FATE OF CONTAMINANTS IN UNCONSOLIDATED AQUIFERS

THOUGHTS ON DETERMINING THE RELEVANT PHYSICAL TRANSPORT PROCESSES AT FIELD SITES

Denis LeBlanc

Toxic Substances Hydrology Program

With Contributions from:

Brian Andraski, Barbara Bekins, Scott Christenson, Isabelle Cozzarelli, Fred Day-Lewis, Geoff Delin, Bill Herkelrath, Mary Hill, Randy Hunt,

Jim Landmeyer, John Lane, Michelle Lorah, Jason Masoner, Roger Morin, Tom Reilly, Don Rosenberry, Allen Shapiro, Byron Stone,

Dave Stonestrom, and Don Walter (USGS)

Rose Forbes (AFCEE), Graham Fogg

(UCDavis), Kamini

Singha

(Penn State),

Chunmiao

Zheng

(UAlabama), Brewster Conant (UWaterloo), Pete Shanahan (MIT), and Dick Willey and Kathy Hess (USEPA)

Understanding the flow system is critical•

Geohydrologic

framework

•

Sources and sinks of water•

Local and regional boundaries

•

Patterns and rates of flow

MADE site, MSMADE site, MS

Naval Air Warfare CenterNaval Air Warfare Center

(NAWC), NJ(NAWC), NJ

Circular 1224

“Homogeneous” unconsolidated aquifers continue to pose challenges

Talk Outline•

Hydrogeologic framework

•

Flow patterns and discharge •

Heterogeneity and transport

•

Future directions

Laurel Bay, SCLaurel Bay, SC

Amargosa

Desert Research Site, NV

I. Hydrogeologic

Framework Geologic framework relevant to transport at different scales

1 ft

Sea

Level

400 ft

-

400 ft

4 mi

Examples from Cape Cod, MA

1,000 ft

100

ft

Bedrock

Water table

I. Hydrogeologic

Framework Geological models to define hydraulic framework

Dep

ostio

nal

feat

ure

LnK

LLNL Arroyo Seco

Alluvial Fan, CA (Fogg)

5 km

Sea

Level

400 ft

-

400 ft

Glacial outwash

Western Cape Cod

0 50 100 150 200 250 300 350 400 450 500 550 600 650 700 750 800 850 900 950 1000 1050 1100 1150

Traverse Distance westing (m)

750

800

850

Elev

atio

n N

AVD

29 (m

)

20

406080

100120140

160180

200220240

260280300

Resistivity (Ohm-m)

Gravel layers (based on DC resistivity) containing peak contaminant concentrations

Amargosa

Desert

I. Hydrogeologic

Framework Geophysical methods to define hydrogeologic framework

Ambient noise

passive seismic

Passive seismic

Boreholes

Outer Cape Cod Seismic refraction

I. Hydrogeologic

Framework Inverse modeling to improve aquifer representation

Western

Cape Cod

Model parameters

Sen

sitiv

ity

Slough

used to Map the Biogeochemical Zones

3837

Landfill

Slo

ugh

35 54 55 80

DOC <50 mg/L

Aerobic Zone- Oxygenated RechargeSulfur Recycled, SO4

2- and Fe (III) reductionAnoxic Zone & slough discharge, Anoxic Zone, DOC >60 mg/LAnoxic groundwater, DOC >85 mg/LMethanogenic, depleted sulfate

Conceptual model of redox zones at Norman Landfill

0

5

Met

ers

0 50 100Meters

Cozzarelli et al., GSA 2000

AA’

used to Map the Biogeochemical Zones

3837

Landfill

Slo

ugh

35 54 55 80

DOC <50 mg/L

Aerobic Zone- Oxygenated RechargeSulfur Recycled, SO4

2- and Fe (III) reductionAnoxic Zone & slough discharge, Anoxic Zone, DOC >60 mg/LAnoxic groundwater, DOC >85 mg/LMethanogenic, depleted sulfate

