Cleanup of Small Dry Cleaner Cleanup of Small Dry Cleaner Using Multiple Technologies: Using Multiple Technologies:

Sages Dry Cleaner SiteSages Dry Cleaner Site

NATO/CCMS Pilot Study Meeting, June 2006NATO/CCMS Pilot Study Meeting, June 2006

Guy W. Sewell, Ph.D.Guy W. Sewell, Ph.D.Professor of Environmental Health SciencesProfessor of Environmental Health Sciences

Robert S. Kerr Endowed ChairRobert S. Kerr Endowed ChairEast Central UniversityEast Central University

Large Small

Waste Type Mixed PH/CH

Access Issues flexible less

Boundary Issues some many

NA-applicable yes less likely

Ownership Gov./Corp. Private

Time Issues Varies Limited by economics

Site Size IssuesSite Size Issues

Small Urban Sites are more likely to require source zone treatment to meet remedial time limitations and coordinated remedial approaches to address both source zone and dissolved phase contaminants.

Field Evaluation of the Solvent Extraction Residual Biotreatment (SERB) Technology

Project Team USEPA-NRMRL-SPRD-Ada

•Guy W. Sewell, PI, Biological Processes•Lynn Wood, Physical Processes•Susan Mravik, Site Coordinator•Ann Keeley, Norma Duran (Lab Studies)

Site Contractor•Levine-Fricke Recon

UF•Mike Annable, PI Solvent Extraction

MSU•James M. Tiedje, PI Microbial Ecology•Shannon Flynn, Rebekah Helton, Frank Loeffler (Lab Studies)

Project Funding- SERDP(FIBRC-WES), EPA-TIO, State of Florida

OBJECTIVE• Integrate Remediation Technologies into a

Treatment Train for Comprehensive Site Restoration• Target DNAPL Source Zone• Decrease Remediation Costs

LIMITATIONS• Geology• Source Zone Delineation• Time (?)

CONTAMINANT OF INTEREST:

Tetrachloroethene (PCE)

TECHNOLOGICAL BASIS:

Cosolvent Extraction (Ethanol)

Biodegradation (Reductive Dechlorination)

DNAPL

GW Flow

Residual & Separate Phase Material

PCE Spill

GW Flow

90%+ Mass Removal

Cosolvent ExtractionInjection WellEthanol Flush

RecoveryWell

PCE

Ethanol Mixed

Restoration?, Risk Reduction?

GW Flow

Residual Contaminants

Bioremediation

Bioactive Zone

FNA, Dissolution < Assimilative Capacity

GW Flow

Why SERB (Source Control)

• Remove more mobile fraction of DNAPL, lower dissolved concentrations. Reduce time/distance needed to meet GW quality objectives.

• Activate reductive bio-transformations in high redox environments.

• Insure supply of e- donor, accelerate process and reduce uncertainty.

• Regulatory requirement.

Biotransformations forChloroethenes

PCE

cis -DCEtrans -DCE

Vinyl Chloride

Ethene

TCE

1,1-DCE

CO2

CO2Ethane

CO2

X

X

Some fieldevidence

No evidence but - G

No evidence but -G

Reductive Transformation

Oxidative Catabolism

ANAEROBIC OXIDATION-REDUCTION

Electron AcceptorsElectron Donors

OrganicCompoundEtOH, H

2

PartiallyOxidized

Compound(s)

acetate CO2

3NO -

SO 4=

Fe 3+

HCO 3-

R-Cl x

N 2(NH 4+)

H 2SFe 2+CH 4R-Clx-1

SEWELL, '95Reduced Electron Acceptors

Chloroethene Sites

Plume Type Bio-attenuation Stable• Parent Dominant No Yes

(PCE or TCE)

• VC/cis DCE Yes NoDominant

• Ethene Forming Yes ?

Field Test of the SERB Technology

Sages Dry Cleaner Site

Results and Discussion

Field Test Table of Events• July, 1998 Site Characterization, Ground Water Monitoring, &

Partitioning Tracer Test

• Aug. 9-15, 1998 Ethanol Flush (9000 gallons)

• Aug. 15, 1998 Partitioning Tracer Test Start Hydraulic Containment

• Aug. 25, 1998 End Hydraulic Containment Ethanol < 10,000 mg/L

Sage’s Dry Cleaner SiteJacksonville, Florida

RW-006RW-007

C1C2

C3C4MW-505

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RW-002

RW-003 RW-004

RW-005

CONCRETESLAB

ASPHALT

DNAPLAREA

0 ft. 20 ft. 40 ft. 60 ft. 80 ft.

