2009, which corresponds to the start of sulfate-
reducing conditions in the BCR; data were approximated from figures
The highest constituent influent concentrations between the two operating configurations at Leviathan
(Table 3-11) show some decreases from treatment, but only copper is decreased by an order of
magnitude. Minimum influent concentrations (Table 3-12) also show little removal, with some
constituent concentrations even being increased in the effluent versus the influent (e.g., aluminum,
cadmium, copper). The liquid anaerobic BCR study at Keno Hill demonstrated that treatment can
decrease concentrations of constituents by greater than one order of magnitude for arsenic, cadmium
and zinc, at both the highest (Table 3-13) and lowest (Table 3-14) influent concentrations of the
constituents. However, manganese is not decreased by the technology. Notable differences in ranges of
applicability observed from each study further support the need for additional studies to be assessed to
evaluate applicability for the technology.
3.5.2 Average Influent and Effluent Concentrations
Average influent and effluent concentrations were not provided for either case study examined.
3-17
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Biochemical Reactors
3.5.3 Removal Efficiency
Maximum and minimum removal efficiencies for both total and dissolved concentrations of multiple
constituents were provided for the two operating modes (gravity and recirculation modes) for single
sampling dates at Leviathan, and averages were provided for Keno Hill (Appendix A, Table A-3). Table 3-
15 and Table 3-16 list the maximum and minimum removal efficiencies, respectively, as compared
across the two operating modes and two sample types at Leviathan. Table 3-17 lists the average
removal efficiencies for Keno Hill.
Table 3-15: Maximum Removal Efficiencies - Leviathan
Constituent
Maximum
Removal Efficiency
Mode
Source
Aluminum3
66.80%
Recirculation
U.S. EPA, 2006a
Cadmium3
45.20%
Gravity
U.S. EPA, 2006a
Chromium3
7.90%
Gravity
U.S. EPA, 2006a
Copperb
99.10%
Gravity
U.S. EPA, 2006a
lronb
94.60%
Recirculation
U.S. EPA, 2006a
Lead3
20.00%
Gravity
U.S. EPA, 2006a
Nickelb
83.90%
Recirculation
U.S. EPA, 2006a
Seleniumb
23.90%
Gravity
U.S. EPA, 2006a
Sulfate3
11.50%
Gravity
U.S. EPA, 2006a
Zincb
95.20%
Gravity
U.S. EPA, 2006a
Notes:
a = Total
b = Dissolved
Minimum and maximum values from Leviathan gravity flow configuration data March
24, 2004
Minimum and maximum recirculation flow configuration data August 19, 2004
Table 3-16: Minimum Removal Efficiencies - Leviathan
Constituent
Minimum
Removal
Efficiency
Mode
Source
Aluminum3
0.00%
Recirculation
U.S. EPA, 2006a
Cadmium3,b
0.00%
Recirculation and Gravity
U.S. EPA, 2006a
Chromium3b
0.00%
Recirculation and Gravity
U.S. EPA, 2006a
Copper3
-6.50%
Recirculation and Gravity
U.S. EPA, 2006a
Iron3
1.90%
Gravity
U.S. EPA, 2006a
Leadb
-9.30%
Recirculation
U.S. EPA, 2006a
Nickel3
12.80
Recirculation
U.S. EPA, 2006a
Selenium3
0.00%
Recirculation and Gravity
U.S. EPA, 2006a
Sulfateb
2.50%
Recirculation
U.S. EPA, 2006a
Zinc3
-6.60%
Recirculation
U.S. EPA, 2006a
3-18
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Biochemical Reactors
Table 3-16: Minimum Removal Efficiencies - Leviathan
Constituent
Minimum
Mode
Source
Removal
Efficiency
Notes:
a = Dissolved
b = Total
Minimum and maximum values from Leviathan gravity flow configuration data March
24, 2004
Minimum and maximum Recirculation flow configuration data August 19, 2004
Table 3-17: Average Removal Efficiencies - Keno Hill
Constituent
Average Removal
Efficiency
Mine
Source
All results reported as total
Antimony
80.00%
Keno Hill
Harrington et al., 2015
Arsenic
80.00%
Keno Hill
Harrington et al., 2015
Nickel
80.00%
Keno Hill
Harrington et al., 2015
Zinc
99.00%
Keno Hill
Harrington et al., 2015
The liquid BCRs in the case studies examined demonstrated more than 94 percent removal efficiencies
for dissolved copper, iron and zinc when influent water was previously treated with alkali (Table 3-15).
Liquid BCR treatment appears less effective for chromium, lead, selenium and sulfate than for the other
elements, with removal efficiencies <24 percent. The removal efficiency for all constituents (except for
nickel and sulfate) was also as low as zero, suggesting the removal efficiency of the liquid BCR
technology with alkali pretreatment is highly variable. On average, a liquid anaerobic BCR without an
alkaline pretreatment appears capable of providing 80 percent removal efficiency on average for total
antimony, arsenic and nickel, and an even higher 99 percent removal efficiency for total zinc (Table 3-
17). However, because of limited studies, these data may not reflect the true capabilities of a liquid
anaerobic BCR.
3.5.4 Flow Rates
U.S. EPA (2006) reported that up to 91 L/min was treated at Leviathan, whereas Harrington et al. (2015)
reported an operational flow rate ranging from 30 to 60 L/min at Keno Hill.
3.6 Capability-Aerobic, Solid Substrate
The inclusion of only one case study (Nordwick and Bless, 2008 - Surething Mine) that met the screening
criteria (Section 1.1.1) for this work limits the ability to determine general capability of aerobic BCRs.
3-19
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Biochemical Reactors
3.6.1 Ranges of Applicability
A shallow (30.5 cm (1 foot) depth) aerobic BCR decreased a maximum influent concentration of
manganese from 24 mg/L to 2.3 mg/L and a minimum influent concentration of 17 mg/L to 10.5 mg/L on
one date and to <0.30 mg/L on another date (Nordwick and Bless, 2008).1 The pH was also increased by
the limestone in the aerobic BCR and manganese removal increased as pH increased.
3.6.2 Average Influent and Effluent Concentrations
Average influent and effluent concentrations were not provided for the aerobic BCR at the Surething
Mine.
3.6.3 Removal Efficiency
Removal efficiency for the aerobic BCR part of the treatment train was not provided by Nordwick and
Bless (2008); however, using the maximum and minimum influent (see Ranges of Applicability, above),
the calculated efficiency of a manganese-oxidizing bacteria aerobic BCR ranges from about 38-98
percent.
3.6.4 Flow Rates
Flow rate specific to the aerobic BCR was not provided by Nordwick and Bless (2008); however less than
7.6 L/min was treated by the treatment train at Surething Mine.
3.7 Costs
Costs were provided for only two case studies reviewed; therefore, no technology-specific costs can be
determined. The total capital and equipment cost for the anaerobic BCR with a liquid substrate at
Leviathan was $548,431 for gravity flow mode and $554,551 for the recirculation flow mode; site
preparation costs were $288,186 and $309,568 for the gravity and recirculation flow modes,
respectively; and operational costs (including sludge disposal, analytical services for weekly sampling,
and maintenance/modification) were $104,613 and $98,353 for the gravity and recirculation flow
modes, respectively (Table 4.2 in U.S. EPA, 2006a). The first-year costs for the liquid BCR in each of the
flow-modes was approximately $190 per 3.79 m3 (1,000 gallons) of water treated (U.S. EPA, 2006a). The
construction costs for the treatment train at the Surething Mine, consisting of two anaerobic BCRs with
solid substrates, an anoxic limestone drain, and an aerobic BCR with solid substrate, was $250,000
(Doshi, 2006).
3.8 Lessons Learned
• Suitability of BCR substrate mixture for treatment at a site is best determined through bench-
scale testing. The ideal substrate consists of both long- and short-term sources of carbon and
nutrients (i.e., sources that do and do not biodegrade easily) and provides good permeability
and structural stability of the BCR over time (Bless et al., 2008; Blumenstein and Gusek, 2009). A
short-term substrate is easily biodegradable and essential for startup, while a substrate with low
biodegradation rate enhances long-term performance (Bless et al., 2008).
1 Maximum and minimum influent and effluent manganese concentrations are estimates, based on review of
Figure 4-7, SP4 and effluent post June 2004, in Nordwick and Bless, 2008.
3-20
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Biochemical Reactors
BCR system components may plug due to high iron and aluminum concentrations (Jarvis et al.,
2014; Bless et al., 2008) or due to decreased permeability or lack of stability over time (Wilmoth,
2002). Systems can incorporate design components to minimize sediment and iron hydroxide
precipitants from entering the system (Reisman et al., 2009).
Use of liquid BCRs in remote locations can be challenging due to frequent maintenance
requirements and storage of chemicals and fuel (Doshi, 2006; U.S. EPA, 2006a).
Neutralizing pH in MIW as a pretreatment step prior to circulation through an anaerobic BCR
may reduce stress on the SRB and increase metal removal efficiency in liquid and solid substrate
BCRs (U.S. EPA, 2006a; Bless et al., 2008).
Effluents from anaerobic BCR treatment may be acutely or sub-chronically toxic, although
toxicity is reduced from that observed in BCR influents (Lazorchak et al., 2002; Butler et al.,
2011). Inclusion of an aeration step following BCR treatment to remove secondary contaminants
formed through microbial activity, such as hydrogen sulfide or ammonia, and to decrease
biochemical oxygen demand may eliminate aquatic toxicity (Butler et al., 2011). Aeration is also
necessary to re-oxidize the water and precipitate and settle out any residual metals (Nordwick
and Bless, 2008; U.S. EPA, 2006a).
A shallow aerobic BCR is more effective than a deeper system for providing a sufficiently oxic
environment for manganese removal following anaerobic treatment (Nordwick and Bless, 2008).
Colder temperatures may prolong the time needed for an SRB population to become established
and may also decrease BCR efficiency (Harrington et al., 2015; Jarvis et al., 2014). However,
systems can incorporate design components to minimize the effects, such as by keeping
reactors at a depth below the frost line, providing extra capacity, covering with plastic to
insulate the cells, and controlling winter flows (Butler et al., 2011; Doshi, 2006; Wilmoth, 2002;
Blumenstein and Gusek, 2009).
Covering anaerobic BCRs with plastic may insulate the cells from low temperatures and
minimize oxygen infiltration, which leads to more reducing conditions and increased efficiency
(Wilmoth, 2002; Bless et al, 2008; Butler et al., 2011).
Solar power can be used to power pumps and monitoring equipment in locations where access
to electricity is limited, although issues may arise if persistent cloudy weather prevents
recharging of batteries (Gallagher et al., 2012; Reisman et al., 2009).
Effluent from in-situ BCRs may become re-contaminated with metals if not isolated from
untreated tunnel drainage post-treatment (Bless et al., 2008; Doshi, 2006).
Variable flows may negatively impact BCR performance (Doshi, 2006; Harrington et al., 2015).
BCR lifetime is limited by high concentrations of constituents and acidity (Doshi, 2006).
At the end of a BCR's lifetime, substrate materials that have retained the contaminants need to
be tested to determine appropriate disposal options (Jarvis et al., 2014; Doshi, 2006; U.S. EPA,
2006a).
Coarse rock materials are unable to retain zinc sulfide particulates formed in liquid BCRs
(Harrington et al., 2015). Gammons and Frandsen (2001) documented similar observations of
particulate zinc sulfide in effluent from a constructed anaerobic wetland having less coarse
substrate, as well as noting the presence of particulate copper and cadmium in effluent.
3-21
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Biochemical Reactors
3.9 References
3.9.1 Case Study References
Bless, D., Park, B., Nordwick, S., Zaluski, M., Joyce, H., Hiebert, R., and Clavelot, C. 2008. Operational
Lessons Learned During Bioreactor Demonstrations for Acid Rock Drainage Treatment. Mine Water and
the Environment, 27:241-250.
Blumenstein, E.P., and Gusek, J.J. 2009. "Overcoming the Obstacles of Operating a Biochemical Reactor
and Aerobic Polishing Cell Year Round in Central Montana." Paper presented at the 2009 National
Meeting of the American Society of Mining and Reclamation, Billings, MT, May 30 - June 5, 2009. pp.
109-129. R.I. Barnhisel (Ed.). Published by ASMR, Lexington, KY.
Butler, B.A., Smith, M.E., Reisman, D.J., and Lazorchak, J.M. 2011. Metal removal efficiency and
ecotoxicological assessment of field-scale passive treatment biochemical reactors. Environmental
Toxicology and Chemistry', 30(2):385-392.
Doshi, S.M. 2006.Bioremediation of acid mine drainage using sulfate-reducing bacteria. US
Environmental Protection Agency (U.S. EPA), Office of Solid Waste and Emergency Response and Office
of Superfund Remediation and Technology Innovation. 65 pp.
Jarvis, Adam P., Davis, Jane E., Gray, Neil D., Orme, Patrick H.A., and Gandy, Catherine. 2014. Mitigation
of Pollution from Abandoned Metal Mines, Investigation of Passive Compost Bioreactor Systems for
Treatment of Abandoned Metal Mine Discharges. Science Report Number SC090024/R3. Environment
Agency, Bristol, United Kingdom. 98 pp.
Gallagher, N., Blumenstein, E., Rutkowski, T., DeAngelis, J., Reisman, D.J., and Progess, C. 2012. "Passive
Treatment of Mining Influenced Wastewater with Biochemical Reactor Treatment at the Standard Mine
Superfund Site, Crested Butte, Colorado." Paper presented at the 2012 National Meeting of American
Society of Mining and Reclamation, Tupelo, MS, Sustainable Reclamation, June 8-15, 2012. pp. 137-153.
R.I. Barnhisel (Ed.). Published by ASMR, Lexington, KY.
Harrington, J., Harrington, J., Lancaster, E., Gault, A., and Woloshyn, K. 2015. "Bioreactor and In Situ
Mine Pool Treatment Options for Cold Climate Mine Closure at Keno Hill, YT." Paper presented at 10th
International Conference on Acid Rock Drainage and IMWA Annual Conference, Santiago, Chile, April 21-
24, 2015. 10 pp.
Jarvis, A., Gandy, C., Bailey, M., Davis, J., Orme, P., Malley, J., Potter, H., and Moorhouse, A. 2015. "Metal
Removal and Secondary Contamination in a Passive Metal Mine Drainage Treatment System." Paper
presented at 10th International Conference on Acid Rock Drainage and IMWA Annual Conference,
Santiago, Chile, April 21-24, 2015. 9 pp.
Lazorchak, J.M., Smith, M.E., Bates, E., and Wilmoth, R. 2002. Poster presented at the U.S. EPA Hardrock
Mining Conference, Westminster, Colorado, May 7-9, 2002.
Nordwick, S., Zaluski, M., Park, B., and Bless, D. 2006. "Advances in Development of Bioreactors
Applicable to the Treatment of ARD." Paper presented at the 7th International Conference on Acid Rock
Drainage (ICARD), St. Louis, MO, March 26-30, 2006. pp. 1410-1420. R.I. Barnhisel (Ed.), Published by
ASMR, Lexington, KY.
3-22
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Biochemical Reactors
Nordwick, S. and D. R. Bless. 2008. Final Report-An Integrated Passive Biological Treatment System.
U.S. Environmental Protection Agency, Mine Waste Technology Program Report #16. (EPA/600/R-
09/158). 46 pp.
Reisman, D., Rutkowski, T., Smart, P., Gusek, J. and Sieczkowski, M. 2009. "Passive Treatment and
Monitoring at the Standard Mine Superfund Site, Crested Butte, CO." Paper presented at the 2009
National Meeting of American Society of Mining and Reclamation, Billings, MT, Revitalizing the
Environment: Proven Solutions and Innovative Approaches May 30 -June 5, 2009, pp. 1107-1128. R.I.
Barnhisel (Ed.), Published by ASMR, Lexington, KY.
U.S. Environmental Protection Agency (U.S. EPA). 2006a. Compost-Free Bioreactor Treatment of Acid
Rock Drainage, Leviathan Mine, California Innovative Technology Evaluation Report. (EPA/540/R-
06/009). 82 pp.
U.S. Environmental Protection Agency (U.S. EPA). 2002. Final Report - Sulfate-Reducing Bacteria
Reactive Wall Demonstration, Mine Waste Technology Program Activity IIIProject 12 by Wilmoth, R.
(EPA/600/R-02/053). 69 pp.
3.9.2 General BCR References
Blais, J.F., Djedidi, Z., Cheikh, R. Ben, Tyagi, R.D., and Mercier, G. 2008. Metals precipitation from
effluents: Review. Journal of Hazardous, Toxic, and Radioactive Waste, 12(3):135-149.
Gammons, C.H. and Frandsen, A.K. 2001. Fate and transport of metals in H2S-rich waters at a treatment
wetland. Geochemical Transactions 2:1-15.
Gusek, J.J. 2002. "Sulfate-Reducing Bioreactor Design and Operating Issues: Is This the Passive
Treatment Technology for Your Mine Drainage?" In Proceedings of the National Association of
Abandoned Mine Land Programs, Park City, Utah, September 15-18, 2002. 14 pp.
Hedin, R., Weaver, T., Wolfe, N., and Watzlaf, G. 2013. "Effective Passive Treatment of Coal Mine
Drainage." Presented at the 35th Annual National Association of Abandoned Mine Land Programs
Conference, Daniels, West Virginia, September 23, 2013. 13 pp.
Interstate Technology & Regulatory Council (ITRC) Biochemical Reactors for Mining-Influenced Waste
Team. 2013. Biochemical Reactors for Treating Mining- Influenced Water. BCR-1. Washington, D.C.. 361
pp. http://www.itrcweb.org/bcr-l/.
3-23
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Caps and Covers
4 Caps and Covers
Caps and covers are well-proven technologies that are often employed at mine sites. Typically, caps and
covers are used to isolate solid mining waste to prevent or limit infiltration of water, ingress of oxygen,
control dust migrations, prevent erosion and eliminate the potential for direct contact with the waste.
Decreased infiltration from use of caps and covers could decrease loads of constituents sufficiently to
allow for passive treatment. While not directly treatment technologies, studies were sought where caps
and covers influenced leachate concentrations. Various materials are utilized for caps and covers,
including soil, clay, amendments, membrane liners and rock, vegetation, as well as a combination of
these materials based on the conditions and needs at specific mine sites (Interstate Technology and
Regulatory Council [ITRC], 2010).
4.1 Case Studies Evaluated
This chapter provides an evaluation of case studies in which caps and covers were the primary
components in treating or managing mining wastes to mitigate mining-influenced water (MIW)
formation. The case studies were selected based on the criteria presented in Section 1.1.1. Due to the
frequent use of liners, few studies are available where the influence of cap or cover can be isolated from
the influence of a liner. The case studies examined include three mining sites: one in the United States,
one in Australia and one in Sweden. Table 4-1 summarizes site names and locations, treatment design
information, and references for each of the case studies. The Dunka Mine case study (Eger and Eger,
2005) examined the effectiveness of wetland treatment combined with capping of waste piles; data
incorporated into this chapter's evaluation address the capping component, whereas the Constructed
Wetlands chapter (Section 7) addresses the whole system. The chapter presents technology-wide
considerations for constraints, treatability of contaminants, capability, technological and site-specific
requirements, and lessons learned for caps and covers from evaluation of case study results.
Table 4-1: Caps and Covers Case Study Sites
Site Name
Type
Description
Study Type
Reference
Reference Type
and Location
Kristineberg
Composite
Sewage sludge
Pilot scale
Nason et al.,
Journal paper
Mine,
cover
was used as a
2013*
Northern
consisting of
sealing layer in a
Nason, 2013
Conference
Sweden
till
composite dry
proceedings
(protective
cover. Composite
Nason et al.,
Conference
layer) and
dry covers consist
2010
proceedings
sewage
of a protective
sludge
layer and a
(sealing
sealing layer.
layer)
4-1
-------
Caps and Covers
Table 4-1: Caps and Covers Case Study Sites
Site Name
Type
Description
Study Type
Reference
Reference Type
and Location
Savage River
Water-
To control acid
Full scale
Li et al., 2012*
Conference
Mine,
shedding top
rock drainage
proceedings
Tasmania,
cover and
(ARD), a
Australia
alkaline
(calcite-
chlorite
schist) side
cover
combined water-
shedding and
calcite-chlorite
schist cover was
placed over a
historic dump (B-
dump).
Dunka Mine,
Several
Five waste rock
Full scale
Eger and Eger,
Conference
Northeastern
covers
stockpiles were
2005*
proceedings
Minnesota
consisting of
screened
covered.
Eger et al.,
1998
Conference
proceedings
soil,
Eger et al.,
Conference
compacted
1996
proceedings
soil and/or
flexible
membrane
liner
Notes:
*Primary source(s) of data for evaluation in this chapter
4.2 Constraints
A constraint for caps and covers is the cost for locating, excavating and transporting capping and
covering materials to the site being remediated (Nason et al., 2013), with higher transportation costs
associated with materials located far from the site (Eger et al., 1998). A limitation to using sewage
sludge in cap and cover material is that it is chemically unstable and may contain metals or nitrate that
could be leached (Nason, 2013). Another limitation to using sewage sludge is degradation of the organic
matter that would limit the long-term capability of the cap, or potential for sewage sludge to contain
emerging contaminants that may need to be tested (Nason, 2013).
4.3 Treatable Contaminants
Caps and covers in the studies examined are capable of increasing pH and decreasing the concentrations
of dissolved cadmium, copper, iron, lead, sulfur, and zinc, and cobalt, copper, nickel, and zinc in
leachate/seepage not indicated as total or dissolved (Eger and Eger, 2005; Nason et al., 2013) relative to
pre-capping conditions. Additionally, capping demonstrated a reduction in oxidation of sulfide from
waste rock (Li et al., 2012).
4-2
-------
Caps and Covers
4.4 Capability
The three case studies meeting the criteria (Section 1.1.1) differed in the type of materials used for the
covers, methodologies for monitoring effectiveness (two analyzed leachate samples, one analyzed
waste material). These differences between the studies and limited data reported restrict the ability to
compare directly across types of caps/covers. The limited numbers of studies identified limits the
assessment of general capability of caps and covers.
4.4.1 Ranges of Applicability
Range of applicability differs in this section, as compared to technologies directly treating water,
because results are not based on an influent treated and a corresponding effluent attained at a point in
time, but rather are based on differences in concentrations of constituents in affected water sources
monitored before and after cap/cover placement or capped versus uncapped wastes. Therefore,
applicability is presented as a range in concentrations in leachate before treatment (pre-capping or
uncapped control) and a range attained after covering of the waste. Only one examined case study
provided non-averaged pre-and post-capping (or capped versus uncapped control) concentration data
to address range of applicability and Table 4-2 contains the concentration ranges for constituents from
Table B-l in Appendix B.
Table 4-2: Concentration Range Pre- and Post-Capping - Kristineberg Mine
Constituent
Pre-Capping (or Uncapped
Control) Concentration
Range
Post-Capping
Concentration
Range
Media
Source
Concentrations reported as dissolved in mg/L; pH reported in standard units
Cadmium
ND - 0.03
ND
Leachate
Nason et al., 2013
Copper
0.0005-0.04
ND-0.001
Leachate
Nason et al., 2013
Iron
ND-0.022
ND-0.005
Leachate
Nason et al., 2013
Lead
0.0001-0.00065
0.0001-
0.00055
Leachate
Nason et al., 2013
Sulfur
410-700
15 - 220
Leachate
Nason et al., 2013
Zinc
2.5-40
ND
Leachate
Nason et al., 2013
PH
6.2-7.6
6.8-8.2
Leachate
Nason et al., 2013
Notes:
ND = Not detected
Nason et al. (2013) compared capped cells with uncapped control cells
Table 4-2 shows that the cap at the single case study examined that provided pre- and post-capping
concentration ranges can decrease concentrations of cadmium, copper, iron, lead, sulfur, and zinc
originating from mining wastes. The magnitude of decrease in concentrations in affected leachate varies
among the constituents assessed. The cap in the case study examined also can raise the pH of affected
water as shown by comparison of the lowest pH of leachate in the absence of a cap on the waste source
with the lowest pH of the leachate after placement of a cap on the waste material source and likewise
comparison of the highest pH values in the leachate.
4-3
-------
Caps and Covers
While caps/covers do result in decreased concentrations in affected water sources, a general
assessment of applicability of the technology is hindered by data limitations. For example, only dissolved
cadmium, copper, iron, lead, zinc, and pH were monitored in the single study examined that provided
pre- and post-capping concentration ranges.
4.4.2 Average Pre-Treatment and Post-Treatment Concentrations
This chapter includes a single study that documented average concentrations. Table 4-3 lists the
maximum average pre-capping leachate concentrations and the range in average post-capping
concentrations (average 1996-1998 and average 1999-2004) and Table 4-4 lists the minimum average
pre-capping leachate concentrations and the average post-capping concentrations (1996-1998) for
cobalt, copper, nickel, and zinc. Values were determined by looking across data in Appendix B, Table B-2,
which includes data from pre- and post-capping of two waste piles.
Table 4-3: Maximum Average Pre-Capping Leachate and Post-Capping Leachate Concentration
Range (1996-1998 -1999-2004) - Dunka Mine
Constituent
Maximum
Average Pre-
Capping
Leachate
Concentration
Average Post-
Capping Leachate
Concentration
Range
Stockpile/Wetland
Source
Concentrations reported in mg/L, total or dissolved not specified; pH reported in standard units
Cobalt
0.036
0.009a
8018 and
8031/W1D
Eger and Eger, 2005
Copper
0.068
0.02-0.03
8018 and
8031/W1D
Eger and Eger, 2005
Nickel
3.98
0.74-0.76
8018 and
8031/W1D
Eger and Eger, 2005
Zinc
0.052
0.019-0.021
8018 and
8031/W1D
Eger and Eger, 2005
PH
7
7
8031/W2D/3D
Eger and Eger, 2005
Notes:
a = No value given in source for 1999-2004
Post-capping values are influent concentrations to Wetland W1D from Table 1 of the source
Table 4-4: Minimum Average Pre-Capping Leachate and Post-Capping Leachate Concentrations
(1996-1998) - Dunka Mine
Constituent
Minimum
Average Pre-
Capping
Leachate
Concentration
Average Post-
Capping Leachate
Concentration
Stockpile/Wetland
Source
Concentrations reported in mg/L, total or dissolved not specified; pH reported in standard units
Cobalt
0.02
0.02
8031/W2D/3D
Eger and Eger, 2005
Copper
0.05
0.05
8031/W2D/3D
Eger and Eger, 2005
4-4
-------
Caps and Covers
Table 4-4: Minimum Average Pre-Capping Leachate and Post-Capping Leachate Concentrations
(1996-1998) - Dunka Mine
Constituent
Minimum
Average Pre-
Capping
Leachate
Concentration
Average Post-
Capping Leachate
Concentration
Stockpile/Wetland
Source
Concentrations reported in mg/L, total or dissolved not specified; pH reported in standard units
Nickel
1.9
1.9
8031/W2D/3D
Eger and Eger, 2005
Zinc
0.05
0.05
8031/W2D/3D
Eger and Eger, 2005
PH
7.07
7.26-7.3
8018 and
8031/W1D
Eger and Eger, 2005
Although they are not directly comparable (i.e., a given maximum average pre-capping concentration in
affected water may not result in a given minimum average post-capping concentration in affected
water), on average, cobalt and nickel concentrations are an order of magnitude (Table 4-3) lower than
average pre-capping leachate concentrations. Copper and zinc decreased by less than an order of
magnitude, on average. Minimum average pre-capping data are identical to average post-capping data
(Table 4-4), suggesting that this cap was not effective.
Table 4-5 presents a comparison of the percentage of total sulfur in waste rock materials five years after
being capped or not capped, as compared to the initial conditions.
Table 4-5: Savage River Mine - Percent Total Sulfur in Waste Rock, Pre-Cover, Post-Cover and
with No Cover Within The B-Dump
Under
Alkaline
Cover
No Cover
Pre-Cover
Source
Average Percentage of
Total Sulfur (%)
1.9
0.9
3.2a
Li et al., 2012
MPA (Sulfur)
57.1
27.2
97.2
Li et al., 2012
Decrease in Percentage
of Total Sulfur between
2005 and 2010 (%)
41
72
Li et al., 2012
Notes:
Table reproduced from Table 5 in source
MPA = maximum potential acidity expressed as kg H2S04/t
a = Li et al. (2012) calculated the average sulfur percentage from three samples collected in May
2005; the total sulfur content in the three samples was 3.05 percent, 3.77 percent and 2.71 percent
On average (over five years), and assuming that sulfur-bearing waste materials are completely
homogenized within the waste rock pile and that any oxidized sulfur is leached out of the pile and not
retained as precipitated salts (Li et al., 2012), capping with an alkaline cover is effective in decreasing
4-5
-------
Caps and Covers
oxidation of pyritic waste rock as seen by the higher percentage of sulfur remaining in the samples
obtained under the alkaline cover Table 4-5).
Capping led to 31 percent less oxidation of pyrite as compared to waste rock without a cap, when both
were compared to pre-capping conditions. This is reflected also in the capped material retaining more
potential acidity (57.1 kilograms (kg) H2S04/t) than the un-capped waste rock (27.2 kg H2S04/t) (Table 4-
5).
4.4.3 Percentage Reduction
Table 4-6 presents percentage reductions in concentrations of constituents in leachate from
capping/covering of the mine waste source. The maximum and minimum percentage reductions were
calculated from the data in Appendix B, Tables B-l and B-2. Percentage reduction was only calculated
when a detected concentration was available for the pre-reclamation condition. The percentage
reductions should be considered estimates due to the variability in comparing data from capped and
uncapped and pre- and post-reclamation conditions obtained in different time periods.
Table 4-6: Maximum and Minimum Percentage Reduction
Constituent
Water
Sample
Maximum
Percentage
Reduction
Minimum
Percentage
Reduction
Mine
Notes
Cadmium
Dissolved
>99.00%
>99.00%
Kristineberg3
Table B-l
Copper
Dissolved
>99.00%
97.5%
Kristineberg3
Table B-l
Iron
Dissolved
>99.00%
77.27%
Kristineberg3
Table B-l
Lead
Dissolved
84.62%
0.00%
Kristineberg3
Table B-l
Sulfur
Dissolved
97.86%
46.34%
Kristineberg3
Table B-l
Zinc
Dissolved
>99.00%
>99.00%
Kristineberg3
Table B-l
Cobalt
NS
75.00%
75.00%b
Dunkac
Table B-2
(Wetland W1D)
Copper
NS
70.59%
55.88%
Dunkac
Table B-2
(Wetland W1D)
Nickel
NS
81.41%
80.90%
Dunkac
Table B-2
(Wetland W1D)
Zinc
NS
63.46%
59.62%
Dunkac
Table B-2
(Wetland W1D)
Notes:
NA = Pre-reclamation concentrations were not detected
NS = Not stated
a = EPA calculated maximum and minimum percent reduction based on the maximum and minimum
leachate concentrations in capped and uncapped cells shown in Appendix B, Table B-l. For
4-6
-------
Caps and Covers
Table 4-6: Maximum and Minimum Percentage Reduction
Constituent
Water
Sample
Maximum
Percentage
Reduction
Minimum
Percentage
Reduction
Mine
Notes
constituents that were not detected in the uncapped cell, EPA assumed a greater than 99 percent
reduction.
b = Cobalt concentrations in 1999-2004 were not recorded, so only a single set of average pre- and
post-capping concentrations were available
c = EPA calculated maximum and minimum percent reduction based on pre-capping average
concentrations (1992-1994) and post-capping average concentrations (1996-1998 and 1999-2004) for
Wetland W1D shown in Appendix B, Table B-2
Table 4-6 shows that cap/cover placement can reduce concentrations of constituents in affected water
sources in the case studies that provided data to calculate percentage reduction and when pre-
reclamation concentrations were reported above detection limits. The magnitude of the percentage
reduction in affected water sources varies among the constituents and case studies. The range of
percentage reduction for constituents within individual case studies also varies. Maximum percentage
reduction for all constituents in all case studies included in the evaluation in Table 4-6 was greater than
63 percent; minimum percentage reduction for all constituents in all case studies included in the
evaluation in Table 4-6 was greater than 50 percent except for dissolved lead and dissolved sulfur in one
study (0 percent and 46 percent reduction, respectively, at Kristineberg).
4.4.4 Flow Rates
Only one case study that was evaluated had flow rates for water flow out of a capped area (Table 4-7).
Average flow from capped stockpiles ranged from 38 liters per minute (L/min) to about 76 L/min (Eger
and Eger, 2005). Flow rates were decreased by 36 percent for part of the year (May through October)
after two years of the cap being in place covering about 60 percent of the total area of the stockpile for
W1D (Eger and Eger, 2005).
Table 4-7 Average Flow
Average Flow
Stockpile
Pre- or Post-Capping
Date Range
All rates are in L/min
75
W2D/3D
Pre-capping (1992-1994)
125
W1D
Pre-capping (1992-1994)
45
W2D/3D
Post-capping (1996-1998)
57
W1D
Post-capping (1996-1998)
45
W2D/3D
Post-capping (1999-2004)
38
W1D
Post-capping (1999-2004)
Notes:
Source: Eger and Eger, 2005
4-7
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Caps and Covers
4.5 Costs
Costs were provided in only one of the three case studies. Cost per hectare averaged $35,000 for a
screened soil cap and was $123,000 for a flexible liner (Eger et al., 1998). Other cap types presented in
Eger et al. (1998) included compacted soil at $56,000 per hectare and a combined screened soil and
flexible liner at $54,000 per hectare; however, these cap types did not have associated data provided in
the case study. Costs are contingent upon site-specific details (e.g. earth moving, contour and grade).
4.6 Lessons Learned
• When using sewage sludge as a sealing layer in a composite cover, degradation of the organic
matter in the sludge may limit the length of time a cap or cover is effective and further study of
long-term applicability is needed (Nason et al., 2013).
• To prevent pyrite oxidation and formation of a contaminant plume, sewage sludge should be
avoided on water-saturated cover types (Nason, 2013).
• Applying sewage sludge to fresh tailings can lead to cracking and can release additional metals
into the tailings (Nason, 2013).
4.7 References
4.7.1 Case Study References
Eger, P., Wagner, J., and Melchert, G. 1996. "The Use of Overland Flow Wetland Treatment Systems to
Remove Nickel from Neutral Mine Drainage. "Paper presented at the 1996 Annual Meeting of the
American Society for Surface Mining and Reclamation (ASSMR), Knoxville, TN, May 18-23. pp. 580-589.
Eger, P., Melchert, G., and Wagner, J. 1998. "Mine closure - Can passive treatment be successful." In
Proceedings of 15th Annual Meeting of American Society for Surface Mining and Reclamation, St. Louis,
MO, May 17-21, 1998. pp. 263-271.
Eger, P. and P. Eger. 2005. "Controlling Mine Drainage Problems in Minnesota - Are All the Wetland
Treatment Systems Really Above Average?" Paper presented at the 2005 National Meeting of the
American Society of Mining and Reclamation, June 19-13, 2005. Published by ASMR, Lexington, KY. pp.
339-359.
Li, J., Kawashima, N., Kaplun, K., Schumann, R.C, Smart, R., Hughes, A, Hutchison, B., and Kent, S. 2012.
"Investigation of alkaline cover performance for abatement of ARD from waste rock dumps at Savage
River." Presented at the 9th International Conference on Acid Rock Drainage (ICARD), Ottawa, Canada,
May, 2012. pp. 418-429.
Nason, P. 2013. "Advances in using sewage sludge to remediate sulfidic mine tailings - an overview from
pilot- and field-scale experiments, Northern Sweden." In Wolkersdorfer, C., Brown, A., and Figueroa, L.
(Eds.), Proceedings of the International Mine Water Association Annual Conference: Reliable Mine
Water Technology, Volume 1. Golden, CO, August 6-9, 2013. pp. 681-686. Published by the International
Mine Water Association.
Nason, P., Alakangas, L., and Ohlander, B. 2010 "The Effectiveness of Using Sewage Sludge as a Sealing
Layer on Sulphide-rich Mine Tailings: A Pilot-scale Experiment, Northern Sweden." In proceedings from
the International Mine Water Association Symposium: Mine Water and Innovative Thinking, Sydney,
4-8
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Caps and Covers
Nova Scotia, September 5-9, 2010. pp. 155-158. Published by Cape Breton University Press, Sydney,
Nova Scotia.
Nason, P., Alakangas, L., and Ohlander, B. 2013. Using Sewage Sludge as a Sealing Layer to Remediate
*Sulphidic Mine Tailings: A Pilot-Scale Experiment, Northern Sweden. Environmental Earth Sciences
70(7): 3093-3105.
4.7.2 General Capping References
Interstate Technology & Regulatory Council (ITRC) Interstate Technology & Regulatory Council, Mining
Waste Team. 2010. "Technology Overview, Capping, Covers and Grading." Last modified August 2010.
https://www.itrcweb.org/miningwaste-guidance/to capping covers.htm.
4-9
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Neutralization and Chemical Precipitation
5 Neutralization and Chemical Precipitation
Neutralization and chemical precipitation involve the use of reagents to facilitate the formation of
insoluble solids from the mining-influenced water (MIW) that then can be separated from the treated
water. Alkaline reagents used for treating MIW include limestone (CaC03), lime (CaO), hydrated (or
slaked) lime (CaOH2), sodium hydroxide (NaOH), and soda ash (Na2C03). Neutralization and chemical
precipitation can occur in an active water treatment system or in a passive or semi-passive, flow-
through system. In active systems, coagulants and flocculants often are added to facilitate faster
separation of the solids from the water column, whereas in passive or semi-passive systems, settling
typically occurs over time in a pond or wetland without using additional chemicals. Biogenically-
produced or chemical sulfide reagents may be used in active treatment systems to anaerobically
precipitate metal sulfides that may be salable (Kratochvil et al, 2015). The active and semi-passive
systems evaluated in this chapter utilized hydroxide precipitation with lime. Although active sulfide
precipitation technology is being used, at the time of report development no studies using it were
identified that met the criteria (see Section 1.1.1) for this work; therefore, that technology was not
evaluated.
Passive alkaline neutralization and precipitation treatment systems include anoxic limestone drains
(ALD) and reducing and alkalinity producing systems (RAPS) that use limestone to neutralize acidity and
provide the alkalinity to allow for precipitation of metals in a settling pond or other structure
downstream from the limestone system. Variations in system designs have been explored to reduce
passivation or clogging, save space or otherwise improve on the mechanisms of treatment. The passive
system evaluated in this chapter uses a dispersed alkaline substrate (DAS). The DAS is a medium that
consists of a fine-grained alkaline material such as calcite, limestone sand or magnesium oxide (MgO)
mixed with a coarse inert material such as wood chips (Rotting et al., 2008a; Rotting et al., 2008b;
Macfas et al., 2012a). The small grain size of the alkaline material increases reactivity and reduces
passivation with its large reactive surface area, while the coarse material provides porosity and reduces
potential for clogging, although clogging may occur if the MIW being treated has high concentrations of
aluminum (Rotting et al., 2008a). Limestone-based DAS effectively treats trivalent metals aluminum and
iron and MgO-based DAS effectively treats divalent metals like copper, manganese, nickel and zinc
(Macfas et al., 2012b), which precipitate at higher pH than ferric iron and aluminum.
5.1 Case Studies Evaluated
This chapter provides an evaluation of case studies in which neutralization and chemical precipitation
was a primary component of MIW treatment. The case studies evaluated were selected based on the
criteria presented in Section 1.1.1 and include three active lime treatment systems (one of which was
operated in two separate modes and one that utilized a Rotating Cylinder Treatment System™ (RCTS)), a
semi-passive system and a passive limestone DAS (Table 5-1). This chapter provides considerations for
constraints, treatability of contaminants, capability, technological and site-specific requirements, costs
and lessons learned for neutralization and chemical precipitation treatment from evaluation of these
case studies.
5-1
-------
Neutralization and Chemical Precipitation
Table 5-1: Neutralization and Chemical Precipitation Case Study Sites
Site Name
Type
System
Study Type
Reference
Reference
and Location
Description
Type
Leviathan
Active lime
Two modes
Pilot scale
U.S. EPA,
Report
Mine,
treatment
employed: single-
2006a*
Alpine
stage and dual-
County,
stage mode (1st
California
stage for arsenic
removal and 2nd
stage for
removing
remaining
constituents)
Semi-passive
Continuous flow
alkaline lagoon
lime contact
system
Britannia
Active lime
High-density
Full scale
Madsen et
Conference
Mine,
treatment
sludge (HDS)
al., 2012*
proceedings
Vancouver,
British
Columbia
Monte
Passive limestone
Two, three-cubic
Pilot scale
Macfas et al.,
Journal
Romero Mine
DAS
meter tanks (Tank
2012a*
paper
Southwestern
1 and Tank 2)
Macfas et al.,
Journal
Spain
filled with coarse
2012b
paper
wood chips mixed
Rotting et al.,
Journal
with limestone
2008a
paper
sand and
operated in series
separated by two
aeration cascades
and two
decantation
ponds
Elizabeth
Active lime
An RCTS™ system
Full scale
Butler and
Report
Mine,
treatment in
followed by a
Hathaway,
Strafford,
Rotating Cylinder
sedimentation
2020*a
Vermont
Treatment
System™ (RCTS)
basin
Notes:
*Primary source(s) of data for evaluation in this chapter
a. Although published outside of the established literature search timeframe, report is included due to
its authors' involvement in drafting this report.
The DAS at Monte Romero Mine was part of a larger treatment train, which consisted of water flowing
from the mine shaft to a natural Fe-oxidizing lagoon (NFOL) to reduce high iron concentrations, followed
5-2
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Neutralization and Chemical Precipitation
by a limestone-DAS tank, two aeration structures and settling ponds, a second limestone-DAS tank
followed by two more aeration structures and settling ponds, and then to a MgO-DAS tank (Macfas et
al., 2012b). The multi-step system is evaluated in the Treatment Trains chapter (Section 10). This
chapter evaluates only the two limestone-DAS tanks (Tank 1 and Tank 2). Water quality data specific to
the MgO-DAS tank were unavailable in the references reviewed.
5.2 Constraints
A constraint for typical active lime treatment systems is that they require a large amount of space to
store sludge, water and other reagents, as well as filter presses, pumps and piping (U.S. EPA, 2006a). The
RCTS™ system is more compact and does not require conventional agitators, compressors, diffusers and
reactions vessels (Butler and Hathaway, 2020). Utilities such as electricity are required to operate the
systems and cellular or satellite phone service may be required to monitor remote sites (U.S. EPA,
2006a). Active lime treatment also requires high maintenance and regular monitoring, and systems are
prone to scaling from gypsum formation (CaS04*2H20) and plugging from clumps of lime (U.S. EPA,
2006a; Butler and Hathaway, 2020). Lime treatment may also increase pH above regulatory limits for
discharge to receiving waters; secondary treatment to decrease pH may be needed to meet water
quality criteria. Additionally, capacity can be limited in the treatment system and high flow events may
occur, leaving some MIW untreated or unable to meet effluent limits (Madsen, et al., 2012).
In cold climates, operation may not be possible in winter months, requiring yearly shutdown procedures
which are time-consuming and intensive, or alternatively requiring the treatment system to be housed
in a heated structure, increasing costs and energy usage (Butler and Hathaway, 2020). Climate also may
influence land space required for the system if a large holding pond is needed to accommodate both
MIW and precipitation. Operation in remote areas requires increased planning and organization (U.S.
EPA, 2006a).
A constraint of the DAS technology is that precipitates accumulate in the tanks containing the substrate
and this eventually causes clogging, which will lead to a need to either remove surface precipitates or to
replace the substrate (Rotting et al., 2008a). According to Rotting et al. (2008a), the need to remove
precipitates or replace substrate will occur more frequently than in a RAPS or ALD.
5.3 Treatable Contaminants
Lime treatment can increase pH and treat aluminum, arsenic, cadmium, chromium, copper, iron, lead,
manganese, nickel, selenium and zinc (U.S. EPA, 2006a; Madsen et al., 2012; Butler and Hathaway,
2020). Semi-passive alkaline treatment also can reduce concentrations of aluminum, arsenic, chromium,
copper, iron, lead, nickel, selenium and zinc and increase pH (U.S. EPA, 2006a). Limestone-DAS can treat
aluminum, arsenic, copper, iron, lead, silicon, zinc and increase pH (Macfas et al., 2012a). Future case
study comparisons may provide additional information on treatable contaminants.
5.4 Capability - Active
Because only three studies were identified that met the screening criteria, limited data restrict the
ability to determine the general capability for active lime treatment.
5-3
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Neutralization and Chemical Precipitation
5.4.1 Ranges of Applicability
Two case studies included corresponding influent and effluent data. Concentrations of metals tend to be
inversely related to the pH, with higher concentrations associated with a lower pH and lower
concentrations associated with a higher pH. Tables 5-2 and 5-3 show the maximum influent
concentration (and the minimum pH) and corresponding effluent concentration, and the minimum
influent concentration (and the maximum pH) and corresponding effluent concentration, respectively
from comparison of data in Table C-l, Appendix C.
Table 5-2: Maximum Influent and Corresponding Effluent Concentrations - Active Treatment
Constituent
Maximum
Influent
Concentration
Corresponding
Effluent
Concentration
Mine / Mode
Source
Concentrations reported in mg/L and as dissolved, except iron is reported as total; pH reported in
standard units
Aluminum
486
1.09
Leviathan/Dual-stage
U.S. EPA, 2006a
Arsenic
4.05
0.0101
Leviathan/Dual-stage
U.S. EPA, 2006a
Cadmium
0.0683
0.0007
Leviathan/Dual-stage
U.S. EPA, 2006a
Chromium
1.24
0.0024
Leviathan/Dual-stage
U.S. EPA, 2006a
Copper
2.99
0.0101
Leviathan/Dual-stage
U.S. EPA, 2006a
Iron
1,710
23.6a
Elizabeth Mine
Butler and
Hathaway, 2020
Lead
0.0122
<0.0014
Leviathan/Dual-stage
U.S. EPA, 2006a
Nickel
8.77
0.0389
Leviathan/Dual-stage
U.S. EPA, 2006a
Selenium
0.0323
<0.0018
Leviathan/Single-stage
U.S. EPA, 2006a
Zinc
1.81
0.0307
Leviathan/Dual-stage
U.S. EPA, 2006a
PH
4.63
8.65a
Elizabeth Mine
Butler and
Hathaway, 2020
Notes:
Dual-stage data come from 12 sampling dates in 2002 and 1 in 2003 and the single-stage data come
from 7 sampling dates in 2003
a = Effluent data from the RCTS™
system
Table 5-3: Minimum Influent and Corresponding Effluent Concentrations - Active Treatment
Constituent
Minimum
Influent
Concentration
Corresponding
Effluent
Concentration
Mine / Mode
Source
Concentrations reported in mg/L, and as dissolved, except iron is reported as total; pH reported in
standard units
Aluminum
98.6
0.575
Leviathan/Single-stage
U.S. EPA, 2006a
Arsenic
1.33
0.0096
Leviathan/Dual-stage
U.S. EPA, 2006a
Cadmium
0.0132
<0.00021
Leviathan/Single-stage
U.S. EPA, 2006a
Chromium
0.266
0.0116
Leviathan/Single-stage
U.S. EPA, 2006a
Copper
0.434
<0.0019
Leviathan/Single-stage
U.S. EPA, 2006a
5-4
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Neutralization and Chemical Precipitation
Table 5-3: Minimum Influent and Corresponding Effluent Concentrations - Active Treatment
Constituent
Minimum
Influent
Concentration
Corresponding
Effluent
Concentration
Mine / Mode
Source
Concentrations reported in mg/L, and as dissolved, except iron is reported as total; pH reported in
standard units
Iron
50
4a
Elizabeth Mine
Butler and
Hathaway, 2020
Lead
0.0017
0.0044
Leviathan/Dual-stage
U.S. EPA, 2006a
Nickel
2.41
0.0688
Leviathan/Single-stage
U.S. EPA, 2006a
Selenium
0.0046
0.0037
Leviathan/Dual-stage
U.S. EPA, 2006a
Zinc
0.49
0.0031
Leviathan/Single-stage
U.S. EPA, 2006a
PH
6.87
9.6a
Elizabeth Mine
Butler and
Hathaway, 2020
Notes:
Dual-stage data come from 12 sampling dates in 2002 and 1 in 2003 and the singl
e-stage data come
from 7 sampling dates in 2003
a = Effluent from the RCTS™ system
Active lime treatment can decrease concentrations of all constituents evaluated, with concentrations of
aluminum, arsenic, cadmium, chromium, copper, iron, nickel and zinc decreased by two to three orders
of magnitude when starting concentrations are high, and lead and selenium can be decreased to below
their respective detection limits (Table 5-2). Active lime treatment can also increase pH.
