SME 2016 Annual Conference & Expo

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Dan Eyde

CTO & President

St. Cloud Mining Company

Barbara Carroll – GeoGRAFX GIS Services

A Review of Zeolite Based Treatment

Water Systems and Their Applicability

in Hard Rock, Coal and Uranium Mining

Applications

Agenda

1. What are zeolites?

2. Selected large scale zeolite treatment projects

3. Case 1: West Virginia Coal Case study

4. Case 2: Homestake Uranium Tailings leak Grants, NM

5. Case 3: CR Kendall thallium control Hilger, MT

6. Case 4: Lead Queen Mine Passive treatment system Patagonia, AZ

7. Questions?

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What are Zeolites?

Zeolites are used commercially for several

reasons:

* Unique absorption

* Ion exchange

* Molecular sieve

* Catalytic abilities

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Natural zeolites are hydrated aluminosilicates.

Natural Zeolite-based Media Systems

• Natural zeolites are readily available. The resources are

large, well tested and consistent in performance.

• There are a number of available technologies that

improve sorbent selectivity or increase capacity for

specific contaminants.

• Technology is proven in municipal and drinking water,

nuclear, and industrial water treatment applications and

is becoming more common in polishing mine effluents

prior to discharge.

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Selected Large Scale Zeolite Projects

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Project Contaminant

Three Mile Island Cesium, Strontium

Kendall Gold Mine – Hilger, MT Thallium, Cu, Pb, Zn, Co

Homestake Legacy Site - Grants, NM Uranium

Colorado Tailings, Butte, MT Cu, Pb, Zn, Ag - Pilot

Greenbriar Coal – West Virgina AMD, Mn, Al - Pilot

Rimcon – Wyoming Mitigation High Sodic waters

WRT – >100 Commercial installations Arsenic, Radium, Thorium, Uranium

Fukushima, Japan – Kurion Cesium, Strontium, Americium,

Calcium

Case 1 - West Virginia – Coal Mine Water

Discharge

Issues to be resolved included the following:

• AMD – pH of the water can be extremely low

• Manganese

• Aluminum

• Iron

• Turbidity

• TDS

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Location Map

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Brown Creek

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Buck Lilly

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Midland 2 & Point Mountain

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WV Test 1- Does Zeolite Do Anything?

Parameter Sample 1 Sample 2 Sample 3

pH 3.31 2.97 2.52

Dissolved Fe 2.48 9.23 617.20

Dissolved Mn 32.23 53.13 29.34

Dissolved Al 48.82 52.24 109.80

RAW WATER ANALYSIS

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Test 1 Results Parameter Raw Water After Zeolite

pH 3.31 5.71

Dissolved Fe 2.48 0.21

Dissolved Mn 32.23 8.27

Dissolved Al 48.82 0.11

Sample 1

Parameter Raw Water After Zeolite

pH 2.97 5.32

Dissolved Fe 9.23 0.22

Dissolved Mn 53.13 14.83

Dissolved Al 52.24 0.46

Sample 2

Parameter Raw Water After Zeolite

pH 2.52 4.00

Dissolved Fe 617.20 46.60

Dissolved Mn 29.34 30.01

Dissolved Al 109.80 12.05

Sample 3

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Test 2-Al Extraction

Parameter Raw AMD AMD-NaOH AMD-NaOH

Zeolite

AMD-Ca(OH)2 AMD-Ca(OH)2

Zeolite

pH 3.45 10.89 8.29 11.71 9.64

Alkalinity <0.45 162.64 25.23 604.67 31.51

Acidity 739.89 <0.33 <0.33 <0.33 <0.33

Conductivity 4,410.00 4,310.00 2,548.00 4,820.00 2,677.00

Dissolved Fe 213.00 0.01 0.04 0.02 0.01

Dissolved

Mn

30.50 <0.001 0.02 0.001 <0.001

Dissolved Al 52.68 1.46 <0.008 0.127 <0.008

Dissolved Na 25.78 871.30 336.20 54.44 156.80

Dissolved

Mg

149.30 0.34 35.37 0.24 16.01

Dissolved Ca 194.86 84.61 221.60 936.30 518.40

TDS 3,111.00 2,914.00 2,025.00 3,320.00 2,120.00

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Zeolite Practical Application

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Zeolite Practical Application

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Navigator Selenium Pilot

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Case 2 - Legacy Uranium Mining and

Processing Grants, NM

• Uranium Processing facility built 1958 on remote ranchland

• Operated by Homestake or related entities through 1990

• Presently inactive except for ongoing remediating implemented in 1977

• June 2007 NM lowered standard for uranium in groundwater from 5000 ppb to 30 ppb matching the EPA MCL since 2000

• Use RO to augment the groundwater cleanup activities. Brine from RO put in evaporation ponds

• Testing zeolite to treat low concentrations of Ur contaminated water from Upper Chinle formation. Supernatent re-injected at rate of 50-100 gpm. System design RIMCON, LLC.

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Location Map

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Uranium Concentration of the

Alluvial Aquifer

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Geologic Cross Section

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Zeolite pilot-test area on the south side of the top of the large tailing pile.