Pre-Cosolvent Flush Site Characterization

• Aerobic Conditions

• Low levels of daughter products (TCE)

• DNAPL contamination identified at 26 to 31 ft. bgs

Figure 1. PCE and ethanol concentrations during co-solventflood at Sages Site in recovery well RW-001.

Cosolvent Flush Performance

Pre-Cosolvent Flush Partitioning Tracer 44.3 L (PCE)

Post-Cosolvent Flush Partitioning Tracer 13.9 L (PCE)

Estimated Recovery Based onPartitioning Tracer Tests 30.4 L (PCE)

(70%)

Mass Recovery Based on PCEConcentrations in Recovery Wells 41.5 L (PCE)

0

2

4

6

8

10

12

14

16

18

20

Jan-98 Jan-99 Jan-00 Jan-01 Jan-02 Jan-03 Jan-04

Date

Mon

thly

Pre

cipi

tatio

n (in

ches

)

35

35.5

36

36.5

37

37.5

Elev

atio

n (fe

et)

0.003

0.006

0.009

0.008

0.003

0.003

0.0010.001

0.0010.001

0.006

0.004

0.0002

- 0.001

0.002

0.0020.002

0.001

0.009

Ground Water (Avg)

Canal

EthanolEthanol

0 mM

50 mM

100 mM

150 mM

200 mM

250 mM

300 mM

350 mM

350 mM = 16 g/L = 1.6 %

C1C2

C3C4

C7

MW-505

MW-506

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~1 Month Post-Flush

C1C2

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C7

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MW-506

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MW-512MW-513MW-514

~2 Months Post-Flush

C1C2

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C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~3.5 Months Post-Flush

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~5.5 Months Post-Flush

EthanolEthanol

0 mM

50 mM

100 mM

150 mM

200 mM

250 mM

300 mM

350 mM

350 mM = 16 g/L = 1.6 %

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~13.5 Months Post-Flush

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~19 Months Post-Flush

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~22 Months Post-Flush

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~9.5 Months Post-Flush

EthanolEthanol1000 mM = 4.6 g/L = 0.46 %

0 mM

25 mM

50 mM

75 mM

100 mM

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~40 Months Post-Flush

C1C2

C3C4

C7

MW-505

MW-506

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MW-509MW-510MW-511

MW-512MW-513MW-514

~35 Months Post-Flush

C1C2

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C7

MW-505

MW-506

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MW-509MW-510MW-511

MW-512MW-513MW-514

~31 Months Post-Flush

C1C2

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~28 Months Post-Flush

EthanolEthanol1000 mM = 4.6 g/L = 0.46 %

0 mM

25 mM

50 mM

75 mM

100 mMC1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~45 Months Post-Flush