Aerobic Zone- Oxygenated RechargeSulfur Recycled, SO4

2- and Fe (III) reductionAnoxic Zone & slough discharge, Anoxic Zone, DOC >60 mg/LAnoxic groundwater, DOC >85 mg/LMethanogenic, depleted sulfate

Conceptual model of redox zones at Norman Landfill

0

5

Met

ers

0 50 100Meters

Cozzarelli et al., GSA 2000

AA’

II. Flow Patterns and Discharge Local hydrologic boundaries can control plume paths

Norman Landfill, OKNorman Landfill, OK

II. Flow Patterns and Discharge Stable isotopes to define ground-water flow paths

Cape Cod

1,000 ft

Tetrachloroethene

(μg/L)

20 ft

Aberdeen Proving Grounds, MD

IR image

20 ft

II. Flow Patterns and Discharge Temperature surveys to locate focused discharge

20 mCape Cod fiber optics

Cold GW discharge

Cape CodDiffusion samplerDiffusion sampler

II. Flow Patterns and Discharge Discharge can be key to understanding flow paths

MicrowellMicrowell

Cranberry bogCranberry bog

EDB plume

II. Flow Patterns and Discharge Rapid sampling methods allow plume path delineation

Cass Lake, MN

Direct-push profiles

New well clusters

Benzene plume in 2006

III. Heterogeneity and Transport Small-scale heterogeneity affects transport

Aerial View of Bemidji, MNAerial View of Bemidji, MN

Electrical resistivity tomographyElectrical resistivity tomography

III. Heterogeneity and Transport Geophysical methods to describe heterogeneity

Cape Cod

ERT wells

Injection wellInjection well

Tracer cloud

III. Heterogeneity and Transport Macrodispersion related to heterogeneity

Cape Cod Tracer Test

1 ft

2 (ln K) < 1

55

60

ZA

xis(m

)

050

X Axis (m)0

50100

150200

250

Y Axis (m)

3001005025105

Concentration(pCi/mL)

55

60

ZA

xis(m

)

0

50

X Axis (m) 0

50

100

150

200

250

Y Axis (m)

X

Y

Z

55

60

ZA

xis(m

)

0

50

X Axis (m) 0

50

100

150

200

250

Y Axis (m)

X

Y

Z

328 days

No pref. paths

Observed

12% pref. paths

Mobile domain

Immobile domain

MADE tracer tests (Zheng)

2 (ln K) > 4

III. Heterogeneity and Transport Dual domain model may be needed for high heterogeneity

IV. Future DirectionsIntegration of transport processes along entire flow path

190

190

189

188187

187

1

189

190

190

189

190

189188

185

188187

187

187

186

185

185

189

188

186

187

187

187

186

186

AngusPlaza

PlazaWell

Pine

Riv

er

Bridge

Railroad Tracks

Former Railroad Tracks

Curtis

St.

Queen St.

King Street

Simcoe St.

Cro

ss

St.

Wa t

er S

t.

DryCleanerBuilding

Nor

th

MainStudy AreaFor River

Ground elevation contour (amsl)EXPLANATION

Waterloo Profiler Location0 40 m

PCEPlume

B5B1B2

B3SC13

SC12RC12

SC11

190

175

180

185

PineRiver

Dry CleanerBuilding

(projected)

Cla

y B

erm

SoutheastNorthwest

SAND

SAND

SAND

SAND

SAND ?

?

?

?

?

?

Fill PotentiometricSurface

SAND

SAND

Elev

atio

n m

?

Angus Geologic Cross Section

?

SILT,CLAY

& PEATSAND

?

?

- 40 24020016012080400Distance m

EXPLANATIONSoil Cored IntervalWaterloo Profiler Location

SILT & CLAY AQUITARD?