Decreases in aluminum, arsenic, cadmium, copper and nickel concentrations are also two or three
orders of magnitude from minimum concentrations treated, whereas chromium and iron concentrations
are decreased by one order of magnitude (Table 5-3). The lowest influent lead concentration increased
following treatment, but influent and effluent concentrations are on the same order of magnitude as
the detection limit (0.0014 mg/L, Table 5-2) and therefore may not be representative of treatment
ability. It should be noted that the minimum concentrations of many constituents indicated in Table 5-3
are higher than low concentrations present at many other sites; therefore, the table likely does not
represent the capability of lime treatment at lower influent concentrations.
5.4.2 Average Influent and Effluent Concentrations
Tables 5-4 and 5-5 list the highest and lowest average influent concentrations treated for each
constituent, respectively. Tables 5-6 and 5-7, respectively, list the highest and lowest average effluent
concentrations attained for each constituent. These values were determined by comparing values in
Appendix C, Table C-2. It is important to note that the average influent concentrations do not
correspond directly with the average effluent concentrations (see Section 1.1.2).
5-5
-------
Neutralization and Chemical Precipitation
Table 5-4: Maximum Average Influent Concentration Treated - Active Treatment
Constituent
Maximum
Average
Influent
Concentration
Average Effluent
Concentration
Mine / Mode
Source
Concentrations reported in mg/L and as dissolved, except iron is reported as total; pH reported in
standard units
Aluminum
381
1.118
Leviathan/Dual-stage
U.S. EPA, 2006a
Arsenic
3.236
0.0063
Leviathan/Single-stage
U.S. EPA, 2006a
Cadmium
0.097
0.001
Britannia
Madsen et al., 2012
Chromium
0.877
0.0057
Leviathan/Dual-stage
U.S. EPA, 2006a
Copper
16.8
0.01
Britannia
Madsen et al., 2012
Iron
879.55 ±
181.09
0.37 ± 0.29a
Elizabeth Mine
Butler and
Hathaway, 2020
Lead
0.0082
0.002
Leviathan/Dual-stage
U.S. EPA, 2006a
Manganese
4.8
0.3
Britannia
Madsen et al., 2012
Nickel
7.024
0.0342
Leviathan/Dual-stage
U.S. EPA, 2006a
Selenium
0.0271
0.00214
Leviathan/Single-stage
U.S. EPA, 2006a
Zinc
19.7
0.03
Britannia
Madsen et al., 2012
PH
3.71
9.2b
Britannia
Madsen et al., 2012
Notes:
a = Effluent from the RCTS™ system
b = The average effluent pH was reported in the text as "consistently 9.2"
Data from Butler and Hathaway, 2020, include average concentrations and standard deviations
Table 5-5: Minimum Average Influent Concentration Treated - Active Treatment
Constituent
Minimum
Average
Influent
Concentration
Average Effluent
Concentration
Mine / Mode
Source
Concentrations reported as dissolved in mg/L
Aluminum
16.08
0.5
Britannia
Madsen et al., 2012
Arsenic
2.239
0.00859
Leviathan/Dual-stage
U.S. EPA, 2006a
Cadmium
0.0261
ND
Leviathan/Single-stage
U.S. EPA, 2006a
Chromium
0.341
0.00304
Leviathan/Single-stage
U.S. EPA, 2006a
Copper
0.502
0.00307
Leviathan/Single-stage
U.S. EPA, 2006a
Iron
0.66
0.01
Britannia
Madsen et al., 2012
Lead
0.0071
0.00156
Leviathan/Single-stage
U.S. EPA, 2006a
Manganese
3.45
0.3
Britannia
Madsen et al., 2012
Nickel
2.56
0.0468
Leviathan/Single-stage
U.S. EPA, 2006a
Selenium
0.0088
0.00378
Leviathan/Dual-stage
U.S. EPA, 2006a
Zinc
0.538
0.00561
Leviathan/Single-stage
U.S. EPA, 2006a
5-6
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Neutralization and Chemical Precipitation
Table 5-5: Minimum Average Influent Concentration Treated - Active Treatment
Constituent
Minimum
Average
Influent
Concentration
Average Effluent
Concentration
Mine / Mode
Source
Concentrations reported as dissolved in mg/L
PH
4.2
9.2a
Britannia
Madsen et al., 2012
Notes:
ND = Not detected, detection limit not reported
a = The average effluent pH was reported in the text as "consistently 9.2"
Table 5-6: Maximum Average Effluent Concentration Attained - Active Treatment
Constituent
Maximum
Average
Effluent
Concentration
Average
Influent
Concentration
Mine / Mode
Source
Concentrations reported in mg/L and as dissolvec
standard units
, except iron that is reported as total; pH reported in
Aluminum
1.118
381
Leviathan/Dual-stage
U.S. EPA, 2006a
Arsenic
0.00859
2.239
Leviathan/Dual-stage
U.S. EPA, 2006a
Cadmium
0.002
0.087
Britannia
Madsen et al., 2012
Chromium
0.0057
0.877
Leviathan/Dual-stage
U.S. EPA, 2006a
Copper
0.02
13.9
Britannia
Madsen et al., 2012
Iron
12.28 ± 12.74
199.15 ±64.75
Elizabeth Mine
Butler and
Hathaway, 2020
Lead
0.002
0.0082
Leviathan/Dual-stage
U.S. EPA, 2006a
Manganese
0.4
3.94/4. la
Britannia
Madsen et al., 2012
Nickel
0.0468
2.56
Leviathan/Single-stage
U.S. EPA, 2006a
Selenium
0.00378
0.0088
Leviathan/Dual-stage
U.S. EPA, 2006a
Zinc
0.04
14.8
Britannia
Madsen et al., 2012
PH
9.2b
3.7 - 4.2b
Britannia
Madsen et al., 2012
Notes:
a = The average annual effluent reported was 0.4 in two different years; the average annual influent
concentrations are provided for both years
b = The average effluent pH was reported in the text as "consistently 9.2"; the range in average influent
pH is provided
Data from Butler and Hathaway, 2020, include average concentrations and standard deviations
5-7
-------
Neutralization and Chemical Precipitation
Table 5-7: Minimum Average Effluent Concentration Attained - Active Treatment
Constituent
Minimum
Average
Effluent
Concentration
Average
Influent
Concentration
Mine / Mode
Source
Concentrations reported as dissolved in mg/L; pH reported in standard units
Aluminum
0.4
19.3
Britannia
Madsen et al.,
2012
Arsenic
0.0063
3.236
Leviathan/Single-stage
U.S. EPA, 2006a
Cadmium
ND
0.0261
Leviathan/Single-stage
U.S. EPA, 2006a
Chromium
0.00304
0.341
Leviathan/Single-stage
U.S. EPA, 2006a
Copper
0.00307
0.502
Leviathan/Single-stage
U.S. EPA, 2006a
Iron
<0.01
0.95
Britannia
Madsen et al.,
2012
Lead
0.00156
0.0071
Leviathan/Single-stage
U.S. EPA, 2006a
Manganese
0.1
4.33
Britannia
Madsen et al.,
2012
Nickel
0.0342
7.024
Leviathan/Dual-stage
U.S. EPA, 2006a
Selenium
0.00214
0.0271
Leviathan/Single-stage
U.S. EPA, 2006a
Zinc
0.00561
0.538
Leviathan/Single-stage
U.S. EPA, 2006a
PH
9.2a
3.7 - 4.2a
Britannia
Madsen et al.,
2012
Notes:
ND = Not detected, detection limit not reported
a = The average effluent pH was reported in the text as "consistently 9.2"; the range in average
influent pH is provided
Lime treatment can treat both the highest and lowest average influent concentrations of all elements
presented, as shown by comparison of Tables 5-4 and 5-5 with Table 5-6, indicating maximum average
effluent concentrations are lower than both maximum and minimum influent concentrations. On
average, concentrations are decreased by one to three orders of magnitude relative to maximum and
minimum influent concentrations. In the case of lead, maximum and minimum average influent
concentrations and maximum and minimum average effluent concentrations are on the same order of
magnitude, which is true also for the minimum average influent of selenium. Therefore, treatment
appears less efficient, on average, but this likely is because concentrations already are low (in the <10
Hg/I range). Lead sulfate is insoluble except at very low or very high pH; therefore, in MIW having high
concentrations of sulfate, dissolved lead concentrations would be expected to be low. The minimum
average influent selenium concentration is an order of magnitude lower than the maximum average
influent concentration, but both the minimum and maximum average effluent concentrations are on the
same order of magnitude. This suggests that, on average, there is a minimum concentration (~0.002
mg/L) to which selenium can be treated passively with lime. As shown in Table 5-7, lime treatment can
reduce cadmium and iron concentrations to below their detection limits. On average, all elements but
5-8
-------
Neutralization and Chemical Precipitation
aluminum, manganese and nickel can be treated to concentrations <0.01 mg/L, whereas those are able
to be reduced to <0.4 mg/L. Lime treatment also increases pH.
5.4.3 Average Mass Removed
This chapter includes a single case study that provided yearly influent volumes treated, as well as
average influent and effluent concentrations (Madsen et al., 2012). Yearly average mass treated and
removed for each of the constituents were calculated from the data provided in the case study. The
calculated mass treated and removed for each contaminant is presented in Table C-3 in Appendix C.
Over the entire study, 2006-2010, thousands to hundreds of thousands of kilograms (kg) of total metals
were removed by the lime treatment system. Zinc had the highest initial mass at about 103,700 kg and
103,550 kg of zinc were removed. Cadmium had the lowest initial mass at 293 kg and 289 kg were
removed.
5.4.4 Removal Efficiency
The maximum and minimum average removal efficiencies in Table 5-8 and Table 5-9, respectively, were
determined by a review of data in Appendix C, Table C-4.
Table 5-8: Maximum Removal Efficiencies-Active Treatment
Constituent
Maximum
Removal
Efficiency
Mine / Mode
Source
All constituents reported as dissolved
Aluminum
99.9%
Leviathan/Dual-stage
U.S. EPA, 2006a
Arsenic
99.9%
Leviathan/Single-stage
U.S. EPA, 2006a
Cadmium
99.7%
Leviathan/Single-stage
U.S. EPA, 2006a
Chromium
99.9%
Leviathan/Dual-stage
U.S. EPA, 2006a
Copper
100.0%
Britannia3
Madsen et al., 2012
Iron
100.0%
Leviathan/Single-stage and
Dual-stage
U.S. EPA, 2006a
Lead
89.8%
Leviathan/Single-stage
U.S. EPA, 2006a
Manganese
97.7%
Britannia3
Madsen et al., 2012
Nickel
99.9%
Leviathan/Dual-stage
U.S. EPA, 2006a
Selenium
94.4%
Leviathan/Single-stage
U.S. EPA, 2006a
Zinc
99.9%
Britannia3
Madsen et al., 2012
Notes:
a = EPA calculated removal efficiencies from the average influent and effluent
concentrations for each year (2006 to 2010)
5-9
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Neutralization and Chemical Precipitation
Table 5-9: Minimum Removal Efficiencies-Active Treatment
Constituent
Minimum
Removal
Efficiency
Mine/Mode
Source
All constituents reported as dissolved
Aluminum
96.90%
Britannia3
Madsen et al., 2012
Arsenic
99.20%
Leviathan/Dual-stage
U.S. EPA, 2006a
Cadmium
97.50%
Leviathan/Dual-stage
U.S. EPA, 2006a
Chromium
93.80%
Leviathan/Dual-stage
U.S. EPA, 2006a
Copper
99%
Leviathan/Single-stage
U.S. EPA, 2006a
Iron
93.40%
Britannia3
Madsen et al., 2012
Lead
48.30%
Leviathan/Single-stage
U.S. EPA, 2006a
Manganese
89.80%
Britannia3
Madsen et al., 2012
Nickel
95.70%
Leviathan/Single-stage
U.S. EPA, 2006a
Selenium
91%
Leviathan/Single-stage
U.S. EPA, 2006a
Zinc
97.40%
Leviathan/Dual-stage
U.S. EPA, 2006a
Notes:
a = EPA calculated removal efficiencies from the average influent and effluent
concentrations for each year (2006 to 2010)
As shown in Table 5-8, the maximum removal efficiencies for active lime treatment ranged from about
90 percent (lead) to 100 percent (copper and iron) in the studies examined. The minimum removal
efficiencies ranged from 48 percent (lead) to 99 percent (arsenic and copper) (Table 5-9). With the
exceptions of lead and manganese, lime treatment has a minimum removal efficiency of greater than 90
percent for all elements in Table 5-9.
5.4.5 Flow Rates
Flow rates for the three studies are provided in Table 5-10.
Table 5-10: Flow Rate - Active Treatment
Maximum
Minimum
Average Influent
Mine / Mode
Source
Influent Flow
Influent Flow
Flow Rate
Rate
Rate
All rates are in liters per minute (L/min)
246
212
223
Leviathan/Single-stage
U.S. EPA, 2006a
662
587
640
Leviathan/Dual-stage
U.S. EPA, 2006a
193.19
100.64
140.34 ± 16.83
Elizabeth Mine (2009)
Butler and
Hathaway, 2020
166.13
92.81
122.67 ± 20.67
Elizabeth Mine (2010)
Butler and
Hathaway, 2020
218
34
100.00 ± 27.33
Elizabeth Mine (2011)
Butler and
Hathaway, 2020
102.23
59.25
85.34 ± 13.17
Elizabeth Mine (2012)
Butler and
Hathaway, 2020
5-10
-------
Neutralization and Chemical Precipitation
Table 5-10: Flow Rate - Active Treatment
Maximum
Minimum
Average Influent
Mine / Mode
Source
Influent Flow
Influent Flow
Flow Rate
Rate
Rate
117.38
70.35
85.00 ±8.50
Elizabeth Mine (2013)
Butler and
Hathaway, 2020
86.78
63.86
73.17 ±5.67
Elizabeth Mine (2014)
Butler and
Hathaway, 2020
87.41
51.19
65.50 ±7.17
Elizabeth Mine (2015)
Butler and
Hathaway, 2020
96
46.09
76.33 ± 10.00
Elizabeth Mine (2016)
Butler and
Hathaway, 2020
114.45
62.14
89.50 ±9.50
Elizabeth Mine (2017)
Butler and
Hathaway, 2020
NS
NS
7,435
Britannia3 (2006)
Madsen et al.,
2012
NS
NS
10,005
Britannia3 (2007)
Madsen et al.,
2012
NS
NS
7,298
Britannia3 (2008)
Madsen et al.,
2012
NS
NS
6,412
Britannia3 (2009)
Madsen et al.,
2012
NS
NS
8,423
Britannia3 (2010)
Madsen et al.,
2012
NS
NS
7,915b
Britannia3 Overall
Madsen et al.,
2012
Notes:
NS = Not stated
a = EPA calculated the average flow rate from annual flows presented in Table 4 for 2006-2010
b = Average treatment plant flow rate (2006-2010)
Data from Butler and Hathaway (2020) include average flow rates and standard deviations by year
As shown in Table 5-10, active neutralization and chemical precipitation can treat a wide variety of
flows, with average flow rates treated being greater than 10,000 liters per minute (L/min) and a
minimum flow as low as 34 L/min.
5.5 Capability - Semi-Passive Treatment
The inclusion of only one case study (U.S. EPA, 2006a) that met the criteria (see Section 1.1.1) for this
work limits the ability to determine the capability of semi-passive lime treatment, in general. In the
single case study evaluated, the treatment system relied on mechanical aeration and lime dosing prior
to gravity flow to alkaline treatment lagoons (U.S. EPA, 2006a). Nevertheless, the following sections
present capability data for the technology based on the single study.
5-11
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Neutralization and Chemical Precipitation
5.5.1 Ranges of Applicability
Tables 5-11 and 5-12, respectively, show the range of concentrations (maximum influent and
corresponding effluent; and minimum influent and corresponding effluent) treated semi-passively with
lime from Appendix C, Table C-l in the single case study (U.S. EPA, 2006a).
Table 5-11: Maximum Influent and Corresponding Effluent Concentrations-Semi-PassiveTreatment
Constituent
Maximum
Influent
Concentration
Corresponding
Effluent
Concentration
Mine / Mode
Source
Concentrations reported as disso
ved in mg/L; pH reported in standard units
Aluminum
33.6
0.254
Leviathan/Alkal
ne Lagoon
U.S. EPA, 2006a
Arsenic
0.545
0.0129
Leviathan/Alkal
ne Lagoon
U.S. EPA, 2006a
Chromium
0.0235
0.0038
Leviathan/Alkal
ne Lagoon
U.S. EPA, 2006a
Copper
0.0163
0.0061
Leviathan/Alkal
ne Lagoon
U.S. EPA, 2006a
Iron
460
0.0172
Leviathan/Alkal
ne Lagoon
U.S. EPA, 2006a
Lead
0.0063
0.0026
Leviathan/Alkal
ne Lagoon
U.S. EPA, 2006a
Nickel
1.69
0.0472
Leviathan/Alkal
ne Lagoon
U.S. EPA, 2006a
Selenium
0.007
<0.0025
Leviathan/Alkal
ne Lagoon
U.S. EPA, 2006a
Zinc
0.369
0.019
Leviathan/Alkal
ne Lagoon
U.S. EPA, 2006a
PH
4.59
7.92
Leviathan/Alkal
ne Lagoon
U.S. EPA, 2006a
Notes:
< = Not detected above laboratory method detection limit shown
Table 5-12: Minimum Influent and Corresponding Effluent Concentrations - Semi-Passive Treatment
Constituent
Minimum
Influent
Concentration
Corresponding
Effluent
Concentration
Mine / Mode
Source
Concentrations reported as dissolved in mg/L; pH reported in standard units
Aluminum
30.9
0.185
Leviathan/Alkaline Lagoon
U.S. EPA, 2006a
Arsenic
0.485
0.0038
Leviathan/Alkaline Lagoon
U.S. EPA, 2006a
Chromium
0.0162
0.0014
Leviathan/Alkaline Lagoon
U.S. EPA, 2006a
Copper
0.0092
0.0031
Leviathan/Alkaline Lagoon
U.S. EPA, 2006a
Iron
360
0.0881
Leviathan/Alkaline Lagoon
U.S. EPA, 2006a
Lead
0.0027
<0.0012
Leviathan/Alkaline Lagoon
U.S. EPA, 2006a
Nickel
1.57
0.0201
Leviathan/Alkaline Lagoon
U.S. EPA, 2006a
Selenium
0.0022a
0.0036
Leviathan/Alkaline Lagoon
U.S. EPA, 2006a
Zinc
0.35
0.0062
Leviathan/Alkaline Lagoon
U.S. EPA, 2006a
PH
4.59
7.92
Leviathan/Alkaline Lagoon
U.S. EPA, 2006a
Notes:
< = Not detected above laboratory method detection limit shown
a = Value reported in reference, but is below the reference's reported detection limit
5-12
-------
Neutralization and Chemical Precipitation
As shown in Table 5-11 and Table 5-12, aluminum, arsenic, chromium, copper, iron, lead, nickel,
selenium and zinc are all treatable to concentrations below about 0.2 mg/L by lime in a semi-passively
operated system (U.S. EPA, 2006a). Lead shows the least change between minimum and maximum
influent concentrations and corresponding effluent concentrations, owing to low influent
concentrations being treated, but was decreased by more than 50 percent. Minimum and maximum
influent selenium concentrations and their corresponding effluent concentrations are all close to the
detection limit and therefore may or may not represent treatability.
5.5.2 Average Influent and Effluent Concentrations
Data provided were insufficient to determine the maximum and minimum average influents treated and
the maximum and minimum effluents attained. Therefore, Table 5-13 lists only the average influent
concentrations and average effluent concentrations reported for aluminum, arsenic, cadmium,
chromium, copper, iron, nickel, selenium and zinc from Appendix C, Table C-2.
Table 5-13: Average Influent Concentration Treated - Semi-Passive Treatment
Constituent
Average
Influent
Concentration
Average
Effluent
Concentration
Mine / Mode
Source
Concentrations reported as dissolved in mg/L; pH reported in standard units
Aluminum
31.988
0.251
Leviathan/Alkaline Lagoon
U.S. EPA, 2006a
Arsenic
0.519
0.00584
Leviathan/Alkaline Lagoon
U.S. EPA, 2006a
Cadmium
ND
0.00038
Leviathan/Alkaline Lagoon
U.S. EPA, 2006a
Chromium
0.0193
0.00225
Leviathan/Alkaline Lagoon
U.S. EPA, 2006a
Copper
0.0135
0.00546
Leviathan/Alkaline Lagoon
U.S. EPA, 2006a
Iron
391.25
0.148
Leviathan/Alkaline Lagoon
U.S. EPA, 2006a
Lead
0.0051
0.00166
Leviathan/Alkaline Lagoon
U.S. EPA, 2006a
Nickel
1.631
0.0226
Leviathan/Alkaline Lagoon
U.S. EPA, 2006a
Selenium
0.0033
0.00324
Leviathan/Alkaline Lagoon
U.S. EPA, 2006a
Zinc
0.356
0.0142
Leviathan/Alkaline Lagoon
U.S. EPA, 2006a
Notes:
ND = Not detected, detection limit not provided
Although the average influent concentrations are not directly comparable to the average effluent
concentrations (i.e., a concentration equal to the average influent concentration may or may not be
treated to the average concentration reported for the effluent), the average effluent concentrations
lower than the average influent concentrations shown in Table 5-13 indicates these constituents are
successfully treatable in a semi-passive system. The one exception is cadmium, where the influent
concentrations on all sampling dates were below detection; therefore, no assessment can be made as to
whether cadmium is treatable via this method without inclusion of additional studies. Lead and
selenium average influent concentrations were less than about 0.005 mg/L, as were average effluent
concentrations. On average, lead appears to be able to be decreased further in concentration from a
low value, but selenium appears to be untreatable at average concentrations to lower than about
0.0033 mg/L by semi-passive lime treatment.
5-13
-------
Neutralization and Chemical Precipitation
5.5.3 Removal Efficiency
The maximum and minimum removal efficiencies are provided in Table 5-14, from Appendix C, Table C-
4.
Table 5-14: Removal Efficiencies - Semi-Passive Treatment
Constituent
Maximum
Removal
Efficiency
Minimum
Removal
Efficiency
Mine
Source
All constituents reported as dissolved
Aluminum
99.5%
98%
Leviathan Mine / Alkaline Lagoon
U.S. EPA, 2006a
Arsenic
99.5%
97.6%
Leviathan Mine / Alkaline Lagoon
U.S. EPA, 2006a
Chromium
92.3%
83.1%
Leviathan Mine / Alkaline Lagoon
U.S. EPA, 2006a
Copper
74.5%
27.7%
Leviathan Mine / Alkaline Lagoon
U.S. EPA, 2006a
Iron
100%
99.9%
Leviathan Mine / Alkaline Lagoon
U.S. EPA, 2006a
Lead
78.9%
37.7%
Leviathan Mine / Alkaline Lagoon
U.S. EPA, 2006a
Nickel
99.1%
97.2%
Leviathan Mine / Alkaline Lagoon
U.S. EPA, 2006a
Zinc
98.2%
90.6%
Leviathan Mine / Alkaline Lagoon
U.S. EPA, 2006a
As shown in Table 5-14, semi-passive lime treatment in a lagoon has maximum removal efficiencies of
over 90 percent for aluminum, arsenic, iron, nickel, chromium and zinc. Maximum removal efficiencies
for copper and lead are lower, at 74.5 percent and 78.9 percent, respectively. The range of removal
efficiencies is narrow for most elements in Table 5-14, but the technology is more variable for copper
and lead, with ranges in removal efficiencies of 27.7 to 74.5 percent for copper and 37.7 to 78.9 percent
for lead.
5.5.4 Flow Rates
U.S. EPA (2006a) reported that the semi-passive lime treatment system at Leviathan Mine treated flows
between 62 to 120 L/min.
5.6 Capability - Passive Treatment
Because only a single case study was evaluated that met this study's criteria, it is not possible to provide
evaluation on a technology-wide basis.
5.6.1 Ranges of Applicability
No non-averaged corresponding influent and effluent concentrations of constituents treated were
presented in the single case study; therefore, the range of applicability cannot be determined.
5.6.2 Average Influent and Effluent Concentrations
Because the study presented average concentrations of constituents over the entire sampling period of
six months, highest and lowest average influent concentrations and highest and lowest effluent
concentrations cannot be determined. Table 5-15 presents the average influent and effluent
concentrations from the two limestone-DAS tanks.
5-14
-------
Neutralization and Chemical Precipitation
Table 5-15: Average Influent and Effluent Concentrations - Tanks 1 and 2
Constituent
Average
Influent
Concentration
Average
Effluent
Concentration
Mine
Source
Notes
Concentrations reported as dissolved in mg/L; pH reported in standard units
Aluminum
100
10
Monte Romero
Macfas et al., 2012a
Tank 1
Aluminum
10
<0.2
Monte Romero
Macfas et al., 2012a
Tank 2
Arsenic
97
<0.002
Monte Romero
Macfas et al., 2012a
Tank 1
Arsenic
<0.002
<0.002
Monte Romero
Macfas et al., 2012a
Tank 2
Calcium
252
810
Monte Romero
Macfas et al., 2012a
Tank 1
Calcium
790
850
Monte Romero
Macfas et al., 2012a
Tank 2
Copper
5
<0.005
Monte Romero
Macfas et al., 2012a
Tank 1
Copper
<0.005
<0.005
Monte Romero
Macfas et al., 2012a
Tank 2
Iron
171
15
Monte Romero
Macfas et al., 2012a
Tank 1
Iron
5
<0.2
Monte Romero
Macfas et al., 2012a
Tank 2
Lead
182
<0.001
Monte Romero
Macfas et al., 2012a
Tank 1
Lead
<0.001
<0.001
Monte Romero
Macfas et al., 2012a
Tank 2
Magnesium
263
279
Monte Romero
Macfas et al., 2012a
Tank 1
Magnesium
316
386
Monte Romero
Macfas et al., 2012a
Tank 2
Manganese
18
19
Monte Romero
Macfas et al., 2012a
Tank 1
Manganese
18
19
Monte Romero
Macfas et al., 2012a
Tank 2
Potassium
3
4
Monte Romero
Macfas et al., 2012a
Tank 1
Potassium
7
7
Monte Romero
Macfas et al., 2012a
Tank 2
Silicon
38
19
Monte Romero
Macfas et al., 2012a
Tank 1
Silicon
18
11
Monte Romero
Macfas et al., 2012a
Tank 2
Sulfate
3440
3590
Monte Romero
Macfas et al., 2012a
Tank 1
Sulfate
3870
3770
Monte Romero
Macfas et al., 2012a
Tank 2
Zinc
443
436
Monte Romero
Macfas et al., 2012a
Tank 1
Zinc
430
414
Monte Romero
Macfas et al., 2012a
Tank 2
PH
2.7
6.1
Monte Romero
Macfas et al., 2012a
Tank 1
PH
6
6.6
Monte Romero
Macfas et al., 2012a
Tank 2
Notes:
< = Not detected above laboratory method detection limit given
Average influent and effluent obtained from Table 1 of Macfas et al., 2012a, where NFOL represents
Tank 1 influent and influent for Tank 2 is represented by D2 out (second decant pond in reference
Figure 1)
Although the average influent and average effluent values are not directly related, data in Table 5-15
indicate that limestone-DAS is able to decrease average concentrations of copper, arsenic and lead to
below their detection limits. On average, high concentrations of aluminum and iron can be treated with
average effluent concentrations being an order of magnitude lower than average influent
concentrations and pH can be increased from acidic to near neutral. Average influent concentrations of
5-15
-------
Neutralization and Chemical Precipitation
manganese and zinc were similar to average effluent concentrations, indicating that they are not able to
be treated with limestone-DAS.
5.6.3 Removal Efficiency
Average removal efficiencies for each limestone-DAS tank are provided in Table 5-16.
Table 5-16: Removal Efficiencies - Tanks 1 and 2
Constituent
Tank 1 Average
Removal
Efficiency
Tank 2 Average
Removal
Efficiency
Source
All constituents reported as dissolved
Aluminum
90%
99%
Macfas et al., 2012a
Arsenic
100%
NA
Macfas et al., 2012a
Calcium
-221%
-8%
Macfas et al., 2012a
Copper
100%
NA
Macfas et al., 2012a
Iron
91%
98%
Macfas et al., 2012a
Lead
100%
NA
Macfas et al., 2012a
Magnesium
-6%
-22%
Macfas et al., 2012a
Manganese
-6%
-6%
Macfas et al., 2012a
Potassium
-33%
0%
Macfas et al., 2012a
Silicon
50%
39%
Macfas et al., 2012a
Sulfate
-4%
3%
Macfas et al., 2012a
Zinc
2%
4%
Macfas et al., 2012a
Notes:
NA = not applicable, because effluent concentration from Tank 1 (and influent to Tank 2) was
below detection
EPA calculated removal efficiency based on data in Table 1 of the reference
For non-detect results, EPA used Vz the detection limit for calculations
On average, arsenic, copper and lead were removed to below their detection limits by the first
limestone-DAS unit without need for aeration or the second DAS unit. Aluminum and iron also were able
to be treated to below their detection limits, but not by a single pass through the limestone-DAS unit.
Therefore, it appears the limestone-DAS technology is effective for aluminum and iron, but that greater
than 90 mg/L aluminum or greater than about 150 mg/L iron the water may require an additional pass
through a limestone-DAS. The average pH achieved is typical of limestone-based treatments where
carbon dioxide is in equilibrium with bicarbonate. Manganese and zinc were not treatable by the
limestone-DAS technology, which most likely is because pH is not increased sufficiently to facilitate
precipitation of the ions as either carbonates or hydroxides.
5.6.4 Flow Rates
The flow rate for the technology is set to meet the residence time desired. In the single case study
evaluated, the flow was set to 1 L/min to obtain a residence time of 24 hours for Tanks 1 and 2 and 4
days for each settling pond (Macfas et al., 2012a).
5-16
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Neutralization and Chemical Precipitation
5.7 Costs
The costs for an active lime treatment system vary from about $200,000 to $1,480,000 per year (U.S.
EPA, 2006a; Madsen, 2012; Butler and Hathaway, 2020). U.S. EPA (2006a) found that operating in a two-
stage system, to first remove arsenic and then to remove remaining constituents, resulted in reduced
materials handling and sludge disposal costs due to arsenic being concentrated in a smaller volume of
sludge requiring disposal as a hazardous waste. Based on a single study (U.S. EPA, 2006a), costs
approach $470,000 for construction and first year operation of a semi-passive lime treatment system,
with nearly $280,000 of the total for site preparation, capital and equipment. First year costs for the
semi-passive system were approximately $40 per 1,000 liters; first year costs for active lime treatment
were between $112 and $128 per 1,000 liters (U.S. EPA, 2006a). Costs were not provided in the single
passive treatment case study evaluated.
As additional case studies meeting the project's criteria are identified, future comparisons may provide
additional information on treatment costs.
5.8 Lessons Learned
• Major performance issues (and increased maintenance costs) arise from gypsum scale and lime
feed and delivery issues that cause plugging of pumps, outlets from holding and reaction tanks,
monitoring probes, and pipes. Potential remedies are the use of a higher purity lime, mechanical
mixing, or better pumping systems (U.S. EPA, 2006a; Butler and Hathaway, 2020).
• Cold weather operation may be hindered by icing of the fabric of bag filters that creates
backpressure (U.S. EPA, 2006a).
• The pre-existing iron terraces, cascades, and lagoon (the NFOL) aided in efficiency of iron and
aluminum removal by the limestone DAS (Macfas et al., 2012a).
• System design should consider ease of access for maintenance, potential for upgrades and use
of universal motors (Butler and Hathaway, 2020).
5.9 References
5.9.1 Case Study References
Butler, B.A. and E. Hathaway. 2020. Evaluation of the Rotating Cylinder System™ at Elizabeth Mine,
Vermont. US Environmental Protection Agency (U.S. EPA), Land Remediation and Technology Division
Center for Environmental Solutions and Emergency Response. (EPA/600/R-19/194). 42 pp.
Macfas, F., Caraballo, M.A., Nieto, J.M., Rotting, T.S., and Ayora, C. 2012a. Natural pretreatment and
passive remediation of highly polluted acid mine drainage. Journal of Environmental Management,
104:93-100.
Macfas, F., Caraballo, M.A., Rotting, T.S., Perez-Lopez, R., Nieto, J.M., and Ayora, C. 2012b. From highly
polluted Zn-rich acid mine drainage to non-metallic waters: Implementation of a multi-step alkaline
passive treatment system to remediate metal pollution. Science of the Total Environment, 433:323-330.
Madsen, C., O'Hara, G., and Sinnet, G. 2012. "Management of Acid Rock Drainage at Britannia Mine, BC,
Part 2: Water Treatment Plant Implementation and Operations." In Proceedings from the 9th
International Conference on Acid Rock Drainage (ICARD), Volume 1 of 2, Ottawa, Canada, May 20-26,
2012. pp. 295-306. Eds. Price, W.A., Hogan, C., and Tremblay.
5-17
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Neutralization and Chemical Precipitation
Rotting, T.S., Caraballo, M.A., Serrano, J.A., Ayora, C., and Carrera, J. 2008a. Field application of calcite
Dispersed Alkaline Substrate (calcite-DAS) for passive treatment of acid mine drainage with high Al and
metal concentrations. Applied Geochemistry, 23(6):1660-1674.
Rotting, T.S., Thomas, R.C., Ayora, C., and Carrera, J. 2008b. Passive treatment of acid mine drainage
with high metal concentrations using Dispersed Alkaline Substrate. Journal of Environmental Quality,
37:1741-1751.
U.S. Environmental Protection Agency (U.S. EPA). 2006a. Active and Semi-Passive Lime Treatment of Acid
Mine Drainage at Leviathan Mine, Innovative Technology Evaluation Report. (EPA/540/R-05/015). 92 pp.
5.9.2 General Neutralization Chemical Precipitation Treatment References
Kratochvil, D., Ye, S., and Lopez, O. 2015. "Commercial Case Studies of Life Cycle Cost Reduction of ARD
Treatment with Sulfide Precipitation." Paper presented at 10th International Conference on Acid Rock
Drainage and IMWA Annual Conference, Santiago, Chile, April 21-24, 2015. 11 pp.
5-18
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Chemical Stabilization
6 Chemical Stabilization
Chemical stabilization technologies use a variety of amendments to reduce the mobility of metals in
solid mining wastes, which limits the formation of metal-contaminated leachate or runoff. Alkaline
materials, such as limestone, are common amendments that neutralize acidity produced by the
oxidation of sulfide minerals in mining wastes. Phosphate, silicate or other coating materials can be
applied to the surfaces of mining wastes to prevent oxidation of sulfidic minerals in the wastes through
isolation (Trudnowski, 2004; Nordwicket al, 2006). Isolation includes passivation and
microencapsulation.
Solid mine wastes can be treated either in situ or ex situ, with ex situ typically being associated with
removal of the mining wastes to an off-site repository (Interstate Technology and Regulatory Council
[ITRC], 2010). In theory, some types of chemical stabilization technologies that immobilize sulfide or
metals or create a barrier to leaching should last indefinitely; therefore, only one application of the
treatment would be needed to permanently stabilize the mining waste (Trudnowski, 2004; Nordwick et
al., 2006).
6.1 Case Studies Evaluated
This chapter provides an evaluation of one case study where chemical stabilization was the primary
component of treatment. The case study was selected based on the screening criteria presented in
Section 1.1.1 and examined four types of chemical stabilization technologies applied to waste rock at a
site in South Dakota. An additional case study meeting the selection criteria was identified, but data
were unavailable at the time of this report compilation. Table 6-1 summarizes the site name and
location, design information, and reference for the case study. The chapter provides considerations for
constraints, treatability of contaminants, capability, technological and site-specific requirements and
lessons learned for chemical stabilization treatment from evaluation of the case study results.
Table 6-1: Chemical Stabilization Case Study Site
Site
Type
System Description
Study
Reference
Reference
Name
Type
Type
and
Location
Gilt
Envirobond (Metals Treatment
Applied as a liquid
Pilot
Trudnowski,
Report
Edge
Technologies, MT2)a
spray onto waste
scale
2004*
Mine,
rock in two above-
South
ground treatment
Nordwick et
Dakota
cells; used
phosphate
stabilization
chemistry
al., 2006
6-1
-------
Chemical Stabilization
Table 6-1: Chemical Stabilization Case Study Site
Site
Name
and
Location
Type
System Description
Study
Type
Reference
Reference
Type
Potassium Permanganate
Passivation Technology
(University of Nevada-Reno)
Applied in two
phases: 1) waste
rock, magnesium
oxide and calcium
oxide (lime) were
mixed ex situ, 2) a
mixture of water,
caustic soda and
potassium
permanganate were
applied to the waste
rock mixture in two
above-ground
treatment cells
Silica Microencapsulation
(SME) Technology (Klean Earth
Environmental Company,
KEECO)
Applied as a liquid
spray onto waste
rock in two above-
ground treatment
cells
Lime
Waste rock was
mixed with calcium
oxide ex situ and
placed into three
above-ground
treatment cells
Notes:
a = MT2's Envirobond product is no longer available. The current MT2 ECOBOND® brand supersedes
MT2 Envirobond (James M. Barthel, MT2 CEO, personal communication, 2020)
*Primary source(s) of data for evaluation in this chapter
6.2 Constraints
Constraints associated with some chemical stabilization technologies include high costs of large amounts
of the chemical reagents needed for successful treatment (Trudnowski, 2004). Effective mixing or
coating of reagents with waste materials is necessary.
6.3 Treatable Contaminants
MT2 Envirobond, potassium permanganate passivation, silica microencapsulation, and lime treatment
can lower concentrations of aluminum, arsenic, iron, sulfate, zinc and raise pH in leachate from treated
waste rock. Lime, potassium permanganate passivation, and silica encapsulation are also able to reduce
6-2
-------
Chemical Stabilization
concentrations of arsenic and sulfate. However, leachate from lime-treated mining wastes may require
further treatment to adjust pH to near neutral prior to it reaching a waterbody.
6.4 Capability
Evaluation of only one case study (Trudnowski, 2004) that met the criteria (see Section 1.1.1) for this
work limits the ability to determine the capability of the chemical stabilization technologies.
Nevertheless, the following sections present capability data for the four technologies used in the single
study.
6.4.1 Ranges of Applicability
The Gilt Edge Mine case study evaluated the four chemical stabilization treatment technologies against a
control (cells of waste rock with no treatment applied) over two years. Like the Caps and Covers chapter
(Section 4), the range of applicability differs in this section as compared to other technologies, because
results are not based on an influent treated and a corresponding effluent attained, but rather are based
on general differences between concentrations of constituents in waste rock leachate originating from
treated versus untreated cells. Table 6-2 provides the ranges in average (replicated samples)
concentrations of constituents in leachate from treated and untreated cells.
6-3
-------
Chemical Stabilization
Table 6-2: Average Leachate Concentration Ranges from Treated and Untreated Cells of Waste
Rock - All Treatment Types
Constituent
Concentration
Range-
Untreated
Cells3
Concentration
Range-
Treated Cells'5
Technology
Source
Notes
(location
within
source)
Concentrations reported as dissolved in mg/L; pH reported in standard units
Aluminum
198.545 -
2,796.667
0.22-0.422
Lime
Trudnowski,
2004
Table 4-2
0.005-0.264
MT2 Envirobond
Trudnowski,
2004
Table 5-2
0.011-0.326
Potassium
Permanganate
Passivation
Trudnowski,
2004
Table 6-2
0.401-398.0
SME
Trudnowski,
2004
Table 7-2
Arsenic
1.4223 -
123.8027
0.0238-
0.0481c
Lime
Trudnowski,
2004
Appendix A
8.4950-50.20
MT2 Envirobond
Trudnowski,
2004
Appendix A
0.0059c -
2.6148c
Potassium
Permanganate
Passivation
Trudnowski,
2004
Appendix A
0.0056c -
0.04979c
SME
Trudnowski,
2004
Appendix A
Iron
535.110-
21,204.900
0.008-0.397
Lime
Trudnowski,
2004
Table 4-3
0.008-0.145
MT2 Envirobond
Trudnowski,
2004
Table 5-3
0.017-0.739
Potassium
Permanganate
Passivation
Trudnowski,
2004
Table 6-3
0.178-528.0
SME
Trudnowski,
2004
Table 7-3
Sulfate
1,106-
72,667
204 -1,403
Lime
Trudnowski,
2004
Table 4-4
8,150-26,700
MT2 Envirobond
Trudnowski,
2004
Table 5-4
1,490-8,350
Potassium
Permanganate
Passivation
Trudnowski,
2004
Table 6-4d
1,834-7,100
SME
Trudnowski,
2004
Table 7-4
Zinc
11.45-71.93
0.0045c -
0.0437c
Lime
Trudnowski,
2004
Appendix A
6-4
-------
Chemical Stabilization
Table 6-2: Average Leachate Concentration Ranges from Treated and Untreated Cells of Waste
Rock - All Treatment Types
Constituent
Concentration
Range-
Untreated
Cells3
Concentration
Range-
Treated Cells'5
Technology
Source
Notes
(location
within
source)
Concentrations reported as dissolved in mg/L; pH reported in standard units
0.0028c-
0.4720c
MT2 Envirobond
Trudnowski,
2004
Appendix A
0.0211c-
0.1645
Potassium
Permanganate
Passivation
Trudnowski,
2004
Appendix A
0.3555c -
21.5333
SME
Trudnowski,
2004
Appendix A
pHe
2.49-4.52
6.85-12.09
Lime
Trudnowski,
2004
Appendix B
6.78-7.95
MT2 Envirobond
Trudnowski,
2004
Appendix B
7.15-8.55
Potassium
Permanganate
Passivation
Trudnowski,
2004
Appendix B
2.71-6.86
SME
Trudnowski,
2004
Appendix B
Notes:
Average concentrations were not reported for all sampling dates, or for all replicated samples for
some dates, due to lack of leachate volume for analysis. Therefore, maximum and minimum average
concentrations chosen for this table were obtained from comparison of sampling dates having
reported average concentrations based on at least two replicates in the reference tables indicated.
EPA calculated date-specific averages from replicated sample data provided in Appendices A and B
and data in this table were obtained from comparison of those results across the sampling dates.
RL = reporting limit (reference did not provide the value for the limit)
Date range = 2001-2002
a = The study included three untreated control cells
b = Lime treatment included three cells, whereas the other three treatments included two treatment
cells
c = Calculated from values provided in the reference where one or more values was noted as being
estimated
d = Reference table has incorrect units for sulfate in title
e = Average of the pH values provided by the source
6-5
-------
Chemical Stabilization
Lime, MT2 Envirobond and potassium permanganate passivation treatments all can reduce aluminum
and iron concentrations in leachate by three to five orders of magnitude, on average, with MT2
Envirobond appearing to be the most effective for minimizing the leachate concentration of aluminum.
Silica microencapsulation treatment appears less effective as compared to the other three technologies,
but the lower end of the range falls within, or close to, the ranges for the other technologies.
Lime, potassium permanganate passivation and silica microencapsulation treatments reduce average
arsenic concentrations in leachate by three to four orders of magnitude, as compared to leachate from
untreated waste rock. MT2 Envirobond can reduce average arsenic concentrations by two orders of
magnitude, but the range of concentrations in the leachate is higher than for the other technologies.
This could be due to changes in the waste rock over time, because concentrations of arsenic in leachate
from untreated waste rock was higher in some control units in 2002 versus in 2001 and lowest in MT2
Envirobond treated units in 2002 versus 2001 (Trudnowski, 2004). The lowest leachate concentrations
were achieved with potassium permanganate and silica microencapsulation treatments.
All four treatment technologies can decrease the amount of sulfate leached by one to two orders of
magnitude. Lime treatment is most effective at reducing concentrations of sulfate leached with the
highest concentration being lower than the lowest concentrations in the ranges for the other
treatments. MT2 Envirobond appears least effective.
Relative to control ranges in leachate concentrations, average zinc concentrations are decreased by two
to four orders of magnitude by lime treatment, MT2 Envirobond and potassium permanganate, with
average leachable amounts following lime treatment reduced to below the reporting limit, or near to it
(estimated data). Silica microencapsulation treatment appears minimally effective in attenuating
leaching of zinc, with differences between control and treatment upper range average leachate
concentrations on the same order of magnitude.
Relative to the range of average control leachate pH values (2.49-4.52), the range of average pH values
in leachate from all but the silica microencapsulation treated cells is higher (6.78 to 12.09). The highest
pH is attained by lime treatment, which is expected due to lime being a caustic material.
6.4.2 Average Leachate Concentrations from Untreated and Treated Cells of Waste Rock
Table 6-3 presents average leachate concentrations over all sampling dates and replicates from
untreated cells of waste rock and treated cells of waste rock for the four technologies.
6-6
-------
Chemical Stabilization
Table 6-3: Average Leachate Concentrations from Treated and Untreated Cells of Waste Rock - All
Treatment Types
Constituent
Average
Concentration
from
Untreated
Cells3
Average
Concentration
from Treated
Cells'5
Technology
Source
Notes
(location
within
source)
Concentrations reported as dissolved in mg/L; pH reported in standard units
Aluminum
687.800
0.1691
Lime
Trudnowski, 2004
Table 4-2
0.135
MT2 Envirobond
Trudnowski, 2004
Table 5-2
0.107
Potassium
Permanganate
Passivation
Trudnowski, 2004
Table 6-2
192.497
SME
Trudnowski, 2004
Table 7-2
Arsenicc
26.6829
0.0287
Lime
Trudnowski, 2004
Appendix A
36.8332
MT2 Envirobond
Trudnowski, 2004
Appendix A
0.2489
Potassium
Permanganate
Passivationd
Trudnowski, 2004
Appendix A
1.6265
SMEd
Trudnowski, 2004
Appendix A
Iron
4,237.946
0.0792
Lime
Trudnowski, 2004
Table 4-3
0.075
MT2 Envirobond
Trudnowski, 2004
Table 5-3
0.151
Potassium
Permanganate
Passivation
Trudnowski, 2004
Table 6-3
763.211
SME
Trudnowski, 2004
Table 7-3
Sulfate
22,406
444.3
Limed
Trudnowski, 2004
Table 4-4
18,425
MT2 Envirobond
Trudnowski, 2004
Table 5-4
2,443
Potassium
Permanganate
Passivation
Trudnowski, 2004
Table 6-4
6,026
SME
Trudnowski, 2004
Table 7-4
Zincc
36.3993
0.0329
Limed
Trudnowski, 2004
Appendix A
0.1398
MT2 Envirobondd
Trudnowski, 2004
Appendix A
0.0609
Potassium
Permanganate
Passivationd
Trudnowski, 2004
Appendix A
5.4349
SME
Trudnowski, 2004
Appendix A
pHe
3.52
10.56
Lime
Trudnowski, 2004
Appendix B
7.39
MT2 Envirobond
Trudnowski, 2004
Appendix B
6-7
-------
Chemical Stabilization
Table 6-3: Average Leachate Concentrations from Treated and Untreated Cells of Waste Rock - All
Treatment Types
Constituent
Average
Concentration
from
Untreated
Cells3
Average
Concentration
from Treated
Cells'5
Technology
Source
Notes
(location
within
source)
Concentrations reported as dissolved in mg/L; pH reported in standard units
7.18
Potassium
Permanganate
Passivation
Trudnowski, 2004
Appendix B
5.32
SME
Trudnowski, 2004
Appendix B
Notes:
Calculated from averages provided for all individual sampling dates in the tables indicated in the Notes
column, or from those that EPA calculated from data in the appendices indicated in the Notes column.
