Geophysics

Applications for

Environmental &

Engineering Problems

Geophysics

Applications for

Environmental &

Engineering Problems

Dale Rucker, PhD – Chief Technical Officer – drucker@hgiworld.com

Marc T. Levitt – Senior Project Manager - mlevitt@hgiworld.com

Service Offerings

Characterization and Monitoring for fluid Mine Heaps, Tailings, Waste Rock Plume Mapping

Leak Detection & Monitoring (LDM)

Secondary Recovery of Metal in Heaps

Underground Tanks

Environmental Site Characterization

Fracture Mapping

Engineering Site Characterization

Panama Canal

Sago Mine

Exploration

Copper and Gold

Uranium

Groundwater

Specializing in:

Our Philosophy

Every project involves some scientific research Requires some investigation on our part May require non-conventional use of geophysics Our work will pass peer review

We will be honest on the effectiveness of geophysics Not applicable to track dissolved-phase DNAPL (but

may be used to understand geology) Not applicable to map preferential flow paths in sat

zone Not applicable to find 10’ target, 300’ bgs from surface

measurements alone

Partial List of Pubs

Rucker, D.F., G.E. Noonan, and W.J. Greenwood, 2011. Electrical resistivity in support of geologic mapping along the Panama Canal. Engineering Geology 117(1-2):121-133

Rucker, D.F., J.B. Fink, and M.H. Loke, 2011. Environmental monitoring of leaks using time lapsed long electrode electrical resistivity. Journal of Applied Geophysics (accepted).

Rucker, D.F., M.H. Loke, G.E. Noonan, and M.T. Levitt, 2010. Electrical resistivity characterization of an industrial site using long electrodes. Geophysics 75:WA95-WA104.

Rucker, D.F., 2010. The application of magnetic gradiometry and electromagnetic induction at a former radioactive waste disposal site. Waste Management and Research 28(4):364-372.

Rucker, D.F., 2010. Moisture estimation within a mine heap: An application of cokriging with assay data and electrical resistivity. Geophysics 75(1):B11-B23.

Rucker, D.F., M.T. Levitt, and W.J. Greenwood, 2009. Three-dimensional electrical resistivity model of a nuclear waste disposal site. Journal of Applied Geophysics 69:150-164.

Rucker, D.F., M. McNeill, A. Schindler, and G.E. Noonan, 2009. Monitoring of a secondary recovery application of leachate injection into a heap. Hydrometallurgy 99(3-4):238-248.

Rucker, D.F., A. Schindler, M.T. Levitt, and D.R., Glaser, 2009. Three-dimensional electrical resistivity imaging of a gold heap. Hydrometallurgy 98(3-4):267-275.

Rucker, D.F., D.R. Glaser, T. Osborne, and W.C. Maehl, 2009. Electrical resistivity characterization of a reclaimed gold mine to delineate acid rock drainage pathways. Mine Water and Environment 28(2):146-157.

Rucker, D.F., 2009. A coupled electrical resistivity-infiltration model for wetting front evaluation. Vadose Zone Journal 8(2):383-388.

Greenwood, W.J. and D.F. Rucker, 2009. Marine resistivity survey of the Panama Canal. FastTimes 14(1): 43-47.

Partial List of Clients

Apollo Gold / JipanguAlamos GoldAnglo GoldBarrickFreeport McMoRanCoeur RochesterCotter CorporationInland ExplorationsKinross Gold Kennecott MiningNewmont MiningSago Mine

ARCADIS Brown & CaldwellClear Creek ConsultingCH2M Hill Montgomery & Assoc.Flour HanfordSRK Consulting TECTetra Tech URS Corporation

BLMFremont County SWDD (WY)Panama Canal AuthorityTucson International Airport U.S. Dept of EnergyU.S. EPA

What is Geophysics

1st Order: Target recognition tool Requires contrasts in physical

properties Collect sufficient “background”

Higher order analyses Topics of current research Relative degree of target size,

intensity Correlation to

hydro/geo/bio/chemical measurements

Uranium Targets on the Plateau

Scale

Planet / Continent Scale (105 - 107 m) Earthquake analysis Satellite-based instrumentation

Regional Scale (104 - 105 m) Airborne methods

Macro Site Scale (101 – 104 m) Surface methods

Micro Site Scale (10-2 – 101 m) Borehole methods

Innovations in Resistivity

Acquisition For specialized projects, we have our

own equipment Upscaled 3D (700+ stations) Rapid Monitoring Quality Assurance, NRC (NQA-1)