Angus, Ontario, PCE plume (Conant)

Extent ofVOC Plume

cDCE614

461920

33

North

Extent ofVOC Plume

PCE

1433

15537

817

Total VOCs1479

5529 263668

34

Shore

IV. Future Directions Incorporation of uncertainty in simulation and prediction

Western Cape Cod

Final Thoughts

Directions for Future Research

•

Use of geological information to define aquifer framework and fabric

•

Methods to characterize heterogeneity at relevant scales

•

Integrated effects of physical and geochemical heterogeneity

•

Interaction of ground-water flow with NAPL-contaminated zones

•

Transport in the unsaturated zone

Successful site cleanup depends on a sound conceptual model and application of basic hydrologic principles and tools

•

Inverse modeling methods as practical tools at field sites

•

Incorporation of uncertainty in the understanding of hydrologic systems

Slide Item Sources of information and images 2 MADE site, MS

NAWC site, NJ Circular 1224

Zheng, Chunmiao, 2008, Understanding solute transport in extremely heterogeneous porous media—Lessons learned from 25 years of research at the MADE site—2009 Birdsall-Dreiss Distinguished Lecturer, Geological Society of America, Hydrogeology Division: GSA Today, v. 18, no. 10, p. 14 [ftp://rock.geosociety.org/pub/GSAToday/gt0810.pdf]

U.S. Geological Survey, 2009, Geochemical and microbiological processes that

affect migration and natural attenuation of chlorinated solvents in fractured sedimentary rock—Naval Air Warfare Center (NAWC) Research Site, West Trenton, NJ: Accessed online December 10, 2009, at http://nj.usgs.gov/nawc/index.htm

Focazio, M.J., Reilly, T.E., Rupert, M.G., and Helsel, D.R., 2002, Assessing

ground-water vulnerability to contamination: Providing scientifically defensible information for decision makers: U.S. Geological Survey Circular 1224, 33 p. [http://pubs.usgs.gov/circ/2002/circ1224/]

3 Amargosa Desert site, NV Laurel Bay, SC

U.S. Geological Survey, 2009, Amargosa Desert research site: Accessed online December 10, 2009, at http://nevada.usgs.gov/adrs/

U.S. Geological Survey, 2009, Oxygenated fuel -- Laurel Bay, South Carolina site:

Accessed online December 10, 2009, at http://toxics.usgs.gov/sites/laurel_bay/laurel_page.html

4 Geologic framework, Cape Cod, MA

Masterson, J.P., Stone, B.D., Walter, D.A., and Savoie, Jennifer, 1997, Hydrogeologic framework of western Cape Cod, Massachusetts: U. S. Geological Survey Hydrologic-Investigations Atlas HA 741, 1 plate.

Slide Item Sources of information and images 5 Geological models,

Cape Cod, MA LLNL Arroyo Seco alluvial fan, CA

Masterson, J.P., Stone, B.D., Walter, D.A., and Savoie, Jennifer, 1997, Hydrogeologic framework of western Cape Cod, Massachusetts: U. S. Geological Survey Hydrologic-Investigations Atlas HA 741, 1 plate.

Walter, D.A., and LeBlanc, D.R., 2008, Use of inverse modeling methods to

improve ground-water-modeling calibration and evaluate model-prediction uncertainty, Camp Edwards, Cape Cod, Massachusetts: U.S. Geological Survey Scientific Investigations Report 2007-5257, 57 p. [http://pubs.usgs.gov/sir/2007/5257/]

Fogg, G.E., 2002, A geologic approach to simulation of subsurface hydrology—

2002 Birdsall-Dreiss Distinguished Lecturer, Geological Society of America, Hydrogeology Division: GSA Today, v.18, no. 10, p. 14 [ftp://rock.geosociety.org/pub/GSAToday/gt0810.pdf]

Fogg, G.E., Carle, S.F., and Green, Christopher, 2000, Connected-network

paradigm for the alluvial aquifer system, in Zhang, Dongxiao, and Winter, C.L., eds., Theory, modeling, and field investigation in hydrogeology—A special volume in honor of Shlomo P. Neuman’s 60th birthday: Boulder, CO, Geological Society of America, Special Paper 348, p. 25-42.

