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

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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

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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,

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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.

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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.

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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).

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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.







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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

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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).

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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


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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


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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

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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.

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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.

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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.

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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/.

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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


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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


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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


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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


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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


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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

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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,

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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


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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.

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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


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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


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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


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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


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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


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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


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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


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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


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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.

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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


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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


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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


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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


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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


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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


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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


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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


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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


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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


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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


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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


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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


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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


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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


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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


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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


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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.

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Constructed Wetlands

https://vtechworks.lib.vt.edu/bitstream/handle/10919/56136/460-133.pdf?sequence=l. Last accessed
10/22/18.

7-11


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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


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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


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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


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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


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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


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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


-------
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


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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


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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


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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


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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


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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


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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


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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


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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


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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


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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


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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


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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


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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


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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


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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


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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


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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


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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


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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


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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


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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.

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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.

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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


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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


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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


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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


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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


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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


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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


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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


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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


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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


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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


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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


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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


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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


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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


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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


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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


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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


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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


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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


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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


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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


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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


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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


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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


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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


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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


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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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