Date range = 2001-2002
a = The study included three control cells
b = Lime treatment included three cells, while the other three treatments included two treatment cells
c = Values calculated from all data provided by the source, including for sampling dates having results
reported as estimated or below the reporting limit
d = Majority of data provided by the source was indicated as estimated or below the reporting limit
e = Average of the pH values provided by the source
Lime, MT2 Envirobond and potassium permanganate passivation treatments reduce average aluminum
and iron concentrations over two years in leachate from treated waste rock by three to five orders of
magnitude, relative to leachate from untreated waste rock. Silica microencapsulation technology
reduces average aluminum and iron concentrations in treated leachate to a lesser degree, with average
aluminum concentration being on the same order of magnitude as in the leachate from untreated waste
rock and iron concentrations being decreased by only one order of magnitude.
Lime, potassium permanganate passivation and silica microencapsulation technologies reduce average
arsenic concentrations in leachate from treated waste rock by one to three orders of magnitude, relative
to leachate from untreated waste rock, with most samples contributing to the averages for potassium
permanganate and silica microencapsulation being below or near the reporting limit. Average arsenic
concentration in leachate from the MT2 Envirobond-treated rock over the two years was increased
relative to leachate from the untreated control, suggesting ineffective treatment. However, average
concentrations across individual dates in 2002 were an order of magnitude lower than those in 2001,
suggesting that MT2 Envirobond may be a source of arsenic (Trudnowski, 2004). Average arsenic
concentration in leachate from waste rock treated with the silica microencapsulation technology was
increased in 2002 versus 2001.
All four technologies decreased average sulfate concentrations leached. Lime treatment provided the
greatest decrease (two orders of magnitude). MT2 Envirobond treatment resulted in the smallest
average decrease in sulfate concentrations leached.
6-8
-------
Chemical Stabilization
Lime, MT2 Envirobond and potassium permanganate passivation reduced average zinc concentrations in
leachate from treated waste rock by two to three orders of magnitude; silica microencapsulation
treatment reduces average zinc concentrations by an order of magnitude. Similar to arsenic, average
concentrations of zinc in leachate from waste rock treated with silica microencapsulation were higher in
2002 than in 2001.
All four treatments provided increased pH (averaged over the two years) as compared to the pH of
leachate from untreated waste rock. The average pH in leachate from lime treatment was basic (pH
10.5), whereas it was neutral (7.39 and 7.18) in leachate from waste rock treated with MT2 Envirobond
and potassium permanganate, respectively. The average pH over the two years in leachate from the
silica microencapsulation treatment was slightly acidic at pH 5.32; however, the average over the first
year was near neutral at 6.51 and the second year was acidic at 2.55. The lower average pH corresponds
with the higher average concentrations of arsenic and zinc in leachate from silica encapsulation treated
waste rock.
6.4.3 Percent Reduction
Table 6-4 presents percentage reductions in leachate concentrations from chemical stabilization treated
cells as compared to leachate concentrations from untreated cells.
Table 6-4: Percent Reduction - All Treatment Types
Constituent
Average
Minimum
Maximum
Technology
Source
Notes
Percent
Percent
Percent
(location
Reduction
Reduction
Reduction
within
source)
All constituents reported as dissolved
Aluminum
99.96%
99.80%
99.99%
Lime
Trudnowski,
2004
Table 4-2
Arsenic
99.89%
97.19%
99.98%
Lime
Trudnowski,
2004
Appendix A
Iron
100.00%
99.99%
100.00%
Lime
Trudnowski,
2004
Table 4-3
Sulfate
95.32%
74.14%
99.52%
Lime
Trudnowski,
2004
Table 4-4
Zinc
99.91%
99.72%
99.99%
Lime
Trudnowski,
2004
Appendix A
Aluminum
99.98%
99.91%
100.00%
MT2
Envirobond
Trudnowski,
2004
Table 5-2
Arsenic
-38.04%
2,032.45%
93.14%
MT2
Envirobond
Trudnowski,
2004
Appendix A
Iron
99.99%
99.95%
100.00%
MT2
Envirobond
Trudnowski,
2004
Table 5-3
Sulfate
-275.04%
2,313.89%
88.37%
MT2
Envirobond
Trudnowski,
2004
Table 5-4
Zinc
99.62%
97.99%
99.99%
MT2
Envirobond
Trudnowski,
2004
Appendix A
6-9
-------
Chemical Stabilization
Table 6-4: Percent Reduction - All Treatment Types
Constituent
Average
Minimum
Maximum
Technology
Source
Notes
Percent
Percent
Percent
(location
Reduction
Reduction
Reduction
within
source)
Aluminum
99.97%
99.91%
100.00%
Potassium
Permanganate
Passivation
Trudnowski,
2004
Table 6-2
Arsenic
99.07%
99.20%
99.99%
Potassium
Permanganate
Passivation
Trudnowski,
2004
Appendix A
Iron
99.99%
99.91%
100.00%
Potassium
Permanganate
Passivation
Trudnowski,
2004
Table 6-3
Sulfate
73.43%
-34.71%
96.20%
Potassium
Permanganate
Passivation
Trudnowski,
2004
Table 6-4
Zinc
99.83%
98.52%
99.99%
Potassium
Permanganate
Passivation
Trudnowski,
2004
Appendix A
Aluminum
88.14%
5.78%
99.87%
SME
Trudnowski,
2004
Table 7-2
Arsenic
93.90%
84.12%
99.95%
SME
Trudnowski,
2004
Appendix A
Iron
94.82%
53.81%
99.99%
SME
Trudnowski,
2004
Table 7-3
Sulfate
33.18%
-316.78%
90.23%
SME
Trudnowski,
2004
Table 7-4
Zinc
85.19%
-17.03
98.69%
SME
Trudnowski,
2004
Appendix A
Notes:
Date range = 2001-2002
Minimum and maximum percent reductions for aluminum, iron, and sulfate were obtained from
comparison of values for each of the sampling dates having reported values in the tables indicated;
average percent reductions were stated in the tables. Data reported in Appendix A were used to
calculate date-specific percentage reductions for arsenic and zinc and those were compared across the
sampling dates to determine the minimum and maximum percentage reductions; average percentage
reductions were calculated from all data reported.
Lime treatment can reduce the concentrations of aluminum, arsenic, and iron leached from waste rock
by more than 95 percent, relative to leachate from untreated waste rock; reduction in sulfate leachate
concentrations ranges from 74 to 99.5 percent. Greater than 98 percent reduction in leachate
concentrations of aluminum, iron and zinc are evident with MT2 Envirobond treatment; however, MT2
Envirobond is not able to achieve positive reductions of leachate concentrations of either arsenic or
sulfate. Potassium permanganate treatment can achieve reductions of leachate concentrations for
6-10
-------
Chemical Stabilization
aluminum, arsenic, iron and zinc of greater than 98 percent, relative to untreated waste rock leachate.
However, reduction in leachate concentration of sulfate by potassium permanganate treatment is more
variable, with a range from below zero to 96 percent. Percentage reductions in leachate concentrations
from silica microencapsulation are the most varied of the treatments, with maximum reductions greater
than 90 percent for all constituents, but minimum reductions below zero for sulfate and zinc, < 10
percent for aluminum, 54 percent for iron and 84 percent for arsenic.
6.4.4 Flow Rates
Flow rates were not provided in the case study evaluated.
6.5 Costs
Conceptual design costs for each of the four treatment technologies, based on hypothetical treatment
of 750,000 tons of waste rock, are as follows: silica microencapsulation = $12,682,998; potassium
permanganate passivation = $3,241,408; MT2 Envirobond = $4,034,750; and lime = $4,774,438
(Trudnowski, 2004).
6.6 Lessons Learned
• Some chemicals used in the chemical stabilization technology are more effective than others
(Trudnowski, 2004; Nordwick et al., 2006).
• Lime treatment may need multiple applications to maintain effectiveness because it is soluble
and will dissolve overtime (Trudnowski, 2004; Nordwick et al., 2006).
• Chemical stabilization treatment performance can vary over time.
o Silica microencapsulation performed well in the short-term. Increasing the dosage may
solve the longevity issue; however it would increase costs for an already expensive
treatment (Trudnowski, 2004; Nordwick et al., 2006).
• Although chemical stabilization treatments reduce concentrations of elements and acidity
leached from waste rock, concentrations in leachate may still exceed site-specific discharge
criteria (Trudnowski, 2004; Nordwick et al., 2006).
• Some of the chemical stabilization technologies evaluated may result in unfavorable conditions
that may require treatment modification. MT2 Envirobond application may increase arsenic and
sulfate levels; lime treatment may result in pH values that exceed site-specific discharge criteria
and require adjustment prior to discharge (Trudnowski, 2004; Nordwick et al., 2006).
6.7 References
6.7.1 Case Study References
Nordwick, S., Zaluski, M., Park, B., and Bless, D. 2006. "Advances in Development of Bioreactors
Applicable to the Treatment of ARD." Paper presented at the 7th International Conference on Acid Rock
Drainage (ICARD), St. Louis, MO, March 26-30, 2006. pp. 1410-1420. R.I. Barnhisel (Ed.), Published by
ASMR, Lexington, KY.
Trudnowski, J. 2004. Mine Waste Technology Program, Remediation Technology Evaluation at Gilt Edge
Mine, South Dakota. US Environmental Protection Agency (U.S. EPA) National Risk Management
Research Laboratory. (EPA/600/R-05/002). 38 pp.
6-11
-------
Chemical Stabilization
6.7.2 General Chemical Stabilization References
Interstate Technology and Regulatory Council (ITRC) Mining Waste Team. 2010. Chemical Stabilization:
Phosphate and Biosolids Treatment. Washington, D.C. www.itrcweb.org.
6-12
-------
Constructed Wetlands
7 Constructed Wetlands
Characteristics of wetlands include saturated soil conditions (hydric soil), a water cover at or near the
surface for at least part of the year, and vegetation that is adapted to surviving in hydric soils.
Constructed wetlands are created specifically to treat metals or other contaminants present in
groundwater or surface water that is directed to flow through them (U.S. EPA, 1994).
There are two primary types of constructed wetlands: aerobic and anaerobic. Aerobic, or surface-flow
wetlands, consist of wetland vegetation planted in shallow (<30 centimeter [cm]) organic substrates and
treat net-alkaline water, whereas anaerobic, or sub-surface flow wetlands, have vegetation planted in
deeper (>30 cm) substrates and treat net acidic water. Both types of constructed wetlands may include
limestone either as a base or mixed in with the organic substrate (Skousen and Ziemkiewicz, 2005).
The primary function of an aerobic wetland is to allow oxidation and precipitation of high concentrations
of iron to ferric oxyhydroxides in net-alkaline or slightly acidic water (Zipper et al., 2011). Anaerobic
wetlands are similar to biochemical reactors (BCRs), although BCRs do not contain vegetation. Anaerobic
wetlands are designed to include limestone specifically to provide alkalinity to neutralize acidity of the
mining-influenced water (MIW) (Zipper et al., 2011) and treat metals present through reactions
occurring under reducing conditions, such as by the formation of metal sulfides (Skousen and
Ziemkiewicz, 2005).
Constructed wetlands are designed to treat contaminants over a long period and can be used as the sole
technology or as part of a larger treatment approach, such as an aerobic wetland operating as a
polishing step for effluents from BCRs or other anaerobic or alkalinity-producing processes.
Contaminants may be removed from MIW through plant uptake, volatilization (e.g., arsenic, mercury,
selenium), oxidation/reduction (chemical and/or microbial), precipitation, and adsorption. Some
treatment systems use both aerobic and anaerobic wetlands for complete treatment of a variety of
metals and acidity in MIW. Constructed wetlands are often used as part of a treatment train (see Section
10).
7.1 Case Studies Evaluated
This chapter provides an evaluation of case studies in which a constructed wetland was the sole
treatment for MIW (i.e., not part of a treatment train). The case studies evaluated were based on the
criteria presented in Section 1.1.1. The case studies include two mine sites: one having an aerobic
constructed wetland and the other having an anaerobic constructed wetland (Table 7-1). This chapter
provides considerations for constraints, treatability of contaminants, capability, technological and site-
specific requirements, costs, and lessons learned for constructed wetlands treatment from evaluation of
these case studies. Because only a single study was evaluated for each type of wetland that met this
study's criteria and the criteria of having data specifically for a wetland component, it is not possible to
provide evaluation of either anaerobic or aerobic wetlands on a technology-wide basis.
7-1
-------
Constructed Wetlands
Table 7-1: Constructed Wetlands Case Study Sites
Site Name
Wetland
Description
Study
Reference
Reference
and Location
Type
Type
Type
Copper Basin
Anaerobic
Two-acre anaerobic wetland
Pilot
Federal
FRTR Case
Mining
followed
constructed with a
scale
Remediation
Study
District,
by aerobic
geosynthetic clay liner
Technologies
summary
Copper Hill,
overlain with lime-enriched
Roundtable
(online
Tennessee
soil, crushed limestone, hay,
(FRTR), 2007
document)
mushroom compost and
U.S. EPA,
Report
planted with cattails. After
2006b
four years, two aerobic cells
Faulkner and
Conference
and an aerobic limestone
Miller, 2002
paper
rock filter were added.
(anaerobic
only)*
Dunka Mine,
Aerobic
Five unconnected surface
Full scale
Eger and
Conference
Babbitt,
flow wetland treatment
Eger, 2005*
paper
Minnesota
systems. Each system
included a series of soil
Eger et al.,
Conference
berms, covered in local peat
1996
paper
and peat screenings, built to
Eger et al.,
Conference
control water levels and
1998
paper
maximize contact between
ITRC, 2010*
Report
the drainage and the
Eger and
Journal
substrate. The berms were
Beatty, 2013
paper
hand-seeded with Japanese
millet, while open water
areas were seeded with
cattails.
Notes:
* Primary source(s) of data for evaluation in this chapter
7.2 Constraints
A primary constraint associated with constructed wetlands treatment is the need for suitable land space
and topography to accommodate the wetland system. A wetland's effective treatment area needs to be
large enough to allow enough time for the reactions to occur at the anticipated influent flow rate and
constituent concentrations (Eger and Eger, 2005).
Additional constraints of constructed wetlands treatment include:
• Some locations might be unsecured and have a potential for vandalism, which would need to be
considered in the wetland design (Faulkner and Miller, 2002).
• Treatment may be insufficient to meet numeric effluent limits consistently (Interstate
Technology and Regulatory Council [ITRC], 2010).
• A challenge specific to anaerobic wetlands is the need to maintain appropriate water levels and
deep subsurface flow to facilitate anaerobic processes (Faulkner and Miller, 2002).
7-2
-------
Constructed Wetlands
• Depending on the waste stream, there may be a need to limit human or ecological exposure to
the metals sequestered in the wetland.
7.3 Treatable Contaminants
Anaerobic constructed wetlands can treat aluminum, copper, iron, zinc and sulfate, and raise pH
(Faulkner and Miller, 2002), although based on a single study. Constructed aerobic wetlands can treat
cobalt, copper, nickel and zinc (Eger and Eger, 2005; ITRC, 2010).
7.4 Capability - Anaerobic
7.4.1 Ranges of Applicability
The single case study evaluated did not provide date-specific corresponding influent and effluent
concentrations for the constructed wetlands. Therefore, the range of applicability for anaerobic
constructed wetlands could not be ascertained.
7.4.2 Average Influent and Effluent Concentrations
Table 7-2 lists the average influent concentration treated for each constituent from Appendix D, Table
D-l.
Table 7-2: Average Influent Concentration Treated
Constituent
Average
Influent3
Concentration
Average Effluent3
Concentration
Mine
Source
Concentrations reported as total in mg/L, except total or dissolved not stated for sulfate; pH reported
in standard units
Aluminum
2.351
0.073
Copper Basin
Faulkner and Miller, 2002
Copperb
0.311
0.008
Copper Basin
Faulkner and Miller, 2002
Iron
1.07
0.353
Copper Basin
Faulkner and Miller, 2002
Manganese
1.52
1.64
Copper Basin
Faulkner and Miller, 2002
Zinc
1.094
0.045
Copper Basin
Faulkner and Miller, 2002
Sulfate
142
128
Copper Basin
Faulkner and Miller, 2002
PH
4.2
7.1
Copper Basin
Faulkner and Miller, 2002
Notes:
a = From 9/8/1999 to 1/1/2002
b = Average influent and effluent concentrations of 0.43 mg/L and less than 0.025 mg/L, respectively,
during the first six months of operation, from 10/1998 through 3/1999
Although the average influent and effluent concentrations are not corresponding concentrations, on
average, concentrations of aluminum, iron, copper and zinc are decreased by one to two orders of
magnitude from treatment by an anaerobic wetland. Anaerobic constructed wetlands also can raise pH
from acidic (4.2) to neutral levels (7.1). In the study examined, Table 7-2 shows that, on average, there is
minimal or no treatment of sulfate and manganese, with their average effluent concentrations being
greater than (manganese) or within 10 percent of (sulfate) their average influent concentrations.
7-3
-------
Constructed Wetlands
7.4.3 Removal Efficiency
Table 7-3 summarizes average removal efficiencies, calculated by EPA using the average influent and
effluent concentrations presented in Table 7-2.
Table 7-3: Average Removal Efficiencies
Constituent
Average Removal
Efficiency3
Mine
Source
All results reportec
as total except sulfate
not stated)
Aluminum
96.9%
Copper Basin
Faulkner and Miller, 2002
Copper
97.4%
Copper Basin
Faulkner and Miller, 2002
Copperb
94.2%
Copper Basin
Faulkner and Miller, 2002
Iron
67.0%
Copper Basin
Faulkner and Miller, 2002
Manganese
-7.9%
Copper Basin
Faulkner and Miller, 2002
Zinc
95.9%
Copper Basin
Faulkner and Miller, 2002
Sulfate
9.9%
Copper Basin
Faulkner and Miller, 2002
Notes:
a = Average removal efficiencies calculated by EPA
b = Based on influent and effluent averages provided for first six months of operation,
beginning 10/1998
As shown in Table 7-3, average removal efficiencies from anaerobic constructed wetlands treatment for
aluminum, copper and zinc exceed 94 percent. The anaerobic constructed wetlands did not treat
manganese and average removal efficiency for sulfate is low (<10 percent).
7.4.4 Flow Rates
Maximum and minimum average flow rates treatable in a constructed anaerobic wetland are not known
from the currently available data. Average influent flow treatable by a constructed anaerobic wetland is
992 L/min (Faulkner and Miller, 2002).
7.5 Capability - Aerobic
Only a single case study (Eger and Eger, 2005) was evaluated that met the screening criteria (see Section
1.1.1) for this work. The case study examined five unconnected wetlands; however, only one wetland
and its expansion could be considered as sole treatment systems. Therefore, the discussion of the
capability of aerobic wetlands is limited.
7.5.1 Ranges of Applicability
The range of applicability for aerobic constructed wetlands treatment of nickel is provided in Table 7-4,
based on the single case study examined (Eger and Eger, 2005). No corresponding influent and effluent
concentrations were provided for other constituents.
7-4
-------
Constructed Wetlands
Table 7-4: Maximum and Minimum Influent and Corresponding Effluent Concentrations
Constituent
Maximum
Influent
Cone.
Corresponding
Effluent Cone.
Minimum
Influent
Cone.
Corresponding
Effluent Cone.
Mine-
Wetland
Source
Concentrations reported in mg/L, total or dissolved not stated
Nickel
8
0.006
0.15
0.04
Dunka -
W1D
Eger and
Eger,
2005
Notes:
Values extracted from a line graph (Figure 8, Eger and Eger, 2005)
As shown in Table 7-4, aerobic constructed wetland treatment is capable of reducing nickel
concentrations from both maximum and minimum influent concentrations and can decrease nickel
concentrations by one to three orders of magnitude.
7.5.2 Average Influent and Effluent Concentrations
Concentrations of metals tend to be inversely related to the pH, with higher concentrations associated
with a lower pH and lower concentrations associated with a higher pH. Tables 7-5 and 7-6 list the
highest and lowest average influent concentrations (and lowest and highest pH) treated for each
constituent, respectively. Tables 7-7 and 7-8 list the highest and lowest average effluent concentrations
(and lowest and highest pH) attained for each constituent, respectively. Values in Tables 7-5 through
Table 7-8 were determined by comparison of values in Appendix D, Table D-l, developed as discussed in
Section 1.1.2. As discussed in Section 1.1.2 of the Introduction, it is important to note that the average
influent concentrations do not correspond directly with the average effluent concentrations.
Table 7-5: Maximum Average Influent Concentration Treated
Constituent
Maximum
Average
Influent
Concentration
Average Effluent
Concentration
Mine-Wetland
Source(s)
Concentrations reported in mg/L, total or dissolved not stated; pH reported in standard units
Cobalt3
0.036
0.008
Dunka-W1D
Eger and Eger, 2005; ITRC,
2010
Copperb
0.068
0.008/0.010
Dunka-W1D
Eger and Eger, 2005; ITRC,
2010
Nickelb
3.98
0.36/0.700
Dunka-W1D
Eger and Eger, 2005; ITRC,
2010
Zinca
0.052
0.013
Dunka-W1D
Eger and Eger, 2005; ITRC,
2010
PH
7.07
7.18
Dunka-W1D
Expanded
Eger and Eger, 2005; ITRC,
2010
Notes:
a = Two sampling periods had the same maximum average influent concentration reported and the
same average effluent concentration reported
7-5
-------
Constructed Wetlands
Table 7-5: Maximum Average Influent Concentration Treated
Constituent
Maximum
Average Effluent
Mine-Wetland
Source(s)
Average
Concentration
Influent
Concentration
Concentrations reported in mg/L, total or dissolved not stated; pH reported in standard units
b = Two sampling periods had the same maximum average influent concentration reported, but
different average effluent concentrations reported
Table 7-6: Minimum Average Influent Concentration Treated
Constituent
Minimum
Average
Influent
Concentration
Average Effluent
Concentration
Mine-Wetland
Source(s)
Concentrations reported in mg/L, total or dissolved not stated; pH reported in standard units
Cobalt3
0.009
0.001
Dunka -W1D;
Dunka-W1D
Expanded
Eger and Eger, 2005
Copper3
0.02
0.002
Dunka-W1D;
Dunka-W1D
Expanded
Eger and Eger, 2005
Nickel3
0.74
0.19/0.18
Dunka-W1D;
Dunka-W1D
Expanded
Eger and Eger, 2005
Zinc
0.017
0.011
Dunka-W1D
Expanded
ITRC, 2010
PH
7.30
7.48
Dunka-W1D
Eger and Eger, 2005
Notes:
a = Dunka - W1D and Dunka - W1D Expanded had identical concentrations reported for some
sampling periods
Table 7-7: Maximum Average Effluent Concentration Attained
Constituent
Maximum
Average
Effluent
Concentration
Average Influent
Concentration
Mine-Wetland
Source(s)
Concentrations reported in mg/L, total or dissolved not stated; pH reported in standard units
Cobalt3
0.008
0.036
Dunka-W1D
Eger and Eger, 2005; ITRC,
2010
Copper
0.010
0.068
Dunka-W1D
ITRC, 2010
Nickel
0.700
3.98
Dunka -W1D
ITRC, 2010
7-6
-------
Constructed Wetlands
Table 7-7: Maximum Average Effluent Concentration Attained
Constituent
Maximum
Average
Effluent
Concentration
Average Influent
Concentration
Mine-Wetland
Source(s)
Zinca
0.013
0.052
Dunka-WID
Eger and Eger, 2005; ITRC,
2010
PH
7.18
7.07
Dunka-WID
Expanded
Eger and Eger, 2005; ITRC,
2010
Notes:
a = Two sampling periods had the same maximum average effluent concentration reported and the
same average influent concentration reported
Table 7-8: Minimum Average Effluent Concentration Attained
Constituent
Minimum
Average
Effluent
Concentration
Average Influent
Concentration
Mine-Wetland
Source(s)
Concentrations reported in mg/L, total or dissolved not stated; pH reported in standard units
Cobalt3
0.001
0.009/0.023
Dunka-WID
and W1D
Expanded
Eger and Eger, 2005; ITRC,
2010
Copperb
0.002
0.02
Dunka-WID
and W1D
Expanded
Eger and Eger, 2005
Nickel
0.099
0.76
Dunka-WID
Expanded
Eger and Eger, 2005
Zinca
0.006
0.019/0.021
Dunka-WID
Eger and Eger, 2005; ITRC,
2010
PH
7.48
7.30
Dunka-WID
Eger and Eger, 2005
Notes:
a = Some sampling periods and locations had the same minimum average effluent concentration
reported, but different average influent concentrations reported
b = Dunka - W1D and Dunka - W1D Expanded had identical concentrations reported for some
sampling periods
Aerobic constructed wetlands in the examined study can treat both the highest and lowest average
influent concentrations of all constituents, as shown by the maximum average effluent concentrations
(Table 7-7) being lower than both maximum (Table 7-5) and minimum (Table 7-6) average influent
concentrations. On average, cobalt and copper are decreased by one order of magnitude relative to
both maximum and minimum average influent concentrations when comparing data in Tables 7-5 and 7-
6 with Table 7-7. On average, decreases in nickel concentration are less than an order of magnitude to
more than an order of magnitude, relative to lower and higher average influent concentrations,
respectively. Aerobic constructed wetlands treatment can reduce cobalt, copper and zinc
7-7
-------
Constructed Wetlands
concentrations, on average, to 13 \x.g/\ or below and nickel to 700 ng/l or below, as shown by the
maximum and minimum average effluent concentrations in Tables 7-7 and 7-8, respectively. Aerobic
constructed wetlands do not generally affect pH when influent concentrations are near neutral (pH ~7),
as indicated by both maximum and minimum average pH values being similar (pH 7.2 to ~7.5).
7.5.3 Removal Efficiency
Tables 7-9 and 7-10 present the maximum and minimum average removal efficiencies, respectively,
determined from comparison of values in Appendix D, Table D-2.
Table 7-9: Maximum Average Removal Efficiencies
Constituent
Maximum Average
Removal Efficiency3
Mine-Wetland
Source
Total or dissolved not stated
Cobalt
95.7%
Dunka-WID
Expanded
ITRC, 2010
Copper
91.5%
Dunka-WID
Expanded
ITRC, 2010
Nickel
91%
Dunka-WID
Eger and Eger, 2005
Zinc
75%
Dunka-WID
Eger and Eger, 2005
Notes:
a = Average removal efficiencies calculated by EPA
Table 7-10: Minimum Average Removal Efficiencies
Constituent
Minimum Average
Removal Efficiency3
Mine-Wetland
Source
Total or dissolved not stated
Cobalt
77.8%
Dunka-WID
Eger and Eger, 2005; ITRC, 2010
Copper
83.3%
Dunka-WID
Expanded
Eger and Eger, 2005
Nickel
74.3%
Dunka-WID
Eger and Eger, 2005
Zinc
35.3%
Dunka-WID
Expanded
ITRC, 2010
Notes:
a = Average removal efficiencies calculated by EPA
The maximum average removal efficiencies for aerobic constructed wetlands treatment range from 75
percent (zinc) to about 96 percent (cobalt) (Table 7-9). The minimum average removal efficiencies range
from about 35 percent (zinc) to about 83 percent (copper) (Table 7-10). Except for zinc, aerobic
constructed wetlands treatment has a minimum removal efficiency of greater than 74 percent for all
metals in Table 7-10. Aerobic constructed wetlands treatment is less efficient and the most varied for
zinc relative to the other metals examined, with average removal efficiencies ranging from 35 percent to
75 percent.
7-8
-------
Constructed Wetlands
Average removal efficiencies for cobalt, copper and nickel decrease after the first one to five years of
treatment but rebound to similar or higher average removal efficiencies after nearly a decade of
treatment (Appendix D, Table D-2). Because only the one site was evaluated, this trend may or may not
be typical of aerobic wetlands.
7.5.4 Flow Rates
Average flow rates over time for the aerobic constructed wetlands are provided in Table 7-11.
Table 7-11: Average Flow Rates
Average Flow Rate
Time Period
Mine-Wetland
Source
All rates are in L/min
125
1992 to 1994
Dunka-WID
Eger and Eger, 2005
150
1992 to 1997
Dunka-WID
ITRC, 2010
57
1996 to 1998
Dunka-WID
Eger and Eger, 2005
38
1999 to 2004
Dunka-WID
Eger and Eger, 2005
130
1995 to 1997
Dunka-WID
Expanded
ITRC, 2010
57
1996 to 1999
Dunka-WID
Expanded
Eger and Eger, 2005
Average influent flow treatable by aerobic constructed wetlands ranges between 38 L/min and 150
L/min (Eger and Eger, 2005; ITRC, 2010). Future case study comparisons may provide additional
information on the flow capabilities of the treatment.
7.6 Costs
Costs specific to anaerobic constructed wetlands were unavailable in the case studies reviewed. Costs
for aerobic constructed wetlands range from about $18 per square meter (m2) to $28/m2 (ITRC, 2010).
Costs for aerobic constructed wetlands vary by size, design and material construction of the wetland.
7.7 Lessons Learned
• Performance of wetlands is highly dependent on size, reactive surface area and metal loading
rates (flow x concentration), where adequate retention time to ensure metal removal governs
wetland size requirements (ITRC, 2010; Eger et al., 1998).
• Efficiency of aerobic wetlands treatment may decrease when temperatures decrease (ITRC,
2010).
• Anaerobic wetlands treatment is ineffective for manganese removal, but reduction in the
concentration of manganese is possible through use of aerobic wetlands and limestone rock-
filters (e.g., Copper Basin,FRTR, 2007).
• Limestone rock-filters placed downstream from anaerobic wetlands are useful for allowing gases
produced in anaerobic systems to volatilize, providing for oxygen diffusion to the water and
oxidation of metals that are more easily removed in aerobic processes, and settling of oxidized
precipitates (FRTR, 2007).
7-9
-------
Constructed Wetlands
7.8 References
7.8.1 Case Study References
Eger, P., Wagner, J., and Melchert, G. 1996. "The Use of Overland Flow Wetland Treatment Systems to
Remove Nickel from Neutral Mine Drainage. "Paper presented at the 1996 Annual Meeting of the
American Society for Surface Mining and Reclamation (ASSMR), Knoxville, TN, May 18-23. pp. 580-589.
Eger, P., Melchert, G., and Wagner, J. 1998. "Mine closure - Can passive treatment be successful." In
Proceedings of 15th Annual Meeting of American Society for Surface Mining and Reclamation, St. Louis,
MO, May 17-21, 1998. pp. 263-271.
Eger, P. and Beatty, C.L.K. 2013. "Constructed Wetland Treatment Systems for Mine Drainage - Can
They Really Provide Green and Sustainable Solutions?" Paper presented at the 2013 International Mine
Water Conference, pp. 545-550. Wolkersdorfer, Brown & Figueroa (Ed.).
Eger, P. and P. Eger. 2005. "Controlling Mine Drainage Problems in Minnesota - Are All the Wetland
Treatment Systems Really Above Average?" Paper presented at the 2005 National Meeting of the
American Society of Mining and Reclamation, June 19-13, 2005. Published by ASMR, Lexington, KY. pp.
339-359.
Faulkner, B.B. and F.K. Miller. 2002. "Improvement of Water Quality by Land Reclamation and Passive
Systems at an Eastern U.S. Copper Mine." Paper presented at the 2002 National Meeting of the
American Society of Mining and Reclamation, Lexington, KY, June 9-13, 2002. pp. 830-841.
Federal Remediation Technologies Roundtable (FRTR). 2007. "Constructed Wetland at Copper Basin
Mining District, in Cost and Performance Case Studies." Accessed August 22, 2019.
https://frtr.gov/costperformance/pdf/20070522 397.pdf.
Interstate Technology and Regulatory Council (ITRC) Mining Waste Team. 2010. Dunka Mine, Minnesota.
Mining Waste Treatment Technology Selection Web. Washington, D.C., 2010. www.itrcweb.org.
U.S. Environmental Protection Agency (U.S. EPA). 2006b. Abandoned Mine Lands Innovative Technology
Case Study, Copper Basin Mining District. 2006. https://semspub.epa.gov/work/04/11121242.pdf.
7.8.2 General Constructed Wetlands References
Skousen, J. and Ziemkiewicz, P. 2005. "Performance of 116 Passive Treatment Systems for Acid Mine
Drainage." In proceedings of 2005 National Meeting of the American Society of Mining and Reclamation,
Breckenridge, CO, June 19-23, 2005. Published by the ASMR, Lexington, KY. pp. 1100-1133.
http://www.asmr.us/Portals/0/Documents/Conference-Proceedings/2005/1100-Skousen.pdf.
U.S. Environmental Protection Agency (U.S. EPA). 1994. A Handbook of Constructed Wetlands: A Guide
to Creating Wetlands for: Agricultural Wastewater, Domestic Wastewater, Coal Mine Drainage,
Stormwater in the Mid-Atlantic Region. 46 pp. https://www.epa.gov/sites/production/files/2015-
10/documents/constructed-wetlands-handbook.pdf.
Zipper, C., Skousen, J., and Jage, C. 2011. Passive treatment of acid mine drainage, Powell River Project.
Virginia Cooperative Extension, 460-133.
7-10
-------
Constructed Wetlands
https://vtechworks.lib.vt.edu/bitstream/handle/10919/56136/460-133.pdf?sequence=l. Last accessed
10/22/18.
7-11
-------
In Situ Treatment of Mine Pools and Pit Lakes
8 In-Situ Treatment of Mine Pools and Pit Lakes
ln-situ treatment of mine pools and pit lakes includes physical (e.g., stratification), chemical (e.g., adding
lime) and/or biological (e.g., enhancing sulfate-reducing bacterial activity) mechanisms (McCullough,
2008; ITRC, 2010; Fisher and Lawrence, 2006). Addition of lime is proven and effective but may be too
expensive to maintain long-term (McCullough, 2008). Biological in-situ treatment involves adding carbon
and/or nutrient amendments to encourage growth of plankton that will adsorb constituents and then
carry them to the sediments as they sink after death (Poling et al., 2003; Fisher and Lawrence, 2006) or
sulfate-reducing bacteria that facilitate precipitation of metal sulfides (Harrington et al., 2015).
Depending on site-specific conditions, delivery of organic carbon can be at an upgradient area of the
mine, where treatment would then occur along the flow path, directly into a pit lake, or added to water
pumped from mine workings, mixed at the surface and recirculated back into the mine workings
(Harrington et al., 2015). The form of organic carbon chosen is generally based on residence time of the
water in the pit or pool, with alcohol-base reagents, such as methanol, used for residence times on the
order of weeks and slower degrading sugar or starches (molasses) used for mine pools with longer
residence times (several months or longer) (Harrington, 2015). The injection frequency ranges from
months to years based on water quality improvements observed and the rate of re-oxidation of water or
constituents (Harrington et al., 2015). Water treatment plant sludge containing ferric oxyhydroxide
precipitates can also be applied to enhance mine pool treatment (Harrington et al., 2015). Mine pool
treatments have to take into consideration whether there is a surface water discharge or a connection
with groundwater serving public water supplies.
8.1 Case Studies Evaluated
This chapter provides an evaluation of case studies in which mine pool or pit lake water was treated
primarily in situ. The case studies were selected based on the criteria presented in Section 1.1.1. The
case studies examined included one mining site in the United States and one in Canada. Table 8-1
summarizes site names and locations, treatment design information, and references for each of the case
studies. The chapter provides considerations for constraints, treatability of contaminants, capability,
technological and site-specific requirements, and lessons learned for in-situ mine pool and pit lake
treatment from evaluation of case study results.
Capability considerations for pit lakes and mine pools are evaluated separately in this chapter as they
likely have different chemistries. Pit lakes are exposed to oxygen and may be stratified. Mine pools are
underground and usually have less exposure to oxygen. Delivery to a mine pool can be complicated as is
the ability to characterize if the mine in inaccessible and old.
Table 8-1: In Situ Mine Pools and Pit Lakes Case Study Sites
Site Name
and
Location
Type
Description
Study Type
Reference
Reference
Type
Island
Copper
Mine
Pit Lake
Seawater and
freshwater capping
(stratification);
liquid fertilizer,
applied across the
Full scale
Poling et al.,
2003*
Conference
paper
Fisher and
Lawrence,
2006*
Journal paper
8-1
-------
In Situ Treatment of Mine Pools and Pit Lakes
Table 8-1: In Situ Mine Pools and Pit Lakes Case Study Sites
Site Name
Type
Description
Study Type
Reference
Reference
and
Type
Location
British
surface of the lake
Columbia,
during summer
Canada
1997-2000 and
then every 7-10
days from June
2001a
Platoro
Underground
Single annual
Full scale
Harrington et
Conference
Mine
Mine Pool
soluble carbon
al., 2015*
paper
Colorado,
injections
United
supplemented with
States
metal hydroxide
sludge from a lime-
based water
treatment plant
(WTP) mixed with
potato or corn
starch
Notes:
* Primary source(s) of data for evaluation in this chapter
a = It is not clear from the sources if the applications in 1997-2000 were daily over the summer
months or at some interval
8.2 Constraints
The case studies exampled did not identify constraints.
8.3 Treatable Contaminants
Based on the two studies examined, in-situ treatment of mine pools and pit lakes can decrease
concentrations of arsenic, cadmium, copper, zinc and sulfate. Future case study comparisons may
provide additional information on treatable contaminants.
8.4 Capability- Pit Lakes
The inclusion of only two case studies (Poling et al., 2003; Fisher and Lawrence, 2006) that met the
criteria (see Section 1.1.1) for this work limits the ability to determine the capability of pit lake
treatment, in general. Nevertheless, the following sections present capability data for the technology
based on the two case studies at a single site.
8.4.1 Ranges of Applicability
In order to assess the range of applicability, Table 8-2 presents the ranges in constituent concentrations
in the upper layer of the Island Copper pit lake prior to each amendment application, during the
8-2
-------
In Situ Treatment of Mine Pools and Pit Lakes
application periods, and post applications (i.e., interim period between applications), based on the data
available in the two examined case studies.
Table 8-2: Constituent Concentration Ranges Pre-, During and Post-Treatment - Island Copper Mine
Pit Lake
Constituent
Pre-treatment
During
Post-treatment
Treatment
Source
Concentration
Treatment
(between
Event
Range
Concentration
Range
applications)
Concentration
Range
Concentrations reported as disso
ved in mg/L
Cadmium
0.004a - 0.00513
0-0.006
NA
2001-2002
Poling et al.,
2003, Figure 8
Copper
0.0065-0.055
0.0055-
0.014
0.006-0.011
1997
Fisher and
Lawrence, 2006,
Figure 7
0.006-0.011
0.007-
0.0135
0.0045-0.008
1998
Fisher and
Lawrence, 2006,
Figure 7
0.0045-0.008
0.002-0.006
0.005-0.013
1999
Fisher and
Lawrence, 2006,
Figure 7
0.005-0.013
0.001-0.010
0.003b
2000
Fisher and
Lawrence, 2006,
Figure 7
0.003a-0.008
0.001-0.006
NA
2001-2002
Poling et al.,
2003, Figure 7
Zinc
0.3-0.6
0.01-0.59
0.01-0.25
1997
Fisher and
Lawrence, 2006,
Figure 7
0.01-0.025
0.01-0.42
0.15-0.38
1998
Fisher and
Lawrence, 2006,
Figure 7
0.15-0.38
0.01-0.18
0.17-0.24
1999
Fisher and
Lawrence, 2006,
Figure 7
0.17-0.24
0.08-0.22
0.20b
2000
Fisher and
Lawrence, 2006,
Figure 7
0.41a - 0.51a
O
1
o
k>
NA
2001-2002
Poling et al.,
2003, Figure 6
Notes:
a = March through May 2001 represents concentration prior to start of the continuous (treatment
every 10 days) treatment at 1-meter depth
b = Only one sampling date following application
NA = Not available; figures in source do not allow determining dates associated with post application
8-3
-------
In Situ Treatment of Mine Pools and Pit Lakes
As shown by differences between the pre- and during treatment ranges in Tables 8-2 in-situ treatment
to stimulate biological activity can decrease zinc concentrations over time in pit lake water. Results
suggest that consistent and continued in-situ treatment is necessary to sustain decreased
concentrations of constituents.
8.4.2 Average Pre-Treatment and Post-Treatment Concentrations
Average pre- and post-treatment concentrations were not provided in the references and were not
calculated from sources by EPA.
8.4.3 Removal Efficiency
Table 8-3 presents average removal efficiencies observed.
Table 8-3: Average Removal Efficiencies
Constituent
Average
Removal
Efficiency
Mine
Source
Notes
All constituents reported as dissolved
Cadmium
>90%
Island
Copper
Poling et al., 2003
Based on the results of the
18-month study
Copper
>90%
Island
Copper
Poling et al., 2003
Based on the results of the
18-month study
Zinc
>90%
Island
Copper
Poling et al., 2003
Based on the results of the
18-month study
Notes:
Cadmium and copper removal efficiencies stated in conclusion section of source
Zinc removal efficiency stated in text of source
As shown in Table 8-3, in-situ treatment of a pit lake can achieve an average removal efficiency of
greater than 90 percent for dissolved cadmium, copper and zinc.
8.4.4 Flow Rates
Pit lakes contain water from direct precipitation, groundwater inflow, and runoff and leachate from
mining wastes. Average annual daily and peak daily flow rates for the acid rock drainage (ARD) input to
the Island Copper pit lake are presented in Table 8-4.
Table 8-4: Average Flow Rate
Average Flow
Notes
Source
All rates are in liters per minute (L/min)
13.7
Annual Daily Average (North Injection System)
Fisher and Lawrence,
2006
8.8
Annual Daily Average (South Injection System)
Fisher and Lawrence,
2006
8-4
-------
In Situ Treatment of Mine Pools and Pit Lakes
Table 8-4: Average Flow Rate
Average Flow
Notes
Source
143
Peak Daily Flow
(North Injection System)
Fisher and Lawrence,
2006
137
Peak Daily Flow
(South Injection System)
Fisher and Lawrence,
2006
The average yearly ARD inflow to the pit lake was 4,321,600 million cubic meters ([7,190 + 4,650] x 365).
Fisher and Lawrence (2006) reported that flows to the Island Copper pit lake are "highly seasonal",
which can be seen by the order of magnitude difference between the annual daily average flows and the
peak daily flows in Table 8-4. It is not known if this behavior is typical of all pit lakes.
8.5 Capability - Mine Pools
The inclusion of only one case study (Harrington et al., 2015) that met the criteria (see Section 1.1.1) for
this work limits the ability to determine the capability of in situ mine pool treatment, in general.
Nevertheless, the following sections present capability data for the technology based on the single case
study.
8.5.1 Ranges of Applicability
In order to assess the range of applicability, Table 8-5 presents the ranges in constituent concentrations
in the Platoro mine pool prior to amendment applications and during the period between applications
(post-treatment).
Table 8-5: Constituent Concentration Ranges Pre- and Post-Treatment - Platoro Mine Pool
Constituent
Pre-treatment
Concentration
Range
Post-Treatment
(between
applications)
Concentration
Range
Treatment
Period
Source
Notes
Concentrations reported as dissolved in mg/L
Arsenic
2-51
<1-38
8/00 - 8/06a
Harrington et al., 2015
Figure 3
<1-38
<1-4
8/06 - 8/07
Harrington et al., 2015
Figure 3
<1-4
<1-2
8/07 - 8/08
Harrington et al., 2015
Figure 3
<1-2
1-2
8/08 - 8/09
Harrington et al., 2015
Figure 3
1-2
<1-2
8/09 - 8/10b
Harrington et al., 2015
Figure 3
<1-2
2.5-11
8/10-8/1 lb
Harrington et al., 2015
Figure 3
2.5-11
1-5
8/11-8/12
Harrington et al., 2015
Figure 3
1-5
<1-1
8/12b
Harrington et al., 2015
Figure 3
Sulfate
1,400-2,900
1,000-2,700
8/00 - 8/06a
Harrington et al., 2015
Figure 3
1,000-2,700
1,400-2,200
8/06 - 8/07
Harrington et al., 2015
Figure 3
1,400-2,200
1,400-2,000
8/07 - 8/08
Harrington et al., 2015
Figure 3
8-5
-------
In Situ Treatment of Mine Pools and Pit Lakes
Table 8-5: Constituent Concentration Ranges Pre- and Post-Treatment - Platoro Mine Pool
Constituent
Pre-treatment
Concentration
Range
Post-Treatment
(between
applications)
Concentration
Range
Treatment
Period
Source
Notes
1,400-2,000
820 -1,800
8/08 - 8/09
Harrington et al., 2015
Figure 3
820 -1,800
1,490-2,050
8/09 - 8/10b
Harrington et al., 2015
Figure 3
1,490-2,050
800 -2,250
8/10-8/1 lb
Harrington et al., 2015
Figure 3
800-2,250
180-400
8/11-8/12
Harrington et al., 2015
Figure 3
180-400
-------
In Situ Treatment of Mine Pools and Pit Lakes
Table 8-6: Average Removal Efficiencies
Constituent
Average
Removal
Efficiency
Mine
Source
Notes
All concentrations reported as dissolved
Arsenic
97%
Platoro
Harrington et al.,
2015
Based on the time period of
injections from 2006 to 2012
Zinc
93%
Platoro
Harrington et al.,
2015
Based on the time period of
injections from 2006 to 2012
Notes:
Arsenic and zinc removal efficiencies stated in text of source
As shown in Table 8-6, in-situ treatment of a mine pool can achieve an average removal efficiency of
greater than 90 percent for dissolved arsenic and zinc.
8.5.4 Flow Rates
Flow rates were not provided in the case study evaluated.
8.6 Costs
Costs were not stated specifically for either of the case studies of in-situ treatment of mine pools and pit
lakes; however, Poling et al. (2003) project that material costs for fertilizer, costs associated with
distribution of the fertilizer across the pit lake's surface (1,735,000 m2), and routine monitoring would
be less than $100,000 per year.
8.7 Lessons Learned
• Use of fertilizer with too high a nitrogen to phosphorus ratio (9:1) causes phosphorus-limited
growth and leaves some nitrogen unutilized (Poling et al., 2003). Residual nitrogen requires
reduction prior to sulfate reduction; therefore, unutilized nitrogen would slow sulfate-reduction
processes that are sequestering metals as metal sulfides. The revised ratio of nitrogen to
phosphorus, 6:1, leaves no nitrogen unutilized (Poling et al., 2003).
• At Island Copper, settling of organic matter containing adsorbed constituents through shallow to
deeper depths of a stratified pit lake is essential for success of biochemical in-situ treatment
(Poling et al., 2003).
• Blending denser carbon sources with alkaline ferric oxyhydroxide sludge allows targeting of
deeper zones of mine pools than would be otherwise accessible when pumping up and
amending mine water before returning the water through a second pipe (Harrington et al.,
2015).
8.8 References
8.8.1 Case Study References
Fisher, T.S.R and Lawrence, G.A. 2006. Treatment of Acid Rock Drainage in a Meromictic Mine Pit Lake.
Journal of Environmental Engineering, 32(4):515-526.
8-7
-------
In Situ Treatment of Mine Pools and Pit Lakes
Harrington, J., Harrington, J., Lancaster, E., Gault, A., and Woloshyn, K. 2015. "Bioreactor and In Situ
Mine Pool Treatment Options for Cold Climate Mine Closure at Keno Hill, YT." In proceedings from the
10th International Conference on Acid Rock Drainage and IMWA Annual Conference, Agreeing on
solutions for more sustainable mine water management, Gecamin, Santiago, Chile, 2015. pp. 1-10.
https://www.imwa.info/imwaconferencesandcongresses/proceedings/293-proceedings-2015.html
Poling, G.W., Pelletier, C.A., Muggli, D., Wen, M., Gerits, J., Hanks, C., and Black, K. 2003. "Field Studies
of Semi-Passive Biogeochemical Treatment of Acid Rock Drainage at the Island Copper Mine Pit Lake." In
proceedings from the 6th International Conference on Acid Rock Drainage (ICARD 2003), Queensland,
Australia, July 12-18. pp. 549-558.