Fogg, G.E., Noyes, C.D., and Carle, S.F., 1998, Geologically based model of

heterogeneous hydraulic conductivity in an alluvial setting: Hydrogeology Journal, v. 6, no. 1, p. 131-143.

6 Ambient noise passive seismic method Amargosa Desert site, NV

U.S. Geological Survey, 2009, Horizontal-to-vertical spectral ratio seismic method technology demonstration and evaluation project: Accessed online December 10, 2009, at http://water.usgs.gov/ogw/bgas/hvseismic/

U.S. Geological Survey, 2009, Amargosa Desert research site: Accessed online

December 10, 2009, at http://nevada.usgs.gov/adrs/

7 Inverse modeling Cape Cod, MA

Walter, D.A., and LeBlanc, D.R., 2008, Use of inverse modeling methods to improve ground-water-modeling calibration and evaluate model-prediction uncertainty, Camp Edwards, Cape Cod, Massachusetts: U.S. Geological Survey Scientific Investigations Report 2007-5257, 57 p. [http://pubs.usgs.gov/sir/2007/5257/]

Slide Item Sources of information and images 8 Norman Landfill, OK U.S. Geological Survey, 2009, Biogeochemical and geohydrologic processes in a

landfill-impacted alluvial aquifer, Norman, Oklahoma: Accessed online December 10, 2009, at http://ok.water.usgs.gov/projects/norlan/

9 Defining groundwater flow paths J-3 Range plume, Cape Cod, MA

LeBlanc, D.R., Massey, A.J., Cochrane, J.J., King, J.H., and Smith, K.P., 2008, Distribution and migration of ordnance-related compounds and oxygen and hydrogen stable isotopes in ground water near Snake Pond, Sandwich, Massachusetts, 2001-2006: U.S. Geological Survey Scientific Investigations Report 2008-5052, 19 p. [http://pubs.usgs.gov/sir/2008/5052/]

10 Aberdeen Proving Grounds, MD Cape Cod, MA

Majcher, E.H., Phelan, D.J., Lorah, M.M., and McGinty, A.L., 2007, Characterization of preferential ground-water seepage from a chlorinated hydrocarbon-contaminated aquifer to West Branch Canal Creek, Aberdeen Proving Ground, Maryland, 2002–04: U.S. Geological Survey Scientific Investigations Report 2006–5233, 191 p. [http://pubs.usgs.gov/sir/2006/5233/].

U.S. Geological Survey, 2009, Fiber-optic distributed temperature sensing

technology demonstration and evaluation project: Accessed online December 10, 2009, at http://water.usgs.gov/ogw/bgas/fiber-optics/

11 Flow patterns and discharge Cape Cod, MA

Savoie, J.G., LeBlanc, D.R., Blackwood, D.S., McCobb, T.D., Rendigs, R.R., and Clifford, Scott, 2000, Delineation of discharge areas of two contaminant plumes by use of diffusion samplers, Johns Pond, Cape Cod, Massachusetts, 1998: U.S. Geological Survey Water-Resources Investigations Report WRIR 00-4017, 30 p.

12 Cass Lake, MN Herkelrath, W.N., Delin, G.N., and Cozzarelli, I.M., 2008, Using peristaltic bailing to obtain ground water samples in push probe profiling of a subsurface BTEX plume: Boulder, CO, Geological Society of America Abstracts with Programs, 2088 Annual Meeting, v. 40, no. 6, p. 343 [http://gsa.confex.com/gsa/2008AM/ finalprogram/abstract_148335.htm]

U.S. Geological Survey, 2009, Cass Lake crude-oil spill: Accessed online

December 28, 2009, at http://mn.water.usgs.gov/projects/ description/8607CXW.html

13 Bemidji site, MN U.S. Geological Survey, 2009, Bemidji crude-oil research project: Accessed online December 10, 2009, at http://mn.water.usgs.gov/projects/bemidji/index.html

Slide Item Sources of information and images 14 Geophysical methods and heterogeneity

Cape Cod, MA Singha, Kamini, and Gorelick, S.M., 2005, Saline tracer visualized with three-

dimensional electrical resistivity tomography—Field-scale spatial moment analysis: Water Resources Research, v. 41, W05023, 17 p. [doi:10.1029/2004WR0034600].