Processing Expanded hardware & software

Interpretation Integration of hydrology and

geophysics Contextual interpretation

Specialized System for Nuclear Waste Tank Monitoring

LDM Automated SystemLDM AutoPro and AutoView Software: Near Real Time Data Processing Automated Data Assessment Web Based for Remote Access Operations: 24/7 System Status Monitoring Daily Expert Visual Assessment

Specialized Methodology for Hanford LUSTs

• 54 Mgal waste stored in 177 tanks• Grouped into 12 tank farms• Single Shell Tanks supposed to have a 25 year life expectancy• 2010 minus 1943 = 67 years and counting

Typical Tank Farm

New Technique: Well-to-well

• Well-to-Well Summary:• Acquired data from 110 Wells•17 Ground water wells•93 Vadose zone wells•11,322 Data points• Data acquisition: 4 days• New algorithms developed

WTW resistivity

Advantage of using wells

Geophysical Methods for Mining

MethodsGravitySeismics

ElectromagneticsElectrical

IPMagnetics

RadarRadiometrics

PropertiesDensityStrength

ConductivityResistivity

CapacitanceSusceptibility

DielectricGamma

Exploration - Operations - Environment - Closure

Operations

Heaps Tailings Waste Rock Liners

Is solution getting in Is solution getting out Is it stable

APPLICATIONS

PROBLEMS

Issues Causing Poor Recovery from Heap Leach Pads

•Solution Management

•Side Slope Under-leaching

•Preferential Flow Pathways

•Compaction

•Migration of fines

•Heap settlement

•Clay zones

•Inadequate Ripping

•Chemical precipitation

Understanding Saturation

18

Plan Map of Gold Heap

1770

1780

1790

1800

1810

0 0.05 0.1 0.15

Log Gold (opt)

Moisture (g/g)

Ele

vatio

n(m

)1770

1780

1790

1800

1810

0 0.05 0.1 0.15

Ele

vatio

n(m

)

Log Gold (opt)

Moisture (g/g)

Assay Data

Water is an easy parameter to measure Direct Indirect

Direct drilling shows: Variability at small scale

Line 1

Line 2

Line 3

Line 4

Line 5

Line 6

Line 7

Line 8

Line 9

Line 10

Line 11

Line 12

HJ-1

HJ-2

HJ-3

HJ-4

HJ-5

HJ-6

HJ-7

HJ-8

HJ-9

HJ-10

HJ-11

HJ-12

HJ-13

HJ-14

HJ-15

HJ-16

HJ-17

HJ-18

HJ-19

HJ-20

HJ-21

HJ-22

HJ-23

HJ-24

HJ-25

HJ-29

HJ-30

HJ-31

HJ-32

290400 290600 290800 291000 291200 291400 291600 291800 292000

Easting (State Plane NAD27 Feet)

2262200

2262400

2262600

2262800

2263000

2263200

2263400

2263600

2263800

2264000

2264200

No

rth

ing

(Sta

teP

lan

eN

AD

27F

eet

)

State Plane - NAD27 - Feet

MAP LEGEND................ 3D HRR Area....... HydroJex Drillholes.. HRR Calibration Wells....... Lift Level Boundary......... HydroJex Surface Electrodes... HRR Characterization Surface Electrodes

0 50 100

150

200

250

Resistivity Example

0 50 100 150 200 250 300 350 400

1780

1800

0.8

1

1.2

1.4

1.6

1.8

2

2.2

2.4

2.6

2.8

3

0 50 100 150 200 250 300 350 400

1780

1800

Line 6

Line 7

west east log resHJ-32 HJ-19

HJ-24 HJ-20 HJ-16

Calibration

0

0.01

0.02

0.03

0 0.02 0.04 0.06 0.08 0.1

y = 0.0744x + 0.0112

R2 = 0.73

0.02 0.03

Moisture

Con

du

ctiv

ity

(S/m

)1730

1740

1750

1760

1770

1780

1790

1800

0 0.02 0.04 0.06 0.08 0.1Moisture (g/g)

HJ-24

0.01 0.02 0.03Electrical Conductivity (S/m)

HJ-32

0 0.01 0.02 0.03Electrical Conductivity (S/m)

1740

1750

1760

1770

1780

1790

1800

1810

0 0.02 0.04 0.06 0.08 0.1Moisture (g/g)

Specialized System for Mining

Data from high pressure injections

Liner Leak Location

Fluid Filled Lined Ponds

Heap Leach Pads

electrical location of leaks

28240

28250

28260

28270

28280

28290

28300

28310

No

rth

ing

(fe

et)

50790 50800 50810 50820 50830 50840 50850

Easting (feet)