8.8.2 General In Situ Treatment of Mine Pools and Pit Lakes References
Interstate Technology and Regulatory Council (ITRC) Mining Waste Treatment Technology Selection
Web. 2010. In Situ Treatment of Mine Pools and Pit Lakes, Minnesota. Washington, D.C..
www.itrcweb.org
McCullough, C.D. 2008. Approaches to remediation of acid mine drainage water in pit lakes.
International Journal of Mining, Reclamation and Environment, 22(2): 105-119.
8-8
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Permeable Reactive Barriers
9 Permeable Reactive Barriers
A permeable reactive barrier (PRB) is a subsurface in-situ zone consisting of a water permeable material
to treat constituents of concern in groundwater passing through it (Interstate Technology and
Regulatory Council [ITRC], 2011). PRBs are used in treating both organic and inorganic contaminants in
groundwater. Various materials are used individually or in combination in PRBs, including zero valent
iron, organic carbon, apatite, mulch, zeolites, red mud (waste material from bauxite ore processing) and
compost (ITRC, 2011; Benner at al., 2002; Conca and Wright, 2006 and Wright and Conca, 2006).
Mechanisms for treatment within a PRB can be physical, chemical, biological or a combination. Chemical
mechanisms include adsorption, ion exchange, oxidation-reduction or precipitation (Wright and Conca,
2006). Microbial communities can be stimulated by addition of organic carbon and nutrients to
biodegrade organic contaminants (ITRC, 2011) or facilitate conversion of inorganic constituents to
immobile precipitates (Conca and Wright, 2006; Wright and Conca, 2006), such as through the
formation of metal sulfides.
9.1 Case Studies Evaluated
This chapter provides an evaluation of case studies in which a PRB was a primary component of mining-
influenced water (MIW) treatment. The case studies were selected based on the screening criteria
presented in see Section 1.1.1. The case studies examined include full-scale installations of PRBs at two
mining sites: one in the United States and one in Canada. Table 9-1 summarizes site names and
locations, treatment design information and references for each of the case studies. The chapter
provides considerations for constraints, treatability of contaminants, capability, technological and site-
specific requirements, and lessons learned for PRBs from evaluation of case study results.
Table 9-1: PRB Case Study Sites
Site Name
Type and
Description
Study Type
Reference
Reference
and
Treatment
Type
Location
Material
Nickel Rim
Biological
PRB is 20 meters
Full scale
Benner et al.,
Journal paper
Mine
(stimulation
wide and 3.5
2002*
Ontario,
of sulfate
meters deep and is
Benner et al.,
Report
Canada
reducing
installed in
1999*
bacteria) and
alluvium and keys
Doshi, 2006
chemical
into bedrock at
(precipitation
base and sides. The
of iron
reactive layer is 4
sulfides).
meters thick
Treatment
between two layers
material is
of 1-meter thick
20% (by
sand. Treatment of
volume)
groundwater
municipal
plume originating
compost,
from a tailings
20% leaf
impoundment and
mulch, 9%
9-1
-------
Permeable Reactive Barriers
Table 9-1: PRB Case Study Sites
Site Name
Type and
Description
Study Type
Reference
Reference
and
Treatment
Type
Location
Material
woodchips,
infiltrated acidic
50% gravel
surface water.
and 1%
limestone.
Success
Biological
PRB consists of a
Full scale
Wright and
Conference
Mine and
(stimulation
442 meters (450-
Conca, 2006*
paper
Mill
of sulfate-
feet) pressure
Northern
reducing
grouted wall keyed
Conca and
Journal Paper
Idaho,
bacteria) and
into bedrock that
Wright, 2006*
United
chemical
directed
States
(precipitation
groundwater into a
McCloskey et
Conference
of metal
4.1x4.6x15.2
al., 2006
paper
sulfides).
meters (13.5 by 15
Treatment
by 50 feet) long
Doshi, 2006
Report
material is a
vault with two cells
biogenically-
containing the
precipitated
treatment
apatite
material.
material
Treatment of
from fish
groundwater
bones.
plume originating
from tailings pile.
Notes:
* Primary source(s) of data for evaluation in this chapter
9.2 Constraints
Small variations in hydraulic conductivity will decrease residence time, which will decrease performance
in PRBs that are limited by reaction rates (Benner, 2002). Accurate prediction of contaminant removal
rates depends on adequately accounting for changes in groundwater in systems where reactions are
microbially mediated (Benner, 2002). There is potential for odors to emanate from a PRB (McCloskey et
al, 2006), which may need to be controlled if the PRB is located near a populated area.
9.3 Treatable Contaminants
PRBs can treat aluminum, cadmium, copper, iron, lead, nickel, sulfate and zinc.
9.4 Capability
Only two case studies were identified that met the screening criteria (Section 1.1.1); therefore, the
limited data restricts the ability to determine the general capability for PRBs in treating mining-
influenced groundwater. In the sections below, influent concentration refers to the concentration of a
9-2
-------
Permeable Reactive Barriers
constituent in the groundwater entering the PRB and effluent concentration refers to the concentration
of a constituent in the groundwater after passing through the PRB.
9.4.1 Ranges of Applicability
Concentrations of metals tend to be inversely related to the pH, with higher concentrations associated
with a lower pH and lower concentrations associated with a higher pH. Table 9-2 lists maximum
(minimum pH) and minimum (maximum pH) influent concentrations of cadmium, lead and zinc and their
corresponding effluent concentrations from PRB treatment at the Success Mine and Mill. Table 9-3 lists
maximum and minimum upgradient groundwater concentrations of iron and sulfate and their
corresponding minimum concentrations both from within the PRB and downgradient from the PRB at
the Nickel Rim Mine.
Table 9-2: Maximum and Minimum Influent and Corresponding Effluent Concentrations - Success
Mine and Mill
Constituent
Maximum
Influent
Concentration
Corresponding
Effluent
Concentration
Minimum
Influent
Concentration
Corresponding
Effluent
Concentration
Source
Concentrations reported as dissolved in mg/L; pH reported in standard units
Cadmium
0.809
<0.002
0.318
<0.002
Conca and
Wright, 2006;
Wright and
Conca, 2006
Lead
1.45
<0.005
0.497
<0.005
Conca and
Wright, 2006;
Wright and
Conca, 2006
Zinc
146.9
0.059
44.7
0.027
Conca and
Wright, 2006;
Wright and
Conca, 2006
PH
4.2
7.1
5.5
6.9
Conca and
Wright, 2006;
Wright and
Conca, 2006
Notes:
< = Not detected above noted laboratory method detection limit
Data extracted from Table 1 (reported averages of two cells sampled between 03/23/01 and 6/9/04)
in Wright and Conca, 2006, and converted to mg/L
9-3
-------
Permeable Reactive Barriers
Table 9-3: Maximum and Minimum Upgradient Concentrations and Corresponding
Minimum Concentrations Within the PRB and Corresponding Concentration
Downgradient of the PRB - Nickel Rim Mine
Constituent
Maximum
Up-
Gradient
Cone.
Minimum
Cone.
Within
PRB
Down-
Gradient
Cone.
Minimum
Up-
Gradient
Cone.
Minimum
Cone.
Within
PRB
Down-
Gradient
Cone.
Source
Concentrations reported as dissolved in mg/L
Iron
670a
140a
357a
419c
IT
39c
Benner et
al, 2002
Sulfate
3,408a
865a
2,420a
2,594b
l,537b
l,824b
Benner et
al, 2002
Notes:
Data extracted from Figure 9, which presented vertically-averaged concentrations (4 wells in nest)
collected biannually between 11/95 and 10/98; converted from millimoles per liter
a = 10/98 sampling event
b = 5/98 sampling event
c = 6/96 sampling event
As shown in Tables 9-2 and 9-3, PRBs designed to stimulate biological sulfate reduction and subsequent
precipitation of metal sulfides can decrease concentrations of cadmium, iron, lead, sulfate and zinc as
well as increase pH from slightly acidic to near neutral. Table 9-2 shows decreases in both maximum and
minimum concentrations of cadmium and lead to below their detection limits. Zinc concentration also
decreases following exposure to a PRB, with resulting concentration in effluent less than 0.1 mg/L (Table
9-2) when treating influent concentrations up to four orders of magnitude higher. Table 9-3 shows iron
concentration can be reduced by up to an order of magnitude; sulfate concentration also is decreased
but is on the same order of magnitude in both upgradient and downgradient groundwater. Although
there are no corresponding data for alkalinity, Benner et al. (2002) noted that alkalinity increases as
sulfate and iron concentrations decrease.
Table 9-3 also shows that the concentrations of iron and sulfate are lower within the PRB than they are
downgradient of the PRB, which was explained by Benner et al. (2002) as possibly being due to a
combination of heterogenous flow through the PRB and sampling that is biased toward a volume
average. The case study at the Success Mine and Mill did not present data from within the PRB and no
other studies examined met the screening criteria for this report; therefore, it is not known if the
phenomenon observed by Benner et al. (2002) occurs at other sites having PRB treatment of
groundwater.
9.4.2 Average Influent and Effluent Concentrations
Tables 9-4 and 9-5 present average influent and effluent concentrations for constituents assessed in the
Success Mine and Mill case study and ranges in upgradient concentrations and averages in
concentrations of constituents within the PRB at the Nickel Rim Mine.
9-4
-------
Permeable Reactive Barriers
Table 9-4: Average Influent and Effluent Concentrations - Success Mine and Mill
Constituent
Average Influent
Concentration
Average Effluent
Concentration
Source
Notes
Concentrations reported as dissolved in mg/L; pH in standard units
Cadmium
0.521
0.0016
Conca and
Wright, 2006;
Wright and
Conca, 2006
03/23/01-
06/09/04
Lead
1.074
0.0062
Conca and
Wright, 2006;
Wright and
Conca, 2006
03/23/01-
06/09/04
Zinc
75.97
0.144
Conca and
Wright, 2006;
Wright and
Conca, 2006
03/23/01-
06/09/04
PH
4.69
6.69
Conca and
Wright, 2006;
Wright and
Conca, 2006
03/23/01-
06/09/04
Notes:
Averages calculated by EPA from temporal data in Table 1 in Wright and Conca, 2006 and converted
to mg/L; EPA used Vz the detection limit for values reported as below the detection limit to enable
calculations
Table 9-5: Average Upgradient and Within PRB Groundwater Concentrations - Nickel Rim Mine
Constituent
Upgradient
Concentration
Range3
Average
Concentration
Within PRBb
Source
Concentrations reported as dissolved in mg/L; pH in standard units
Iron
250-1,350
80
Benner et al., 1999; Doshi, 2006
Nickel
0.12-30
<0.1
Benner et al., 1999; Doshi, 2006
Sulfate
2,500-5,200
840
Benner et al., 1999; Doshi, 2006
Alkalinity
<1-60
2,300
Benner et al., 1999; Doshi, 2006
PH
2.8-5.9
6.7
Benner et al., 1999; Doshi, 2006
Notes:
a = Stated in Table 9 of Doshi, 2006 as "depth-integrated concentrations at Nickel Rim PRB, 1995-
1997"; however, it is not clear in Benner et al., 1999 (Doshi's cited reference) if these ranges are
maximum and minimum averages over the four nested wells for these three years or if they are a
range over depth for a single year. Examination of Figure 3 in Benner et al., 1999 suggests that these
are ranges over the four nested wells for only the 1996 sampling date.
b = The PRB comprised sand and organic zones; these data are from the organic zone. It is not clear
whether these data (stated in the text of Benner et al., 1999 as vertically-averaged (four nested
wells) within the PRB and reported in Table 9 of Doshi, 2006) are averages of four sampling dates
9-5
-------
Permeable Reactive Barriers
Table 9-5: Average Upgradient and Within PRB Groundwater Concentrations - Nickel Rim Mine
Constituent
Upgradient
Concentration
Range3
Average
Concentration
Within PRBb
Source
Concentrations reported as dissolvec
in mg/L; pH in standard units
(Benner et al., 1999: September 1995, June and September 1996, July 1997), or if they represent a
single sampling date. Examination of Figure 3 in Benner et al., 1999 suggests that these are averages
of vertically-averaged data from three sampling locations within the organic zone for the single
September 1996 sampling date.
On average, concentrations of cadmium and lead can be decreased to low ng/l concentrations in
groundwater treated by PRBs designed to stimulate sulfate reduction and subsequent precipitation of
metal sulfides (Table 9-4). Although not directly comparable (numerically), average effluent
concentrations of cadmium can be decreased by two orders of magnitude and lead can be decreased by
three orders of magnitude, similar to values observed in the comparison of corresponding influent and
effluent (Section 9.4.1). Unlike the corresponding influent and effluent concentrations, on average, zinc
concentration is decreased by two orders of magnitude (Table 9-4) versus three or four (Section 9.4.1).
On average, nickel concentration can be decreased to below 100 mg/L. Average sulfate concentration
within the PRB is an order of magnitude less than the upgradient concentration range. Coupled with the
decreased average concentrations of iron and nickel, this suggests the loss of sulfate is due to microbial
sulfate reduction and subsequent precipitation of the metals (Table 9-5). Alkalinity increased from
sulfate reduction (Benner et al., 2002).
9.4.3 Removal Efficiencies
Table 9-6 presents the average, maximum and minimum removal efficiencies over time (March 2001
through June 2004) for the PRB at the Success Mine and Mill site.
Table 9-6: Removal Efficiencies - Success Mine and Mill
Constituent
Average
Maximum
Minimum
Source
Removal
Removal
Removal
Efficiency
Efficiency
Efficiency
All concentrations reported as dissolved
Cadmium
99.64%
99.92%
98.06%
Conca and Wright, 2006;
Wright and Conca, 2006
Lead
99.48%
99.96%
95.36%
Conca and Wright, 2006;
Wright and Conca, 2006
Zinc
99.76%
100.00%
98.46%
Conca and Wright, 2006;
Wright and Conca, 2006
Notes:
EPA calculated removal efficiency from data provided in Table 1 of the source and used Vz the
detection limit in calculations for data reported as below detection
9-6
-------
Permeable Reactive Barriers
At the Success Mine and Mill site, average and maximum removal efficiencies for cadmium, lead and
zinc were above 99 percent (Table 9-6). The lowest removal efficiency was 95 percent for lead, whereas
the minimum removal efficiencies for cadmium and zinc were about the same at about 98 percent.
Doshi (2006) reported the iron removal efficiency as 68 to 95 percent, based on the range in iron
concentration in the upgradient zone compared to the average concentration within the organic zone of
the PRB (Benner et al., 1999). Benner et al. (2002) reported decreasing rates of sulfate and iron removal
occurring 38 months after installation of the PRB; however, the authors did not provide removal
efficiencies.
9.4.4 Flow Rates
An average velocity of 16 meters per year (Nickel Rim, Doshi, 2006) and an average flow of 19 liters per
minute (L/min) (Success Mine, Adams et al., 2006) were treated by the two PRBs. On average,
groundwater had a residence time within the PRBs ranging from 1 day (Success Mine, Adams et al.,
2006) to 90 days (Nickel Rim, Benner et al., 2002). Residence time ranged from 60 days at the center of
the PRB to 165 days at the top and bottom areas of the PRB at Nickel Rim (Benner et al., 2002). Future
case study comparisons may provide additional information on the typical flows or velocities of
groundwater treatable by a PRB.
9.5 Costs
At Success Mine, the cost of the PRB construction was approximately $500,000, including $35,000 for
100 tons of the apatite medium (Adams et al., 2006). At Nickel Rim, the PRB construction cost was
$30,000, including design, construction, materials and the reactive media (U.S. EPA, 2002; RTDF, 2000).
9.6 Lessons Learned
• Treatment media may become plugged or channeling may occur, which can reduce PRB
performance (Adams et al., 2006; Conca and Wright, 2006; Wright and Conca, 2006). The
reduction in hydraulic conductivity from plugging may require replacing material (Conca and
Wright, 2006; Wright and Conca, 2006) or air injections can be used to temporarily address the
issue (Adams et al., 2006; Doshi, 2006), or some other means of disaggregation.
• Plastic packing rings (Success Mine and Mill, Doshi, 2006) or other types of large-diameter
aggregate materials can be added to a media mixture to restore flow.
• Homogeneity and performance of PRBs can be improved by increasing the gravel fraction of the
media, choosing a different particle size distribution, or selecting a more reactive organic carbon
material, but costs of these enhancements should be weighed against the costs for replacing the
PRB more often or installing a thicker PRB (Benner et al., 2002).
• PRB design (e.g., size, hydraulic residence time) should account for site-specific, seasonal
temperature fluctuations that can lead to decreased treatment rates during cold periods. At the
Nickel Rime site, residence times greater than a year would eliminate temperature influences on
effluent concentrations (Benner et al, 2002).
9-7
-------
Permeable Reactive Barriers
9.7 References
9.7.1 Case Study References
Adams, B., Yancey, N., Conca, J., and Wright, J. 2006. PRB containing processed fish bones sequesters
metals from ground water. Technology News and Trends, 23:5-7.
Benner, S.G., D.W. Blowes, W.D. Gould, R.B. Herbert, Jr., and C.J. Ptacek. 1999. Geochemistry of a
permeable reactive barrier for metals and acid mine drainage. Environmental Science and Technology,
33:2793-2799.
Benner, S.G., Blowes, D.W., Ptacek, C.J., and Mayer, K.U. 2002. Rates of sulfate reduction and metal
sulfide precipitation in a permeable reactive barrier. Applied Geochemistry, 17(3), pp.301-320.
Conca, J.L. and J. Wright. 2006. An Apatite II permeable reactive barrier to remediate groundwater
containing Zn, Pb and Cd. Applied Geochemistry, 21:1288-1300.
Doshi, S.M. 2006. Bioremediation of acid mine drainage using sulfate-reducing bacteria. US
Environmental Protection Agency (U.S. EPA), Office of Solid Waste and Emergency Response and Office
of Superfund Remediation and Technology Innovation. 65 pp.
McCloskey, A.L., Stasney, B., Wright, J., Conca, J.L., Yancey, N., Lewis, N., and Joyce, H. 2006.
"Comparison of Apatite IITM Treatment Systems at Two Mines for Metals Removal." Paper presented at
the 7th International Conference on Acid Rock Drainage, St. Louis, MO, March 26-30, 2006. pp. 846-848.
Remediation Technologies Development Forum (RTDF), Permeable Reactive Barriers Action Team. 2000.
Permeable Reactive Barrier Installation Profiles, "Nickel Rim Mine Site, Sudbury, Ontario, Canada"
Accessed August 8, 2019. https://rtdf.clu-in.org/public/permbarr/prbsumms/profile.cfm?mid=41.
U.S. Environmental Protection Agency (U.S. EPA) Office of Solid Waste and Emergency Response. 2002.
Field applications of in situ remediation technologies: permeable reactive barriers. Washington, D.C.
https://clu-in.org/download/rtdf/fieldapp prb.pdf. 30 pp.
Wright, J. and Conca, J. 2006. "Remediation of Groundwater Contaminated with Zn, Pb and Cd Using a
Permeable Reactive Barrier with Apatite II. Paper presented at the 7th International Conference on Acid
Rock Drainage, St. Louis, MO, March 26-30, 2006. pp. 2514-2527.
9.7.2 General Capping References
Interstate Technology and Regulatory Council (ITRC). 2011. "Permeable Reactive Barrier: Technology
Update." https://www.itrcweb.org/Guidance/GetDocument?documentlD=69.
9-8
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10 Treatment Trains
A treatment train is a set of multiple technologies used in series to treat mining-influenced water (MIW).
Treatment trains can include technologies that are active, passive, semi-passive, or any combination.
MIW can contain a wide variety of inorganic constituents needing treatment, some of which are treated
best with technologies employing oxic mechanisms (e.g., aerobic wetlands, oxic limestone drains) and
some that are treated more effectively by anoxic mechanisms (e.g., biochemical reactors (BCRs),
anaerobic wetlands, anoxic limestone drains). Therefore, to treat all constituents of concern, multiple
treatment technologies (single or multi-step) are used in a treatment train. Some treatment systems
require a secondary step but are still considered a single treatment system. For example, aerobic
treatment is required for the effluent from an anaerobic treatment to increase oxygen content, remove
biochemical oxygen demand (BOD) and remove any residual gases produced by the anaerobic microbial
processes before the water can be released into a receiving water body. Settling ponds are an integral
part of treatment trains when the treatment includes processes that create precipitates (e.g., iron
oxyhydroxides) that need to be removed from the water prior to being released to the environment. In
these examples, the aerobic treatment or settling pond are not themselves considered add-on
treatment technologies forming a treatment train.
10.1 Case Studies Evaluated
This chapter provides an evaluation of case studies in which treatment trains were used to treat MIW.
The case studies evaluated were based on the screening criteria presented in the Section 1.1.1 and
include field pilot-scale and full-scale deployments at multiple mine sites in North America and Europe
(Table 10-1). This chapter includes full system treatment influent and effluent, rather than influent and
effluent for each successive technology within the treatment train; case studies that provided influent
and effluent for individual steps within a treatment train were discussed in previous technology-specific
chapters.
Nine of the treatment trains examined incorporated passive anaerobic BCRs with pre- and/or post-
treatment. In seven of these treatment trains, all components were passive. For the other two, one
treatment train consisted of three distinct systems included an active limestone-dosed (LD)2 pre-
treatment component, a limestone-free (LF) component, and an anoxic limestone drain (ALD) later
converted to a LD system (Wheal Jane Mine, Table 10-2), and the other included gravity-fed addition of
sodium hydroxide and ethanol prior to a settling pond (Leviathan, Table 10-2). Three of the treatment
trains included passive aerobic or anaerobic wetlands with additional treatments, such as limestone
filters or capping and one included neutralization and chemical precipitation via the use of a dispersed
alkaline substrate (DAS) in a system similar to an anoxic limestone drain or reducing and alkalinity-
producing system (RAPS), followed by post-treatment oxidation and settling. This chapter provides
considerations for constraints, treatability of contaminants, capability, technological and site-specific
requirements, costs, and lessons learned for treatment trains from evaluation of these case studies.
2 All references cited for the Wheal Jane case study indicated lime-dosed and lime-free, but it was indicated in
Whitehead and Prior (2005) that the pre-treatment was "lime dosing (calcium carbonate) to pH 5 (LD)", rather
than lime (calcium oxide or hydroxide); therefore, this report refers to these as limestone-dosed and limestone-
free.
10-1
-------
Table 10-1: Treatment Train Case Study Sites
Site Name
Technologies
Description
Study Type
Reference
Reference
and
Type
Location
Calliope
Passive
Two horizontal flow
Pilot scale
Wilmoth,
Report
Mine
anaerobic BCRs
BCRs: one below
2002*
Butte,
with passive
ground with pre-
Montana
pre-treatment
treatment (BCR II)
and one above
ground with pre-
treatment (BCR IV);
each unit contained
Bless et al.,
2008
Journal
paper
Nordwick et
al., 2006
Conference
paper
organic matter (cow
manure and straw)
and cobbles; pre-
treatment units
contained
additional organic
matter and
limestone.
Confidential
Passive
The BCR substrate
Pilot scale
Blumenstein
Conference
Mine,
anaerobic solid
consisted of wood
(technology
and Gusek,
paper
Montana
substrate BCR
followed by a
passive aerobic
polishing cell
and aeration
cell
chips, hay,
limestone, animal
manure and
crushed basalt. The
aerobic polishing
cell was a series of
vegetated ponds
with a large surface
area.
demonstration)
2009*
Copper
Passive
8,094 m2 (2-acre)
Pilot scale
Federal
FRTR case
Basin
anaerobic
anaerobic wetland
Remediation
study
Mining
wetlands
constructed with a
Technologies
summary
District,
followed by
geosynthetic clay
Roundtable
(online
Copper Hill,
passive aerobic
liner overlain with
(FRTR), 2007
document)
Tennessee
wetlands and
limestone rock
lime-enriched soil,
crushed limestone,
filter
hay, mushroom
compost and
planted with
cattails. After four
U.S. EPA,
2006b
Report
Faulkner and
Conference
years, two aerobic
Miller, 2002*
paper
cells and an aerobic
limestone rock filter
were added.
10-2
-------
Table 10-1: Treatment Train Case Study Sites
Site Name
and
Location
Technologies
Description
Study Type
Reference
Reference
Type
Dunka
Mine,
Babbitt,
Minnesota
Passive aerobic
wetlands with
passive pre-
and/or post-
treatment
limestone
Five unconnected
surface flow
wetland treatment
systems, each with
pre- and/or post-
treatment with
limestone. Each
system included a
series of soil berms,
covered in local
peat and peat
screenings, built to
control water levels
and maximize
contact between
the drainage and
the substrate.
Full scale
Eger and
Eger, 2005*
Conference
paper
Eger et al.,
1996
Conference
Paper
Eger et al.,
1998
Conference
paper
ITRC, 2010*
Report
Eger and
Beatty, 2013
Journal
paper
Force Crag
Cumbria,
United
Kingdom
Passive
anaerobic BCR,
solid substrate
and aerobic
wetland
Parallel vertical-flow
ponds containing
compost,
woodchips and
dried activated
sewage sludge,
followed by an
aerobic wetland.
Full scale
Jarvis et al.,
2015*
Conference
paper
Golden
Sunlight
Mine
Whitehall,
Montana
Settling pond
and passive
anaerobic BCR
Two-step process
using a settling
pond followed by a
BCR, which
contained crushed
limestone and
manure; water was
recirculated through
the system.
Pilot scale
Bless et al.,
2008*
Journal
paper
Leviathan
Mine
Alpine
County,
California
Semi-passive
chemical
addition, pre-
treatment
pond, passive
anaerobic
BCRs, settling
ponds and
System consisted of
a pre-treatment
pond (preceded by
gravity fed addition
of 25 percent
sodium hydroxide
and ethanol), two
BCRs in series, two
Full scale
Doshi, 2006
Report
U.S. EPA,
2006a*
Report
10-3
-------
Table 10-1: Treatment Train Case Study Sites
Site Name
Technologies
Description
Study Type
Reference
Reference
and
Type
Location
aeration
continuous flow-
channel
settling ponds, and
an aeration channel;
BCRs were lined
with high-density
polyethylene, river
rock and manure.
From November
2003 to mid-May
2004, the system
operated in gravity
flow mode; from
mid-May 2004
through 2005, the
system operated in
recirculating mode.
Monte
Passive natural
NFOL, followed by a
Pilot scale
Macfas et al.,
Journal
Romero
Fe-oxidizing
limestone-DAS tank,
2012a*
paper
Mine
lagoon (NFOL)
two aeration
Southweste
followed by
structures and
Macfas et al.,
Journal
rn Spain
passive
settling ponds, a
2012b
paper
limestone-DAS
second limestone-
Rotting et al.,
Journal
system
DAS tank followed
2008
paper
by two more
aeration structures
and settling ponds,
and then to a MgO-
DAStank. DAS tanks
filled with coarse
pine wood chips
mixed with
limestone sand.
Standard
Passive
System comprised a
Pilot scale
Gallagher et
Conference
Mine
anaerobic BCR
BCR followed by
al., 2012*
paper
Crested
with passive
aerobic polishing
Butte,
aerobic
cells; BCR contained
Reisman et
Conference
Colorado
polishing cells
hay, wood chips,
al., 2009*
paper
limestone and cow
manure.
Butler et al.,
Journal
2011
paper
Pilot scale
Report
10-4
-------
Table 10-1: Treatment Train Case Study Sites
Site Name
Technologies
Description
Study Type
Reference
Reference
and
Type
Location
Surething
Passive
System comprised
Nordwick
Mine
anaerobic
an anaerobic BCR
and Bless,
Helena,
BCRs,
followed by an
2008*
Montana
limestone drain
and passive
aerobic BCR
anoxic limestone
drain, followed by
another anaerobic
BCR, followed by an
aerobic BCR
containing
manganese-
oxidizing bacteria.
Tar Creek
Passive system
Oxidation pond
Full scale
Superfund
including
followed by parallel
Site
oxidation pond,
treatment trains
Oklahoma,
Kansas,
aerobic
wetlands,
consisting of surface
flow
Nairn et al.,
2009
Conference
Missouri
passive
anaerobic
wetlands/ponds,
vertical flow BCRs,
paper
BCRs, aeration
re-aeration ponds,
Nairn et al.,
Conference
ponds,
and horizontal-flow
2010a*
paper
limestone bed
limestone beds.
and wetland
Effluent from the
parallel trains are
recombined in a
polishing
wetland/pond prior
Nairn et al.,
2010b
Conference
paper
Nairn et al.,
2011*
Conference
paper
to final discharge.
Valzinco
Capping,
Reclamation
Full scale
Seal et al,
Conference
Mine
passive
occurred between
2008*
paper
Spotsylvania
limestone
2001 and 2002 and
County,
Virginia
drains and
constructed
wetlands
included the
removal and
isolation of tailings
in a covered pit,
installation of
several limestone
drains leading from
the pit and a series
of ponds and
wetlands.
Sobeck et al,
2008
Conference
paper
10-5
-------
Table 10-1: Treatment Train Case Study Sites
Site Name
and
Location
Technologies
Description
Study Type
Reference
Reference
Type
Wheal Jane
Active
Mine
limestone3 pre-
Cornwall,
treatment at
United
two
Kingdom
configurations,
passive aerobic
wetland,
passive
anaerobic BCR
and aerobic
rock filter
Three multi-cell
treatment systems
that utilized one of
three pre-treatment
methods to raise
pH: limestone3
dosing to pH 5.0
with calcium
carbonate (LD), an
anoxic limestone
drain (ALD,
modified to a LDa
system June 2000),
or a limestone a-free
system without pre-
treatment (LF). Pre-
treated drainage
passed to aerobic
reed bed wetlands
for iron and arsenic
removal. Next,
water flowed
through an
anaerobic cell (BCR)
for sulfate reduction
and metals removal.
The final stage was
an aerobic rock
filter, designed to
promote
manganese
removal. The
underground, lined
BCR contained a
mixture of 95%
softwood sawdust,
5% hay, and a small
quantity of cow
manure.
Pilot scale
Whitehead et
al., 2005*
Journal
paper
Whitehead
and Prior,
2005
Journal
paper
Johnson and
Hallberg,
2005*
Journal
paper
Notes:
* Primary source(s) of data for evaluation in this chapter
10-6
-------
Table 10-1: Treatment Train Case Study Sites
Site Name
and
Location
Technologies
Description
Study Type
Reference
Reference
Type
a = Whitehead and Prior (2005) specified that "lime dosing" was by using limestone rather than lime.
All the references for this case study site used the term "lime" when meaning limestone; this chapter
uses the term "limestone".
The treatment train at the Confidential Mine site is evaluated only qualitatively in this chapter because
the case study evaluated did not document successful treatment of constituents of concern with one
component of the treatment train - the aerobic polishing cell (Blumenstein and Gusek, 2009). The case
study did document successful treatment of thallium, selenium and nitrate with the BCR component of
the treatment train; this component of the case study is evaluated quantitatively in the BCRs chapter
(Section 3). BCR effluent water reported secondary constituents of concern - arsenic, iron and
manganese - that were not successfully treated with the aerobic polishing cell. The crushed basalt in the
BCR substrate was the suspected source of the unanticipated arsenic in the effluent; the basalt was not
characterized prior to its use in the BCR. The BCR effluent also had elevated levels of BOD as compared
to the influent, resulting from decomposition of the organic matter. Blumenstein and Gusek (2009)
noted that treatment of the secondary constituents of concern did not occur because BOD
concentrations did not decrease to levels below 30 to 50 mg/L before reaching the aerobic polishing cell.
10.2 Constraints
A primary constraint associated with treatment trains is the need for enough land area and suitable
topography to accommodate the treatment technologies. An additional constraint is the need to
determine the most effective combination and sequence of treatment technologies to treat MIW having
multiple constituents of concern, a process which may evolve over time (U.S. EPA, 2006a). Technologies
within the treatment train may have specific constraints; see Sections 3, 4, 5 and 7 for discussion on
constraints associated with BCRs, capping, neutralization and chemical precipitation, and constructed
wetlands, respectively.
10.3 Treatable Contaminants (All Configurations)
Treatment trains are capable of treating aluminum, arsenic, cadmium, chromium, cobalt, copper, iron,
lead, manganese, nickel, selenium, silicon, sulfate and zinc and raising pH (Wilmoth, 2002; Bless et al,
2008; Doshi, 2006; U.S. EPA, 2006a; Macfas et al., 2012a; Gallagher et al., 2012; Nordwick and Bless,
2008; Nairn et al., 2010a; Nairn et al., 2011; U.S. EPA, 2006a; Eger and Eger, 2005; Seal et al., 2008;
Jarvis et al., 2015; Whitehead et al., 2005; Johnson and Hallberg, 2005).
Treatment trains that incorporate an anaerobic BCR coupled with pre- and/or post-treatment with an
aerobic treatment technology (surface wetlands, ponds or lagoons) and/or active or passive limestone
treatment are able to raise pH and treat aluminum, arsenic, cadmium, chromium, cobalt, copper, iron,
lead, manganese, nickel, selenium, sulfate and zinc (Wilmoth, 2002; Bless et al, 2008; Doshi, 2006; U.S.
EPA, 2006a; Gallagher et al., 2012; Nordwick and Bless, 2008; Nairn et al., 2010a; Nairn et al., 2011;
Jarvis et al., 2015; Whitehead et al., 2005; Johnson and Hallberg, 2005).
10-7
-------
Treatment trains that incorporate passive aerobic or anaerobic constructed wetlands with capping
and/or passive pre- and/or post-treatment with limestone are able to raise pH and treat aluminum,
cadmium, cobalt, copper, iron, lead, manganese, nickel, sulfate and zinc (U.S. EPA, 2006a; Eger and Eger,
2005; Seal et al., 2008). Passive treatment using limestone, such as the dispersed alkaline precipitation
system, can treat aluminum, arsenic, copper, iron, lead, and silicon (Macfas et al., 2012a).
10.4 Capability-TreatmentTrains (All Configurations)
The capabilities of the three sub-categories of treatment trains are presented in sections below: passive
anaerobic BCR with active or passive pre-treatment and/or passive post-treatment (Section 10.5);
passive constructed wetlands (aerobic and/or aerobic) with passive pre- and/or post-treatment (Section
10.6); and alkaline precipitation with pre- and/or post-treatment (Section 10.7). Overall, treatment
trains can attain very low constituent concentrations, often below laboratory detection limits.
Treatment trains that incorporate an anaerobic BCR with passive pre- and/or post-treatment are
capable of treating influent concentrations less than 1 mg/L (cadmium, cobalt, chromium, nickel and
selenium; Tables 10-2 and 10-4) to over 80 mg/L (copper, iron, magnesium, manganese, sulfate, zinc;
Table 10-2 and 10-4). Treatment trains that incorporate anaerobic BCRs with passive pre- and/or post-
treatment are capable of decreasing influent concentrations of aluminum (1,740 mg/L), copper (81.4
mg/L) and lead (1.07 mg/L) by three or more orders of magnitude and can treat influent concentrations
of iron (198 mg/L), manganese (117 mg/L) and zinc (39.5 mg/L) by up to three orders of magnitude
(Table 10-2). The treatment train that incorporated an active limestone pre-treatment treated higher
concentrations, on average, of aluminum (about 50 mg/L) and zinc (>80 mg/L), as compared to the
treatment trains not having limestone addition. The treatment train that incorporated a semi-passive
sodium hydroxide and ethanol pre-treatment treated higher concentrations, on average, of chromium
(about 0.01 mg/L) and copper (about 0.8 mg/L), as compared to the treatment trains not having
chemical additions (Table 10-4).
Treatment trains incorporating passive constructed wetlands with capping and/or passive pre- and/or
post-treatment are able to increase pH and decrease influent concentrations of aluminum (1.4 mg/L),
cadmium (0.088 mg/L), copper (2.2 mg/L), iron (69.7 mg/L), lead (1.3 mg/L), manganese (2.1 mg/L),
nickel (0.037 mg/L), sulfate (1,400 mg/L)and zinc (27 mg/L) by an order of magnitude or more, as
indicated in Table 10-11 and Table 10-12.
On average, alkaline precipitation with pre- and/or post-treatment can decrease high concentrations
(>100 mg/L) of aluminum and iron to below detection limits. Lower concentrations of arsenic and lead
(<1 mg/L) and copper (5 mg/L) also can be decreased below detection limits in a treatment train
incorporating alkaline precipitation with pre- and/or post-treatment.
10.5 Capability - Anaerobic BCR with Pre- and/or Post-Treatment
10.5.1 Ranges of Applicability
Concentrations of metals tend to be inversely related to the pH, with higher concentrations associated
with a lower pH and lower concentrations associated with a higher pH. Tables 10-2 and 10-3,
respectively, show the ranges of applicability - the maximum influent concentration (minimum pH)
treated and corresponding effluent concentration attained, and the minimum influent concentration
(maximum pH) treated and corresponding effluent concentration attained. The tables include sites with
10-8
-------
passive pre-treatment and sites with active pre-treatment; data were not available for Tar Creek. The
ranges were determined by comparing values in Appendix E, Tables E-l, E-2, E-3, E-4, E-5, E-6, E-7, and
E-8. For each constituent, the minimum influent concentrations in the Appendix E tables are the lowest
concentrations reported that exceeded a case study's reported detection limit (DL).
Table 10-2: Maximum Influent and Corresponding Effluent Concentrations
Constituent
Maximum
Influent
Concentration
Corresponding
Effluent
Concentration
Mine
Source
Concentrations reported in mg/L; pH reported in standard units
Aluminum3
1,740
0.126
Golden Sunlight
Bless, 2008
Arsenic3
1.25
<0.01
Surething
Nordwick and Bless,
2008
Cadmium3
0.385
0.005
Surething
Nordwick and Bless,
2008
Chromiumb
0.0198
0.0132
Leviathan
U.S. EPA, 2006a
Copper3
81.4
0.001
Golden Sunlight
Bless, 2008
Iron3
198
2.62
Golden Sunlight
Bless, 2008
Lead3
1.07
0.001
Standard
Gallagher et al., 2012
Manganese3
117
67.8
Golden Sunlight
Bless, 2008
Nickel3
0.531
0.0189
Leviathan
U.S. EPA, 2006a
Seleniumb
0.0199
0.0108
Leviathan
U.S. EPA, 2006a
Sulfateb
1,510
1,160
Leviathan
U.S. EPA, 2006a
Zinc3
39.5
0.011
Golden Sunlight
Bless, 2008
PH
2.5
6.9
Surething
Nordwick and Bless,
2008
Notes:
Seven case studies provided influent and corresponding effluent data: Calliope (Table E-l), Force Crag
(Table E-2), Golden Sunlight (Table E-3), Leviathan (Table E-4), Standard (Table E-5), Surething (Table
E-6 and Table E-7), and Wheal Jane (Table E-8)
Chromium, nickel and selenium reported only for Leviathan Mine
a = dissolved
b = total
Table 10-3: Minimum Influent and Corresponding Effluent Concentrations
Constituent
Minimum
Influent
Concentration
Corresponding
Effluent
Concentration
Mine
Source
Concentrations reported in mg/L; pH reported in standard units
Aluminum3
2.4
0.0542
Calliope - BCR IV
Wilmoth, 2002
Arsenicb
0.0028
0.0024
Leviathan; Gravity mode
U.S. EPA,
2006a
10-9
-------
Table 10-3: Minimum Influent and Corresponding Effluent Concentrations
Constituent
Minimum
Influent
Concentration
Corresponding
Effluent
Concentration
Mine
Source
Concentrations reported in mg/L; pH reported in standard units
Cadmiumb
0.0004
<0.00023
Leviathan; Gravity mode
U.S. EPA,
2006a
Chromium3
0.0164
0.008
Leviathan; Gravity mode
U.S. EPA,
2006a
Copperb
0.011
0.0022
Standard
Gallagher et
al., 2012
Iron3
0.524
0.417
Calliope - BCR IV
Wilmoth, 2002
Lead3
0.0049
0.0029
Leviathan; Gravity Mode
U.S. EPA,
2006a
Manganese3
0.69
0.6
Calliope - BCR II
Wilmoth, 2002
Nickel3
0.478
0.0715
Leviathan; Gravity Mode
U.S. EPA,
2006a
Seleniumb
0.0096
0.0087
Leviathan; Gravity Mode
U.S. EPA,
2006a
Sulfate0
260
200
Wheal Jane; LF system
Johnson and
Hallberg, 2005
Zinc3
0.692
0.0147
Leviathan; Gravity Mode
U.S. EPA,
2006a
PH
7.52
7.21
Calliope - BCR II
Wilmoth, 2002
Notes:
Seven case studies provided influent and corresponding effluent data: Calliope (Table E-l), Force Crag
(Table E-2), Golden Sunlight (Table E-3), Leviathan (Table E-4), Standard (Table E-5), Surething (Table E-
6 and Table E-70), and Wheal Jane (Table
E-8)
Chromium, nickel and selenium reported only for Leviathan Mine
a = total
b = dissolved
c = total or dissolved not specified
LF = Limestone-free system without pre-treatment
Table 10-2 shows that treatment trains that incorporate anaerobic BCRs with pre- and/or post-
treatment technologies are able to decrease concentrations of many constituents by a minimum of
about one order of magnitude when starting with concentrations exceeding 0.5 mg/L; influent
concentrations of aluminum (1,740 mg/L), copper (81.4 mg/L) and lead (1.07 mg/L) decreased by three
or more orders of magnitude and influent concentrations of iron (198 mg/L), manganese (117 mg/L) and
zinc (39.5 mg/L) decreased by up to three orders of magnitude. Arsenic and cadmium influent
concentrations (1.25 mg/L and 0.385 mg/L) can be decreased by two orders of magnitude with
treatment.
Table 10-2 shows that a treatment train that incorporates anaerobic BCRs with semi-passive chemical
precipitation can decrease influent concentrations of chromium and selenium less than 0.02 mg/L at the
10-10
-------
single evaluated site. Each constituent was treated only to slightly lower concentrations on the same
order of magnitude (Table 10-2). The treatment train with semi-passive chemical precipitation was also
able to decrease nickel by one order of magnitude with a starting concentration of approximately 0.5
mg/L.
Table 10-3 shows that treatment trains that incorporate anaerobic BCRs with pre- and/or post-
treatment technologies are able to treat chromium, copper and nickel concentrations by more than one
order of magnitude and arsenic, cadmium, iron, lead, manganese, selenium and zinc by less than an
order of magnitude when concentrations are <1 mg/L. Treatment also occurs for aluminum when
beginning with an approximate concentration of 2 mg/L. A treatment train system that incorporates
anaerobic BCRs with pre- and/or post-treatment can also reduce cadmium influent (0.0004 mg/L) to
below the detection limit and was able to increase pH (Table 10-3).
The treatment train that incorporated the active limestone pre-treatment for two configurations (the LD
and ALD system after June 2000) reported data for a single sampling event; however, the highest
influent concentrations were lower than those in the other treatment trains and the lowest influent
concentrations were higher than those observed in the other treatment trains, so are not represented in
Tables 10-2 or 10-3. See Table E-8 in Appendix E for the range of applicability for the systems that
included an active limestone pre-treatment component (Johnson and Hallberg, 2005).
The treatment train that incorporated the semi-passive chemical pre-treatment reported treatment for
higher influent concentrations for chromium (0.0198 mg/L), nickel (0.531 mg/L) and sulfate (1,510 mg/L)
and lower influent concentrations for arsenic (0.0028 mg/L), cadmium (0.0004 mg/L), chromium (0.0164
mg/L), lead (0.0049 mg/L), nickel (0.478 mg/L) and zinc (0.692 mg/L) as compared to treatment trains
not having chemical additions (Tables 10-2 and 10-3).
10.5.2 Average Influent and Effluent Concentrations
Tables 10-4 and 10-5 present the highest and lowest average influent concentrations treated for each
constituent, respectively. Tables 10-6 and 10-7 list the highest and lowest average effluent
concentrations attained for each constituent, respectively. These values were determined by comparing
values in Appendix E, Tables E-9, E-10, E-ll, E-12, and E-13 derived from studies that reported this
information. It is important to note that average influent concentrations do not correspond directly with
the average effluent concentrations.