Singha, Kamini, and Gorelick, S.M., 2006, Hydrogeophysical tracking of three-

dimensional tracer migration—The concept and application of apparent petrophysical relations: Water Resources Research, v. 42, W06422 [doi:10.1029/2005WR004568].

U.S. Geological Survey, 2009, Mapping aquifer heterogeneity-- Integrated analysis

of geophysical and hydraulic data at the Massachusetts Military Reservation, Cape Cod, Massachusetts: Accessed online December 11, 2009, at http://water.usgs.gov/ogw/bgas/toxics/mmr_ert.html

15 Macrodispersion and heterogeneity Cape Cod, MA

LeBlanc, D.R., Garabedian, S.P., Hess, K.M., Gelhar, L.W., Quadri, R.D., Stollenwerk, K.G., and Wood, W.W., 1991, Large-scale natural-gradient tracer test in sand and gravel, Cape Cod, Massachusetts: 1. Experimental design and observed tracer movement: Water Resources Research, v. 27, no. 5, p. 895-910.

Hess, K.M., Wolf, S.H., and Celia, M.A., 1992, Large-scale natural gradient tracer

test in sand and gravel, Cape Cod, Massachusetts: 3.Hydraulic-conductivity variability and calculated macrodispersivities: Water Resources Research, v. 28, no. 8, p. 2011-2027.

Hess, K.M., Wolf, S.H., and Celia, M.A., 1992, Large-scale natural gradient tracer

test in sand and gravel, Cape Cod, Massachusetts: 3.Hydraulic-conductivity variability and calculated macrodispersivities: Water Resources Research, v. 28, no. 8, p. 2011-2027.

U.S. Geological Survey, 2009, Cape Cod Toxic Substances Hydrology research

site: Accessed online December 10, 2009, at http://ma.water.usgs.gov/CapeCodToxics/

Slide Item Sources of information and images 16 MADE site, MS Zheng, Chunmiao, and Gorelick, S.M., Analysis of solute transport in flow fields

influenced by preferential flowpaths at the decimeter scale: Ground Water, v. 41, no. 2, p. 142-155.

Harvey, C.F., and Gorelick, S.M., 2000, Rate-limited mass transfer or

macrodispersion: Which dominates plume evolution at the Macrodispersion Experiment (MADE) site?: Water Resources Research, v. 36, no. 3, p. 637–650.

Boggs, J.M., Beard, L.M., Long, S.E., McGee, M.P., MacIntyre, W.G., Antworth,

C.P., and Stauffer, T.B., 1993, Database for the second macrodispersion experiment (MADE-2): California, Electric Power Research Institute, TR-102072.

17 Angus PCE plume, ON Conant Jr., B., Cherry, J.A., and Gillham, R.W., 2004, A PCE groundwater plume discharging to a river—Influence of the streambed and near-river zone on contaminant distributions: Journal of Contaminant Hydrology, v. 73, no. 1-4, p. 238-279.

Conant Jr., B., 2004, Delineating and quantifying ground-water discharge zones using streambed temperatures: Ground Water, v. 42, no. 2, p. 243-257.

18 Uncertainty in simulation and prediction Cape Cod, MA

Walter, D.A., and LeBlanc, D.R., 2008, Use of inverse modeling methods to improve ground-water-modeling calibration and evaluate model-prediction uncertainty, Camp Edwards, Cape Cod, Massachusetts: U.S. Geological Survey Scientific Investigations Report 2007-5257, 57 p. [http://pubs.usgs.gov/sir/2007/5257/]