T207

T208

LOCALIZED LEAK AREAS(confirmed)

High Wall

Liner Leak Location

Liner Leak Location

e-e-

e-

e- e-

e-

Tx

e- e-e-

e-

e-

e-

e-e-

e-

e-e-

e-

Tx

e-

Single Liner

Double Liner

Closure / Reclamation

Acid rock drainage Acidic waters leaving site

From pit From piles

Low pH water will mobilize heavy metals Usually ends up in sensitive water areas Good target for resistivity

Abandoned mine lands Subsidence Contamination Good targets for gravity, seismic

Reclaimed Gold Mine

It is suspected that ARD is migrating from Suprise and Queen Rose Pit Area to Swift Gulch

Landusky

Migration of ARD is likely structurally controlled

Results

Results

0 100 200 300Distance (m)

1350

1400

1450

1500

1550

1600

Ele

vati

on(m

)

frac

ture

frac

ture

frac

ture

Gol

dB

ugS

hear

1.51.7

1.92.1

2.32.5

2.72.9

3.13.33.5

3.73.9

Removed Material

Pre-mine Topo

Water Table

log Resistivity(ohm-m)

Fracture (low certainty)

Fracture (high certainty)

Pre-mine Topo

Mine Topo

Suprise Pit

Queen Rose Pit

Reclamation Topo

West East

Supr

ise

She

ar

GCL in SupriseGCL in Queen Rose

GCL Location

Results

0 100 200 300 400 500

Distance (m)

1325

1350

1375

1400

1425

1450

1475

Ele

vati

on(m

)

drai

nage

drai

nage

drai

nage

drai

nage

Log Resistivity (ohm-m)

1.51.71.92.12.32.52.72.93.13.33.53.73.9

0 100 200 300 400 500

1325

1350

1375

1400

1425

1450

1475

Ele

vati

on(m

)

drai

nage

drai

nage

drai

nage

Fracture (low certainty)

Fracture (high certainty)

Topo

Line 10

Line 11

Water Table

Water Table

BKSP1

BKSP2(N,E,U)

Approx. projection of RPM Seep Electrode

Results – 3D

Looking Overhead fromSouthwest

666,500

667,000

408,600

408,800Eastin

g (m) Northing

(m)

1400

1450

1500

Elevation

(m)

HRR LineStream or Drainage

Seep used for ResistivityMeasurement

Well

409,000

Swift Gulch

Results – 3D

EC = 4.796x10 * TDS + 0.0013-7

R2 = 0.8541

0

0.001

0.002

0.003

0.004

0.005

0.006

0 1000 2000 3000 4000 5000 6000 7000 8000 9000

Total Dissolved Solids (mg/L)

Ele

ctri

calC

ondu

ctiv

ity

from

Mod

el(S

/m)

ZL-204 ZL-403

ZL-314

ZL-401

ZL-404ZL-405

Panama Canal

Canal is expanding Current=4000 containers Expanded=10,000 cont.

Expansion will include Widening Dredging

Dredging efficiency Type of rock Strength of rock Volume of rock

Marine Resistivity

Gamboa Reach

Results

Geotechnical Mapping

Geotechnical Mapping

Geologic Mapping

First Phase: Site Clearance

Second Phase: Fault and fracture mapping

Resistivity Results

Resistivity

EOR Monitoring

Surfactant Injection at RMOTC – Teapot Dome (WY)

Unattended monitoring for 4 month period

Obtained formation hydraulic conductivity

Identified possible barriers to flow

-0.002

0.000

0.002

0.004

0.006

0.008

0.010

0.012

0.014

1 10 100 1000 10000

Time (minutes)

Ele

ctri

cal r

esp

on

se

Well 63S response

exponential fit (63S)

Well 65SX response

exponential fit (65SX)

Well 63SRecovery time = 10 hrs

Well 65SXRecovery time = 1.0 hrs

0.000

0.002

0.004

0.006

0.008

0.010

0.012

0.014

0.016

0.018

0.020

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

Time (de cimal days)

Ele

ctr

ical

Res

po

nse

(d

imen

sio

nle

ss)

Inje

ctio

npe

riod

(line

ar)

Recoveryperiod (exponential)

Background period(~0.002 units)

Buried Object Detection

Buried Water Well Casing

GEM-2 In Phase response

Final Words…

Sometimes unique solutions are needed for characterizing and monitoring sites

HGI has a good background in geology, hydrogeology, engineering, and resource evaluation to provide solutions

We have worked on some very unique problems But have the ability, interest, and pricing model to

work on more routine problems