Table 10-4: Maximum Average Influent Concentration Treated
Constituent
Maximum
Average
Influent
Concentration
Average
Effluent
Concentration
Mine
Source
Concentrations reported in mg/L; pH reported in standard units
Aluminum3
48.6
3.3
Wheal Jane; ALD system
Whitehead et al.,
2005
Arsenic3
2.7
0.0
Wheal Jane; LD, ALD and
LF systems
Whitehead et al.,
2005
Cadmium3
0.1
0.0
Wheal Jane; LD, ALD and
LF systems
Whitehead et al.,
2005
10-11
-------
Table 10-4: Maximum Average Influent Concentration Treated
Constituent
Maximum
Average
Influent
Concentration
Average
Effluent
Concentration
Mine
Source
Concentrations reported in mg/L; pH reported in standard units
Chromium3
0.0122
0.0078
Leviathan; Gravity mode
U.S. EPA, 2006a
Cobaltb
0.066 ±0.008
0.007 ±
0.0004
Tar Creek
Nairn et al., 2011
Copper3
0.795
0.0046
Leviathan; Recirculation
mode
U.S. EPA, 2006a
lronb
177 ±2.33
0.57 ±0.207
Tar Creek
Nairn et al., 2011
Lead3
0.134
0.0038
Standard
Gallagher et al.,
2012
Magnesiumb
200 ±2.53
198 ± 7.49
Tar Creek
Nairn et al., 2011
Manganese3
21.4
12.2
Wheal Jane; ALD system
Whitehead et al.,
2005
Nickelb
0.945 ±0.015
0.035 ± 0.007
Tar Creek
Nairn et al., 2011
Selenium3
0.0139
0.0112
Leviathan; Gravity mode
U.S. EPA, 2006a
Sulfateb
2,239 ±26
2,047 ± 72
Tar Creek
Nairn et al., 2011
Zinc3
82.0
4.9
Wheal Jane; ALD system
Whitehead et al.,
2005
PH
3.9
6.6
Wheal Jane; ALD system
Whitehead et al.,
2005
Notes:
Five case studies provided average influent and effluent data: Calliope (Table E-9), Leviathan (Table
E-10), Standard (Table E-ll); Tar Creek (Table E-12) and Wheal Jane (Table E-13)
Whitehead et al., 2005 only reported one decimal place in Tables 1, 2 and 3
Cobalt and magnesium reported only for Tar Creek
Selenium reported only for Leviathan
a = dissolved
b = total
LD = Limestone-dosed pre-treatment
ALD = Anoxic limestone drain, modified to limestone-dosed system in June 2000 (Whitehead et al.,
2005)
LF = Limestone-free system without pre-treatment
10-12
-------
Table 10-5: Minimum Average Influent Concentration Treated
Constituent
Minimum
Average
Influent
Concentration
Average
Effluent
Concentration
Mine
Source
Concentrations reported in mg/L; pH reported in standard units
Aluminum3
0.094 ± 0.009
0.071 ±0.030
Tar Creek
Nairn et al.,
2011
Arsenicb
0.0074
0.0065
Leviathan; Recirculation
mode
U.S. EPA, 2006a
Cadmiumb
0.00060
<0.00020
Leviathan; Recirculation
mode
U.S. EPA, 2006a
Chromiumb
0.0111
0.0064
Leviathan; Recirculation
mode
U.S. EPA, 2006a
Cobalt3
0.066 ±0.008
0.007 ±0.0004
Tar Creek
Nairn et al.,
2011
Copperb
0.1
0.0028
Standard
Gallagher et al.,
2012
Iron3
11.2
0.54
Standard
Gallagher et al.,
2012
Leadb
0.0042
0.0025
Leviathan; Recirculation
mode
U.S. EPA, 2006a
Magnesium3
200 ± 2.53
198 ±7.49
Tar Creek
Nairn et al.,
2011
Manganese3
1.4
0.96
Calliope
Wilmoth, 2002
Nickelb
0.487
0.0655
Leviathan; Gravity mode
U.S. EPA, 2006a
Seleniumb
0.0115
0.0085
Leviathan; Recirculation
mode
U.S. EPA, 2006a
Sulfateb
281
122
Standard
Gallagher et al.,
2012
Zincb
0.715
0.0158
Leviathan; Gravity mode
U.S. EPA, 2006a
PH
6.05
7.49
Calliope - BCR II
Wilmoth, 2002
Notes:
Five case studies provided average influent and effluent data: Calliope (Table E-9), Leviathan (Table E-
10), Standard (Table E-ll); Tar Creek (Table E-12) and Wheal Jane (Table E-13)
Whitehead et al., 2005 only reported one decimal place in Tables 1, 2 and 3
Cobalt and magnesium reported only for Tar Creek
Selenium reported only for Leviathan
a = total
b = dissolved
LD = Limestone-dosed pre-treatment
ALD = Anoxic limestone drain, modified to limestone-dosed system in June 2000 (Whitehead et al., 2005)
LF = Limestone-free system without pre-treatment
10-13
-------
Table 10-6: Maximum Average Effluent Concentration Attained
Constituent
Maximum
Average
Effluent
Concentration
Average
Influent
Concentration
Mine
Source
Concentrations reported in mg/L; pH reported in standard units
Aluminum3
3.3
48.6
Wheal Jane; ALD system
Whitehead et al.,
2005
Arsenicb
0.007
0.5634
Calliope
Wilmoth, 2002
Cadmiumb
0.0039
0.0103
Calliope
Wilmoth, 2002
Chromium3
0.0078
0.0122
Leviathan; Gravity mode
U.S. EPA, 2006a
Cobaltb
0.007 ±
0.0004
0.066 ±0.008
Tar Creek
Nairn et al., 2011
Copper3
0.1
0.4
Wheal Jane; LF and LD systems
Whitehead et al.,
2005
Iron3
13.2
143.6
Wheal Jane; LD system
Whitehead et al.,
2005
Lead3
0.0038
0.134
Standard
Gallagher et al.,
2012
Magnesiumb
198 ± 7.49
200 ± 2.53
Tar Creek
Nairn et al., 2011
Manganese3
12.2
21.4
Wheal Jane; ALD system
Whitehead et al.,
2005
Nickel3
0.0697
0.529
Leviathan; Recirculation mode
U.S. EPA, 2006a
Selenium3
0.0112
0.0139
Leviathan; Gravity mode
U.S. EPA, 2006a
Sulfateb
2,047 ± 72
2,239 ±26
Tar Creek
Nairn et al., 2011
Zinc3
51.3
82
Wheal Jane; LF system
Whitehead et al.,
2005
PH
6.6
3.9
Wheal Jane; ALD system
Whitehead et al.,
2005
Notes:
Five case studies provided average influent and effluent data: Calliope (Table E-9), Leviathan (Table E-
10), Standard (Table E-ll); Tar Creek (Table E-12) and Wheal Jane (Table E-13)
Whitehead et al., 2005 only reported one decimal place in Tables 1, 2 and 3
Cobalt and magnesium reported only for Tar Creek
Selenium reported only for Leviathan
a = dissolved
b = total
LD = Limestone-dosed pre-treatment
ALD = Anoxic limestone drain, modified to a limestone-dosed system June 2000 (Whitehead et al.,
2005)
LF = Limestone-free system without pre-treatment
10-14
-------
Table 10-7: Minimum Average Effluent Concentration Attained
Constituent
Minimum
Average
Effluent
Concentration
Average
Influent
Concentration
Mine
Source
Concentrations reported in mg/L; pH reported in standard units
Aluminum3
0.0372
1.2229
Calliope - BCR IV
Wilmoth, 2002
Arsenicb
0.0
2.7
Wheal Jane; LF, ALD and LD
systems
Whitehead et al.,
2005
Cadmiumb
0.0
0.1
Wheal Jane; LF, ALD and LD
systems
Whitehead et al.,
2005
Chromiumb
0.0064
0.0111
Leviathan; Recirculation mode
U.S. EPA, 2006a
Cobalt3
0.007 ±
0.0004
0.066 ±0.008
Tar Creek
Nairn et al., 2011
Copperb
0.0
0.4
Wheal Jane; ALD system
Whitehead et al.,
2005
Iron3
0.57 ±0.207
177 ± 2.33
Tar Creek
Nairn et al., 2011
Leadb
0.0025
0.0042
Leviathan; Recirculation mode
U.S. EPA, 2006a
Magnesium3
198 ± 7.49
200 ± 2.53
Tar Creek
Nairn et al., 2011
Manganese3
0.786067
1.4581
Calliope - BCR II
Wilmoth, 2002
Nickel3
0.035 ± 0.007
0.945 ± 0.015
Tar Creek
Nairn et al., 2011
Seleniumb
0.0085
0.0115
Leviathan; Recirculation mode
U.S. EPA, 2006a
Sulfateb
122
281
Standard
Gallagher et al.,
2012
Zincb
0.0089
0.776
Leviathan; Recirculation mode
U.S. EPA, 2006a
PH
7.74
5.84
Calliope-BCR IV
Wilmoth, 2002
Notes:
Five case studies provided average influent and effluent data: Calliope (Table E-9), Leviathan (Table
E-10), Standard (Table E-ll); Tar Creek (Table E-12) and Wheal Jane (Table E-13)
Whitehead et al., 2005 only reported one decimal place in Tables 1, 2 and 3
Cobalt and magnesium reported only for Tar Creek
Selenium reported only for Leviathan
a = total
b = dissolved
LD = Limestone-dosed pre-treatment
ALD = Anoxic limestone drain, modified to a limestone-dosed system June 2000 (Whitehead et al.,
2005)
LF = Limestone-free system without pre-treatment
The treatment train that incorporated an active limestone pre-treatment (Wheal Jane) for a portion of
the treatment period (ALD system was converted to LD after June 2000) was capable of treating higher
concentrations, on average, of aluminum (about 50 mg/L) and zinc (>80 mg/L) and raising pH from 3.9 to
6.6 (Table 10-4). In contrast, the LD system in the treatment train did not treat aluminum, on average
(Table E-13). The lowest influent concentrations were not observed in the single case study evaluated
10-15
-------
with limestone pre-treatment (LD system and ALD system after June 2000), which generally exhibited
higher average influent concentrations than at other sites that reported average influent and effluent
(Table 10-5). Treatment of manganese occurred in the treatment train with active pre-treatment for a
portion of the treatment period (ALD system) with maximum average influent and average effluent
concentrations on the same order of magnitude (21.4 mg/L, influent to 12.2 mg/L, effluent). The
maximum average effluent concentrations for aluminum (ALD; 3.3 mg/L), copper (LD; 0.1 mg/L), iron
(LD; 13.2 mg/L), and manganese (ALD; 12.2 mg/L) were observed in the single case study evaluated that
incorporated active limestone pre-treatment (Table 10-6). Table 10-7 shows that at the single case study
evaluated that incorporated anaerobic BCRs with limestone pre-treatment decreased concentrations of
arsenic, cadmium, and copper concentrations to 0.0, although the data were reported to only one
decimal place (Whitehead et al., 2005). It should also be noted that the same influent and effluent
concentrations of arsenic, cadmium and copper were reported for all three configurations, one of which
(Wheal Jane limestone-free configuration) did not contain an active limestone pre-treatment
component.
The treatment train that incorporates anaerobic BCRs with semi-passive chemical precipitation pre-
treatment (Leviathan) is capable of treating influent concentrations of chromium (0.0111 - 0.0122
mg/L), copper (0.795 mg/L), nickel (0.487 mg/L), selenium (0.0115 - 0.0139 mg/L) and zinc (0.715 mg/L)
by at least one order of magnitude. Influent concentrations of arsenic (0.0074 mg/L), lead (0.0042 mg/L)
and cadmium (0.00060 mg/L) were treated but effluent concentrations were within the same order of
magnitude (Table 10-4 and 10-5).
Treatment trains that incorporate anaerobic BCRs and pre- and/or post-treatment technologies are
capable of treating by more than one order of magnitude the highest average influent concentrations of
chromium, cobalt, copper, iron, lead and nickel and the lowest average influent concentrations of
cadmium, chromium, cobalt, copper, iron, nickel, selenium and zinc (Table 10-4 and 10-5). Tables 10-4
and 10-5 also show that, on average, there is treatment of less than an order of magnitude of arsenic at
<0.01 mg/L and manganese at 1.4 mg/L with average effluent concentrations for arsenic and
manganese. The highest reported average effluent concentrations for treatment trains with anaerobic
BCRs and passive pre- and/or post-treatment were below 0.01 mg/L for arsenic, cadmium, cobalt and
lead and below 0.1 mg/L for nickel and selenium (Table 10-6). The lowest average effluent
concentrations were below 0.01 mg/L for chromium, cobalt, lead, selenium and zinc and below 1.0 mg/L
for aluminum, iron and manganese (Table 10-7). Regardless of the type of pre- and/or post-treatment
technologies used in the treatment trains having BCRs as a primary treatment, all treatment trains were
able to increase pH of the water treated.
10.5.3 Removal Efficiency
The maximum and minimum removal efficiencies in Tables 10-8 and 10-9, respectively, were
determined by comparing values in Appendix E, Tables E-14, E-15, E-16, E-17, E-18, E-19, E-20, E-21 and
E-22. The comparison was done on the same sample type - total or dissolved.
Table 10-8: Maximum Removal Efficiencies
Constituent
Maximum Removal
Efficiency
Mine
Source
Aluminum3
99.99%
Golden Sunlight
Bless, 2008
10-16
-------
Table 10-8: Maximum Removal Efficiencies
Constituent
Maximum Removal
Efficiency
Mine
Source
Arsenic3
>92.13%
Surething
Nordwick and Bless,
2008
Cadmium3
>99.96%
Surething
Nordwick and Bless,
2008
Chromium3
84.8%
Leviathan - Recirculation mode
U.S. EPA, 2006a
Copper3
99.99%
Golden Sunlight
Bless, 2008
Iron3
>99.91%
Surething
Nordwick and Bless,
2008
Lead3
97.35%
Surething
Nordwick and Bless,
2008
Manganese3
99.86%
Surething
Nordwick and Bless,
2008
Nickelb
98.8%
Tar Creek
Nairn et al., 2010b
Seleniumb
57.4%
Leviathan - Gravity mode
U.S. EPA, 2006a
Sulfate15
37.29%
Calliope - BCR IV
Wilmoth, 2002
Zinc3
>99.97%
Surething
Nordwick and Bless,
2008
Notes:
Nine case studies provided removal efficiencies or influent and effluent data from which EPA
calculated removal efficiencies: Calliope (Table E-14), Golden Sunlight (Table E-15), Leviathan (Tables
E-16 and E-17), Standard (Table E-18), Surething (Table E-19), Tar Creek (Table E-20), and Wheal Jane
(Tables E-21 and E-22)
Chromium and selenium only reported for Leviathan
Maximum removal efficiencies are the higher percentage of average and maximum removal
efficiencies provided in Appendix E, Tables E-3, E-9, E-ll, E-13, E-18, E-21, E-23, E-26 and E-28
a = dissolved
b = total
Table 10-9: Minimum Removal Efficiencies
Constituent
Minimum Removal
Efficiency
Mine
Source
Aluminum3
-430.81%
Calliope - BCR II
Wilmoth, 2002
Arsenic3
-839.29%
Calliope-BCR IV
Wilmoth, 2002
Cadmium3
8.11%
Calliope-BCR IV
Wilmoth, 2002
Chromiumb
21.2%
Leviathan - Recirc. mode
U.S. EPA, 2006a
Copper3
-233.33%
Calliope - BCR II
Wilmoth, 2002
Iron3
-10192.68%
Calliope - BCR II
Wilmoth, 2002
Lead3
9.7%
Leviathan - Recirc. mode
U.S. EPA, 2006a
Manganese3
-185.71%
Calliope - BCR II
Wilmoth, 2002
Nickelb
71.0%
Leviathan - Recirc. mode
U.S. EPA, 2006a
Seleniumb
9.4%
Leviathan - Gravity mode
U.S. EPA, 2006a
10-17
-------
Table 10-9: Minimum Removal Efficiencies
Constituent
Minimum Removal
Mine
Source
Efficiency
Sulfate3
-167.21%
Calliope-BCR IV
Wilmoth, 2002
Zinca
25.48%
Calliope - BCR II
Wilmoth, 2002
Notes:
Nine case studies provided removal efficiencies or influent and effluent data from which EPA
calculated removal efficiencies: Calliope (Table E-14), Golden Sunlight (Table E-15), Leviathan
(Tables E-16 and E-17), Standard (Table E-18), Surething (Table E-19), Tar Creek (Table E-20) and
Wheal Jane (Tables E-21 and E-22)
Chromium and selenium only reported for Leviathan
Minimum removal efficiencies are the lower percentage of average and minimum removal
efficiencies provided in Appendix E, Tables E-14, E-15, E-16, E-17, E-18, E-19, E-20, E-21 and E-22
a = total
b = dissolved LF = Limestone-free system without pre-treatment
Table 10-8 shows that treatment trains that incorporate anaerobic BCRs and pre- and/or post-treatment
can attain greater than 98 percent removal efficiency for aluminum, cadmium, copper, iron, manganese,
nickel and zinc. Treatment trains that incorporate anaerobic BCRs and pre- and/or post-treatment can
also attain removal efficiencies of approximately 92 percent, 85 percent, 97 percent, 57 percent and 37
percent, for arsenic, chromium, lead, selenium and sulfate, respectively.
As shown by comparing data in Tables 10-8 and 10-9, removal efficiencies from treatment trains that
incorporate anaerobic BCRs and pre- and/or post-treatment span a wide range for most constituents.
When comparing constituents where this information was available from more than one case study, the
widest range (~10,293 percent) occurs for iron, while the smallest range (~28 percent) occurs for nickel.
The negative removal efficiencies for multiple constituents in Table 10-9 were from a single case study in
which EPA calculated the sampling date specific removal efficiencies from the corresponding influent
and effluent data provided in the study (Wilmoth, 2002). Some sampling dates had concentrations of
aluminum, arsenic, copper, iron, manganese and sulfate in the effluent samples that were higher than
the corresponding influent samples used for calculating removal efficiencies. Removal efficiencies for a
treatment train that incorporates anaerobic BCR and semi-passive chemical precipitation range from
21.2 percent to 84.8 percent for chromium and 9.4 percent to 57.4 percent for selenium.
10.5.4 Flow Rates
Flow rates for treatment trains that incorporate anaerobic BCRs and active or passive pre- and/or post-
treatment are provided in Table 10-10. In the absence of operational flow rates and where available,
design flow rates were included.
Table 10-10: Influent Flow Rates
Mine
Flow Rate (L/min)
Source
Notes
Passive Pre-treatment and Passive Post-Treatment
Calliope
3.8 with four months at 7.6
Wilmoth, 2002
Operational flow rate
10-18
-------
Table 10-10: Influent Flow Rates
Mine
Flow Rate (L/min)
Source
Notes
Passive Pre-treatment and Passive Post-Treatment
Force Crag
360
Jarvis et al., 2015
Design flow rate; influent
flow rate 510 - 1,464
L/min; average flow rate
888 L/min
Golden Sunlight
11.4
Bless, 2008
Design flow rate; BCR
operated at 7.6 L/min
Leviathan
31.8 (gravity-flow mode)
34.2 (recirculation mode)
Doshi, 2006
Reported for 2003-2005
Standard
3.8
Gallagher et al.,
2012
Design flow rate
Surething
7.6
Doshi, 2006
Design flow rate; actual
discharge reached peaks of
38 L/min
Tar Creek
1,000
Nairn et al, 2010a
Design flow rate
Active Pre-treatment and Passive Post-Treatment
Wheal Jane
12-24
Whitehead et al.,
2005
Operational flow rate
range
Flow rates for treatment trains incorporating anaerobic BCRs with passive pre- and/or post-treatment
range from 3.8 to 1,000 liters per minute (L/min). Flow rates for the treatment train consisting of an
anaerobic BCR with an active pre-treatment component ranged from 12 to 24 L/min.
10.6 Capability - Constructed Wetlands with Capping and/or Pre- or Post-Treatment
10.6.1 Ranges of Applicability
No case studies were examined where an influent or pre-treatment concentration provided for any
constituent corresponded directly to an effluent or post-treatment concentration. Only two examined
case studies provided non-averaged pre-treatment and post-treatment data and those data are included
in this section to address range of applicability.
Table 10-11 shows the range in concentrations of constituents in stream water below the Valzinco site
prior to reclamation, which included capping of mining wastes, and the concentrations of those
constituents in the stream water six years after completion of reclamation (Seal et al., 2008) from data
in Appendix E, Table E-23. Table 10-12 shows the maximum pre-treatment and maximum post-
treatment concentrations observed over 2004-2006 for constituents at Copper Basin (U.S. EPA, 2006a)
from data in Appendix E, Table E-24.
10-19
-------
Table 10-11: Pre-Treatment Concentration Range and Post-Treatment Concentration in Stream
Water Downstream from Valzinco
Constituent
Pre-Treatment Concentration
Range
Post-Treatment Concentration
Concentrations reported in mg/l as dissolved; pH reported in standard units
Aluminum
0.60-19.5
0.051
Cadmium
0.0032-0.088
0.00091
Copper
0.049-2.2
0.0097
Iron
5.0-69.7
1.01
Lead
0.170-1.3
0.0016
Manganese
0.410-2.1
1.12
Nickel
0.002-0.037
0.0023
Sulfate
27 -1,400
38.0
Zinc
1.9-27
1.32
PH
2.6-4.0
5.1
Notes:
Data from Table 1 in Seal et al., 2008; pre-reclamation and post-reclamation samples collected at the
same location; pre-reclamation data collected 1998 - 2001; post-reclamation data collected June
2007
Table 10-12: Maximum Pre-Treatment and Post-Treatment Concentrations for the Copper Basin
Site
Constituent
Maximum Pre-Treatment
Concentration
Maximum Post-Treatment
Concentration
Concentrations reported in mg/l as total, except manganese is reported as dissolved; pH reported in
standard units; acidity reported in mg/l as CaC03
Aluminum
1.423
0.055
Copper
0.197
0.017
Iron
0.211
0.133
Manganese
1.148
0.294
Sulfate
110
104
Zinc
0.640
0.197
pH
4.28
7.16
Net acidity
37
< 1
Notes:
Data from Table 1 of U.S. EPA, 2006 represents the maximum values observed between 2004 and
2006.
10-20
-------
Treatment trains incorporating passive constructed wetlands with capping and/or passive pre- or post-
treatment are able to increase pH and decrease concentrations of aluminum, cadmium, copper, iron,
lead, manganese, nickel, sulfate and zinc by an order of magnitude or more, as indicated in Table 10-11
and Table 10-12. At lower pre-treatment concentrations of nickel, sulfate, and zinc, however, post-
treatment concentrations are similar or on the same order of magnitude.
The treatment train at Copper Basin was able to achieve a maximum pH of 7.16 over the 3 years of study
and decrease acidity to less than 1 mg/l as CaC03, whereas the pH of effluent from the treatment train
at Valzinco was somewhat acidic (pH 5.1) after 6 years of treatment. The difference in observed
achievable pH may be due to the differences in treatment duration or perhaps to the differences in
concentrations of constituents contributing to pH, where maximum pre-treatment constituent
concentrations at Valzinco were higher (see Tables 10-11 and 10-12).
10.6.2 Average Pre- and Post-Treatment Concentrations
Average concentrations were reported for four independent wetland treatment trains in a single case
study site (Dunka Mine). Note, an additional wetland was operated at the Dunka Mine site but was
independent of other components and is captured in the Constructed Wetlands chapter, Section 7.
Tables 10-13 and 10-14 list the highest and lowest average pre-treatment concentrations for each
constituent, respectively. Tables 10-15 and 10-16 list the highest and lowest average post-treatment
concentrations attained for each constituent, respectively. Values in Tables 10-13 through 10-16 were
determined from Table E-25 in Appendix E. It is important to note that the average pre-treatment
concentrations do not correspond directly with the average post-treatment concentrations.
Table 10-13: Maximum Average Pre-Treatment Concentration Treated
Constituent
Maximum
Average Pre-
Treatment
Concentration
Average Post-
Treatment
Concentration
Mine-Wetland
Source(s)
Notes
Concentrations reported in mg/L, total or dissolved not stated; pH reported in standard units
Cobalt
0.13
0.04
Dunka - Seep 1
Eger and
Eger, 2005
1995 -1997
Copper
0.37
0.11
Dunka - Seep X
Eger and
Eger, 2005
1999 - 2004
Nickel
6.64
3.27
Dunka - Seep 1
Eger and
Eger, 2005
1995 -1997
Zinc
0.928
0.385
Dunka - Seep 1
Eger and
Eger, 2005
1995 -1997
PH
6.94
7.23
Dunka - Seep 1
Eger and
Eger, 2005
1995 -1997
10-21
-------
Table 10-14: Minimum Average Pre-Treatment Concentration Treated
Constituent
Minimum
Average Pre-
Treatment
Concentration
Average Post-
Treatment
Concentration
Mine-
Wetland
Source(s)
Notes
Concentrations reported in mg/L, total or dissolved not stated; pH reported in standard units
Cobalt
0.015
0.006
Dunka - EM8
ITRC, 2010a
Jan. to Sept.
1998
Copper
0.026
0.009
Dunka - EM8
Eger and
Eger, 2005
1999 - 2004
Nickel
1.5
0.61
Dunka - Seep X
Eger and
Eger, 2005
1995 -1997
Zinc
0.05
0.008; <0.001;
0.006
Dunka -
W2D/3D
Eger and
Eger, 2005
Minimum
average
influent
corresponds
to effluent
for 1992-
1994; 1996
-1998;and
1999 - 2004
PH
7.41
7.3
Dunka - EM8
Eger and
Eger, 2005
1999 - 2004
Table 10-15: Maximum Average Post-Treatment Concentration Attained
Constituent
Maximum
Average Post-
Treatment
Concentration
Average Pre-
Treatment
Concentration
Mine-Wetland
Source(s)
Notes
Concentrations reported in mg/L, total or dissolved not stated; pH reported in standard units
Cobalt
0.04
0.13
Dunka - Seep 1
Eger and
Eger, 2005
1995 -1997
Copper
0.11
0.37
Dunka - Seep X
Eger and
Eger, 2005
1999-2004
Nickel
3.27
6.64
Dunka - Seep 1
Eger and
Eger, 2005
1995 -1997
Zinc
0.385
0.928
Dunka - Seep 1
Eger and
Eger, 2005
1999-2004
PH
7
7
Dunka-W2D/3D
Eger and
Eger, 2005
1992-1994,
1996-1998,
1992-1997
10-22
-------
Table 10-16: Minimum Average Post-Treatment Concentration Attained
Constituent
Minimum
Average Post-
Treatment
Concentration
Average Pre-
Treatment
Concentration
Mine-Wetland
Source(s)
Notes
Concentrations reported in mg/L, total or dissolved not stated; pH reported in standard units
Cobalt
0.002
0.02
Dunka-W2D/3D
ITRC, 2010a
1992-1997
Copper
<0.001
0.05
Dunka-W2D/3D
Eger and Eger,
2005
1996 -1998
Nickel
0.036
1.9
Dunka-W2D/3D
Eger and Eger,
2005
1999 - 2004
Zinc
<0.001
0.05
Dunka-W2D/3D
Eger and Eger,
2005
1996 -1998
PH
7.4
7
Dunka-W2D/3D
Eger and Eger,
2005
1999 - 2004
Tables 10-13 through 10-16 suggest that, on average, cobalt, copper and zinc concentrations of less than
1 mg/L, and nickel concentrations ranging from 1.5 to 6.6 mg/L, are able to be decreased by treatment
trains incorporating wetland treatment. Generally, the average post-treatment concentrations are at
least one order of magnitude lower than the average pre-treatment concentrations for each
constituent. Wetland treatment can achieve average post-treatment concentrations of below detection
limits for copper and zinc. Influent to the wetland treatment trains in the single case study had average
pH values of near neutral, and these were maintained in the effluent.
10.6.3 Removal Efficiency
Removal efficiencies were reported for four independent wetland treatment trains at a single case study
(Dunka). Tables 10-17 and 10-18 present the maximum and minimum average removal efficiencies,
respectively, extracted from average removal efficiencies presented in Appendix E, Table E-26 for the
four wetlands.
Table 10-17: Maximum Average Removal Efficiencies
Constituent
Maximum
Average
Removal
Efficiency
Mine - Wetland
Source
Notes
Total or dissolved not stated
Cobalt
90%
Dunka-W2D/3D
Eger and Eger,
2005
Calculated based on
averages presented for
1992-1994 and 1992-
1997
Copper
99%
Dunka-W2D/3D
Eger and Eger,
2005
Calculated based on
averages presented for
1996-1998
10-23
-------
Table 10-17: Maximum Average Removal Efficiencies
Constituent
Maximum
Average
Removal
Efficiency
Mine - Wetland
Source
Notes
Nickel
98%
Dunka-W2D/3D
Eger and Eger,
2005
Calculated based on
averages presented for
1999-2004
Zinc
99%
Dunka-W2D/3D
Eger and Eger,
2005
Calculated based on
averages presented for
1996-1998
Notes:
One case study - Dunka - provided average influent and effluent data for four separate wetland
treatment trains: Seep 1, Seep X, W2D/3D, EM8
Table 10-18: Minimum Average Removal Efficiencies
Constituent
Minimum
Average
Removal
Efficiency
Mine -
Wetland
Source
Notes
Total or dissolved not stated
Cobalt
60%
Dunka - EM8
ITRC, 2010a
Calculated based on
averages presented for
Jan. to Sept. 1998
Copper
62%
Dunka - EM8
ITRC, 2010a
Calculated based on
averages presented for
Jan. to Sept. 1998
Nickel
33%
Dunka - EM8
Eger and Eger,
2005
Calculated based on
averages presented for
1999-2004
Zinc
36%
Dunka - Seep X
Eger and Eger,
2005
Calculated based on
averages presented for
1999-2004
Notes:
One case study - Dunka - provided average influent and effluent data for four separate wetland
treatment trains: Seep 1, Seep X, W2D/3D, EM8
Table 10-17 shows that treatment trains that incorporate constructed wetlands with pre- or post-
treatment can attain 98 percent or greater removal efficiency for copper, nickel and zinc and 90 percent
for cobalt. The minimum average removal efficiencies range from 33 percent (nickel) to 62 percent
(copper). Eger and Eger, 2005 indicated that wetland treatment train W2D/3D was built with sufficient
area to treat the original flow, whereas the available area for wetland treatment train EM8 was too
small and Seep X, while properly sized, had a smaller effective treatment area that was smaller than the
total size of the system.
10-24
-------
10.6.4 Flow Rates
Average influent flow treatable with passive treatment trains that incorporate constructed wetlands
with pre- and post-treatment ranges between 20 L/min and 400 L/min at Dunka (Eger and Eger, 2005;
ITRC, 2010 - Dunka) to 342 L/min to 4,200 L/min at Valzinco (Seal et al., 2008) (Appendix E, Table E-27).
Future case study comparisons may provide additional information on the flow capabilities of the
passive treatment trains that incorporate constructed wetlands as a primary component of treatment.
10.7 Capability - Alkaline Precipitation with Pre- and/or Post-Treatment
10.7.1 Ranges of Applicability
No non-averaged corresponding influent and effluent concentrations of constituents treated were
presented in the single case study evaluated; therefore, the range of applicability cannot be determined.
10.7.2 Average Pre- and Post-Treatment Concentrations
Average concentrations were reported for the alkaline precipitation with pre- and post-treatment at a
single case study (Monte Romero Mine) (Table 10-19 and E-28). On average, alkaline precipitation with
pre- and post-treatment is able to decrease high concentrations (>100 mg/L) of aluminum and iron to
below detection limits. Lower concentrations of arsenic and lead (<1 mg/L) and copper (5 mg/L) also
were decreased to below detection limits. Manganese, magnesium, calcium, potassium and sulfate
increased, on average. Increases in concentrations of calcium and magnesium are expected in effluent
from these types of treatment systems from dissolution of the limestone (CaC03) that also typically has
magnesium salts associated with it. Although not stated in the study, potassium may have originated
from the pine wood shavings. The pre-existing iron terraces, cascades, and lagoon (NFOL) and two DAS
treatment tanks were able to increase pH, on average, to 6.6 (Table 10-19) and to remove 1,350 mg/l of
net acidity as CaC03 from the mine shaft water having 1,800 mg/l net acidity as CaC03.
Table 10-19: Average Influent and Effluent Concentrations - Monte Romero Mine
Constituent
Average Influent
Concentration
Average Effluent
Concentration
All concentrations reported as total
'n mg/L; pH reported in standard units
Aluminum
100
<0.2
Arsenic
0.507
<0.002
Calcium
250
850
Copper
5
<0.005
Iron
275
<0.2
Lead
0.174
<0.001
Magnesium
255
386
Manganese
18
19
Potassium
5
7
Silicon
37
11
Sulfate
3,430
3,770
Zinc
440
414
PH
3
6.6
Eh
508
341
10-25
-------
Table 10-19: Average Influent and Effluent Concentrations - Monte Romero Mine
Constituent
Average Influent
Average Effluent
Concentration
Concentration
Notes:
Source: Macfas et al., 2012a
Influent represents untreated water in the "Shaft" samples
Effluent is the overall system effluent, represented by "T2 Out"
samples
Influent and effluent averages from Table 1 and represent monitoring from April to
September 2008
10.7.3 Removal Efficiency
Removal efficiencies were reported in the single case study (Table E-29 in Appendix E). Treatment trains
that incorporate alkaline precipitation with pre- and post-treatment can attain 99 percent or greater
removal efficiency for aluminum, arsenic, copper, iron and lead and approximately 70 percent removal
efficiency for silicon. The removal efficiency for zinc is much lower, at about 6 percent (Table E-29 in
Appendix E). Based on the single study, alkaline precipitation with pre- and post-treatment was not able
to remove manganese or sulfate. As seen with the average effluent concentrations, negative removal
efficiencies for calcium, magnesium, and potassium indicate dissolution of the limestone or originate
from other substrate materials as the water is treated.
10.7.4 Flow Rates
The single case study of a treatment train incorporating alkaline precipitation with pre- and post-
treatment reported an influent flow rate of 90 L/min with an operational flow rate in the post-treatment
lagoon of 1 L/min (Table E-27 in Appendix E).
10.8 Costs
Construction of treatment train systems range from $75,000 to about $1.7 million (Eger et al., 1998; U.S.
EPA, 2006a; Nairn et al., 2009; ITRC, 2010; Doshi, 2006). Operation and maintenance (O&M) of these
systems are approximately $100,000 per year (Doshi, 2006).
• Construction of treatment trains with wetlands as the primary component range from $75,000
to $1 million (Eger et al., 1998; ITRC, 2010; U.S. EPA, 2006a). O&M costs were not available.
• Construction of treatment trains with BCRs range from $836,600 to $1.7 million (U.S. EPA,
2006a; Nairn et al., 2009; Doshi, 2006). O&M costs for these systems are approximately
$100,000 per year (Doshi, 2006). Costs were not provided for the treatment trains with BCR and
active limestone pre-treatment.
Construction or O&M costs were not provided for treatment trains with alkaline precipitation.
10.9 Lessons Learned
• Microbially-mediated processes in passive treatment systems operate more effectively when
the acidity of the influent water is decreased through use of a settling pond (Bless et al., 2008)
or bioreactors are given time to develop stable and healthy populations before being exposed to
the water to be treated (Doshi, 2006).
10-26
-------
• Although concentrations of constituents may be decreased by passive treatment trains,
concentrations attained may remain above chronic or acute aquatic toxicity criteria (Seal et al.,
2008).
• The collection and treatment of rainwater within treatment train consisting of aerobic cells and
a compost bioreactor should be avoided (Doshi, 2006).
• Passive treatment trains using anaerobic BCRs should include technologies such as rock filters,
ponds or aerobic wetlands to remove manganese, bacteria and sulfide, and to restore dissolved
oxygen prior to discharge (Butler et al., 2011; Doshi, 2006).
10.10 References
10.10.1 Case Study References
Bless, D., Park, B., Nordwick, S., Zaluski, M., Joyce, H., Hiebert, R., and Clavelot, C. 2008. Operational
Lessons Learned During Bioreactor Demonstrations for Acid Rock Drainage Treatment. Mine Water and
the Environment, 27:241-250.
Blumenstein, E.P. and Gusek, J.J. 2009. Overcoming the Obstacles of Operating a Biochemical Reactor
and Aerobic Polishing Cell Year Round in Central Montana. Paper presented at the 2009 National
Meeting of the American Society of Mining and Reclamation, Billings, MT, May 30 - June 5, 2009. pp.
109-129. R.I. Barnhisel (Ed.). Published by ASMR, Lexington, KY.
Butler, B.A., Smith, M.E., Reisman, D.J., and Lazorchak, J.M. 2011. Metal Removal Efficiency and
Ecotoxicological Assessment of Field-Scale Passive Treatment Biochemical Reactors. Environmental
Toxicology and Chemistry, 30:385-392.
Doshi, S.M. 2006. Bioremediation of acid mine drainage using sulfate-reducing bacteria. US
Environmental Protection Agency (U.S. EPA), Office of Solid Waste and Emergency Response and Office
of Superfund Remediation and Technology Innovation. 65 pp.
Eger, P., Wagner, J., and Melchert, G. 1996. "The Use of Overland Flow Wetland Treatment Systems to
Remove Nickel from Neutral Mine Drainage. "Paper presented at the 1996 Annual Meeting of the
American Society for Surface Mining and Reclamation (ASSMR), Knoxville, TN, May 18-231996. pp. 580-
589.
Eger, P., Melchert, G., and Wagner, J. 1998. "Mine closure - Can passive treatment be successful." In
Proceedings of 15th Annual Meeting of American Society for Surface Mining and Reclamation, St. Louis,
MO, May 17-21, 1998. pp. 263-271.
Eger, P. and Beatty, C.L.K. 2013. "Constructed Wetland Treatment Systems for Mine Drainage - Can
They Really Provide Green and Sustainable Solutions?" In proceedings from the 2013 Annual
International Mine Water Association Conference, Reliable Mine Water Technology, Golden, CO, 2013.
pp 545-550. Wolkersdorfer, Brown & Figueroa (Ed.).
Eger, P. and P. Eger. 2005 "Controlling Mine Drainage Problems in Minnesota - Are All the Wetland
Treatment Systems Really Above Average?" Paper presented at the 2005 National Meeting of the
American Society of Mining and Reclamation, June 19-13, 2005. Published by ASMR, Lexington, KY. pp.
339-359.
10-27
-------
Faulkner, B.B. and F.K. Miller. 2002. "Improvement of Water Quality by Land Reclamation and Passive
Systems at an Eastern U.S. Copper Mine." Paper presented at the 2002 National Meeting of the
American Society of Mining and Reclamation, Lexington, KY, June 9-13, 2002. pp. 830-841.
Federal Remediation Technologies Roundtable (FRTR). 2007. "Constructed Wetland at Copper Basin
Mining District, in Cost and Performance Case Studies." Accessed August 22, 2019.
https://frtr.gov/costperformance/pdf/20070522 397.pdf.
Gallagher, N., Blumenstein, E., Rutkowski, T., DeAngelis, J., Reisman, D.J., and Progess, C. 2012. "Passive
Treatment of Mining Influenced Wastewater with Biochemical Reactor Treatment at the Standard Mine
Superfund Site, Crested Butte, Colorado." Paper presented at the 2012 National Meeting of American
Society of Mining and Reclamation, Tupelo, MS, Sustainable Reclamation, June 8-15, 2012. pp. 137-153.
R.I. Barnhisel (Ed.), Published by ASMR, Lexington, KY.
Interstate Technology and Regulatory Council (ITRC) Mining Waste Team. 2010. Dunka Mine, Minnesota.
Mining Waste Treatment Technology Selection Web. Washington, D.C., 2010. www.itrcweb.org.
Jarvis, A., Gandy, C., Bailey, M., Davis, J., Orme, P., Malley, J., Potter, H., and Moorhouse, A. 2015. "Metal
Removal and Secondary Contamination in a Passive Metal Mine Drainage Treatment System." Paper
presented at 10th International Conference on Acid Rock Drainage and IMWA Annual Conference,
Santiago, Chile, April 21-24, 2015. 9 pp.
Johnson, D.B. and Hallberg, K.B. 2005. Biochemistry of the compost bioreactor components of a
composite acid mine drainage passive remediation system. Science of the Total Environment, 338:81-93.
Macfas, F., Caraballo, M.A., Nieto, J.M., Rotting, T.S., and Ayora, C. 2012a. Natural pretreatment and
passive remediation of highly polluted acid mine drainage. Journal of environmental management,
104:93-100.
Macfas, F., Caraballo, M.A., Rotting, T.S., Perez-Lopez, R., Nieto, J.M., and Ayora, C. 2012b. From highly
polluted Zn-rich acid mine drainage to non-metallic waters: Implementation of a multi-step alkaline
passive treatment system to remediate metal pollution. Science of the Total Environment, 433:323-330.
Nairn, R.W., Beisel, T., Thomas, R.C., LaBar, J.A., Strevett, K.A., Fuller, D. Strosnider, W.H., Andrews, W.J.,
Bays, J., and Knox, R.C. 2009. "Challenges in Design and Construction of a Large Multi-Cell Passive
Treatment System for Ferruginous Lead-Zinc Mine Waters" Presented at the 2009 National Meeting of
the American Society of Mining Reclamation, Billings, MT, Revitalizing the Environment: Proven Solutions
and Innovative Approaches, May 30 - June 5, 2009. pp. 871-892. R.I. Barnhisel (Ed.). Published by ASMR,
Lexington, KY.
Nairn, R.W., LaBar, J.A., Strevett, K.A., Strosnider, W.H., Morris, D., Neely, C.A., Garrido, A., Santamaria,
B., Oxenford, L., Kauk, K., Carters, S., and Furneaux, B. 2010a. "A Large, Multi-Cell, Ecologically
Engineered Passive Treatment System for Ferruginous Lead-Zinc Mine Waters." Paper presented at the
2010 Annual International Mine Water Association Conference, Sydney, Nova Scotia, September 5-9. pp
255-258. Wolkersdorfer & Freund (Ed.).
Nairn, R.W., LaBar, J.A., Strevett, K.A., Strosnider, W.H., Morris, D., Garrido, A.E., Neely, C.A., and Kauk,
K. 2010b. "Initial Evaluation of a Large Multi-Cell Passive Treatment System for Net-Alkaline Ferruginous
Lead-Zinc Mine Waters." Paper presented at the 2010 National Meeting of the American Society of
10-28
-------
Mining Reclamation, Pittsburgh, PA, Bridging Reclamation, Science and the Community, June 5 - 11. R.I.
pp. 635-649. Barnhisel (Ed.). Published by ASMR, Lexington, KY.
Nairn, R.W., LaBar, J.A., and Strevett, K.A. 2011. "Passive Treatment Opportunities in a Drastically
Disturbed Watershed: Reversing the Irreversible." Paper presented at the 2011 National Meeting of the
American Society of Mining and Reclamation, Bismarck, ND, Reclamation: Sciences Leading to Success,
June 11 - 16. pp. 450-468. R.I. Barnhisel (Ed.). Published by ASMR, Lexington, KY.
Nordwick, S. and D. R. Bless. 2008. Final Report- An Integrated Passive Biological Treatment System.
U.S. Environmental Protection Agency, Mine Waste Technology Program Report #16. (EPA/600/R-
09/158).
Nordwick, S., Zaluski, M., Park, B., and Bless, D. 2006. "Advances in Development of Bioreactors
Applicable to the Treatment of ARD." Presented at the 7th International Conference on Acid Rock
Drainage (ICARD), St. Louis, Mo, March 26-30, 2006. pp.1410-1420. R.I. Barnhisel (ed.). Published by
ASMR, Lexington, KY.
Reisman, D., Rutkowski, T., Smart, P., Gusek, J. and Sieczkowski, M. 2009. "Passive Treatment and
Monitoring at the Standard Mine Superfund Site, Crested Butte, CO." Paper presented at the 2009
National Meeting of American Society of Mining and Reclamation, Billings, MT, Revitalizing the
Environment: Proven Solutions and Innovative Approaches May 30 -June 5, 2009. pp. 1107-1128. R.I.
Barnhisel (Ed.). Published by ASMR, Lexington, KY.
Rotting, T.S., Caraballo, M.A., Serrano, J.A., Ayora, C., and Carrera, J. 2008. Field application of calcite
Dispersed Alkaline Substrate (calcite-DAS) for passive treatment of acid mine drainage with high Al and
metal concentrations. Applied Geochemistry, 23(6), pp.1660-167.
Seal, R.R., Hammarstrom, J.M., Bishop, A., Piatak, N.M., Levitan, D.M., Epp, E., and Sobeck, R.G. 2008.
"Water Quality Before and After Reclamation at the Abandoned Valcinzo Zn-Pb Mine Site, Spotsylvania
County, Virginia." Presented at the 2008 National Meeting of the American Society of Mining and
Reclamation, Richmond, VA, 2008. R.I. Barnhisel (Ed.). Published by ASMR, Lexington, KY. pp. 969-996.
Sobeck, R.G., Perry, J.E., Bishop, A., Epp, E. 2008. "Acid Mine Reclamation in Spotsylvania County,
Virginia, USE: Using Water Chemistry and Vegetation Re-establishment as a Measure of Success."
Presented at the 2008 National Meeting of the ASMR, Richmond, VA, 2008. R.I. Barnhisel (Ed.).
Published by ASMR, Lexington, KY. pp. 1039-1069.
U.S. Environmental Protection Agency (U.S. EPA). 2006a. Compost-Free Bioreactor Treatment of Acid
Rock Drainage, Leviathan Mine, California Innovative Technology Evaluation Report. (EPA/540/R-
06/009.)
U.S. Environmental Protection Agency (U.S. EPA). 2006b. Abandoned Mine Lands Innovative Technology
Case Study, Copper Basin Mining District, https://semspub.epa.gov/work/04/11121242.pdf.
U.S. Environmental Protection Agency (U.S. EPA). 2002. Final Report - Sulfate-Reducing Bacteria
Reactive Wall Demonstration, Mine Waste Technology Program Activity III, Project 12 by Wilmoth, R.
(EPA/600/R-02/053). 69 pp.
10-29
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Whitehead, P.G., Hall, G., Neal, C. and Prior, H. 2005. Chemical Behavior of the Wheal Jane
Bioremediation System. Science of the Total Environment, 338:41-51.
Whitehead, P.G. and Prior, H. 2005. Bioremediation of acid mine drainage: an introduction to the Wheal
Jane wetlands project. Science of the Total Environment, 338:15-21.