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~50 Months Post-Flush

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~56 Months Post-Flush

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~62 Months Post-Flush

PCEPCE

0 uM

50 uM

100 uM

150 uM

200 uM

250 uM

300 uM

350 uM

400 uM

450 uM

500 uM

500 uM = 83 mg/L

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

Pre-Ethanol Flush

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~1 Month Post-Flush

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~3.5 Months Post-Flush

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~2 Months Post-Flush

PCEPCE

0 uM

50 uM

100 uM

150 uM

200 uM

250 uM

300 uM

350 uM

400 uM

450 uM

500 uM

500 uM = 83 mg/L

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~5.5 Months Post-Flush

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~9.5 Months Post-Flush

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~13.5 Months Post-Flush

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510

MW-511

MW-512MW-513MW-514

~19 Months Post-Flush

PCEPCE

0 uM

50 uM

100 uM

150 uM

200 uM

250 uM

300 uM

350 uM

400 uM

450 uM

500 uM

500 uM = 83 mg/L

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510

MW-511

MW-512MW-513MW-514

~22 Months Post-Flush

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~25 Months Post-Flush

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510

MW-511

MW-512MW-513MW-514

~28 Months Post-Flush

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~31 Months Post-Flush

PCEPCE

0 uM

50 uM

100 uM

150 uM

200 uM

250 uM

300 uM

350 uM

400 uM

450 uM

500 uM

500 uM = 83 mg/L

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~50 Months Post-Flush

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~56 Months Post-Flush

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~62 Months Post-Flush

C1C2

C3C4

C7

MW-505

MW-506

MW-507

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~65 Months Post-Flush

TCETCE

0 uM

10 uM

20 uM

30 uM

40 uM

50 uM

60 uM

70 uM

80 uM

90 uM

100 uM

100 uM = 13 mg/L

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

Pre-Ethanol Flush

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~1 Month Post-Flush

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~2 Months Post-Flush

C1C2

C3C4

C7

MW-505

MW-506

MW-507

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MW-512MW-513MW-514

~3.5 Months Post-Flush

TCETCE

0 uM

10 uM

20 uM

30 uM

40 uM

50 uM

60 uM

70 uM

80 uM

90 uM

100 uM

100 uM = 13 mg/L

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~5.5 Months Post-Flush

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~9.5 Months Post-Flush

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~13.5 Months Post-Flush

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~19 Months Post-Flush

TCETCE

0 uM

10 uM

20 uM

30 uM

40 uM

50 uM

60 uM

70 uM

80 uM

90 uM

100 uM

100 uM = 13 mg/L

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~50 Months Post-Flush

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~56 Months Post-Flush

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~62 Months Post-Flush

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~65 Months Post-Flush

ciscis-DCE-DCE

0 uM

25 uM

50 uM

75 uM

100 uM

125 uM

150 uM

175 uM

175 uM = 17 mg/L

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

Pre-Ethanol Flush

C1C2

C3C4

C7

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MW-506

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~1 Month Post-Flush

C1C2

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MW-512MW-513MW-514

~2 Months Post-Flush

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~3.5 Months Post-Flush

ciscis-DCE-DCE

0 uM

25 uM

50 uM

75 uM

100 uM

125 uM

150 uM

175 uM

175 uM = 17 mg/L

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~22 Months Post-Flush

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510

MW-511

MW-512MW-513MW-514

~25 Months Post-Flush

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~28 Months Post-Flush

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~31 Months Post-Flush

ciscis-DCE-DCE

0 uM

25 uM

50 uM

75 uM

100 uM

125 uM

150 uM

175 uM

175 uM = 17 mg/L

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~50 Months Post-Flush

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~62 Months Post-Flush

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~65 Months Post-Flush

C1C2

C3C4

C7

MW-505

MW-506

MW-507

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~56 Months Post-Flush

Vinyl ChlorideVinyl Chloride2.0 uM = 125 ug/L

0.0 uM

0.2 uM

0.4 uM

0.6 uM

0.8 uM

1.0 uM

1.2 uM

1.4 uM

1.6 uM

1.8 uM

2.0 uM

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~28 Months Post-Flush

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~31 Months Post-Flush

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~35 Months Post-Flush

C1C2

C3C4

C7

MW-505

MW-506

MW-507

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MW-512MW-513MW-514

~40 Months Post-Flush

Vinyl ChlorideVinyl Chloride2.0 uM = 125 ug/L

0.0 uM

0.2 uM

0.4 uM

0.6 uM

0.8 uM

1.0 uM

1.2 uM

1.4 uM

1.6 uM

1.8 uM

2.0 uM

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510

MW-511

MW-512MW-513MW-514

~42 Months Post-Flush

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~45 Months Post-Flush

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~50 Months Post-Flush