Note extraction wells (white) and piping in foreground used to convey

collected groundwater to the RO treatment plant or to one of the evaporation

ponds for disposal. View looking northeast. 2/20/2016 21

Zeolite Pilot-Test Area

Zeolite pilot-test pit on the top of the large tailing pile. The zeolite is used to

extract low-concentration uranium before being re-injected at 50 gallons per

minute. Pit is lined with a 60 millimeter thick high density polyethylene

(HPDE) liner. View looking northeast. 2/20/2016 22

Zeolite Pilot-Test Pit

Update

• Pilot scale system worked as designed.

• Homestake committed to installing large scale system.

• Permitting and regulatory approvals received.

• Full scale installation late 2014-15.

For further information on system contact:

RIMCON, LLC

Dale Shay – Principal

rimcon@midconetwork.com

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Case 3 - Thallium Removal Setup at

CR Kendall Hilger Mine Montana

Kendall Mine , MT Thallium

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Final Mine Closure and Water

Management Plan 2012

• Kendall Mine area in intermittent operation since 1880.Present operations started in 1981 and continued through 1995 with gold recovery through 1997.

• All components of the Closure Water Management plan – Watershed flow augmentation, Groundwater capture, zeolite water treatment, discharge of treated water into the Kendall Pit in place sine 1998

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Kendall Mine – Zeolite Treatment System

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Mini Zeolite Column Profile

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Mini-columns For Pilot Testing

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Pilot Test #2 Results – Normal Scale

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Pilot Test #2 Results – Log Scale

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TCLP - Leaching Results

Metal Concentration (mg/L)

TCLP SPLP

Arsenic < 0.5 < 0.5

Barium < 10 < 1

Cadmium < 0.1 < 0.1

Chromium < 0.5 < 0.5

Lead < 0.5 < 0.5

Mercury < 0.02 < 0.02

Selenium < 0.1 < 0.1

Silver < 0.5 < 0.5

Thallium 1.89 0.08

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Case 4 Southern AZ AMD and Metals

Watershed area mitigation of AMD and

selected heavy metals:

• Raise pH of drainage waters

• Reduce zinc, cadmium, lead, and

copper in Alum Gulch-Flux Canyon and

Cox Gulch-3R Canyon, SE Arizona

utilizing gabion retaining wall and footer

structures combined with zeolite

material adsorption 2/20/2016 33

Location

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Legacy mining activity at the

top of the watershed

produces acid mine

drainage which is

incorporated in groundwater

& surface water discharges

(tailings, tunneling, wall

rock)

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Reasons for this Project

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Several large removal

actions and expensive mine

portal closures implemented

in the area have had little

effect on heavy metals and

AMD -impacted loading

characteristics of several

tributaries flowing into

Sonoita Creek and

Patagonia Lake.

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Reasons for this Project

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Project Location

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Affected Lead Queen Mine Drainage

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Geologic Map

Geologic Influences on

Water and Soil and Overall

Watershed Ecology

Average chemical composition of mine tailings in the Harshaw Creek Watershed

(measured in ppm). From Dean (1982, p.46)

TRENCH MINE TAILINGS

pH 2.6

SO4 41,076

Fe 6,050

Cu 43

Mn 4,621

Zn 838

As 466

Pb 3,972

Cd 20

Cr 16

Se 0

Hg 5.4

Ag 25

Al 528, 725

Storm-related Surface water from Trench Mine

Tailings (mg/L)

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Storm-related Surface Water from

Trench Mine Tailings

GEOLOGIC STRUCTURES

WATERSHED POSITION

Faults and

sympathetic

fractures influence

movement of water

through the system

in shallow and deep

groundwater

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Upper Alum / Trench Camp

Load estimates calculated during base-flow conditions at

Trench Camp indicate that the discharge produces

approximately 20 lbs of combined metals (Cd+Co+Cu+Ni+Pb+Zn) per month; the

World’s Fair segment produces approximately 86 lbs of combined metals

(Cd+Co+Cu+Ni+Pb+Zn) per month.

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Perennial Evaporative Salt Accumulation

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Passive Treatment Systems Lead Queen Mine Patagonia, Arizona

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Stone Gabions with Zeolite Filters

Up and Downstream Long-Term Maintenance

Erosion Control and Rock

Barrier BMPs are expected

to last 5-10 years depending

on the rate of storm run-off.

Zeolite material replacement

frequency will be

determined as part of

implementation of the

project.

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Construction of gabion filter structure – Bagged zeolite core

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Construction of gabion filter structure – zeolite

exchange bed

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Construction of gabion filter structure – Rock armour

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Water flowing thru gabion structure

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Questions & Answers

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Acknowledgements

Donald Stevens, P.E.

Project Manager/Civil Engineer

Direct 916.706.3379 | Cell 559.824.8711

www.ECMConsults.com

Tristen McGee

HAZMAT Project Supervisor

Office 520.622.3607

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Floyd Gray

Research Geologist

US Geological Survey

(520) 670-5582

Floyd Gray (fgray@usgs.gov)

Jerry Hanley

CR Kendall Mine

Hilger, MT

Dale A. Shay

RIMCON, LLC

605-381-4515

rimcon@midconetwork.com

Contact Information

Daniel T. Eyde

St. Cloud Mining

520-744-8845

deyde@stcloudmining.com

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