10-30
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Appendix A: Biochemical Reactors Data Tables
Appendix A: Biochemical Reactors Data Tables
Table A-l: Maximum and Minimum Influent and Corresponding Effluent Concentrations - All Applicable Case Studies
Constituent
Water
Sample
Maximum
Influent
Corresponding
Effluent
Minimum
Influent
Corresponding
Effluent
Mine
Source
Solid substrate
Sulfate
NS
195
150
114
117
Cwm Rheidol3
Jarvis et al., 2014
(Figure 42)
Zinc
Total
15.5
2.5
9
4.1
Cwm Rheidol3
Jarvis et al., 2014
(Figure 37)
Zinc
Dissolved
15.5
<0.01
9
4
Cwm Rheidol3
Jarvis et al., 2014
(Figure 37)
PH
NA
3.5
7.5
4.8
7.25
Cwm Rheidol3
Jarvis et al., 2014
(Figure 40)
Sulfate
Not
specified
165
145
92
85
Nenthead
Jarvis et al., 2014
(Figure 32)
Zinc
Total
4.5
0.5
1.7
0.5
Nenthead
Jarvis et al., 2014
(Figure 30)
Zinc
Dissolved
4.5
0.25
1.7
0.2
Nenthead
Jarvis et al., 2014
(Figure 30)
Cadmium
Dissolved
0.2
0.00025
0.027
Not plotted
Standard
Gallagher et al.,
2012
(Figure 3)
Copper
Dissolved
0.99
0.002
0.003
0.0013
Standard
Gallagher et al.,
2012
(Figure 4)
Iron
Total
89.8
0.7
lb
0.025
Standard
Gallagher et al.,
2012
(Figure 5)
Lead
Dissolved
2.07
0.0011
0.011
0.0009
Standard
Gallagher et al.,
2012
(Figure 6)
A-l
-------
Appendix A: Biochemical Reactors Data Tables
Table A-l: Maximum and Minimum Influent and Corresponding Effluent Concentrations - All Applicable Case Studies
Constituent
Water
Sample
Maximum
Influent
Corresponding
Effluent
Minimum
Influent
Corresponding
Effluent
Mine
Source
Manganese
Dissolved
13.2
10
5.4
7
Standard
Gallagher et al.,
2012
(Figure 7)
Sulfate
NA
400
200
150
110
Standard
Gallagher et al.,
2012
(Figure 9)
Zinc
Dissolved
32.1
0.01
14.9
0.006
Standard
Gallagher et al.,
2012
(Figure 8)
Sulfate
Dissolved
38.2
Not provided
19.3
Not provided
Force Crag, VP1
and VP2
Jarvis et al., 2015
(Text)
Zinc
Total
4.5
0.02
2.2
0.04
Force Crag, VFP1
Jarvis et al., 2015
(Figure 2)
Zinc
Total
4.5
0.22
2.2
0.06
Force Crag, VFP2
Jarvis et al., 2015
(Figure 2)
Arsenic
Dissolved
1.25
0.01
0.125
0.01
Surething
(Reactor l)c
Nordwick and
Bless, 2008
(Figure 4-6)
Cadmium
Dissolved
0.385
0.005
0.040
0.0001
Surething
(Reactor l)c
Nordwick and
Bless, 2008
(Figure 4-3)
Copper
Dissolved
4.25
<0.003
0.500
<0.003
Surething
(Reactor l)c
Nordwick and
Bless, 2008
(Figure 4-2)
Iron
Dissolved
51
0.014
12.5
10.625
Surething
(Reactor l)c
Nordwick and
Bless, 2008
(Figure 4-5)
Manganese
Dissolved
65
20
4.55
6.36
Surething
(Reactor l)c
Nordwick and
Bless, 2008
(Figure 4-7)
Sulfate
Dissolved
900
450
40
106
Surething
(Reactor l)c
Nordwick and
Bless, 2008
(Figure 4-14)
A-2
-------
Appendix A: Biochemical Reactors Data Tables
Table A-l: Maximum and Minimum Influent and Corresponding Effluent Concentrations - All Applicable Case Studies
Constituent
Water
Sample
Maximum
Influent
Corresponding
Effluent
Minimum
Influent
Corresponding
Effluent
Mine
Source
Zinc
Dissolved
39
<0.007
4.5
<0.007
Surething
(Reactor l)c
Nordwick and
Bless, 2008
(Figure 4-4)
Cadmium
Total
0.17
<0.0024
0.11
<0.0024
Standardd
Reisman et al.,
2009
(Figure 7)
Cadmium
Dissolved
0.17
<0.0024
0.11
<0.0024
Standardd
Reisman et al.,
2009
(Figure 7)
Copper
Total
1.03
0.0055
0.13
<0.0038
Standardd
Reisman et al.,
2009
(Figure 8)
Copper
Dissolved
1.01
<0.0038
0.080
0.005
Standardd
Reisman et al.,
2009
(Figure 8)
Iron
Total
21
0.21
0.17
15
Standardd
Reisman et al.,
2009
(Figure 9)
Iron
Dissolved
8
0.17
0.08
4.5
Standardd
Reisman et al.,
2009
(Figure 9)
Lead
Total
6
<0.008
0.23
0.016
Standardd
Reisman et al.,
2009
(Figure 10)
Lead
Dissolved
2.50
<0.008
0.02
0.008
Standardd
Reisman et al.,
2009
(Figure 10)
Manganese
Total
14
10
6
7.5
Standardd
Reisman et al.,
2009
(Figure 11)
Manganese
Dissolved
12.71
10.5
5.34
8
Standardd
Reisman et al.,
2009
(Figure 11)
A-3
-------
Appendix A: Biochemical Reactors Data Tables
Table A-l: Maximum and Minimum Influent and Corresponding Effluent Concentrations - All Applicable Case Studies
Constituent
Water
Sample
Maximum
Influent
Corresponding
Effluent
Minimum
Influent
Corresponding
Effluent
Mine
Source
Zinc
Total
30.9
0.8
21e
0.9
Standardd
Reisman et al.,
2009
(Figure 12)
Zinc
Dissolved
30.9
0.4
21
1.5
Standardd
Reisman et al.,
2009
(Figure 12)
Aluminum
Total
14.1
0.0453
0.011
0.0094
Calliope (BCR lll)f
Wilmoth, 2002
(Table 5-6)
Arsenic
Total
0.0109
0.0035
0.0051
<0.005
Calliope (BCR lll)f
Wilmoth, 2002
Cadmium
Total
0.0419
0.0048
0.0051
0.0056
Calliope (BCR lll)f
(Table 5-6)
Copper
Total
3.05
0.0434
0.0072
0.0195
Calliope (BCR lll)f
Wilmoth, 2002
Iron
Total
7.22
0.149
0.008
0.031
Calliope (BCR lll)f
(Table 5-6)
Manganese
Total
3.77
2.10
0.69
0.076
Calliope (BCR lll)f
Wilmoth, 2002
Sulfate
Total
229
223
60.6
60
Calliope (BCR lll)f
Wilmoth, 2002
(Table 5-4)
Zinc
Total
11.1
0.459
0.99
0.790
Calliope (BCR lll)f
Wilmoth, 2002
(Table 5-6)
PH
NA
3.29
7.56
7.52
6.79
Calliope (BCR lll)f
Wilmoth, 2002
(Table 5-2)
Nitrate
NS
7.9
ND
2.9
0.1
Confidential
Mine8
Blumenstein and
Gusek, 2009
(Figure 9)
Selenium
NS
0.025
ND
0.01
ND
Confidential
Mine8
Blumenstein and
Gusek, 2009
(Figure 8)
Thallium
NS
1.6
<0.001
0.25
<0.001
Confidential
Mine8,h
Blumenstein and
Gusek, 2009
(Figure 7)
PH
NA
7.0
6.8
8.0
7.2
Confidential
Mine8
Blumenstein and
Gusek, 2009
(Figure 2)
A-4
-------
Appendix A: Biochemical Reactors Data Tables
Table A-l: Maximum and Minimum Influent and Corresponding Effluent Concentrations - All Applicable Case Studies
Constituent
Water
Maximum
Corresponding
Minimum
Corresponding
Mine
Source
Sample
Influent
Effluent
Influent
Effluent
Liquid Substrate
Arsenic
Total
0.07
0.008
0.018
0.001
Keno Hill1
Harrington et al.,
2015
(Figure 2)
Cadmium
Total
0.0016
<0.0001
0.0011
<0.0001
Keno Hill1
Harrington et al.,
2015
(Figure 2)
Manganese
Total
19
20
15
16
Keno Hill'
Harrington et al.,
2015
(Figure 2)
Zinc
Total
6.2
0.01
4.8
0.55
Keno Hill1
Harrington et al.,
2015
(Figure 2)
Aluminum
Dissolved
34.2
26.1
26.1
22.2
Leviathan -
gravity modeJ
U.S. EPA, 2006a
(Table 2-13)
Aluminum
Total
36.3
28.3
28.3
22.7
Leviathan -
gravity modeJ
U.S. EPA, 2006a
(Table 2-17)
Aluminum
Dissolved
0.155
0.104
0.104
0.108
Leviathan -
recirculation
modeJ
U.S. EPA, 2006a
(Table 2-15)
Aluminum
Total
1.170
0.389
0.389
0.334
Leviathan -
recirculation
modeJ
U.S. EPA, 2006a
(Table 2-18)
Arsenic
Dissolved
0.003
<0.0023
0.0028
<0.0023
Leviathan -
gravity modeJ
U.S. EPA, 2006a
(Table 2-13)
Arsenic
Total
<0.0023
0.0034
<0.0022
<0.0023
Leviathan -
gravity modeJ
U.S. EPA, 2006a
(Table 2-17)
Arsenic
Dissolved
0.0059
0.005
0.0044
0.0059
Leviathan -
recirculation
modeJ
U.S. EPA, 2006a
(Table 2-15)
A-5
-------
Appendix A: Biochemical Reactors Data Tables
Table A-l: Maximum and Minimum Influent and Corresponding Effluent Concentrations - All Applicable Case Studies
Constituent
Water
Sample
Maximum
Influent
Corresponding
Effluent
Minimum
Influent
Corresponding
Effluent
Mine
Source
Arsenic
Total
<0.0021
<0.0021
<0.0021
0.0026
Leviathan -
recirculation
modeJ
U.S. EPA, 2006a
(Table 2-18)
Cadmium
Dissolved
<0.00023
<0.00023
<0.0023
<0.0023
Leviathan -
gravity modeJ
U.S. EPA, 2006a
(Table 2-13)
Cadmium
Total
0.00042
<0.00023
<0.00023
<0.00023
Leviathan -
gravity modeJ
U.S. EPA, 2006a
(Table 2-17)
Cadmium
Dissolved
0.00035
0.00021
0.00021
0.00041
Leviathan -
recirculation
modeJ
U.S. EPA, 2006a
(Table 2-15)
Cadmium
Total
0.00023
<0.00016
<0.00016
0.0026
Leviathan -
recirculation
modeJ
U.S. EPA, 2006a
(Table 2-18)
Chromium
Dissolved
0.0139
0.0133
0.0133
0.0143
Leviathan -
gravity modeJ
U.S. EPA, 2006a
(Table 2-13)
Chromium
Total
0.0147
0.0139
0.0139
0.0128
Leviathan -
gravity modeJ
U.S. EPA, 2006a
(Table 2-17)
Chromium
Dissolved
0.0122
0.0118
0.0118
0.012
Leviathan -
recirculation
modeJ
U.S. EPA, 2006a
(Table 2-15)
Chromium
Total
0.012
0.012
0.012
0.0117
Leviathan -
recirculation
modeJ
U.S. EPA, 2006a
(Table 2-18)
Copper
Dissolved
0.614
0.0057
0.0057
0.0061
Leviathan -
gravity modeJ
U.S. EPA, 2006a
(Table 2-13)
Copper
Total
0.653
0.0676
0.0676
0.0537
Leviathan -
gravity modeJ
U.S. EPA, 2006a
(Table 2-17)
Copper
Dissolved
0.0083
0.0071
0.0071
0.0076
Leviathan -
recirculation
modeJ
U.S. EPA, 2006a
(Table 2-15)
Copper
Total
0.0243
0.0107
0.0107
0.0114
Leviathan -
recirculation
modeJ
U.S. EPA, 2006a
(Table 2-18)
A-6
-------
Appendix A: Biochemical Reactors Data Tables
Table A-l: Maximum and Minimum Influent and Corresponding Effluent Concentrations - All Applicable Case Studies
Constituent
Water
Sample
Maximum
Influent
Corresponding
Effluent
Minimum
Influent
Corresponding
Effluent
Mine
Source
Iron
Dissolved
73.1
71.7
71.1
63.7
Leviathan -
gravity modeJ
U.S. EPA, 2006a
(Table 2-13)
Iron
Total
87.0
77.7
77.7
63.7
Leviathan -
gravity modeJ
U.S. EPA, 2006a
(Table 2-17)
Iron
Dissolved
0.266
0.247
0.266
0.247
Leviathan -
recirculation
modeJ
U.S. EPA, 2006a
(Table 2-15)
Iron
Total
7.93
3.14
3.14
2.69
Leviathan -
recirculation
modeJ
U.S. EPA, 2006a
(Table 2-18)
Lead
Dissolved
0.0058
0.0058
0.0058
0.005
Leviathan -
gravity modeJ
U.S. EPA, 2006a
(Table 2-13)
Lead
Total
0.0059
0.0055
0.0055
0.0044
Leviathan -
gravity modeJ
U.S. EPA, 2006a
(Table 2-17)
Lead
Dissolved
0.0042
0.0042
0.0042
0.0040
Leviathan -
recirculation
modeJ
U.S. EPA, 2006a
(Table 2-15)
Lead
Total
0.0047
0.0038
0.0043
0.0047
Leviathan -
recirculation
modeJ
U.S. EPA, 2006a
(Table 2-18)
Nickel
Dissolved
0.449
0.35
0.350
0.300
Leviathan -
gravity modeJ
U.S. EPA, 2006a
(Table 2-13)
Nickel
Total
0.475
0.37
0.37
0.30
Leviathan -
gravity modeJ
U.S. EPA, 2006a
(Table 2-17)
Nickel
Dissolved
0.0726
0.0117
0.0117
0.0102
Leviathan -
recirculation
modeJ
U.S. EPA, 2006a
(Table 2-15)
Nickel
Total
0.0734
0.0334
0.0334
0.0286
Leviathan -
recirculation
modeJ
U.S. EPA, 2006a
(Table 2-18)
Selenium
Dissolved
0.0142
0.0108
0.0108
0.0106
Leviathan -
gravity modeJ
U.S. EPA, 2006a
(Table 2-13)
A-7
-------
Appendix A: Biochemical Reactors Data Tables
Table A-l: Maximum and Minimum Influent and Corresponding Effluent Concentrations - All Applicable Case Studies
Constituent
Water
Sample
Maximum
Influent
Corresponding
Effluent
Minimum
Influent
Corresponding
Effluent
Mine
Source
Selenium
Total
0.014
0.0124
0.0124
0.0099
Leviathan -
gravity modeJ
U.S. EPA, 2006a
(Table 2-17)
Selenium
Dissolved
0.0114
0.0116
0.0075
0.0114
Leviathan -
recirculation
modeJ
U.S. EPA, 2006a
(Table 2-15)
Selenium
Total
0.0124
0.0103
0.0103
0.0089
Leviathan -
recirculation
modeJ
U.S. EPA, 2006a
(Table 2-18)
Sulfate
Total
1520
1480
1480
1310
Leviathan -
gravity modeJ
U.S. EPA, 2006a
(Table 2-9)
Sulfate
Total
1190
1160
1160
1090
Leviathan -
recirculation
modeJ
U.S. EPA, 2006a
(Table 2-11)
Sulfide
Dissolved
37
38
0
37
Leviathan -
gravity modeJ
U.S. EPA, 2006a
(Table 2-9)
Sulfide
Dissolved
27
50
0
27
Leviathan -
recirculation
modeJ
U.S. EPA, 2006a
(Table 2-11)
Zinc
Dissolved
0.661
0.032
0.032
0.0288
Leviathan -
gravity modeJ
U.S. EPA, 2006a
(Table 2-13)
Zinc
Total
0.714
0.125
0.125
0.0927
Leviathan -
gravity modeJ
U.S. EPA, 2006a
(Table 2-17)
Zinc
Dissolved
0.0172
0.0063
0.0063
0.0104
Leviathan -
recirculation
modeJ
U.S. EPA, 2006a
(Table 2-15)
Zinc
Total
0.028
0.0137
0.0137
0.0146
Leviathan -
recirculation
modeJ
U.S. EPA, 2006a
(Table 2-18)
PH
NA
3.6
4.7
4.7
4.8
Leviathan -
gravity modeJ
U.S. EPA, 2006a
(Table 2-9)
PH
NA
7.2
7.2
7.2
7.3
Leviathan -
recirculation
modeJ
U.S. EPA, 2006a
(Table 2-11)
A-8
-------
Appendix A: Biochemical Reactors Data Tables
Table A-l: Maximum and Minimum Influent and Corresponding Effluent Concentrations - All Applicable Case Studies
Constituent
Water
Sample
Maximum
Influent
Corresponding
Effluent
Minimum
Influent
Corresponding
Effluent
Mine
Source
Notes:
All analytical results reported in mg/L
pH results reported in standard units
NA = not applicable
NS = not specified
ND = Assumed not detected based on figures referenced; detection limits unknown
a = Cwm Rheidol data used were from post-May 2011, which were deemed most representative of the capabilities of the BCR due to initial
increasing zinc concentrations
b = The minimum influent concentration reported was 0.89 mg/L; however, the corresponding effluent concentration was higher than this.
Therefore, the data were considered anomalous and the next lowest influent concentration and its corresponding effluent concentration were
chosen
c = Influent to Reactor 1 is labeled "feed" in the referenced figures and the effluent for Reactor 1 is labeled "SP1" in the referenced figures
d = Data used were from after the start-up period, which is shown in the figures as September 2007; influent concentrations were verified in
text if available
e = The minimum influent concentration reported was 0.1 mg/L for total zinc, but this concentration was lower than the dissolved
concentration and considered anomalous. The next lowest influent concentration and its corresponding effluent concentration were chosen,
f = BCR III was the only BCR without pre-treatment
g = Data used were from post-December 2007, after the two-month flushing maturation period
h = Excludes thallium data from BCR overload event, shown on Figure 7
i = Keno Hill data used were from post-August 2009, which corresponds to the start of sulfate-reducing conditions in the BCR; data were
approximated from figures
j = Leviathan gravity flow configuration data March 24, 2004; recirculation flow configuration data August 19, 2004. Maximum and minimum
influent concentrations for Leviathan determined by comparison of the two BCRs within each of the operating modes
A-9
-------
Appendix A: Biochemical Reactors Data Tables
Table A-2: Average Influent and Effluent Concentrations - All Applicable Case Studies
Constituent
Water
Sample
Average
Influent
Average Effluent
Mine
Source
Notes
Solid Substrate
Aluminum
Dissolved
9.7
<0.02
Lilly/Orphan Boy
Bless et al., 2008
(Table 1)
EPA calculated average effluent
based on March and May 2001
sampling events of treated tunnel
water; the average influent was
reported in the source as average
of "several samples" taken from
September 1993 until August 1994
Arsenic
Dissolved
1.07
0.075
Lilly/Orphan Boy
Bless et al., 2008
(Table 1)
EPA calculated average effluent
based on March and May 2001
sampling events of treated tunnel
water; the average influent was
reported in the source as average
of "several samples" taken from
September 1993 until August 1994
Cadmium
Dissolved
0.33
<0.005
Lilly/Orphan Boy
Bless et al., 2008
(Table 1)
EPA calculated average effluent
based on March and May 2001
sampling events of treated tunnel
water; the average influent was
reported in the source as average
of "several samples" taken from
September 1993 until August 1994
Copper
Dissolved
0.32
0.012a
Lilly/Orphan Boy
Bless et al., 2008
(Table 1)
EPA calculated average effluent
based on March and May 2001
sampling events of treated tunnel
water; the average influent was
reported in the source as average
of "several samples" taken from
September 1993 until August 1994
Iron
Dissolved
27.7
11.25
Lilly/Orphan Boy
Bless et al., 2008
(Table 1)
EPA calculated average effluent
based on March and May 2001
sampling events of treated tunnel
water; the average influent was
A-10
-------
Appendix A: Biochemical Reactors Data Tables
Table A-2: Average Influent and Effluent Concentrations - All Applicable Case Studies
Constituent
Water
Sample
Average
Influent
Average Effluent
Mine
Source
Notes
reported in the source as average
of "several samples" taken from
September 1993 until August 1994
Manganese
Dissolved
6.2
2.05
Lilly/Orphan Boy
Bless et al., 2008
(Table 1)
EPA calculated average effluent
based on March and May 2001
sampling events of treated tunnel
water; the average influent was
reported in the source as average
of "several samples" taken from
September 1993 until August 1994
Sulfate
Dissolved
277
136.5
Lilly/Orphan Boy
Bless et al., 2008
(Table 1)
EPA calculated average effluent
based on March and May 2001
sampling events of treated tunnel
water; the average influent was
reported in the source as average
of "several samples" taken from
September 1993 until August 1994
Zinc
Dissolved
26.1
0.032a
Lilly/Orphan Boy
Bless et al., 2008
(Table 1)
EPA calculated average effluent
based on March and May 2001
sampling events of treated tunnel
water; the average influent was
reported in the source as average
of "several samples" taken from
September 1993 until August 1994
PH
Dissolved
3.0
7.2
Lilly/Orphan Boy
Bless et al., 2008
(Table 1)
EPA calculated average effluent
based on March and May 2001
sampling events of treated tunnel
water; the average influent was
reported in the source as average
of "several samples" taken from
September 1993 until August 1994.
Average for pH is average of the pH
values provided in source.
A-ll
-------
Appendix A: Biochemical Reactors Data Tables
Table A-2: Average Influent and Effluent Concentrations - All Applicable Case Studies
Constituent
Water
Sample
Average
Influent
Average Effluent
Mine
Source
Notes
Cadmium
Dissolved
0.14
<0.002
Standard
Reisman et al., 2009
(Table 1)
September 2007 - September 2008
Cadmium
Dissolved
0.095b
0.00019
Standard
Gallagher et al.,
2012
(Text)
August 2008 - November 2011
Copper
Dissolved
0.26
<0.0038
Standard
Reisman et al., 2009
(Table 1)
September 2007 - September 2008
Copper
Dissolved
0.10b
0.0014
Standard
Gallagher et al.,
2012
(Text)
August 2008 - November 2011
Iron
Total
5.23
2.01
Standard
Reisman et al., 2009
(Table 1)
September 2007 - September 2008
Iron
Total
11.2b
0.56
Standard
Gallagher et al.,
2012
(Text)
August 2008 - November 2011
Lead
Dissolved
0.54
0.01
Standard
Reisman et al., 2009
(Table 1)
September 2007 - September 2008
Lead
Dissolved
0.134b
0.00215
Standard
Gallagher et al.,
2012
(Text)
August 2008 - November 2011
Manganese
Dissolved
10.99
10.53
Standard
Reisman et al., 2009
(Table 1)
September 2007 - September 2008
Sulfate
Dissolved
281
119
Standard
Gallagher et al.,
2012
(Text)
August 2008 - November 2011
Sulfide
Dissolved
<0.5
12.5
Standard
Gallagher et al.,
2012
(Text)
August 2008 - November 2011
Zinc
Dissolved
26.46
0.55
Standard
Reisman et al., 2009
(Table 1)
September 2007 - September 2008
Zinc
Dissolved
18.25b
0.073
Standard
Gallagher et al.,
2012
(Text)
August 2008 - November 2011
A-12
-------
Appendix A: Biochemical Reactors Data Tables
Table A-2: Average Influent and Effluent Concentrations - All Applicable Case Studies
Constituent
Water
Sample
Average
Influent
Average Effluent
Mine
Source
Notes
Aluminum
Dissolved
1.2229
0.0616
Calliope
Wilmoth, 2002°
(Table 5-6)
BCR III effluent
Arsenic
Dissolved
<0.005
<0.005
Calliope
Wilmoth, 2002°
(Table 5-6)
BCR III effluent
Cadmium
Dissolved
0.0112
<0.005
Calliope
Wilmoth, 2002°
(Table 5-6)
BCR III effluent
Copper
Dissolved
0.4078
0.0546
Calliope
Wilmoth, 2002°
(Table 5-6)
BCR III effluent
Iron
Dissolved
0.4556
0.4143
Calliope
Wilmoth, 2002°
(Table 5-6)
BCR III effluent
Manganese
Dissolved
1.4581
1.0073
Calliope
Wilmoth, 2002°
(Table 5-6)
BCR III effluent
Sulfate
Dissolved
0.1029
0.1039
Calliope
Wilmoth, 2002°
(Table 5-4)
BCR III effluent
Zinc
Dissolved
2.8406
0.7944
Calliope
Wilmoth, 2002°
(Table 5-6)
BCR III effluent
PH
NA
6.05
7.16
Calliope
Wilmoth, 2002°
(Table 5-1)
BCR III effluent
Sulfate
Dissolved
30.4
10.1
Force Crag
Jarvis et al., 2015
(Text)
VFP1
Sulfate
Dissolved
30.4
8.1
Force Crag
Jarvis et al., 2015
(Text)
VFP2
Nitrate
NS
5.1
0.08
Confidential Mine
Blumenstein and
Gusek, 2009 (Text)
Over 14 months of operation
Selenium
NS
0.013
0.001
Confidential Mine
Blumenstein and
Gusek, 2009 (Text)
Over 14 months of operation
Thallium
NS
1.25
0.007
Confidential Mine
Blumenstein and
Gusek, 2009 (Text)
Over 14 months of operation;
average effluent influenced by two
upset events
Liquid Substrate (Not available)
Notes:
All analytical results reported in mg/L
A-13
-------
Appendix A: Biochemical Reactors Data Tables
Table A-2: Average Influent and Effluent Concentrations - All Applicable Case Studies
Constituent
Water
Average
Average Effluent
Mine
Source
Notes
Sample
Influent
pH results reported in standard units
NA = not applicable
NS = not specified
a = % detection limit (DL) was used for samples reported as
-------
Appendix A: Biochemical Reactors Data Tables
Table A-3: Removal Efficiencies - All Applicable Sites
Constituent
Average Removal
Efficiency
Maximum
Minimum
Mine
Source
Solid Substrate
Total Zinc
68.00%a
85%
37%
Nenthead
Jarvis et al., 2014
(Figure 34; Text)
Dissolved Zinc
84%a
95%
68%
Nenthead
Jarvis et al., 2014
(Figure 26; Text)
Total Zincb
63%
85%
50%
Cwm Rheidol
Jarvis et al., 2014
(Figure 38)
Dissolved Zincb
76%
100%
50%
Cwm Rheidol
Jarvis et al., 2014
(Figure 39)
Dissolved Cadmium
99.8%
NA
NA
Standard
Gallagher et al., 2012
(Text)
Dissolved Copper
98.6%
NA
NA
Standard
Gallagher et al., 2012
(Text)
Total Iron
95%
NA
NA
Standard
Gallagher et al., 2012
(Text)
Dissolved Lead
98.4%
NA
NA
Standard
Gallagher et al., 2012
(Text)
Sulfate0
57.2%
NA
NA
Standard
Gallagher et al., 2012
(Text)
Dissolved Zinc
99.6%
NA
NA
Standard
Gallagher et al., 2012
(Text)
Total Zinc
98.70%
NA
NA
Force Crag, VFP1
Jarvis et al., 2015
(Text)
Total Zinc
94.10%
NA
NA
Force Crag, VFP2
Jarvis et al., 2015
(Text)
Total Zinc
96.80%
NA
NA
Force Crag, overall
system
Jarvis et al., 2015
(Text)
Cadmium0
98.50%
NA
NA
Standard
Reisman et al., 2009
(Text)
Copper0
98.60%
NA
NA
Standard
Reisman et al., 2009
(Text)
Iron0
65.00%
NA
NA
Standard
Reisman et al., 2009
(Text)
A-15
-------
Appendix A: Biochemical Reactors Data Tables
Table A-3: Removal Efficiencies - All Applicable Sites
Constituent
Average Removal
Efficiency
Maximum
Minimum
Mine
Source
Lead0
98.10%
NA
NA
Standard
Reisman et al., 2009
(Text)
Zinc0
97.90%
NA
NA
Standard
Reisman et al., 2009
(Text)
Total Aluminum
-6.17%
99.73%
-650.00%
Calliope - BCR IIId
Wilmoth, 2002
(Table 5-6)
Total Arsenic
28.31%
86.89%
-95.38%
Calliope - BCR IIId
Wilmoth, 2002
(Table 5-6)
Total Cadmium
76.34%
95.97%
-9.80%
Calliope-BCR IIId
Wilmoth, 2002
(Table 5-6)
Total Copper
44.07%
99.37%
-189.59%
Calliope-BCR IIId
Wilmoth, 2002
(Table 5-6)
Total Iron
-801.74%
97.94%
-14275.00%
Calliope-BCR IIId
Wilmoth, 2002
(Table 5-6)
Total Manganese
30.86%
98.05%
-108.22%
Calliope-BCR IIId
Wilmoth, 2002
(Table 5-6)
Total Sulfate
-2.09%
32.20%
-68.63%
Calliope-BCR IIP
Wilmoth, 2002
(Table 5-4)
Total Zinc
58.24%
99.21%
-11.97%
Calliope-BCR IIId
Wilmoth, 2002
(Table 5-6)
Nitrate0
98.43%f
>99%g
96.55%f
Confidential Mine
Blumenstein and
Gusek, 2009 (Figure 9)
Selenium0
>99%a
>99%g
>99%g
Confidential Mine
Blumenstein and
Gusek, 2009 (Text,
Figure 8)
Thallium0
>99%a
99.97%f
99.8%f
Confidential Mine
Blumenstein and
Gusek, 2009 (Text,
Figure 7)
Liquid Substrate
Total Aluminum
NA
22%
19.8%
Leviathan - gravity flow
modeh'
U.S. EPA, 2006a
(Table 2-17)
Dissolved Aluminum
NA
23.7%
14.9%
Leviathan - gravity flow
modeh'
U.S. EPA, 2006a
(Table 2-13)
A-16
-------
Appendix A: Biochemical Reactors Data Tables
Table A-3: Removal Efficiencies - All Applicable Sites
Constituent
Average Removal
Efficiency
Maximum
Minimum
Mine
Source
Total Aluminum
NA
66.8%
14.1%
Leviathan -
recirculation modeh'
U.S. EPA, 2006a
(Table 2-18)
Dissolved Aluminum
NA
32.9%
0%
Leviathan -
recirculation modeh''
U.S. EPA, 2006a
(Table 2-15)
Total Arsenic
NA
NC (influent < DL)
NC (influent < DL)
Leviathan - gravity flow
modeh''
U.S. EPA, 2006a
(Table 2-17)
Dissolved Arsenic
NA
NC (influent < DL)
NC (influent < DL)
Leviathan - gravity flow
modeh''
U.S. EPA, 2006a
(Table 2-13)
Total Arsenic
NA
NC (influent < DL)
NC (influent < DL)
Leviathan -
recirculation modeh'
U.S. EPA, 2006a
(Table 2-18)
Dissolved Arsenic
NA
NC (influent < DL)
NC (influent < DL)
Leviathan -
recirculation modeh'
U.S. EPA, 2006a
(Table 2-15)
Total Cadmium
NA
45.2%
0%
Leviathan - gravity flow
modeh''
U.S. EPA, 2006a
(Table 2-17)
Dissolved Cadmium
NA
NC (influent < DL)
NC (influent < DL)
Leviathan - gravity flow
modeh''
U.S. EPA, 2006a
(Table 2-13)
Total Cadmium
NA
NC (influent < DL)
NC (influent < DL)
Leviathan -
recirculation modeh''
U.S. EPA, 2006a
(Table 2-18)
Dissolved Cadmium
NA
40.0%
0%
Leviathan -
recirculation modeh'
U.S. EPA, 2006a
(Table 2-15)
Total Chromium
NA
7.9%
5.4%
Leviathan - gravity flow
modeh'
U.S. EPA, 2006a
(Table 2-17)
Dissolved Chromium
NA
4.3%
0%
Leviathan - gravity flow
modeh''
U.S. EPA, 2006a
(Table 2-13)
Total Chromium
NA
2.5%
0%
Leviathan -
recirculation modeh''
U.S. EPA, 2006a
(Table 2-18)
Dissolved Chromium
NA
0%
0%
Leviathan -
recirculation modeh''
U.S. EPA, 2006a
(Table 2-15)
Total Copper
NA
89.7%
20.6%
Leviathan - gravity flow
modeh'
U.S. EPA, 2006a
(Table 2-17)
Dissolved Copper
NA
99.1%
0%
Leviathan - gravity flow
modeh'
U.S. EPA, 2006a
(Table 2-13)
A-17
-------
Appendix A: Biochemical Reactors Data Tables
Table A-3: Removal Efficiencies - All Applicable Sites
Constituent
Average Removal
Efficiency
Maximum
Minimum
Mine
Source
Total Copper
NA
56%
-6.5%
Leviathan -
recirculation modeh'
U.S. EPA, 2006a
(Table 2-18)
Dissolved Copper
NA
14.5%
0%
Leviathan -
recirculation modeh''
U.S. EPA, 2006a
(Table 2-15)
Total Iron
NA
18%
10.7%
Leviathan - gravity flow
modeh''
U.S. EPA, 2006a
(Table 2-17)
Dissolved Iron
NA
11.2%
1.9%
Leviathan - gravity flow
modeh''
U.S. EPA, 2006a
(Table 2-13)
Total Iron
NA
60.4%
14.3%
Leviathan -
recirculation modeh'
U.S. EPA, 2006a
(Table 2-18)
Dissolved Iron
NA
94.6%
7.1%
Leviathan -
recirculation modeh'
U.S. EPA, 2006a
(Table 2-15)
Total Lead
NA
20%
6.8%
Leviathan - gravity flow
modeh''
U.S. EPA, 2006a
(Table 2-17)
Dissolved Lead
NA
0%
0%
Leviathan - gravity flow
modeh''
U.S. EPA, 2006a
(Table 2-13)
Total Lead
NA
19.2%
-9.3%
Leviathan -
recirculation modeh''
U.S. EPA, 2006a
(Table 2-18)
Dissolved Lead
NA
0%
0%
Leviathan -
recirculation modeh'
U.S. EPA, 2006a
(Table 2-15)
Total Nickel
NA
18.9%
22.1%
Leviathan - gravity flow
modeh'
U.S. EPA, 2006a
(Table 2-17)
Dissolved Nickel
NA
22.1%
14.3%
Leviathan - gravity flow
modeh''
U.S. EPA, 2006a
(Table 2-13)
Total Nickel
NA
54.5%
14.4%
Leviathan -
recirculation modeh''
U.S. EPA, 2006a
(Table 2-18)
Dissolved Nickel
NA
83.9%
12.8%
Leviathan -
recirculation modeh''
U.S. EPA, 2006a
(Table 2-15)
Total Selenium
NA
20.2%
11.4%
Leviathan - gravity flow
modeh'
U.S. EPA, 2006a
(Table 2-17)
Dissolved Selenium
NA
23.9%
0%
Leviathan - gravity flow
modeh'
U.S. EPA, 2006a
(Table 2-13)
A-18
-------
Appendix A: Biochemical Reactors Data Tables
Table A-3: Removal Efficiencies - All Applicable Sites
Constituent
Average Removal
Efficiency
Maximum
Minimum
Mine
Source
Total Selenium
NA
16.9%
13.6%
Leviathan -
recirculation modeh'
U.S. EPA, 2006a
(Table 2-18)
Dissolved Selenium
NA
0%
0%
Leviathan -
recirculation modeh''
U.S. EPA, 2006a
(Table 2-15)
Total Sulfate
NA
11.5%
2.6%
Leviathan - gravity flow
modeh''
U.S. EPA, 2006a
(Table 2-9)
Total Sulfate
NA
6.0%
2.5%
Leviathan -
recirculation modeh''
U.S. EPA, 2006a
(Table 2-11)
Total Zinc
NA
82.5%
25.8%
Leviathan - gravity flow
modeh'
U.S. EPA, 2006a
(Table 2-17)
Dissolved Zinc
NA
95.2%
10%
Leviathan - gravity flow
modeh'
U.S. EPA, 2006a
(Table 2-13)
Total Zinc
NA
51.1%
-6.6%
Leviathan -
recirculation modeh''
U.S. EPA, 2006a
(Table 2-18)
Dissolved Zinc
NA
63.4%
0%
Leviathan -
recirculation modeh''
U.S. EPA, 2006a
(Table 2-15)
Total Antimony
80.00%
NA
NA
Keno HillJ
Harrington et al., 2015
(Text)
Total Arsenic
80.00%
NA
NA
Keno HillJ
Harrington et al., 2015
(Text)
Total Nickel
80.00%
NA
NA
Keno HillJ
Harrington et al., 2015
(Text)
Total Zinc
99.00%
NA
NA
Keno HillJ
Harrington et al., 2015
(Text)
Notes:
DL = Detection limit
NA = Not available
NC = Not calculated
a = Average removal efficiency provided in text
b = Cwm Rheidol data used were from post-May 2011, which we deemed most representative of the capabilities of the BCR due to initial increasing zinc
concentrations; data were approximated from figures
c = Total or dissolved not specified
A-19
-------
Appendix A: Biochemical Reactors Data Tables
Table A-3: Removal Efficiencies - All Applicable Sites
Constituent
Average Removal
Efficiency
Maximum
Minimum
Mine
Source
d = EPA calculated sampling date specific removal efficiencies from the corresponding influent and effluent data provided in Table 5-6. Maximum and
minimum removal efficiencies were chosen from calculated individual removal efficiencies. The average removal efficiency for each constituent was
calculated from the individually calculated removal efficiencies.
e = EPA calculated sampling date specific removal efficiencies from the corresponding influent and effluent data provided in Table 5-4. Maximum and
minimum removal efficiencies were chosen from calculated individual removal efficiencies. The average removal efficiency for each constituent was
calculated from the individually calculated removal efficiencies.
f = EPA calculated average removal efficiency from the average influent and effluent data provided in the text of Blumenstein and Gusek, 2009. Maximum
and minimum removal efficiencies were calculated from data provided in referenced figures.
g = Assumed to be greater than 99 percent based on corresponding effluent data assumed to be at or below detection limits based on referenced figure
h = Leviathan gravity flow configuration data March 24, 2004; recirculation flow configuration data August 19, 2004
i = Minimum removal efficiencies mostly due to low concentrations into the 2nd BCR
j = Keno Hill data used were from post-August 2009, which corresponds to the start of sulfate-reducing conditions in the BCR
A-20
-------
Appendix B: Caps and Covers Data Tables
Appendix B: Caps and Covers Data Tables
Table B-l: Kristineberg Mine - Maximum and Minimum Leachate Concentrations from Capped and Uncapped Tailings
Constituent
Maximum Leachate
Maximum
Minimum
Minimum
Source
Notes
Concentration from
Leachate
Leachate
Leachate
Uncapped Cell
Concentration
from Capped
Cell
Concentration
from Uncapped
Cell
Concentration
from Capped
Cell
Cadmium
0.03
ND
ND
ND
Nason et al., 2013
(Figure 7)
Data extracted from Figure 7;
range 2005 to 2010a
Copper
0.04
0.001
0.0005
ND
Nason et al., 2013
(Figure 7)
Data extracted from Figure 7;
range 2005 to 2010a
Iron
0.022
0.005
ND
ND
Nason et al., 2013
(Figure 7)
Data extracted from Figure 7;
range 2005 to 2010a
Lead
0.00065
0.00055
0.0001
0.0001
Nason et al., 2013
(Figure 7)
Data extracted from Figure 7;
range 2005 to 2010a
Sulfur
700
220
410
15
Nason et al., 2013
(Figure 7)
Data extracted from Figure 7;
range 2005 to 2010a
Zinc
40
ND
2.5
ND
Nason et al., 2013
(Figure 7)
Data extracted from Figure 7;
range 2005 to 2010a
PH
6.2
6.8
7.6
8.2
Nason et al., 2013
(Figure 7)
Data extracted from Figure 7;
range 2005 to 2010a
Notes:
All analytical results reported as dissolved mg/L
pH results reported in standard units
ND = Assumed not detected based on Figure 7; detection limits unknown
a = Source noted that a flush of metals was observed in 2003 and subsided within a year. Values were extracted from 2005 to 2010 to be representative of
typical conditions
B-l
-------
Appendix B: Caps and Covers Data Tables
Table B-2: Dunka Mine-Average Pre-Capping and Post-Capping Concentrations
Wetland
Stockpile
Parameter
Water
Sample
Pre-Capping,
Average
Concentration
(1992 - 1994)a
Post-Capping,
Average
Concentration
(1996 - 1998)b
Post-Capping,
Average
Concentration
(1999 - 2004)c
Source
Notes
W1D
8018 and 8031
Cobalt
NS
0.036
0.009
NR
Eger and Eger, 2005
(Table 1)
Values are influent to
Wetland W1D and are
average values for period
of record.
W1D
8018 and 8031
Copper
NS
0.068
0.03
0.02
Eger and Eger, 2005
(Table 1)
Values are influent to
Wetland W1D and are
average values for period
of record.
W1D
8018 and 8031
Nickel
NS
3.98
0.74
0.76
Eger and Eger, 2005
(Table 1)
Values are influent to
Wetland W1D and are
average values for period
of record.
W1D
8018 and 8031
Zinc
NS
0.052
0.021
0.019
Eger and Eger, 2005
(Table 1)
Values are influent to
Wetland W1D and are
average values for the
period of record.
W1D
8018 and 8031
PH
NA
7.07
7.3
7.26
Eger and Eger, 2005
(Table 1)
Values are influent to
Wetland W1D and are
average of pH values for
period of record.
W2D/3D
8031
Cobalt
NS
0.02
0.02
d
Eger and Eger, 2005
(Table 1)
Values are influent to
Wetland W2D/3D and are
average values for the
period of record.
W2D/3D
8031
Copper
NS
0.05
0.05
d
Eger and Eger, 2005
(Table 1)
Values are influent to
Wetland W2D/3D and are
average values for the
period of record.
B-2
-------
Appendix B: Caps and Covers Data Tables
Table B-2: Dunka Mine-Average Pre-Capping and Post-Capping Concentrations
Wetland
Stockpile
Parameter
Water
Sample
Pre-Capping,
Average
Concentration
(1992 - 1994)a
Post-Capping,
Average
Concentration
(1996 - 1998)b
Post-Capping,
Average
Concentration
(1999 - 2004)c
Source
Notes
W2D/3D
8031
Nickel
NS
1.9
1.9
d
Eger and Eger, 2005
(Table 1)
Values are influent to
Wetland W2D/3D and are
average values for the
period of record.
W2D/3D
8031
Zinc
NS
0.05
0.05
d
Eger and Eger, 2005
(Table 1)
Values are influent to
Wetland W2D/3D and are
average values for the
period of record.
W2D/3D
8031
PH
NA
7
7
d
Eger and Eger, 2005
(Table 1)
Values are influent to
Wetland W2D/3D and are
average of pH values for
the period of record.
Notes:
All analytical results reported in mg/L
pH results reported in standard units
NS = Not specified
NR = Not reported
NA = Not applicable
a = Values are the input to the listed wetland from Table 1 of reference for 1992-1994
b = Values are the input to the listed wetland from Table 1 of reference for 1996-1998
c = Values are the input to the listed wetland from Table 1 of reference for 1999-2004
d = The source indicated that the 1999-to-2004 data for W2D/3D was estimated (values in source were identical to previous period). Therefore, it was not included in
this assessment
B-3
-------
Appendix C: Neutralization and Chemical Precipitation Data Tables
Appendix C: Neutralization and Chemical Precipitation Data Tables
Table C-l: Maximum and Minimum Influent and Corresponding Effluent Concentrations - All Applicable Case Studies
Constituent
Water
Sample
Maximum
Influent
Corresponding
Effluent
Minimum
Influent
Corresponding
Effluent
Mine
Source
Aluminum
Dissolved
119
0.584
98.6
0.575
Leviathan Mine,
Active, Single-
stage
U.S. EPA, 2006a
(Table B-l)
Arsenic
Dissolved
3.47
0.097
2.81
<0.0018
Leviathan Mine,
Active, Single-
stage
U.S. EPA, 2006a
(Table B-l)
Cadmium
Dissolved
0.0463
<0.00016
0.0132
<0.00021
Leviathan Mine,
Active, Single-
stage
U.S. EPA, 2006a
(Table B-l)
Chromium
Dissolved
0.629
0.0013
0.266
0.0116
Leviathan Mine,
Active, Single-
stage
U.S. EPA, 2006a
(Table B-l)
Copper
Dissolved
0.549
<0.0019
0.434
<0.0019
Leviathan Mine,
Active, Single-
stage
U.S. EPA, 2006a
(Table B-l)
Iron
Dissolved
545
0.0999
392
0.0057
Leviathan Mine,
Active, Single-
stage
U.S. EPA, 2006a
(Table B-l)
Lead
Dissolved
0.010
<0.0014
0.0023
<0.0009
Leviathan Mine,
Active, Single-
stage
U.S. EPA, 2006a
(Table B-l)
Nickel
Dissolved
2.76
0.0418
2.41
0.0688
Leviathan Mine,
Active, Single-
stage
U.S. EPA, 2006a
(Table B-l)
Selenium
Dissolved
0.0323
<0.0018
0.02
<0.0018
Leviathan Mine,
Active, Single-
stage
U.S. EPA, 2006a
(Table B-l)
Zinc
Dissolved
0.583
0.0026
0.49
0.0031
Leviathan Mine,
Active, Single-
stage
U.S. EPA, 2006a
(Table B-l)
c-i
-------
Appendix C: Neutralization and Chemical Precipitation Data Tables
Table C-l: Maximum and Minimum Influent and Corresponding Effluent Concentrations - All Applicable Case Studies
Constituent
Water
Sample
Maximum
Influent
Corresponding
Effluent
Minimum
Influent
Corresponding
Effluent
Mine
Source
Aluminum
Dissolved
486
1.09
326
1.14
Leviathan Mine,
Active, Dual-stage
U.S. EPA, 2006a
(Table B-2)
Arsenic
Dissolved
4.05
0.0101
1.33
0.0096
Leviathan Mine,
Active, Dual-stage
U.S. EPA, 2006a
(Table B-2)
Cadmium
Dissolved
0.0683
0.0007
0.0479
0.0009
Leviathan Mine,
Active, Dual-stage
U.S. EPA, 2006a
(Table B-2)
Chromium
Dissolved
1.24
0.0024
0.729
0.0463
Leviathan Mine,
Active, Dual-stage
U.S. EPA, 2006a
(Table B-2)
Copper
Dissolved
2.99
0.0101
2.11
0.0102
Leviathan Mine,
Active, Dual-stage
U.S. EPA, 2006a
(Table B-2)
Iron
Dissolved
653
<0.0038
336
0.243
Leviathan Mine,
Active, Dual-stage
U.S. EPA, 2006a
(Table B-2)
Lead
Dissolved
0.0122
<0.0014
0.0017
0.0044
Leviathan Mine,
Active, Dual-stage
U.S. EPA, 2006a
(Table B-2)
Nickel
Dissolved
8.77
0.0389
5.98
0.0172
Leviathan Mine,
Active, Dual-stage
U.S. EPA, 2006a
(Table B-2)
Selenium
Dissolved
0.0145
0.004
0.0046
0.0037
Leviathan Mine,
Active, Dual-stage
U.S. EPA, 2006a
(Table B-2)
Zinc
Dissolved
1.81
0.0307
1.25
0.0097
Leviathan Mine,
Active, Dual-stage
U.S. EPA, 2006a
(Table B-2)
Aluminum
Dissolved
33.6
0.254
30.9
0.185
Leviathan Mine,
Semi-Passive,
Alkaline Lagoon
U.S. EPA, 2006a
(Table B-3)
Arsenic
Dissolved
0.545
0.0129
0.485
0.0038
Leviathan Mine,
Semi-Passive,
Alkaline Lagoon
U.S. EPA, 2006a
(Table B-3)
Cadmium
Dissolved
<0.0003
<0.0003 - 0.0007
<0.00029
<0.0003
Leviathan Mine,
Semi-Passive,
Alkaline Lagoon
U.S. EPA, 2006a
(Table B-3)
Chromium
Dissolved
0.0235
0.0038
0.0162
0.0014
Leviathan Mine,
Semi-Passive,
Alkaline Lagoon
U.S. EPA, 2006a
(Table B-3)
C-2
-------
Appendix C: Neutralization and Chemical Precipitation Data Tables
Table C-l: Maximum and Minimum Influent and Corresponding Effluent Concentrations - All Applicable Case Studies
Constituent
Water
Sample
Maximum
Influent
Corresponding
Effluent
Minimum
Influent
Corresponding
Effluent
Mine
Source
Copper
Dissolved
0.0163
0.0061
0.0092
0.0031
Leviathan Mine,
Semi-Passive,
Alkaline Lagoon
U.S. EPA, 2006a
(Table B-3)
Iron
Dissolved
460
0.0172
360
0.0881
Leviathan Mine,
Semi-Passive,
Alkaline Lagoon
U.S. EPA, 2006a
(Table B-3)
Lead
Dissolved
0.0063
0.0026
0.0027
<0.0012
Leviathan Mine,
Semi-Passive,
Alkaline Lagoon
U.S. EPA, 2006a
(Table B-3)
Nickel
Dissolved
1.69
0.0472
1.57
0.0201
Leviathan Mine,
Semi-Passive,
Alkaline Lagoon
U.S. EPA, 2006a
(Table B-3)
Selenium
Dissolved
0.007
<0.0025
0.0022a
0.0036
Leviathan Mine,
Semi-Passive,
Alkaline Lagoon
U.S. EPA, 2006a
(Table B-3)
Zinc
Dissolved
0.369
0.019
0.350
0.0062
Leviathan Mine,
Semi-Passive,
Alkaline Lagoon
U.S. EPA, 2006a
(Table B-3)
PH
NA
4.59
7.92
4.59
7.92
Leviathan Mine,
Semi-Passive,
Alkaline Lagoon
U.S. EPA, 2006a
(Table 2-18)
Iron
Total
1,710
23.6
50
4
Elizabeth Mine
Butler and
Hathaway, 2020
(Table 3)
PH
NA
4.63
8.65
6.87
9.6
Elizabeth Mine
Butler and
Hathaway, 2020
(Appendices B
and E)
Notes:
All analytical results reported in mg/L
NA- Not applicable
C-3
-------
Appendix C: Neutralization and Chemical Precipitation Data Tables
Table C-l: Maximum and Minimum Influent and Corresponding Effluent Concentrations - All Applicable Case Studies
Constituent
Water
Maximum
Corresponding
Minimum
Corresponding
Mine
Source
Sample
Influent
Effluent
Influent
Effluent
Dual-stage data come from 12 sampling dates in 2002 and 1 in 2003 and the single-stage data come from 7 sampling dates in 2003; and the
semi-passive results are from 8 samples collected in 2002 except for pH; pH for semi-passive alkaline lagoon from Table 2-18 in U.S. EPA,
2006a
< = Not detected above laboratory method detection limit shown
a Value reported in reference, but below reference's stated DL
C-4
-------
Appendix C: Neutralization and Chemical Precipitation Data Tables
Table C-2: Average Influent and Effluent Concentrations - All Applicable Case Studies
Constituent
Water Sample
Average Influent
Average
Effluent
Mine
Source
Notes
Aluminum
Dissolved
107.8
0.633
Leviathan Mine, Active,
Single-stage
U.S. EPA, 2006a
(Table B-4)
Arsenic
Dissolved
3.236
0.0063
Leviathan Mine, Active,
Single-stage
U.S. EPA, 2006a
(Table B-4)
Cadmium
Dissolved
0.0261
ND
Leviathan Mine, Active,
Single-stage
U.S. EPA, 2006a
(Table B-4)
Chromium
Dissolved
0.341
0.00304
Leviathan Mine, Active,
Single-stage
U.S. EPA, 2006a
(Table B-4)
Copper
Dissolved
0.502
0.00307
Leviathan Mine, Active,
Single-stage
U.S. EPA, 2006a
(Table B-4)
Iron
Dissolved
456.428
0.176
Leviathan Mine, Active,
Single-stage
U.S. EPA, 2006a
(Table B-4)
Lead
Dissolved
0.0071
0.00156
Leviathan Mine, Active,
Single-stage
U.S. EPA, 2006a
(Table B-4)
Nickel
Dissolved
2.56
0.0468
Leviathan Mine, Active,
Single-stage
U.S. EPA, 2006a
(Table B-4)
Selenium
Dissolved
0.0271
0.00214
Leviathan Mine, Active,
Single-stage
U.S. EPA, 2006a
(Table B-4)
Zinc
Dissolved
0.538
0.00561
Leviathan Mine, Active,
Single-stage
U.S. EPA, 2006a
(Table B-4)
Aluminum
Dissolved
381
1.118
Leviathan Mine, Active,
Dual-stage
U.S. EPA, 2006a
(Table B-5)
Arsenic
Dissolved
2.239
0.00859
Leviathan Mine, Active,
Dual-stage
U.S. EPA, 2006a
(Table B-5)
Cadmium
Dissolved
0.054
0.00071
Leviathan Mine, Active,
Dual-stage
U.S. EPA, 2006a
(Table B-5)
Chromium
Dissolved
0.877
0.0057
Leviathan Mine, Active,
Dual-stage
U.S. EPA, 2006a
(Table B-5)
Copper
Dissolved
2.383
0.00805
Leviathan Mine, Active,
Dual-stage
U.S. EPA, 2006a
(Table B-5)
Iron
Dissolved
461.615
0.0449
Leviathan Mine, Active,
Dual-stage
U.S. EPA, 2006a
(Table B-5)
C-5
-------
Appendix C: Neutralization and Chemical Precipitation Data Tables
Table C-2: Average Influent and Effluent Concentrations - All Applicable Case Studies
Constituent
Water Sample
Average Influent
Average
Effluent
Mine
Source
Notes
Lead
Dissolved
0.0082
0.002
Leviathan Mine, Active,
Dual-stage
U.S. EPA, 2006a
(Table B-5)
Nickel
Dissolved
7.024
0.0342
Leviathan Mine, Active,
Dual-stage
U.S. EPA, 2006a
(Table B-5)
Selenium
Dissolved
0.0088
0.00378
Leviathan Mine, Active,
Dual-stage
U.S. EPA, 2006a
(Table B-5)
Zinc
Dissolved
1.469
0.0193
Leviathan Mine, Active,
Dual-stage
U.S. EPA, 2006a
(Table B-5)
Aluminum
Dissolved
31.988
0.251
Leviathan Mine, Semi-
Passive, Alkaline
Lagoon
U.S. EPA, 2006a
(Table B-6)
Arsenic
Dissolved
0.519
0.00584
Leviathan Mine, Semi-
Passive, Alkaline
Lagoon
U.S. EPA, 2006a
(Table B-6)
Cadmium
Dissolved
ND
0.00038
Leviathan Mine, Semi-
Passive, Alkaline
Lagoon
U.S. EPA, 2006a
(Table B-6)
Chromium
Dissolved
0.0193
0.00225
Leviathan Mine, Semi-
Passive, Alkaline
Lagoon
U.S. EPA, 2006a
(Table B-6)
Copper
Dissolved
0.0135
0.00546
Leviathan Mine, Semi-
Passive, Alkaline
Lagoon
U.S. EPA, 2006a
(Table B-6)
Iron
Dissolved
391.250
0.148
Leviathan Mine, Semi-
Passive, Alkaline
Lagoon
U.S. EPA, 2006a
(Table B-6)
Lead
Dissolved
0.0051
0.00166
Leviathan Mine, Semi-
Passive, Alkaline
Lagoon
U.S. EPA, 2006a
(Table B-6)
Nickel
Dissolved
1.631
0.0226
Leviathan Mine, Semi-
Passive, Alkaline
Lagoon
U.S. EPA, 2006a
(Table B-6)
C-6
-------
Appendix C: Neutralization and Chemical Precipitation Data Tables
Table C-2: Average Influent and Effluent Concentrations - All Applicable Case Studies
Constituent
Water Sample
Average Influent
Average
Effluent
Mine
Source
Notes
Selenium
Dissolved
0.0033
0.00324
Leviathan Mine, Semi-
Passive, Alkaline
Lagoon
U.S. EPA, 2006a
(Table B-6)
Zinc
Dissolved
0.356
0.0142
Leviathan Mine, Semi-
Passive, Alkaline
Lagoon
U.S. EPA, 2006a
(Table B-6)
Iron
Total
850.57 ± 239.84
8.92 ± 20.41
Elizabeth Mine
Butler and
Hathaway, 2020
(Table 1)
2009 Average
Iron
Total
858.45 ±189.55
0.52 ±0.59
Elizabeth Mine
Butler and
Hathaway, 2020
(Table 1)
2010 Average
Iron
Total
856.24 ± 126.83
1.98 ±6.85
Elizabeth Mine
Butler and
Hathaway, 2020
(Table 1)
2011 Average
Iron
Total
879.55 ± 181.09
0.37 ±0.29
Elizabeth Mine
Butler and
Hathaway, 2020
(Table 1)
2012 Average
Iron
Total
461.65 ± 74.47
0.24 ±0.58
Elizabeth Mine
Butler and
Hathaway, 2020
(Table 1)
2013 Average
Iron
Total
309.32 ± 51.68
0.35 ± 1.01
Elizabeth Mine
Butler and
Hathaway, 2020
(Table 1)
2014 Average
Iron
Total
214.35 ±96.21
1.61 ± 11.05
Elizabeth Mine
Butler and
Hathaway, 2020
(Table 1)
2015 Average
Iron
Total
183.62 ± 53.93
10.46 ±
17.95
Elizabeth Mine
Butler and
Hathaway, 2020
(Table 1)
2016 Average
Iron
Total
199.15 ±64.75
12.28 ±
12.74
Elizabeth Mine
Butler and
Hathaway, 2020
(Table 1)
2017 Average
C-7
-------
Appendix C: Neutralization and Chemical Precipitation Data Tables
Table C-2: Average Influent and Effluent Concentrations - All Applicable Case Studies
Constituent
Water Sample
Average Influent
Average
Effluent
Mine
Source
Notes
Aluminum
Dissolved
21
0.5
Britannia Mine
Madsen et al.,
2012
(Tables 2 and 7)
2006 Average3,15
Aluminum
Dissolved
19
0.5
Britannia Mine
Madsen et al.,
2012
(Tables 2 and 7)
2007 Averagea d
Aluminum
Dissolved
16
0.5
Britannia Mine
Madsen et al.,
2012
(Tables 2 and 7)
2008 Average36
Aluminum
Dissolved
19
0.4
Britannia Mine
Madsen et al.,
2012
(Tables 2 and 7)
2009 Average3 '
Aluminum
Dissolved
19
0.5
Britannia Mine
Madsen et al.,
2012
(Tables 2 and 7)
2010 Average3,8
Cadmium
Dissolved
0.09
0.002
Britannia Mine
Madsen et al.,
2012
(Tables 2 and 7)
2006 Average3 b
Cadmium
Dissolved
0.097
0.001
Britannia Mine
Madsen et al.,
2012
(Tables 2 and 7)
2007 Average3 d
Cadmium
Dissolved
0.085
0.001
Britannia Mine
Madsen et al.,
2012
(Tables 2 and 7)
2008 Average36
Cadmium
Dissolved
0.087
0.001
Britannia Mine
Madsen et al.,
2012
(Tables 2 and 7)
2009 Average3 '
Cadmium
Dissolved
0.087
0.001
Britannia Mine
Madsen et al.,
2012
(Tables 2 and 7)
2010 Average3,8
Copper
Dissolved
17
0.01
Britannia Mine
Madsen et al.,
2012
(Tables 2 and 7)
2006 Average3 b
C-8
-------
Appendix C: Neutralization and Chemical Precipitation Data Tables
Table C-2: Average Influent and Effluent Concentrations - All Applicable Case Studies
Constituent
Water Sample
Average Influent
Average
Effluent
Mine
Source
Notes
Copper
Dissolved
16.8
0.01
Britannia Mine
Madsen et al.,
2012
(Tables 2 and 7)
2007 Averagea d
Copper
Dissolved
13.9
0.02
Britannia Mine
Madsen et al.,
2012
(Tables 2 and 7)
2008 Average36
Copper
Dissolved
15.8
<0.01
Britannia Mine
Madsen et al.,
2012
(Tables 2 and 7)
2009 Average3 '
Copper
Dissolved
13.9
<0.01
Britannia Mine
Madsen et al.,
2012
(Tables 2 and 7)
2010 Average3,8
Iron
Dissolved
1.7
0.01
Britannia Mine
Madsen et al.,
2012
(Tables 2 and 7)
2006 Average3 b
Iron
Dissolved
0.75
0.05
Britannia Mine
Madsen et al.,
2012
(Tables 2 and 7)
2007 Average3 d
Iron
Dissolved
0.7
0.01
Britannia Mine
Madsen et al.,
2012
(Tables 2 and 7)
2008 Average36
Iron
Dissolved
0.75
0.01
Britannia Mine
Madsen et al.,
2012
(Tables 2 and 7)
2009 Average3 '
Iron
Dissolved
0.95
<0.01
Britannia Mine
Madsen et al.,
2012
(Tables 2 and 7)
2010 Average38
Manganese
Dissolved
4.8
0.3
Britannia Mine
Madsen et al.,
2012
(Tables 2 and 7)
2006 Average3 b
Manganese
Dissolved
4.3
0.1
Britannia Mine
Madsen et al.,
2012
(Tables 2 and 7)
2007 Average3 d
C-9
-------
Appendix C: Neutralization and Chemical Precipitation Data Tables
Table C-2: Average Influent and Effluent Concentrations - All Applicable Case Studies
Constituent
Water Sample
Average Influent
Average
Effluent
Mine
Source
Notes
Manganese
Dissolved
3.5
0.3
Britannia Mine
Madsen et al.,
2012
(Tables 2 and 7)
2008 Average36
Manganese
Dissolved
4.1
0.4
Britannia Mine
Madsen et al.,
2012
(Tables 2 and 7)
2009 Average3 '
Manganese
Dissolved
3.9
0.4
Britannia Mine
Madsen et al.,
2012
(Tables 2 and 7)
2010 Average3,8
Zinc
Dissolved
20
0.02
Britannia Mine
Madsen et al.,
2012
(Tables 2 and 7)
2006 Average3 b
Zinc
Dissolved
19.7
0.03
Britannia Mine
Madsen et al.,
2012
(Tables 2 and 7)
2007 Average3 d
Zinc
Dissolved
14.8
0.04
Britannia Mine
Madsen et al.,
2012
(Tables 2 and 7)
2008 Average36
Zinc
Dissolved
17.7
0.03
Britannia Mine
Madsen et al.,
2012
(Tables 2 and 7)
2009 Average3 '
Zinc
Dissolved
18.7
0.03
Britannia Mine
Madsen et al.,
2012
(Tables 2 and 7)
2010 Average38
PH
NA
4.0
9.2°
Britannia Mine
Madsen et al.,
2012
(Tables 2 and 7)
2006 Average3 b
PH
NA
3.7
9.2
Britannia Mine
Madsen et al.,
2012
(Tables 2 and 7)
2007 Average3 d
PH
NA
3.8
9.2
Britannia Mine
Madsen et al.,
2012
(Tables 2 and 7)
2008 Average36
C-10
-------
Appendix C: Neutralization and Chemical Precipitation Data Tables
Table C-2: Average Influent and Effluent Concentrations - All Applicable Case Studies
Constituent
Water Sample
Average Influent
Average
Mine
Source
Notes
Effluent
PH
NA
4.1
9.2
Britannia Mine
Madsen et al.,
2009 Average3 '
2012
(Tables 2 and 7)
PH
NA
4.2
9.2
Britannia Mine
Madsen et al.,
2010 Average3,8
2012
(Tables 2 and 7)
Notes:
All analytical results reported in mg/L
pH results reported in standard units
NA- Not applicable
ND - Not detected
Leviathan data calculated from data in Appendix B in U.S. EPA, 2006a. Dual-stage data come from 12 sampling dates in 2002 and 1 in 2003 and the single-
stage data comes from 7 sampling dates in 2003; and the semi-passive results are from 8 samples collected in 2002.
Data from Butler and Hathaway, 2020, include average concentrations and standard deviations
a = Average influent concentration (C3) calculated from average mine workings concentrations (CI) and volume (VI) and average groundwater
concentrations (C2) and volume (V2) via this equation: (V1C1 + V2C2)/(V1+V2) = C3.
b = 2006 combined influent volume = 3,923,000,000 liters
c = Madsen et al., 2012 (page 10):
"WTP discharge water pH is consistently 9.2"
d = 2007 combined influent volume = 5,256,400,000 L
e = 2008 combined influent volume = 3,836,200,000 L
f = 2009 combined influent volume = 3,370,700,000 L
g = 2010 combined influent volume = 4,424,400,000 L
Non-detect values were adjusted to Yi the detection limit for calculations
C-ll
-------
Appendix C: Neutralization and Chemical Precipitation Data Tables
Table C-3: Average Mass Treated and Average Mass Removed per Year - Britannia Mine
Constituent
Water
Sample
Average Mass
T reated3
Average Mass Removed13
Mine
Source
Year
Aluminum
Dissolved
83,005
81,043
Britannia
Mine
Madsen et al., 2012
2006°
Aluminum
Dissolved
100,589
97,960
Britannia
Mine
Madsen et al., 2012
2007d
Aluminum
Dissolved
61,677
59,759
Britannia
Mine
Madsen et al., 2012
2008e
Aluminum
Dissolved
65,060
63,712
Britannia
Mine
Madsen et al., 2012
2009f
Aluminum
Dissolved
85,399
83,187
Britannia
Mine
Madsen et al., 2012
20108
Cadmium
Dissolved
354
346
Britannia
Mine
Madsen et al., 2012
2006°
Cadmium
Dissolved
508
503
Britannia
Mine
Madsen et al., 2012
2007d
Cadmium
Dissolved
326
323
Britannia
Mine
Madsen et al., 2012
2008e
Cadmium
Dissolved
293
289
Britannia
Mine
Madsen et al., 2012
2009f
Cadmium
Dissolved
384
380
Britannia
Mine
Madsen et al., 2012
20108
Copper
Dissolved
65,862
65,823
Britannia
Mine
Madsen et al., 2012
2006°
Copper
Dissolved
88,319
88,267
Britannia
Mine
Madsen et al., 2012
2007d
Copper
Dissolved
53,179
53,102
Britannia
Mine
Madsen et al., 2012
2008e
Copper
Dissolved
53,199
53,182
Britannia
Mine
Madsen et al., 2012
2009f
Copper
Dissolved
61,329
61,307
Britannia
Mine
Madsen et al., 2012
20106
Iron
Dissolved
6,623
6,584
Britannia
Mine
Madsen et al., 2012
2006°
C-12
-------
Appendix C: Neutralization and Chemical Precipitation Data Tables
Table C-3: Average Mass Treated and Average Mass Removed per Year - Britannia Mine
Constituent
Water
Sample
Average Mass
T reated3
Average Mass Removed13
Mine
Source
Year
Iron
Dissolved
3,963
3,700
Britannia
Mine
Madsen et al., 2012
2007d
Iron
Dissolved
2,532
2,494
Britannia
Mine
Madsen et al., 2012
2008e
Iron
Dissolved
2,513
2,480
Britannia
Mine
Madsen et al., 2012
2009f
Iron
Dissolved
4,220
4,198
Britannia
Mine
Madsen et al., 2012
20108
Manganese
Dissolved
18,870
17,694
Britannia
Mine
Madsen et al., 2012
2006°
Manganese
Dissolved
22,770
22,244
Britannia
Mine
Madsen et al., 2012
2007d
Manganese
Dissolved
13,248
12,097
Britannia
Mine
Madsen et al., 2012
2008e
Manganese
Dissolved
13,882
12,534
Britannia
Mine
Madsen et al., 2012
2009f
Manganese
Dissolved
17,430
15,660
Britannia
Mine
Madsen et al., 2012
20108
Zinc
Dissolved
77,320
77,242
Britannia
Mine
Madsen et al., 2012
2006°
Zinc
Dissolved
103,706
103,548
Britannia
Mine
Madsen et al., 2012
2007d
Zinc
Dissolved
56,844
56,690
Britannia
Mine
Madsen et al., 2012
2008e
Zinc
Dissolved
59,727
59,626
Britannia
Mine
Madsen et al., 2012
2009f
Zinc
Dissolved
82,850
82,718
Britannia
Mine
Madsen et al., 2012
20106
Notes:
Results reported in kilograms (kg)
a = Average mass (M) calculated from average mine workings concentrations (CI) and yearly volume (VI) and average groundwater concentrations (C2)
and yearly groundwater volume (V2) via this equation: (V1C1 + V2C2) = M
C-13
-------
Appendix C: Neutralization and Chemical Precipitation Data Tables
Table C-3: Average Mass Treated and Average Mass Removed per Year - Britannia Mine
Constituent
Water
Sample
Average Mass
T reated3
Average Mass Removed13
Mine
Source
Year
b = Average mass removed (M2) calculated from average mass (M) and average effluent concentrations (C4) and combined influent volume (V3) via this
equation: M - (C4V3) = M2
c = 2006 combined influent volume = 3,923,000,000 L
d = 2007 combined influent volume = 5,256,400,000 L
e = 2008 combined influent volume = 3,836,200,000 L
f = 2009 combined influent volume = 3,370,700,000 L
g = 2010 combined influent volume = 4,424,400,000 L
Non-detect values were adjusted to Vi the detection limit for calculations
C-14
-------
Appendix C: Neutralization and Chemical Precipitation Data Tables
Table C-4: Removal Efficiencies - All Applicable Sites
Constituent
Average Removal
Efficiency
Maximum
Minimum
Mine
Source
Aluminum
99.5%
99.8%
99%
Leviathan Mine, Active, Single-
stage
U.S. EPA, 2006a
(Table 1-2)
Arsenic
99.8%
99.9%
99.7%
Leviathan Mine, Active, Single-
stage
U.S. EPA, 2006a
(Table 1-2)
Cadmium
99.1%
99.7%
98.4%
Leviathan Mine, Active, Single-
stage
U.S. EPA, 2006a
(Table 1-2)
Chromium
99.0%
99.8%
95.6%
Leviathan Mine, Active, Single-
stage
U.S. EPA, 2006a
(Table 1-2)
Copper
99.4%
99.7%
99%
Leviathan Mine, Active, Single-
stage
U.S. EPA, 2006a
(Table 1-2)
Iron
100.0%
100%
99.9%
Leviathan Mine, Active, Single-
stage
U.S. EPA, 2006a
(Table 1-2)
Lead
74.6%
89.8%
48.3%
Leviathan Mine, Active, Single-
stage
U.S. EPA, 2006a
(Table 1-2)
Nickel
97.9%
99.3%
95.7%
Leviathan Mine, Active, Single-
stage
U.S. EPA, 2006a
(Table 1-2)
Selenium
93.1%
94.4%
91%
Leviathan Mine, Active, Single-
stage
U.S. EPA, 2006a
(Table 1-2)
Zinc
98.9%
99.6%
97.7%
Leviathan Mine, Active, Single-
stage
U.S. EPA, 2006a
(Table 1-2)
Aluminum
99.7%
99.9%
99.2%
Leviathan Mine, Active, Dual-
stage
U.S. EPA, 2006a
(Table 1-1)
Arsenic
99.6%
99.8%
99.2%
Leviathan Mine, Active, Dual-
stage
U.S. EPA, 2006a
(Table 1-1)
Cadmium
98.7%
99.4%
97.5%
Leviathan Mine, Active, Dual-
stage
U.S. EPA, 2006a
(Table 1-1)
Chromium
99.3%
99.9%
93.8%
Leviathan Mine, Active, Dual-
stage
U.S. EPA, 2006a
(Table 1-1)
Copper
99.7%
99.8%
99.4%
Leviathan Mine, Active, Dual-
stage
U.S. EPA, 2006a
(Table 1-1)
Iron
100%
100%
99.9%
Leviathan Mine, Active, Dual-
stage
U.S. EPA, 2006a
(Table 1-1)
C-15
-------
Appendix C: Neutralization and Chemical Precipitation Data Tables
Table C-4: Removal Efficiencies - All Applicable Sites
Constituent
Average Removal
Efficiency
Maximum
Minimum
Mine
Source
Lead
78.3%
86.7%
69.2%
Leviathan Mine, Active, Dual-
stage
U.S. EPA, 2006a
(Table 1-1)
Nickel
99.5%
99.9%
99.2%
Leviathan Mine, Active, Dual-
stage
U.S. EPA, 2006a
(Table 1-1)
Zinc
98.7%
99.4%
97.4%
Leviathan Mine, Active, Dual-
stage
U.S. EPA, 2006a
(Table 1-1)
Aluminum
99.2%
99.5%
98%
Leviathan Mine, Semi-Passive,
Alkaline Lagoon
U.S. EPA, 2006a
(Tables 1-3 and 2-4)
Arsenic
98.9%
99.5%
97.6%
Leviathan Mine, Semi-Passive,
Alkaline Lagoon
U.S. EPA, 2006a
(Tables 1-3 and 2-4)
Chromium
88.5%
92.3%
83.1%
Leviathan Mine, Semi-Passive,
Alkaline Lagoon
U.S. EPA, 2006a
(Tables 1-3 and 2-4)
Copper
58.3%
74.5%
27.7%
Leviathan Mine, Semi-Passive,
Alkaline Lagoon
U.S. EPA, 2006a
(Tables 1-3 and 2-4)
Iron
100%
100%
99.9%
Leviathan Mine, Semi-Passive,
Alkaline Lagoon
U.S. EPA, 2006a
(Tables 1-3 and 2-4)
Lead
66.4%
78.9%
37.7%
Leviathan Mine, Semi-Passive,
Alkaline Lagoon
U.S. EPA, 2006a
(Tables 1-3 and 2-4)
Nickel
98.6%
99.1%
97.2%
Leviathan Mine, Semi-Passive,
Alkaline Lagoon
U.S. EPA, 2006a
(Tables 1-3 and 2-4)
Zinc
96.0%
98.2%
90.6%
Leviathan Mine, Semi-Passive,
Alkaline Lagoon
U.S. EPA, 2006a
(Tables 1-3 and 2-4)
Iron
98.43%
99.96%
93.83%
Elizabeth Mineb
Butler and
Hathaway, 2020
Aluminum
97.5%
97.9%
96.9%
Britannia Mine0
Madsen et al., 2012
Cadmium
98.7%
99.0%
97.8%
Britannia Mine0
Madsen et al., 2012
Copper
99.9%
100.0%
99.9%
Britannia Mine0
Madsen et al., 2012
Iron
97.9%
99.5%
93.4%
Britannia Mine0
Madsen et al., 2012
Manganese
92.6%
97.7%
89.8%
Britannia Mine0
Madsen et al., 2012
Zinc
99.8%
99.9%
99.7%
Britannia Mine0
Madsen et al., 2012
Notes:
C-16
-------
Appendix C: Neutralization and Chemical Precipitation Data Tables
Table C-4: Removal Efficiencies - All Applicable Sites
Constituent
Average Removal
Efficiency
Maximum
Minimum
Mine
Source
For Leviathan Mine, Dual-stage data come from 12 sampling dates in 2002 and 1 in 2003 and the Single-stage comes from 7 sampling dates in 2003; and the
semi-passive results are from 8 samples collected in 2002
a = EPA calculated the average removal efficiencies across 2006-2010 by determining the average removal efficiencies for each year and then averaging
those values
b = EPA calculated maximum and minimum removal efficiencies from yearly average influent and effluent concentrations from 2009 to 2017
c = EPA calculated maximum and minimum removal efficiencies from yearly average influent and effluent concentrations from 2006 to 2010
Non-detect values were adjusted to % the detection limit in calculation
C-17
-------
Appendix D: Constructed Wetlands Data Tables
Appendix D: Constructed Wetlands Data Tables
Table D-l: Average Influent and Effluent Concentrations - All Applicable Case Studies
Constituent
Water
Sample
Average
Influent
Average
Effluent
Timeframe
Mine - Wetland
Source
Notes
>
\erobic
Cobalt
NS
0.036
0.008
1992 to 1994
Dunka Mine -
WlDa
Eger and
Eger, 2005
Table 1
Cobalt
NS
0.036
0.008
1992 to 1997
Dunka Mine -
W1D
ITRC, 2010
Table 2-2
Cobalt
NS
0.009
0.001
1996 to 1998
Dunka Mine -
WlDa
Eger and
Eger, 2005
Table 1
Copper
NS
0.068
0.008
1992 to 1994
Dunka Mine -
WlDa
Eger and
Eger, 2005
Table 1
Copper
NS
0.068
0.010
1992 to 1997
Dunka Mine -
W1D
ITRC, 2010
Table 2-2
Copper
NS
0.03
0.003
1996 to 1998
Dunka Mine -
WlDa
Eger and
Eger, 2005
Table 1
Copper
NS
0.02
0.002
1999 to 2004
Dunka Mine -
WlDa
Eger and
Eger, 2005
Table 1
Nickel
NS
3.98
0.36
1992 to 1994
Dunka Mine -
WlDa
Eger and
Eger, 2005
Table 1
Nickel
NS
3.98
0.700
1992 to 1997
Dunka Mine -
W1D
ITRC, 2010
Table 2-2
Nickel
NS
0.74
0.19
1996 to 1998
Dunka Mine -
WlDa
Eger and
Eger, 2005
Table 1
Nickel
NS
0.76
0.1
1999 to 2004
Dunka Mine -
WlDa
Eger and
Eger, 2005
Table 1
PH
NA
7.07
7.18
1992 to 1994
Dunka Mine -
WlDa
Eger and
Eger, 2005
Table 1
PH
NA
7.07
7.18
1992 to 1997
Dunka Mine -
W1D
ITRC, 2010
Table 2-2
PH
NA
7.30
7.48
1996 to 1998
Dunka Mine -
WlDa
Eger and
Eger, 2005
Table 1
D-l
-------
Appendix D: Constructed Wetlands Data Tables
Table D-l: Average Influent and Effluent Concentrations - All Applicable Case Studies
Constituent
Water
Sample
Average
Influent
Average
Effluent
Timeframe
Mine - Wetland
Source
Notes
PH
NA
7.26
7.34
1999 to 2004
Dunka Mine -
WlDa
Eger and
Eger, 2005
Table 1
Zinc
NS
0.052
0.013
1992 to 1994
Dunka Mine -
WlDa
Eger and
Eger, 2005
Table 1
Zinc
NS
0.052
0.013
1992 to 1997
Dunka Mine -
W1D
ITRC, 2010
Table 2-2
Zinc
NS
0.021
0.006
1996 to 1998
Dunka Mine -
WlDa
Eger and
Eger, 2005
Table 1
Zinc
NS
0.019
0.006
1999 to 2004
Dunka Mine -
WlDa
Eger and
Eger, 2005
Table 1
Cobalt
NS
0.023
0.001
1995 to 1997
Dunka Mine -
W1D Expanded
ITRC, 2010
Table 2-2
Cobalt
NS
0.009
0.001
1996 to 1999
Dunka Mine -
W1D Expanded
Eger and
Eger, 2005
Table 1
Copper
NS
0.059
0.005
1995 to 1997
Dunka Mine -
W1D Expanded
ITRC, 2010
Table 2-2
Copper
NS
0.03
0.005
1996 to 1999
Dunka Mine -
W1D Expanded
Eger and
Eger, 2005
Table 1
Copper
NS
0.02
0.002
1999 to 2004
Dunka Mine -
W1D Expanded
Eger and
Eger, 2005
Table 1
Nickel
NS
1.200
0.180
1995 to 1997
Dunka Mine -
W1D Expanded
ITRC, 2010
Table 2-2
Nickel
NS
0.74
0.18
1996 to 1999
Dunka Mine -
W1D Expanded
Eger and
Eger, 2005
Table 1
Nickel
NS
0.76
0.099
1999 to 2004
Dunka Mine -
W1D Expanded
Eger and
Eger, 2005
Table 1
PH
NA
7.1
7.38
1995 to 1997
Dunka Mine -
W1D Expanded
ITRC, 2010
Table 2-2
PH
NA
7.3
7.38
1996 to 1999
Dunka Mine -
W1D Expanded
Eger and
Eger, 2005
Table 1
PH
NA
7.26
7.37
1999 to 2004
Dunka Mine -
W1D Expanded
Eger and
Eger, 2005
Table 1
D-2
-------
Appendix D: Constructed Wetlands Data Tables
Table D-l: Average Influent and Effluent Concentrations - All Applicable Case Studies
Constituent
Water
Sample
Average
Influent
Average
Effluent
Timeframe
Mine - Wetland
Source
Notes
Zinc
NS
0.017
0.011
1995 to 1997
Dunka Mine -
W1D Expanded
ITRC, 2010
Table 2-2
Zinc
NS
0.0216
0.011
1996 to 1999
Dunka Mine -
W1D Expanded
Eger and
Eger, 2005
Table 1
Zinc
NS
0.019
0.011
1999 to 2004
Dunka Mine -
W1D Expanded
Eger and
Eger, 2005
Table 1
PH
NA
7.1
7.38
1995 to 1997
Dunka Mine -
W1D Expanded
ITRC, 2010
Table 2-2
PH
NA
7.3
7.38
1996 to 1999
Dunka Mine -
W1D Expanded
Eger and
Eger, 2005
Table 1
PH
NA
7.26
7.37
1999 to 2004
Dunka Mine -
W1D Expanded
Eger and
Eger, 2005
Table 1
Anaerobic
Aluminum
Total
2.351
0.073
9/8/99 to
1/1/2002
Copper Basin
Mining District
Faulkner and
Miller, 2002
Table 4
Copper
Total
0.43
<0.025
10/1998 to
3/1999
Copper Basin
Mining District
Faulkner and
Miller, 2002
Table 4
Copper
Total
0.311
0.008
9/8/99 to
1/1/2002
Copper Basin
Mining District
Faulkner and
Miller, 2002
Table 4
Iron
Total
1.07
0.353
9/8/99 to
1/1/2002
Copper Basin
Mining District
Faulkner and
Miller, 2002
Table 4
Manganese
Total
1.52
1.64
9/8/99 to
1/1/2002
Copper Basin
Mining District
Faulkner and
Miller, 2002
Table 4
Sulfate
NA
142
128
9/8/99 to
1/1/2002
Copper Basin
Mining District
Faulkner and
Miller, 2002
Table 4
D-3
-------
Appendix D: Constructed Wetlands Data Tables
Table D-l: Average Influent and Effluent Concentrations - All Applicable Case Studies
Constituent
Water
Sample
Average
Influent
Average
Effluent
Timeframe
Mine - Wetland
Source
Notes
Zinc
Total
1.094
0.045
9/8/99 to
1/1/2002
Copper Basin
Mining District
Faulkner and
Miller, 2002
Table 4
PH
NA
4.2
7.1
9/8/99 to
1/1/2002
Copper Basin
Mining District15
Faulkner and
Miller, 2002
Table 4
Notes:
All analytical results reported in mg/L
pH results reported in standard units
NS = Not specified
NA = Not applicable
a = Figure 4 in Eger and Eger, 2005, shows inputs of "base metal input" and "base metal seep" in several locations downstream of the
wetland W1D influent monitoring station (WS-005); actual concentrations of influent to W1D may be higher than concentrations
reported in the reference
b = Base flow from McPherson Branch only
D-4
-------
Appendix D: Constructed Wetlands Data Tables
Table D-2: Removal Efficiencies - All Applicable Sites
Constituent
Water
Sample
Average Removal
Efficiency
Mine - Wetland
Source
Notes
Aerobic
Cobalt
NS
77.8%
Dunka Mine - W1D
Eger and Eger, 2005
(Table 1)
Calculated by EPA based on averages
presented for 1992 to 1994
Cobalt
NS
77.8%
Dunka Mine - W1D
ITRC, 2010
(Table 2-2)
Calculated by EPA based on averages
presented for 1992 to 1997
Cobalt
NS
88.9%
Dunka Mine - W1D
Eger and Eger, 2005
(Table 1)
Calculated by EPA based on averages
presented for 1996 to 1998
Copper
NS
88.2%
Dunka Mine - W1D
Eger and Eger, 2005
(Table 1)
Calculated by EPA based on averages
presented for 1992 to 1994
Copper
NS
85.3%
Dunka Mine - W1D
ITRC, 2010
(Table 2-2)
Calculated by EPA based on averages
presented for 1992 to 1997
Copper
NS
90.0%
Dunka Mine - W1D
Eger and Eger, 2005
(Table 1)
Calculated by EPA based on averages
presented for 1996 to 1998
Copper
NS
90.0%
Dunka Mine - W1D
Eger and Eger, 2005
(Table 1)
Calculated by EPA based on averages
presented for 1999 to 2004
Nickel
NS
91.0%
Dunka Mine - W1D
Eger and Eger, 2005
(Table 1)
Calculated by EPA based on averages
presented for 1992 to 1994
Nickel
NS
82.4%
Dunka Mine - W1D
ITRC, 2010
(Table 2-2)
Calculated by EPA based on averages
presented for 1992 to 1997
Nickel
NS
74.3%
Dunka Mine - W1D
Eger and Eger, 2005
(Table 1)
Calculated by EPA based on averages
presented for 1996 to 1998
Nickel
NS
86.8%
Dunka Mine - W1D
Eger and Eger, 2005
(Table 1)
Calculated by EPA based on averages
presented for 1999 to 2004
Zinc
NS
75.0%
Dunka Mine - W1D
Eger and Eger, 2005
(Table 1)
Calculated by EPA based on averages
presented for 1992 to 1994
Zinc
NS
75.0%
Dunka Mine - W1D
ITRC, 2010
(Table 2-2)
Calculated by EPA based on averages
presented for 1992 to 1997
Zinc
NS
71.4%
Dunka Mine - W1D
Eger and Eger, 2005
(Table 1)
Calculated by EPA based on averages
presented for 1996 to 1998
Zinc
NS
68.4%
Dunka Mine - W1D
Eger and Eger, 2005
(Table 1)
Calculated by EPA based on averages
presented for 1999 to 2004
Cobalt
NS
95.7%
Dunka Mine-W1D
Expanded
ITRC, 2010
(Table 2-2)
Calculated by EPA based on averages
presented for 1995 to 1997
D-5
-------
Appendix D: Constructed Wetlands Data Tables
Table D-2: Removal Efficiencies - All Applicable Sites
Constituent
Water
Sample
Average Removal
Efficiency
Mine - Wetland
Source
Notes
Cobalt
NS
88.9%
Dunka Mine-W1D
Expanded
Eger and Eger, 2005
(Table 1)
Calculated by EPA based on averages
presented for 1996 to 1999
Copper
NS
91.5%
Dunka Mine-W1D
Expanded
ITRC, 2010
(Table 2-2)
Calculated based on averages presented for
1995 to 1997
Copper
NS
83.3%
Dunka Mine-W1D
Expanded
Eger and Eger, 2005
(Table 1)
Calculated by EPA based on averages
presented for 1996 to 1999
Copper
NS
90.0%
Dunka Mine-W1D
Expanded
Eger and Eger, 2005
(Table 1)
Calculated by EPA based on averages
presented for 1999 to 2004
Nickel
NS
85.0%
Dunka Mine-W1D
Expanded
ITRC, 2010
(Table 2-2)
Calculated by EPA based on averages
presented for 1995 to 1997
Nickel
NS
75.7%
Dunka Mine-W1D
Expanded
Eger and Eger, 2005
(Table 1)
Calculated by EPA based on averages
presented for 1996 to 1999
Nickel
NS
87.0%
Dunka Mine-W1D
Expanded
Eger and Eger, 2005
(Table 1)
Calculated by EPA based on averages
presented for 1999 to 2004
Zinc
NS
35.3%
Dunka Mine-W1D
Expanded
ITRC, 2010
(Table 2-2)
Calculated by EPA based on averages
presented for 1995 to 1997
Zinc
NS
49.1%
Dunka Mine-W1D
Expanded
Eger and Eger, 2005
(Table 1)
Calculated by EPA based on averages
presented for 1996 to 1999
Zinc
NS
42.1%
Dunka Mine-W1D
Expanded
Eger and Eger, 2005
(Table 1)
Calculated by EPA based on averages
presented for 1999 to 2004
Anaerobic
Aluminum
Total
96.9%
Copper Basin Mining
District
Faulkner and Miller, 2002
(Table 4)
Calculated by EPA based on averages
presented for 9/8/99 to 1/1/2002
Copper
Total
97.4%
Copper Basin Mining
District
Faulkner and Miller, 2002
(Table 4)
Calculated by EPA based on averages
presented for 9/8/99 to 1/1/2002
Copper
Total
94.2%
Copper Basin Mining
District
Faulkner and Miller, 2002
(Table 4)
Calculated by EPA based on averages
presented for 10/1998-3/1999; assumed
average effluent of 0.025 mg/La
Iron
Total
67.0%
Copper Basin Mining
District
Faulkner and Miller, 2002
(Table 4)
Calculated by EPA based on averages
presented for 9/8/99 to 1/1/2002
Manganese
Total
-7.9%
Copper Basin Mining
District
Faulkner and Miller, 2002
(Table 4)
Calculated by EPA based on averages
presented for 9/8/99 to 1/1/2002
D-6
-------
Appendix D: Constructed Wetlands Data Tables
Table D-2: Removal Efficiencies - All Applicable Sites
Constituent
Water
Sample
Average Removal
Efficiency
Mine - Wetland
Source
Notes
Sulfate
NS
9.9%
Copper Basin Mining
District
Faulkner and Miller, 2002
(Table 4)
Calculated by EPA based on averages
presented for 9/8/99 to 1/1/2002
Zinc
Total
95.9%
Copper Basin Mining
District
Faulkner and Miller, 2002
(Table 4)
Calculated by EPA based on averages
presented for 9/8/99 to 1/1/2002
Notes:
NS - Not specified
a = Reference stated, "average influent copper concentration was reduced from 0.43 mg/Lto less than 0.025 mg/L in the effluent"; therefore, 0.025 mg/L
was used to enable calculation
D-7
-------
Appendix E: Treatment Trains Data Tables
Appendix E: Treatment Trains Data Tables
Table E-l: Maximum and Minimum Influent and Corresponding Effluent Concentrations - Calliope Mine
Constituent
Influent
Flow3
Maximum
Influent
Corresponding
Effluent
Influent
Flow"
Minimum
Influent
Corresponding
Effluent
Notes
Aluminum
3.85xl0"5
14.1
0.0138
6.16xl0"5
0.011
0.0165
BCR II effluent
Arsenic
5.53xl0"5
0.0109
0.0054
5.80xl0"5
0.0011
0.004
BCR II effluent
Cadmium
3.85xl0"5
0.0419
0.0048
5.57x10 s
0.0028
0.0001
BCR II effluent
Copper
3.85xl0"5
3.05
0.0078
5.14xl0"5
0.0028
0.0237
BCR II effluent
Iron
3.85xl0"5
7.22
0.0975
5.57x10 s
0.008
0.110
BCR II effluent
Manganese
3.85xl0"5
3.77
0.551
5.57x10 s
0.690
0.600
BCR II effluent
Sulfate
3.85xl0"5
229
281
5.57x10 s
60.6
8
BCR II effluent
Zinc
3.85xl0"5
11.1
0.249
5.57x10 s
0.990
0.048
BCR II effluent
PH
5.14xl0"5
7.52
7.21
3.85xl0"5
3.29
8.29
BCR II effluent
Aluminum
5.03xl0"5
2.4
0.0542
1.07xl0"4
0.0173
0.0173
BCR IV effluent
Arsenic
3.39xl0"5
0.0067
0.0034
5.79xl0"5
6.23xl0"5
0.0011
0.0011
0.0041
0.0011
BCR IV effluent
Cadmium
3.07xl0"5
0.0179
0.0039
1.59xl0"4
0.0037
0.0034
BCR IV effluent
Copper
5.03xl0"5
0.884
0.103
8.06xl0"5
0.0442
0.0529
BCR IV effluent
Iron
5.03xl0"5
0.524
0.417
1.59xl0"4
1.29xl0"4
0.0155
0.0155
0.0671
0.124
BCR IV effluent
Manganese
3.07xl0"5
6.38xl0"5
1.95
1.95
1.07
1.48
1.07xl0"4
1.07
0.837
BCR IV effluent
Sulfate
5.43xl0"5
122
326
8.06xl0"5
69.8
84.7
BCR IV effluent
Zinc
3.07xl0"5
3.79
0.672
8.06xl0"5
1.42
0.383
BCR IV effluent
E-l
-------
Appendix E: Treatment Trains Data Tables
Table E-l: Maximum and Minimum Influent and Corresponding Effluent Concentrations - Calliope Mine
Constituent
Influent
Flow3
Maximum
Influent
Corresponding
Effluent
Influent
Flowb
Minimum
Influent
Corresponding
Effluent
Notes
PH
8.06x10
,-5
7.08
7.57
5.03x10
1-5
3.87
9.98
BCR IV effluent
Notes:
Source: Wilmoth, 2002 (Tables 5-1 and 5-2 (pH), 5-4 (sulfate) and 5-6 (all other constituents)
All analytical results reported in mg/l
All flow reported in cubic meters per second (converted from gallons per minute)
pH results reported in standard units
All constituent concentrations reported as total
a = Influent flow rate from same date as maximum influent concentration, as reported in Table 4-la, Wilmoth, 2002
b = Influent flow rate from same date as minimum influent concentration, as reported in Table 4-la, Wilmoth, 2002
c = Wilmoth, 2002 reported this value as an outlier
The aboveground BCR (IV) reports no flow (0) during winter months; the BCR was designed to be shut down for winter
Table E-2: Maximum and Minimum Influent and Corresponding Effluent Concentrations - Force Crag
Constituent
Maximum
Corresponding
Minimum
Corresponding
Notes
Influent
Effluent
Influent
Effluent
Zinc
4.5
0.14
2.5
0.08
Figure 2
Notes:
Source: Jarvis et al., 2015
All analytical results in mg/L
All values reported as dissolved
E-2
-------
Appendix E: Treatment Trains Data Tables
Table E-3: Influent and Effluent Concentrations - Golden Sunlight Mine
Constituent
Influent
Effluent
Notes
Aluminum
1,740
0.126
Data originated from Table 4, collected March
12, 2003
Copper
81.4
0.001
Data originated from Table 4, collected March
12, 2003
Iron
198
2.62
Data originated from Table 4, collected March
12, 2003
Manganese
117
67.8
Data originated from Table 4, collected March
12, 2003
Zinc
39.5
0.011
Data originated from Table 4, collected March
12, 2003
Notes:
Source: Bless, 2008
All analytical results in mg/L
All constituent concentrations reported as dissolved
Table E-4: Influent and Effluent Concentrations - Leviathan Mine
Constituent
Water Sample
System Influent
Corresponding
System Effluent
Mode
Notes
Aluminum
Dissolved
36.9
0.144
Gravity mode
Data extracted
from Table 2-13
Aluminum
Total
36.4
0.468
Gravity mode
Data extracted
from Table 2-17
Aluminum
Dissolved
40.4
0.105
Recirculation mode
Data extracted
from Table 2-15
Aluminum
Total
40.4
0.120
Recirculation mode
Data extracted
from Table 2-18
Arsenic
Dissolved
0.0028
0.0024
Gravity mode
Data extracted
from Table 2-13
Arsenic
Total
0.0042
<0.0022
Gravity mode
Data extracted
from Table 2-17
Arsenic
Dissolved
<0.0021
0.0147
Recirculation mode
Data extracted
from Table 2-15
E-3
-------
Appendix E: Treatment Trains Data Tables
Table E-4: Influent and Effluent Concentrations - Leviathan Mine
Constituent
Water Sample
System Influent
Corresponding
System Effluent
Mode
Notes
Arsenic
Total
<0.0021
0.0149
Recirculation mode
Data extracted
from Table 2-18
Cadmium
Dissolved
0.0004
<0.00023
Gravity mode
Data extracted
from Table 2-13
Cadmium
Total
0.00041
<0.00023
Gravity mode
Data extracted
from Table 2-17
Cadmium
Dissolved
0.00094
<0.00016
Recirculation mode
Data extracted
from Table 2-15
Cadmium
Total
0.0011
<0.00016
Recirculation mode
Data extracted
from Table 2-18
Chromium
Dissolved
0.0172
0.0064
Gravity mode
Data extracted
from Table 2-13
Chromium
Total
0.0164
0.008
Gravity mode
Data extracted
from Table 2-17
Chromium
Dissolved
0.0193
0.0116
Recirculation mode
Data extracted
from Table 2-15
Chromium
Total
0.0198
0.0132
Recirculation mode
Data extracted
from Table 2-18
Copper
Dissolved
0.656
0.0056
Gravity mode
Data extracted
from Table 2-13
Copper
Total
0.647
0.0078
Gravity mode
Data extracted
from Table 2-17
Copper
Dissolved
0.766
0.0095
Recirculation mode
Data extracted
from Table 2-15
Copper
Total
0.757
0.0079
Recirculation mode
Data extracted
from Table 2-18
Iron
Dissolved
113
0.389
Gravity mode
Data extracted
from Table 2-13
Iron
Total
113
1.66
Gravity mode
Data extracted
from Table 2-17
Iron
Dissolved
99.5
0.269
Recirculation mode
Data extracted
from Table 2-15
Iron
Total
99.1
0.532
Recirculation mode
Data extracted
from Table 2-18
E-4
-------
Appendix E: Treatment Trains Data Tables
Table E-4: Influent and Effluent Concentrations - Leviathan Mine
Constituent
Water Sample
System Influent
Corresponding
System Effluent
Mode
Notes
Lead
Dissolved
0.0053
0.0034
Gravity mode
Data extracted
from Table 2-13
Lead
Total
0.0049
0.0029
Gravity mode
Data extracted
from Table 2-17
Lead
Dissolved
0.0059
0.0031
Recirculation mode
Data extracted
from Table 2-15
Lead
Total
0.0072
0.0065
Recirculation mode
Data extracted
from Table 2-18
Nickel
Dissolved
0.481
0.0531
Gravity mode
Data extracted
from Table 2-13
Nickel
Total
0.478
0.0715
Gravity mode
Data extracted
from Table 2-17
Nickel
Dissolved
0.531
0.0189
Recirculation mode
Data extracted
from Table 2-15
Nickel
Total
0.529
0.0224
Recirculation mode
Data extracted
from Table 2-18
Selenium
Dissolved
0.0096
0.0087
Gravity mode
Data extracted
from Table 2-13
Selenium
Total
0.0122
0.0052
Gravity mode
Data extracted
from Table 2-17
Selenium
Dissolved
0.0144
0.0078
Recirculation mode
Data extracted
from Table 2-15
Selenium
Total
0.0199
0.0108
Recirculation mode
Data extracted
from Table 2-18
Sulfate
Total
1,510
1,160
Gravity mode
Data extracted
from Table 2-9
Sulfate
Total
1,190
1,200
Recirculation mode
Data extracted
from Table 2-11
Zinc
Dissolved
0.702
0.0103
Gravity mode
Data extracted
from Table 2-13
Zinc
Total
0.692
0.0147
Gravity mode
Data extracted
from Table 2-17
Zinc
Dissolved
0.755
0.0045
Recirculation mode
Data extracted
from Table 2-15
E-5
-------
Appendix E: Treatment Trains Data Tables
Table E-4: Influent and Effluent Concentrations - Leviathan Mine
Constituent
Water Sample
System Influent
Corresponding
System Effluent
Mode
Notes
Zinc
Total
0.757
0.0106
Recirculation mode
Data extracted
from Table 2-18
PH
NA
3.1
7.7
Gravity mode
Data extracted
from Table 2-9
PH
NA
7.2
7.6
Recirculation mode
Data extracted
from Table 2-11
Notes:
Source: U.S. EPA, 2006a
All analytical results reported in mg/L
pH results reported in standard units
NA = not applicable
Leviathan gravity flow configuration data March 24, 2004; recirculation flow configuration data August 19, 2004
Table E-5: Maximum and Minimum Influent and Corresponding Effluent Concentrations - Standard Mine
Constituent
Maximum Influent
Corresponding APC
Effluent
Minimum Influent
Corresponding APC
Effluent
Notes
Cadmium
0.2
0.00006
0.085
0.00015
Data extracted from Figure 3
Copper
0.55
0.0015
0.011
0.0022
Data extracted from Figure 4
Iron
16
0.35
2
0.3
Data extracted from Figure 5
Lead
1.07
0.001
0.03
0.0007
Data extracted from Figure 6
Manganese
15
3
5.4
1
Data extracted from Figure 7
Zinc
30
0.033
14.9
1
Data extracted from Figure 8
Notes:
Source: Gallagher et al., 2012
All analytical results reported in mg/L
All constituent concentrations reported as dissolved except for iron, which was reported as total
E-6
-------
Appendix E: Treatment Trains Data Tables
Table E-5: Maximum and Minimum Influent and Corresponding Effluent Concentrations - Standard Mine
Constituent
Maximum Influent
Corresponding APC
Effluent
Minimum Influent
Corresponding APC
Effluent
Notes
Maximum and minimum influent selected from data points with corresponding APC effluent
APC = Aerobic Polishing Cell
Table E-6: Maximum and Minimum Influent and Corresponding Effluent Concentrations - Surething Mine
Constituent
Maximum
Influent
Corresponding
Effluent
Minimum
Influent
Corresponding
Effluent
Notes
Aluminum
29.5
<0.04
29.5
<0.04
Data from Table ES-1, one data point collected
September 1, 2005
Arsenic
1.25
<0.01
0.125
0.02
Data extracted from Figure 4-6, date range 2001
through 2005
Cadmium
0.385
0.005
0.04
<0.00009
Data extracted from Figure 4-3, date range 2001
through 2005
Copper
4.25
<0.003
0.5
<0.003
Data extracted from Figure 4-2, date range 2001
through 2005
Iron
51
<0.014
12
<0.014
Data extracted from Figure 4-5, date range 2001
through 2005
Manganese
26
<0.040
24
0.1
Data extracted from Figure 4-7, date range from
September through November2005, which reflects
upgrades to the aerobic BCR
Sulfate
900
120
50
170
Data extracted from Figure 4-14, date range from 2001
through 2005
Zinc
39
<0.007
4.5
<0.007
Data extracted from Figure 4-4, date range from 2001
through 2005.
PH
2.5
6.9
2.5
6.9
Data from Table ES-1, one data point collected
September 1, 2005
Notes:
Source: Nordwick and Bless, 2008
All analytical results reported in mg/L
pH results reported in standard units
All constituent concentrations reported as dissolved.
Detection limits inferred from Figure and the values provided in Table ES-1 in Nordwick and Bless, 2008.
E-7
-------
Appendix E: Treatment Trains Data Tables
Table E-7: Influent and Effluent Concentrations - Surething Mine
Constituent
Influent
Effluent
Aluminum
29.5
<0.04
Arsenic
0.127
<0.01
Cadmium
0.208
<0.00009
Copper
2.35
<0.003
Iron
15.0
<0.014
Lead
0.151
0.004
Manganese
26.7
0.037
Zinc
22.7
<0.007
Notes:
Source: Nordwick and Bless, 2008; Data from Table 4-2; collected September 1, 2005
All analytical results reported in mg/L
All constituent concentrations reported as dissolved
Table E-8: Influent and Effluent Concentrations - Wheal Jane Mine
Constituent
Influent
Effluent
Treatment
System
Notes
Iron
50
1
LD
Data extracted from Figure 4
Iron
67
<1
ALD
Data extracted from Figure 4
Iron
59
<1
LF
Data extracted from Figure 4
Zinc
31
11
LD
Data extracted from Figure 5
Zinc
33
14
ALD
Data extracted from Figure 5
Zinc
33
0.5
LF
Data extracted from Figure 5
Sulfate
238
333
LD
Data extracted from Figure 3
Sulfate
180
298
ALD
Data extracted from Figure 3
Sulfate
260
200
LF
Data extracted from Figure 3
ORP
360
730
LD
Data extracted from Figure 2
ORP
470
640
ALD
Data extracted from Figure 2
ORP
560
640
LF
Data extracted from Figure 2
PH
5.4
4.1
LD
Data extracted from Figure 2
PH
5
5
ALD
Data extracted from Figure 2
E-8
-------
Appendix E: Treatment Trains Data Tables
Table E-8: Influent and Effluent Concentrations - Wheal Jane Mine
Constituent
Influent
Effluent
Treatment
Notes
System
PH
3.9
6.7
LF
Data extracted from Figure 2
Notes:
Source: Johnson and Hallberg, 2005, based sampling conducted on September 19, 2002
The ALD became nonoperational in June 2000, after which the system operated as a second limestone-dosed
system.
All analytical results in mg/L; total or dissolved not specified
pH reported in standard units
LD = Limestone-dosed pre-treatment
ALD = Anoxic limestone drain
LF = Limestone-free system without pre-treatment
ORP = Oxidation-reduction potential
NA = not applicable
<1 = EPA could not determine concentration based on the data provided in the figure
Table E-9: Average Influent and Effluent Concentrations - Calliope Mine
Constituent
Average Influent
Average Effluent
Notes
Aluminum
1.2229
0.051703
BCR II effluent
Arsenic
<0.005
0.005894
BCR II effluent
Cadmium
0.01082
<0.005
BCR II effluent
Copper
0.4078
0.044064
BCR II effluent
Iron
0.4556
0.551436
BCR II effluent
Manganese
1.4581
0.786067
BCR II effluent
Sulfate
102.90
115.43
BCR II effluent
Zinc
2.8406
0.46329
BCR II effluent
PH
6.05
7.49
BCR II effluent
Aluminum
1.2229
0.0372
BCR IV effluent
Arsenic
0.5634
0.0070
BCR IV effluent
Cadmium
0.0103
0.0039
BCR IV effluent
Copper
0.2774
0.0347
BCR IV effluent
E-9
-------
Appendix E: Treatment Trains Data Tables
Table E-9: Average Influent and Effluent Concentrations - Calliope Mine
Constituent
Average Influent
Average Effluent
Notes
Iron
0.1556
0.4869
BCR IV effluent
Manganese
1.40
0.96
BCR IV effluent
Sulfate
97.5
111.9
BCR IV effluent
Zinc
2.54
0.36
BCR IV effluent
PH
5.84
7.74
BCR IV effluent
Notes:
Source: Wilmoth, 2002
All analytical results reported in mg/L
pH results reported in standard units
All constituent concentrations reported as total
EPA calculated average influent and effluent from constituent data reported in Table 5-2, 5-4 and 5-6 in
Wilmoth, 2002
Table E-10: Average Influent and Effluent Concentrations - Leviathan Mine
Constituent
Average Influent
Average Effluent
Mode
Notes
Aluminum
37.467
0.103
Gravity mode
Data from Table 2-2, based on 6
sampling events
Aluminum
40.209
0.0527
Recirculation mode
Data from Table 2-3, based on 7
sampling events
Arsenic
0.0021
0.0047
Gravity mode
Data from Table 2-2, based on 6
sampling events
Arsenic
0.0074
0.0065
Recirculation mode
Data from Table 2-3, based on 7
sampling events
Cadmium
0.00061
<0.00021
Gravity mode
Data from Table 2-2, based on 6
sampling events
Cadmium
0.00060
<0.00020
Recirculation mode
Data from Table 2-3, based on 7
sampling events
Chromium
0.0122
0.0078
Gravity mode
Data from Table 2-2, based on 6
sampling events
E-10
-------
Appendix E: Treatment Trains Data Tables
Table E-10: Average Influent and Effluent Concentrations - Leviathan Mine
Constituent
Average Influent
Average Effluent
Mode
Notes
Chromium
0.0111
0.0064
Recirculation mode
Data from Table 2-3, based on 7
sampling events
Copper
0.691
0.0048
Gravity mode
Data from Table 2-2, based on 6
sampling events
Copper
0.795
0.0046
Recirculation mode
Data from Table 2-3, based on 7
sampling events
Iron
117.167
4.885
Gravity mode
Data from Table 2-2, based on 6
sampling events
Iron
115.785
2.704
Recirculation mode
Data from Table 2-3, based on 7
sampling events
Lead
0.0036
0.0047
Gravity mode
Data from Table 2-2, based on 6
sampling events
Lead
0.0042
0.0025
Recirculation mode
Data from Table 2-3, based on 7
sampling events
Nickel
0.487
0.0655
Gravity mode
Data from Table 2-2, based on 6
sampling events
Nickel
0.529
0.0697
Recirculation mode
Data from Table 2-3, based on 7
sampling events
Selenium
0.0139
0.0112
Gravity mode
Data from Table 2-2, based on 6
sampling events
Selenium
0.0115
0.0085
Recirculation mode
Data from Table 2-3, based on 7
sampling events
Zinc
0.715
0.0158
Gravity mode
Data from Table 2-2, based on 6
sampling events
Zinc
0.776
0.0089
Recirculation mode
Data from Table 2-3, based on 7
sampling events
Notes:
Source: U.S. EPA, 2006a
All analytical results reported in mg/L
All constituent concentrations reported as dissolved.
E-ll
-------
Appendix E: Treatment Trains Data Tables
Table E-ll: Average Influent and Effluent Concentrations - Standard Mine
Constituent
Average
Influent
Average APC
Effluent
Notes
Cadmium
0.095
0.00063
Influent calculated from average BCR effluent and percent removal
provided in text; average APC effluent data provided in text.
Copper
0.10
0.0028
Influent calculated from average BCR effluent and percent removal
provided in text; average APC effluent data provided in text.
Iron
11.2
0.54
Influent calculated from average BCR effluent and percent removal
provided in text; average APC effluent data provided in text.
Lead
0.134
0.0038
Influent calculated from average BCR effluent and percent removal
provided in text; average APC effluent data provided in text.
Manganese
5.4-13.23
4.1
Manganese removal increased as APC matured and became fully
vegetated
Sulfate
281
122
Data from Table 4
Sulfide
<0.5
<0.5
Data from Table 4
Zinc
18.25
0.14
Influent calculated from average BCR effluent and percent removal
provided in text; average APC effluent data provided in text.
Notes:
Source: Gallagher et al., 2012
All analytical results reported in mg/L
All constituent concentrations reported as dissolved except for iron, which was reported as total.
a = Average not provided, represents range reported in text
APC = Aerobic Polishing Cell
NA = Not applicable
Table E-12: Average Influent and Effluent Concentrations - Tar Creek
Constituent
Average Influent
Average Effluent
Aluminum
0.094 ± 0.009
0.071 ± 0.030
Arsenic
0.063 ± 0.002
ND
Calcium
742 ± 9.0
740 ± 22.3
Cadmium
0.016 ± 0.002
ND
Chromium
0.001 ± 0.0002
0.002 ± 0.0006
Cobalt
0.066 ± 0.008
0.007 ± 0.0004
E-12
-------
Appendix E: Treatment Trains Data Tables
Table E-12: Average Influent and Effluent Concentrations - Tar Creek
Constituent
Average Influent
Average Effluent
Copper
0.002 ± 0.0003
0.003 ± 0.0003
Iron
177 ± 2.33
0.57 ±0.207
Lead
0.068 ± 0.003
ND
Lithium
0.366 ±0.010
0.365 ±0.018
Magnesium
200 ± 2.53
198 ± 7.49
Manganese
1.51 ±0.016
1.38 ±0.197
Nickel
0.945 ± 0.015
0.035 ± 0.007
Potassium
26.0 ±0.286
31.1 ±4.82
Sodium
94.9 ± 1.63
96.6 ±4.23
Sulfate
2,239 ± 26
2,047 ± 72
Zinc
8.29 ±0.078
0.096 ± 0.037
Notes:
Source: Nairn et al., 2011
All analytical results reported in mg/L
All constituent concentrations reported as total
Data from Table 3, representing flow-weighted influent and final system effluent as mean +/- standard
error
ND = Not detected
Table E-13: Average Influent and Effluent Concentrations - Wheal Jane Mine
Constituent
Average
Influent
Average
Effluent
Treatment
System
Notes
Aluminum
48.6
55.8
LD
Influent and effluent data reported in Table 3
Aluminum
48.6
3.3
ALD
Influent and effluent data reported in Table 2
Aluminum
48.6
75.8
LF
Influent and effluent data reported in Table 1
Arsenic
2.7
0.0
LD
Influent and effluent data reported in Table 3
Arsenic
2.7
0.0
ALD
Influent and effluent data reported in Table 2
Arsenic
2.7
0.0
LF
Influent and effluent data reported in Table 1
Cadmium
0.1
0.0
LD
Influent and effluent data reported in Table 3
Cadmium
0.1
0.0
ALD
Influent and effluent data reported in Table 2
Cadmium
0.1
0.0
LF
Influent and effluent data reported in Table 1
Copper
0.4
0.1
LD
Influent and effluent data reported in Table 3
E-13
-------
Appendix E: Treatment Trains Data Tables
Table E-13: Average Influent and Effluent Concentrations - Wheal Jane Mine
Constituent
Average
Average
Treatment
Notes
Influent
Effluent
System
Copper
0.4
0.0
ALD
Influent and effluent data reported
n Table 2
Copper
0.4
0.1
LF
Influent and effluent data reported
n Table 1
Iron
143.6
13.2
LD
Influent and effluent data reported
n Table 3
Iron
143.6
2.2
ALD
Influent and effluent data reported
n Table 2
Iron
143.6
12.7
LF
Influent and effluent data reported
n Table 1
Manganese
21.4
24.8
LD
Influent and effluent data reported
n Table 3
Manganese
21.4
12.2
ALD
Influent and effluent data reported
n Table 2
Manganese
21.4
27.6
LF
Influent and effluent data reported
n Table 1
Sulfate
1649.5
1591.2
LD
Influent and effluent data reported
n Table 3
Sulfate
1649.5
1150.4
ALD
Influent and effluent data reported
n Table 2
Sulfate
1649.5
1636.1
LF
Influent and effluent data reported
n Table 1
Zinc
82.0
45.6
LD
Influent and effluent data reported
n Table 3
Zinc
82.0
4.9
ALD
Influent and effluent data reported
n Table 2
Zinc
82.0
51.3
LF
Influent and effluent data reported
n Table 1
PH
3.8
3.0
LD
Influent and effluent data reported
n Table 3
PH
3.9
6.6
ALD
Influent and effluent data reported
n Table 2
PH
3.9
3.1
LF
Influent and effluent data reported
n Table 1
Source: Whitehead et al., 2005
The authors did not provide the time period over which the averages were calculated, but it may have
been over the same period for which the removal efficiencies were calculated (1999-2001) as reported in
Whitehead et al., 2005
The ALD became nonoperational in June 2000, after which the system operated as a second limestone-
dosed system
Whitehead et al., 2005 only reported one decimal place in Tables 1, 2 and 3
All analytical results reported in mg/L
All constituent concentrations reported as dissolved
pH results reported in standard units
LD = Limestone-dosed pre-treatment
ALD = Anoxic limestone drain
LF = Limestone-free system without pre-treatment
E-14
-------
Appendix E: Treatment Trains Data Tables
Table E-14: Removal Efficiencies - Calliope Mine
Constituent
Average Removal Efficiency
Maximum
Minimum
Notes
Aluminum
0.24%
99.90%
-430.81%
BCR II
Arsenic
18.93%
86.89%
-31.58%
BCR II
Cadmium
78.16%
95.97%
40.86%
BCR II
Copper
48.22%
99.76%
-233.33%
BCR II
Iron
-1446.83%
98.65%
-10192.68%
BCR II
Manganese
35.49%
98.46%
-185.71%
BCR II
Sulfate
4.62%
30.43%
-52.00%
BCR II
Zinc
77.62%
99.58%
25.48%
BCR II
Aluminum
43.61%
97.74%
-140.21%
BCR IV
Arsenic
-147.35%
62.90%
-839.29%
BCR IV
Cadmium
52.16%
84.85%
8.11%
BCR IV
Copper
79.66%
98.23%
-19.68%
BCR IV
Iron
-698.05%
20.42%
-2663.53%
BCR IV
Manganese
29.46%
98.81%
-6.72%
BCR IV
Sulfate
-12.78%
37.29%
-167.21%
BCR IV
Zinc
85.08%
96.84%
73.03%
BCR IV
Notes:
Source: Wilmoth, 2002
All analytical results reported in mg/L
pH results reported in standard units.
All constituent concentrations reported as total
EPA calculated removal efficiencies calculated for each sampling date from constituent data provided in Table 5-6 in Wilmoth, 2002. The average removal
efficiency for each metal was obtained from the individual calculated removal efficiencies for each sampling date.
Table E-15: Removal Efficiencies - Golden Sunli
*ht Mine
Constituent
Removal Efficiency
Notes
Aluminum
99.99%
Data originated from Table 4, collected March
12, 2003
Copper
99.99%
Data originated from Table 4, collected March
12, 2003
E-15
-------
Appendix E: Treatment Trains Data Tables
Table E-15: Removal Efficiencies - Golden Sunli
ght Mine
Constituent
Removal Efficiency
Notes
Iron
98.68%
Data originated from Table 4, collected March
12, 2003
Manganese
42.05%
Data originated from Table 4, collected March
12, 2003
Zinc
99.97%
Data originated from Table 4, collected March
12, 2003
Notes:
Source: Bless, 2008
EPA calculated average removal efficiencies from influent and effluent presented in Table E-8
All analytical results in mg/L
All constituent concentrations reported as dissolved
Table E-16: Removal Efficiencies - Leviathan Mine
Constituent
Water Sample
Removal Efficiency3
Mode
Notes
Aluminum
Dissolved
99.6%
Gravity mode
Data extracted from Table 2-13
Aluminum
Total
98.7%
Gravity mode
Data extracted from Table 2-17
Aluminum
Dissolved
99.7%
Recirculation mode
Data extracted from Table 2-15
Aluminum
Total
99.7%
Recirculation mode
Data extracted from Table 2-18
Arsenic
Dissolved
14.3%
Gravity mode
Data extracted from Table 2-13
Arsenic
Total
47.6%
Gravity mode
Data extracted from Table 2-17
Arsenic
Dissolved
-600%
Recirculation mode
Data extracted from Table 2-15
Arsenic
Total
-548%
Recirculation mode
Data extracted from Table 2-18
Cadmium
Dissolved
42.5%
Gravity mode
Data extracted from Table 2-13
Cadmium
Total
43.9%
Gravity mode
Data extracted from Table 2-17
Cadmium
Dissolved
83.0%
Recirculation mode
Data extracted from Table 2-15
Cadmium
Total
85.5%
Recirculation mode
Data extracted from Table 2-18
Chromium
Dissolved
62.8%
Gravity mode
Data extracted from Table 2-13
Chromium
Total
51.2%
Gravity mode
Data extracted from Table 2-17
Chromium
Dissolved
39.9%
Recirculation mode
Data extracted from Table 2-15
Chromium
Total
33.3%
Recirculation mode
Data extracted from Table 2-18
Copper
Dissolved
99.1%
Gravity mode
Data extracted from Table 2-13
Copper
Total
98.8%
Gravity mode
Data extracted from Table 2-17
Copper
Dissolved
98.8%
Recirculation mode
Data extracted from Table 2-15
E-16
-------
Appendix E: Treatment Trains Data Tables
Table E-16: Removal Efficiencies - Leviathan Mine
Constituent
Water Sample
Removal Efficiency3
Mode
Notes
Copper
Total
99%
Recirculation mode
Data extracted from Table 2-18
Iron
Dissolved
99.7%
Gravity mode
Data extracted from Table 2-13
Iron
Total
98.5%
Gravity mode
Data extracted from Table 2-17
Iron
Dissolved
99.7%
Recirculation mode
Data extracted from Table 2-15
Iron
Total
99.5%
Recirculation mode
Data extracted from Table 2-18
Lead
Dissolved
35.8%
Gravity mode
Data extracted from Table 2-13
Lead
Total
40.8%
Gravity mode
Data extracted from Table 2-17
Lead
Dissolved
47.5%
Recirculation mode
Data extracted from Table 2-15
Lead
Total
9.7%
Recirculation mode
Data extracted from Table 2-18
Nickel
Dissolved
89%
Gravity mode
Data extracted from Table 2-13
Nickel
Total
85%
Gravity mode
Data extracted from Table 2-17
Nickel
Dissolved
96.4%
Recirculation mode
Data extracted from Table 2-15
Nickel
Total
95.8%
Recirculation mode
Data extracted from Table 2-18
Selenium
Dissolved
9.4%
Gravity mode
Data extracted from Table 2-13
Selenium
Total
57.4%
Gravity mode
Data extracted from Table 2-17
Selenium
Dissolved
45.8%
Recirculation mode
Data extracted from Table 2-15
Selenium
Total
45.7%
Recirculation mode
Data extracted from Table 2-18
Sulfate
Total
23.18%b
Gravity mode
Data extracted from Table 2-9
Sulfate
Total
26.38%b
Recirculation mode
Data extracted from Table 2-11
Zinc
Dissolved
98.5%
Gravity mode
Data extracted from Table 2-13
Zinc
Total
97.9%
Gravity mode
Data extracted from Table 2-17
Zinc
Dissolved
99.4%
Recirculation mode
Data extracted from Table 2-15
Zinc
Total
98.6%
Recirculation mode
Data extracted from Table 2-18
Notes:
Source: U.S. EPA, 2006a
Leviathan gravity flow configuration data March 24, 2004; recirculation flow configuration data August 19, 2004.
a = Removal efficiency provided by source unless otherwise noted
b = EPA calculated removal efficiency based on influent and effluent concentrations presented in Table E-10
E-17
-------
Appendix E: Treatment Trains Data Tables
Table E-17: Minimum, Maximum and Average Removal Efficiencies - Leviathan Mine
Constituent
Minimum
Removal
Efficiency
Maximum
Removal
Efficiency
Average
Removal
Efficiency
Mode
Notes
Aluminum
99.5%
99.9%
99.7%
Gravity mode
Data from Table 2-2, based on
6 sampling events
Aluminum
99.7%
99.9%
99.9%
Recirculation mode
Data from Table 2-3, based on
7 sampling events
Arsenic
NC
NC
NC
Gravity mode
Data from Table 2-2, based on
6 sampling events
Arsenic
NC
NC
NC
Recirculation mode
Data from Table 2-3, based on
7 sampling events
Cadmium
42.5%
79%
65.3%
Gravity mode
Data from Table 2-2, based on
6 sampling events
Cadmium
NC
NC
NC
Recirculation mode
Data from Table 2-3, based on
7 sampling events
Chromium
NC
NC
NC
Gravity mode
Data from Table 2-2, based on
6 sampling events
Chromium
21.2%
84.8%
42.5%
Recirculation mode
Data from Table 2-3, based on
7 sampling events
Copper
99.1%
99.7%
99.3%
Gravity mode
Data from Table 2-2, based on
6 sampling events
Copper
98.8%
99.8%
99.4%
Recirculation mode
Data from Table 2-3, based on
7 sampling events
Iron
65.6%
99.9%
95.8%
Gravity mode
Data from Table 2-2, based on
6 sampling events
Iron
92.8%
99.7%
97.7%
Recirculation mode
Data from Table 2-3, based on
7 sampling events
Lead
NC
NC
NC
Gravity mode
Data from Table 2-2, based on
6 sampling events
Lead
22.0%
57.1%
41.3%
Recirculation mode
Data from Table 2-3, based on
7 sampling events
Nickel
72.1%
92.6%
86.6%
Gravity mode
Data from Table 2-2, based on
6 sampling events
Nickel
71.0%
96.4%
86.8%
Recirculation mode
Data from Table 2-3, based on
7 sampling events
E-18
-------
Appendix E: Treatment Trains Data Tables
Table E-17: Minimum, Maximum and Average Removal Efficiencies - Leviathan Mine
Constituent
Minimum
Removal
Efficiency
Maximum
Removal
Efficiency
Average
Removal
Efficiency
Mode
Notes
Selenium
NC
NC
NC
Gravity mode
Data from Table 2-2, based on
6 sampling events
Selenium
NC
NC
NC
Recirculation mode
Data from Table 2-3, based on
7 sampling events
Zinc
95.9%
98.6%
97.8%
Gravity mode
Data from Table 2-2, based on
6 sampling events
Zinc
97.7%
99.8%
98.9%
Recirculation mode
Data from Table 2-3, based on
7 sampling events
Notes:
Source: U.S. EPA, 2006a
NC = Not calculated because influent and effluent concentrations are not statistically different
All constituents reported as dissolved
Table E-18: Average Removal Efficiencies - Standard Mine
Constituent
Average Removal
Efficiency
Notes
Cadmium
99.34%
Removal efficiency calculated from average influent and average
APC effluent.
Copper
97.2%
Removal efficiency calculated from average influent and average
APC effluent.
Iron
95.18%
Removal efficiency calculated from average influent and average
APC effluent.
Lead
97.16%
Removal efficiency calculated from average influent and average
APC effluent.
Manganese
42.2% (2009)
87.7% (2010)
Removal efficiencies provided in text.
Sulfate
56.58%
Data from Table 4
Zinc
99.23%
Removal efficiency calculated from average influent and average
APC effluent.
E-19
-------
Appendix E: Treatment Trains Data Tables
Table E-18: Average Removal Efficiencies - Standard Mine
Constituent
Average Removal
Notes
Efficiency
Notes:
Source: Gallagher et al., 2012
APC = Aerobic Polishing Cell
All constituent concentrations reported as dissolved except for iron, which was reported as total
Table E-19: Removal Efficiencies - Surething Mine
Constituent
Removal Efficiency
Aluminum
>99.86%
Arsenic
>92.13%
Cadmium
>99.96%
Copper
>99.87%
Iron
>99.91%
Lead
97.35%
Manganese
99.86%
Zinc
>99.97%
Notes:
Source: Nordwick and Bless, 2008
EPA calculated removal efficiencies based on data presented in Table 4-2 in
Nordwick and Bless, 2008 and reported in Table E-20.
Table E-20: Average Removal Efficiencies-Tar Creek
Constituent
Average Removal Efficiency
Iron
99.7%
Nickel
98.8%
Zinc
96.3%
Notes:
E-20
-------
Appendix E: Treatment Trains Data Tables
Table E-20: Average Removal Efficiencies-Tar Creek
Constituent
Average Removal Efficiency
Notes:
Source: Nairn et al., 2010b
Removal efficiencies reported in text of Nairn et al., 2010b
Table E-21: Removal Efficiencies - Wheal Jane Mine
Constituent
Removal Efficiency
Treatment System
Iron
98%
LD
Iron
>99%
ALD
Iron
>98%
LF
Zinc
65%
LD
Zinc
58%
ALD
Zinc
98%
LF
Sulfate
-40%
LD
Sulfate
-66%
ALD
Sulfate
23%
LF
Notes:
Source: Johnson and Hallberg, 2005, based sampling conducted on
September 19, 2002
The ALD became nonoperational in June 2000, after which the system
operated as a second limestone-dosed system
EPA calculated removal efficiency from influent and effluent concentrations in
Johnson and Hallberg, 2005
Total or dissolved not specified
LD = Limestone-dosed pre-treatment
ALD = Anoxic limestone drain
LF = Limestone-free system without pre-treatment
ORP = Oxidation-reduction potential
E-21
-------
Appendix E:
Treatment Trains Data Tables
Table E-22: Med
ian Removal Efficiencies - Wheal Jane Mine
Constituent
Median Removal
Efficiency
Treatment System
Aluminum
65%
LD
Aluminum
90%
ALD
Aluminum
35%
LF
Cadmium
78%
LD
Cadmium
98%
ALD
Cadmium
53%
LF
Copper
73%
LD
Copper
95%
ALD
Copper
42%
LF
Manganese
54%
LD
Manganese
60%
ALD
Manganese
45%
LF
Zinc
66%
LD
Zinc
73%
ALD
Zinc
47%
LF
Notes:
Source: Whitehead et al., 2005, Table 4
The authors indicated that median removal efficiencies were based
on data collected from 1999-2001.
The ALD became nonoperational in June 2000, after which the
system operated as a second limestone-dosed system.
Median removal efficiencies were not provided for arsenic or iron
All constituent concentrations reported as dissolved
LD = Limestone-dosed pre-treatment
ALD = Anoxic limestone drain
LF = Limestone-free system without pre-treatment
E-22
-------
Appendix E: Treatment Trains Data Tables
Table E-23: Pre- and Post-Reclamation Concentrations-Valzinco Mine
Constituent
Pre-Reclamation Concentration
Post-Reclamation
Concentration
Range
Mean
Aluminum
0.6-19.5
3.1
0.051
Cadmium
0.0032 -0.088
0.0152
0.00091
Copper
0.049-2.2
0.3116
0.0097
Iron
5.0-69.7
17.7
1.01
Lead
0.170-1.3
0.349
0.0016
Manganese
0.410-2.1
0.779
1.12
Nickel
0.002-0.037
0.0085
0.0023
Sulfate
27.0 -1,400
204
38.0
Zinc
1.9-27.0
5.75
1.32
Hardness
10.0-62.0
21.2
29.0
PH
2.6-4.0
3.4
5.1
Notes:
Source: Seal et al., 2008
All analytical results in mg/L
All constituent concentrations reported as dissolved
pH results reported in standard units
Hardness reported as mg/L CaCC>3
Data from Table 1. Pre-reclamation and post-reclamation collected at same sample location: pre-reclamation data collected
1998-2001; post-reclamation data collected June 2007
Table E-24: Influent and Effluent Concentrations - Copper Basin Mining District
Constituent
Maximum Influent
Maximum Effluent
Notes
Aluminum
1.423
0.055
Data from Table 1 in source, represent the maximum influent and the
maximum effluent observed between 2004 and 2006
Copper
0.197
0.017
Data from Table 1 in source, represent the maximum influent and the
maximum effluent observed between 2004 and 2006
E-23
-------
Appendix E: Treatment Trains Data Tables
Table E-24: Influent and Effluent Concentrations - Copper Basin Mining District
Constituent
Maximum Influent
Maximum Effluent
Notes
Iron
0.211
0.133
Data from Table 1 in source, represent the maximum influent and the
maximum effluent observed between 2004 and 2006
Manganese
1.148
0.294
Data from Table 1 in source, represent the maximum influent and the
maximum effluent observed between 2004 and 2006
Sulfate
110
104
Data from Table 1 in source, represent the maximum influent and the
maximum effluent observed between 2004 and 2006
Zinc
0.640
0.197
Data from Table 1 in source, represent the maximum influent and the
maximum effluent observed between 2004 and 2006
Acidity
37
<1
Data from Table 1 in source, represent the maximum influent and the
maximum effluent observed between 2004 and 2006
Alkalinity
<1
45
Data from Table 1 in source, represent the maximum influent and the
maximum effluent observed between 2004 and 2006
Hardness
97
142
Data from Table 1 in source, represent the maximum influent and the
maximum effluent observed between 2004 and 2006
PH
4.28
7.16
Data from Table 1 in source, represent the maximum influent and the
maximum effluent observed between 2004 and 2006
Notes:
Source: U.S. EPA, 2006b
All analytical results in mg/L
All constituent concentrations reported as total except for manganese, which was reported as dissolved
pH results reported in standard units
NA = not applicable
Table E-25 Average Influent and Effluent Concentrations - Dunka Mine
Constituent3
Average
Influent
Average
Effluent
Timeframe
Notes
Cobalt
0.015
0.006
Jan. to Sept. 1998
EM8 aerobic wetland with limestone beds incorporated into the wetland - ITRC,
2010
Copper
0.026
0.009
1999 to 2004
EM8 aerobic wetland with limestone beds incorporated into the wetland - Eger
and Eger, 2005
E-24
-------
Appendix E: Treatment Trains Data Tables
Table E-25 Average Influent and Effluent Concentrations - Dunka Mine
Constituent3
Average
Influent
Average
Effluent
Timeframe
Notes
Copper
0.029
0.011
Jan. to Sept. 1998
EM8 aerobic wetland with limestone beds incorporated into the wetland - ITRC,
2010
Nickel
2.08
1.4
1999 to 2004
EM8 aerobic wetland with limestone beds incorporated into the wetland - Eger
and Eger, 2005
Nickel
1.600
0.902
Jan. to Sept. 1998
EM8 aerobic wetland with limestone beds incorporated into the wetland - ITRC,
2010
Zinc
0.052
0.032
1999 to 2004
EM8 aerobic wetland with limestone beds incorporated into the wetland - Eger
and Eger, 2005
Zinc
0.059
0.033
Jan. to Sept. 1998
EM8 aerobic wetland with limestone beds incorporated into the wetland - ITRC,
2010
PH
7.41
7.3
1999 to 2004
EM8 aerobic wetland with limestone beds incorporated into the wetland - Eger
and Eger, 2005
PH
7.20
7.01
Jan. to Sept. 1998
EM8 aerobic wetland with limestone beds incorporated into the wetland - ITRC,
2010
Cobalt
0.13
0.04
1995 to 1997
Seep 1 aerobic wetland with post-treatment limestone bed - Eger and Eger, 2005
Copper
0.15
0.05
1995 to 1997
Seep 1 aerobic wetland with post-treatment limestone bed - Eger and Eger, 2005
Copper
0.325
0.043
1999 to 2004
Seep 1 aerobic wetland with post-treatment limestone bed - Eger and Eger, 2005
Nickel
5.39
1.85
1995 to 1997
Seep 1 aerobic wetland with post-treatment limestone bed - Eger and Eger, 2005
Nickel
6.64
3.27
1999 to 2004
Seep 1 aerobic wetland with post-treatment limestone bed - Eger and Eger, 2005
Zinc
0.65
0.29
1995 to 1997
Seep 1 aerobic wetland with post-treatment limestone bed - Eger and Eger, 2005
Zinc
0.928
0.385
1999 to 2004
Seep 1 aerobic wetland with post-treatment limestone bed - Eger and Eger, 2005
PH
6.94
7.23
1995 to 1997
Seep 1 aerobic wetland with post-treatment limestone bed- Eger and Eger, 2005
E-25
-------
Appendix E: Treatment Trains Data Tables
Table E-25 Average Influent and Effluent Concentrations - Dunka Mine
Constituent3
Average
Influent
Average
Effluent
Timeframe
Notes
PH
7.28
7.34
1999 to 2004
Seep 1 aerobic wetland with post-treatment limestone bed - Eger and Eger, 2005
Cobalt
0.08
0.02
1995 to 1997
Seep X aerobic wetland with pre- and post-treatment limestone beds - Eger and
Eger, 2005
Copper
0.33
0.08
1995 to 1997
Seep X aerobic wetland with pre- and post-treatment limestone beds - Eger and
Eger, 2005
Copper
0.37
0.11
1999 to 2004
Seep X aerobic wetland with pre- and post-treatment limestone beds - Eger and
Eger, 2005
Nickel
1.5
0.61
1995 to 1997
Seep X aerobic wetland with pre- and post-treatment limestone beds - Eger and
Eger, 2005
Nickel
1.82
1.09
1999 to 2004
Seep X aerobic wetland with pre- and post-treatment limestone beds - Eger and
Eger, 2005
Zinc
0.48
0.21
1995 to 1997
Seep X aerobic wetland with pre- and post-treatment limestone beds - Eger and
Eger, 2005
Zinc
0.58
0.37
1999 to 2004
Seep X aerobic wetland with pre- and post-treatment limestone beds - Eger and
Eger, 2005
PH
7.03
7.13
1995 to 1997
Seep X aerobic wetland with pre- and post-treatment limestone beds - Eger and
Eger, 2005
PH
7.38
7.35
1999 to 2004
Seep X aerobic wetland with pre- and post-treatment limestone beds - Eger and
Eger, 2005
Cobalt
0.02
0.002
1992 to 1994
W2D/3D aerobic wetland with post-treatment limestone beds - Eger and Eger,
2005
Cobalt
0.02
0.002
1992 to 1997
W2D/3D aerobic wetland with post-treatment limestone beds - ITRC, 2010
Cobalt
0.02
NR
1996 to 1998
W2D/3D aerobic wetland with post-treatment limestone beds - Eger and Eger,
2005
Cobaltb
0.02
NR
1999 to 2004
W2D/3D aerobic wetland with post-treatment limestone beds - Eger and Eger,
2005
Copper
0.05
0.004
1992 to 1994
W2D/3D aerobic wetland with post-treatment limestone beds - Eger and Eger,
2005
E-26
-------
Appendix E: Treatment Trains Data Tables
Table E-25 Average Influent and Effluent Concentrations - Dunka Mine
Constituent3
Average
Influent
Average
Effluent
Timeframe
Notes
Copper
0.05
0.004
1992 to 1997
W2D/3D aerobic wetland with post-treatment limestone beds - ITRC, 2010
Copper
0.05
<0.001
1996 to 1998
W2D/3D aerobic wetland with post-treatment limestone beds - Eger and Eger,
2005
Copperb
0.05
0.002
1999 to 2004
W2D/3D aerobic wetland with post-treatment limestone beds - Eger and Eger,
2005
Nickel
1.90
0.08
1992 to 1994
W2D/3D aerobic wetland with post-treatment limestone beds - Eger and Eger,
2005
Nickel
1.90
0.080
1992 to 1997
W2D/3D aerobic wetland with post-treatment limestone beds - ITRC, 2010
Nickel
1.90
0.06
1996 to 1998
W2D/3D aerobic wetland with post-treatment limestone beds - Eger and Eger,
2005
Nickelb
1.90
0.036
1999 to 2004
W2D/3D aerobic wetland with post-treatment limestone beds - Eger and Eger,
2005
Zinc
0.05
0.008
1992 to 1994
W2D/3D aerobic wetland with post-treatment limestone beds - Eger and Eger,
2005
Zinc
0.05
0.008
1992 to 1997
W2D/3D aerobic wetland with post-treatment limestone beds - ITRC, 2010
Zinc
0.05
<0.001
1996 to 1998
W2D/3D aerobic wetland with post-treatment limestone beds - Eger and Eger,
2005
Zincb
0.05
0.006
1999 to 2004
W2D/3D aerobic wetland with post-treatment limestone beds - Eger and Eger,
2005
PH
7.0
7.0
1992 to 1994
W2D/3D aerobic wetland with post-treatment limestone beds - Eger and Eger,
2005
PH
7.0
7.0
1992 to 1997
W2D/3D aerobic wetland with post-treatment limestone beds - ITRC, 2010
PH
7.0
7.0
1996 to 1998
W2D/3D aerobic wetland with post-treatment limestone beds - Eger and Eger,
2005
pHb
7.0
7.4
1999 to 2004
W2D/3D aerobic wetland with post-treatment limestone beds - Eger and Eger,
2005
E-27
-------
Appendix E: Treatment Trains Data Tables
Table E-25 Average Influent and Effluent Concentrations - Dunka Mine
Constituent3
Average
Influent
Average
Effluent
Timeframe
Notes
Notes:
Sources: Eger and Eger, 2005 and ITRC, 2010
All analytical results reported in mg/L
pH reported in standard units
a = total or dissolved not specified
b = reported values noted as being estimates
NR = not reported
Table E-26: Average Removal Efficiencies - Dunka Mine
Constituent3
Timeframe
Average Removal
Efficiency
Notes
Cobalt
Jan. to Sept. 1998
60%
EM8 aerobic wetland with limestone beds incorporated into the
wetland - ITRC, 2010
Copper
1999 to 2004
65%
EM8 aerobic wetland with limestone beds incorporated into the
wetland - Eger and Eger, 2005
Copper
Jan. to Sept. 1998
62%
EM8 aerobic wetland with limestone beds incorporated into the
wetland - ITRC, 2010
Nickel
1999 to 2004
33%
EM8 aerobic wetland with limestone beds incorporated into the
wetland - Eger and Eger, 2005
Nickelb
Jan. to Sept. 1998
44%
EM8 aerobic wetland with limestone beds incorporated into the
wetland - ITRC, 2010
Zinc
1999 to 2004
38%
EM8 aerobic wetland with limestone beds incorporated into the
wetland - Eger and Eger, 2005
Zinc
Jan. to Sept. 1998
44%
EM8 aerobic wetland with limestone beds incorporated into the
wetland - ITRC, 2010
Cobalt
1995 to 1997
69%
Seep 1 aerobic wetland with post-treatment limestone bed - Eger
and Eger, 2005
E-28
-------
Appendix E: Treatment Trains Data Tables
Table E-26: Average Removal Efficiencies - Dunka Mine
Constituent3
Timeframe
Average Removal
Efficiency
Notes
Copper
1995 to 1997
67%
Seep 1 aerobic wetland with post-treatment limestone bed - Eger
and Eger, 2005
Copper
1999 to 2004
87%
Seep 1 aerobic wetland with post-treatment limestone bed - Eger
and Eger, 2005
Nickel
1995 to 1997
66%
Seep 1 aerobic wetland with post-treatment limestone bed - Eger
and Eger, 2005
Nickel
1999 to 2004
51%
Seep 1 aerobic wetland with post-treatment limestone bed - Eger
and Eger, 2005
Zinc
1995 to 1997
55%
Seep 1 aerobic wetland with post-treatment limestone bed - Eger
and Eger, 2005
Zinc
1999 to 2004
59%
Seep 1 aerobic wetland with post-treatment limestone bed - Eger
and Eger, 2005
Cobalt
1995 to 1997
75%
Seep X aerobic wetland with pre- and post-treatment limestone
beds - Eger and Eger, 2005
Copper
1995 to 1997
76%
Seep X aerobic wetland with pre- and post-treatment limestone
beds - Eger and Eger, 2005
Copper
1999 to 2004
70%
Seep X aerobic wetland with pre- and post-treatment limestone
beds - Eger and Eger, 2005
Nickel
1995 to 1997
59%
Seep X aerobic wetland with pre- and post-treatment limestone
beds - Eger and Eger, 2005
Nickel
1999 to 2004
40%
Seep X aerobic wetland with pre- and post-treatment limestone
beds - Eger and Eger, 2005
Zinc
1995 to 1997
56%
Seep X aerobic wetland with pre- and post-treatment limestone
beds - Eger and Eger, 2005
Zinc
1999 to 2004
36%
Seep X aerobic wetland with pre- and post-treatment limestone
beds - Eger and Eger, 2005
Cobalt
1992 to 1994
90%
W2D/3D aerobic wetland with post-treatment limestone beds -
Eger and Eger, 2005
Cobalt
1992 to 1997
90%
W2D/3D aerobic wetland with post-treatment limestone beds -
ITRC, 2010
E-29
-------
Appendix E: Treatment Trains Data Tables
Table E-26: Average Removal Efficiencies - Dunka Mine
Constituent3
Timeframe
Average Removal
Efficiency
Notes
Copper
1992 to 1994
92%
W2D/3D aerobic wetland with post-treatment limestone beds -
Eger and Eger, 2005
Copper
1992 to 1997
92%
W2D/3D aerobic wetland with post-treatment limestone beds -
ITRC, 2010
Copper
1996 to 1998
99%c
W2D/3D aerobic wetland with post-treatment limestone beds -
Eger and Eger, 2005
Copper
1999 to 2004
96%
W2D/3D aerobic wetland with post-treatment limestone beds -
Eger and Eger, 2005
Nickel
1992 to 1994
96%
W2D/3D aerobic wetland with post-treatment limestone beds -
Eger and Eger, 2005
Nickel
1992 to 1997
96%
W2D/3D aerobic wetland with post-treatment limestone beds -
ITRC, 2010
Nickel
1996 to 1998
97%
W2D/3D aerobic wetland with post-treatment limestone beds -
Eger and Eger, 2005
Nickelb
1999 to 2004
98%
W2D/3D aerobic wetland with post-treatment limestone beds -
Eger and Eger, 2005
Zinc
1992 to 1994
84%
W2D/3D aerobic wetland with post-treatment limestone beds -
Eger and Eger, 2005
Zinc
1992 to 1997
84%
W2D/3D aerobic wetland with post-treatment limestone beds -
ITRC, 2010
Zinc
1996 to 1998
99%
W2D/3D aerobic wetland with post-treatment limestone beds -
Eger and Eger, 2005
Zinc
1999 to 2004
88%
W2D/3D aerobic wetland with post-treatment limestone beds -
Eger and Eger, 2005
Notes:
Sources: Eger and Eger, 2005 and ITRC, 2010
EPA calculated average removal efficiencies from average influent and effluent values presented in Table E-5 for each timeframe
a = Total or dissolved not specified, unless noted otherwise
b = Total
d = Vz the average detection limit used to calculate average removal efficiency
E-30
-------
Appendix E: Treatment Trains Data Tables
Table E-27: Flow Rates - All Treatment Train Mine Sites
Site
Flow Rate (lymin)
Source
Notes
Calliope
3.8 with four months at 7.6
Wilmoth, 2002
Operational flow rate
Copper Basin
1,102
U.S. EPA, 2006b
Average flow rate
310
ITRC, 2010
Average flow rate;
Jan. to Sept. 1998;
EM8 aerobic wetland with
limestone beds incorporated
into the wetland
400
Eger and Eger, 2005
Average flow rate;
1995 to 1997;
EM8 aerobic wetland with
limestone beds incorporated
into the wetland
Dunka
20
Eger and Eger, 2005
Average flow rate;
1995 to 1997;
Seep 1 aerobic wetland with
post-treatment limestone bed
27
Eger and Eger, 2005
Average flow rate;
1999 to 2004;
Seep 1 aerobic wetland with
post-treatment limestone bed
100
Eger and Eger, 2005
Average flow rate;
1995 to 1997;
Seep X aerobic wetland with
pre- and post-treatment
limestone beds
103
Eger and Eger, 2005
Average flow rate;
1999 to 2004;
Seep X aerobic wetland with
pre- and post-treatment
limestone beds
E-31
-------
Appendix E: Treatment Trains Data Tables
Table E-27: Flow Rates - All Treatment Train Mine Sites
Site
Flow Rate (lymin)
Source
Notes
75
Eger and Eger, 2005
Average flow rate;
1992 to 1994;
W2D/3D aerobic wetland with
post-treatment limestone
beds
75
Eger and Eger, 2005
Average flow rate;
1992 to 1997;
W2D/3D aerobic wetland with
post-treatment limestone
beds
45
Eger and Eger, 2005
Average flow rate;
1996 to 1998;
W2D/3D aerobic wetland with
post-treatment limestone
beds
45
Eger and Eger, 2005
Average flow rate;
1999 to 2004;
W2D/3D aerobic wetland with
post-treatment limestone
beds
510-1,464
Jarvis et al., 2015
Influent flow rate range;
2011-2014
Force Crag
888
Jarvis et al., 2015
Average flow rate;
2011-2014
360
Jarvis et al., 2015
Design flow rate
Golden
Sunlight
11.4
Bless et al., 2008
Design flow rate; BCR
operated at 7.6 L/min
Leviathan
31.8 (gravity-flow mode)
34.2 (recirculation mode)
Doshi, 2006
Reported for 2003-2005
Monte
1
Macias et al., 2012a
Operational flow rate in NFOL
Romero
90
Macias et al., 2012a
Influent flow rate
Standard
3.8
Gallagher et al.,
2012
Design flow rate
E-32
-------
Appendix E: Treatment Trains Data Tables
Table E-27: Flow Rates - All Treatment Train Mine Sites
Site
Flow Rate (lymin)
Source
Notes
Surething
7.6
Doshi, 2006
Design flow rate; actual
discharge reached peaks of 38
L/min
Tar Creek
1,000
Nairn et al., 2010a
Design flow rate
Valzinco
342 - 4,200
Seal et al., 2008
Flow rate range at sample
location VLZN-3
Wheal Jane
12-24
Whitehead et al.,
2005
Operational flow rate range
Notes:
Wilmoth, 2002 reported flow data associated with influent and effluent samples results at Calliope Mine;
these flows are shown in Table E-l
Table E-28: Average Influent and Effluent Concentrations - Monte Romero Mine
Constituent
Average Influent
Average Effluent
Aluminum
100
<0.2
Arsenic
0.507
<0.002
Calcium
250
850
Copper
5
<0.005
Iron
275
<0.2
Lead
0.174
<0.001
Magnesium
255
386
Manganese
18
19
Potassium
5
7
Silicon
37
11
Sulfate
3,430
3,770
Zinc
440
414
Eh
508
341
PH
3
6.6
E-33
-------
Appendix E: Treatment Trains Data Tables
Table E-28: Average Influent and Effluent Concentrations - Monte Romero Mine
Constituent
Average Influent
Average Effluent
Notes:
Source: Macias et al., 2012a
All analytical results in mg/L
All constituent concentrations reported as total
pH results reported in standard units.
Influent represents untreated water in the "Shaft" samples
Effluent is the overall system effluent, represented by "T2 Out" samples
Influent and effluent averages from Table 1 and represent monitoring from April to September
2008
Table E-29: Average Removal Efficiencies - Monte Romero Mine
Constituent
Average Removal Efficiency
Aluminum
99.90%
Arsenic
100.00%
Calcium
-240.00%
Copper
99.95%
Iron
99.96%
Lead
100.00%
Magnesium
-51.37%
Manganese
-5.56%
Potassium
-40.00%
Silicon
70.27%
Sulfate
-9.91%
Zinc
5.91%
Notes:
Source: Macias et al., 2012a
EPA calculated average removal efficiencies based on influent and effluent
concentration averages provided in Table E-14
E-34
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