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~56 Months Post-Flush

Vinyl ChlorideVinyl Chloride2.0 uM = 125 ug/L

0.0 uM

0.2 uM

0.4 uM

0.6 uM

0.8 uM

1.0 uM

1.2 uM

1.4 uM

1.6 uM

1.8 uM

2.0 uM

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~62 Months Post-Flush

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~65 Months Post-Flush

EtheneEthene

0.0 uM

0.1 uM

0.2 uM

0.3 uM

0.4 uM

0.5 uM

0.5 uM = 14 ug/L

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~50 Months Post-Flush

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~56 Months Post-Flush

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~62 Months Post-Flush

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~65 Months Post-Flush

ChlorideChloride

0 uM

250 uM

500 uM

750 uM

1000 uM

1250 uM

1500 uM

1750 uM

2000 uM

2250 uM

2250 uM = 80 mg/L

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~50 Months Post-Flush

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~56 Months Post-Flush

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~62 Months Post-Flush

C1C2

C3C4

C7

MW-505

MW-506

MW-507

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MW-512MW-513MW-514

~65 Months Post-Flush

Acetic AcidAcetic Acid

0 uM

200 uM

400 uM

600 uM

800 uM

1000 uM

1200 uM

1400 uM

1600 uM

1600 uM = 96 mg/L

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~56 Months Post-Flush

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~62 Months Post-Flush

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~65 Months Post-Flush

SulfateSulfate

0 uM

100 uM

200 uM

300 uM

400 uM

500 uM

600 uM

700 uM

800 uM

900 uM

900 uM = 86 ug/L

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~56 Months Post-Flush

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~62 Months Post-Flush

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~65 Months Post-Flush

MethaneMethane

0 uM

100 uM

200 uM

300 uM

400 uM

500 uM

600 uM

700 uM

800 uM

900 uM

1000 uM

1100 uM

1100 uM = 18 mg/L

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~1 Month Post-Flush

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~2 Months Post-Flush

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~3.5 Months Post-Flush

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~5.5 Months Post-Flush

MethaneMethane

0 uM

100 uM

200 uM

300 uM

400 uM

500 uM

600 uM

700 uM

800 uM

900 uM

1000 uM

1100 uM

1100 uM = 18 mg/L

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~56 Months Post-Flush

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~62 Months Post-Flush

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~65 Months Post-Flush

C1C2

C3C4

C7

MW-505

MW-506

MW-507

MW-509MW-510MW-511

MW-512MW-513MW-514

~22 Months Post-Flush

SUMMARYSolvent Extraction:

41.5 L PCE Removed (Mass Recovery)~70 % PCE Removed (Partitioning Tracer)

PCE Daughter Product FormationTCE, cis-DCE, VC, ethene, methane (?)

Change in GeochemistryDissolved Oxygen, Sulfate, and Redox

Indications of Biological ActivityMethane, Volatile Fatty Acid, and Hydrogen

Partial Oxidation of Ethanol:CH3CH2OH + H2O -----> CH3COOH + 2 H2

Complete Oxidation of Ethanol: CH3CH2OH + 3H2O -----> 2CO2 + 6 H2

Dechlorination of PCE:C2ClX + H2 -----> C2Clx-1 + H+ + Cl-

Complete Dechlorination of PCE Requires1-2 Moles of Ethanol

(excluding competing processes)

Source Area = 40 ft. diameter X 5 ft. depthAssume Porosity = 0.4Pore Volume = 70,000 LConcentrations:

Average Ethanol = 8,000 mg/LAverage PCE = 50,000 ug/L

Total Mass:Ethanol - 570 Kg or 12,350 MolesPCE - 3.6 Kg or 21.5 Moles

Theoretically, we have >250 times the amount of ethanol present for complete dechlorination of the estimated remaining PCE.38.8 times the amount needed to degrade the 157.1 moles of the (estimated) PCE in the source zone (136 moles residual PCE + 21.1 moles dissolved PCE). While this estimate assumes no competing terminal oxidation processes such as methanogenesis or sulfate reduction, an efficiency greater that 2% would still meet the theoretical demand.

cis-DCE Formation

y = 52.7 xR2 = 0.61

y = 1.1 x

y = 10.3 x

0

10000

20000

30000

40000

50000

60000

70000

-200 0 200 400 600 800 1000 1200

Time (Days)

Concentration (ug/L)

C2C3MW-510MW-514RW-007

R2 = 0.49

R2 = 0.68

First Order Degradation Rates (Based on Total Mass)

Ethanol -0.33 year-1 (R2 0.53) t ½ = 2.1 yrs

PCE -0.56 year-1 (R2 0.82) t ½ = 1.2 yrs

cis-DCE 0 .81 year-1 (R2 0.82) t ½ = 0.9 yrs

Total Chlorides

0

20

40

60

80

100

120

0 1 2 3 4 5 6

Time (Years)

Moles CL

Organic ClInorganic ClTotal

• Currently the system remains biologically active and the dechlorination products are accumulating.

• High levels of dissolved methane and hydrogen have also been detected in the treatment zone.

• The maximum and minimum observed rate of dechlorination (based on cis-DCE production) are approximately 43.6 and 4.2 ug/liter/day, respectively.

• These rates can be extrapolated to a multi-step, concurrent, dechlorination process to predict that the dissolved phase PCE could be removed in 3 to 30 years, and that the total source zone PCE could be transformed in 24 to 240 years.

Publications

Sewell, G.W. et al. 2005. Chlorinated Solvent Contaminated Soil and Ground Water: Field Application of the Solvent Extraction Residual Biotreatment Technology, Chapter 5. In Bioremediation of Recalcitrant Compounds. Taylor & Francis Publishers, Boca Raton. Pp 59-149.

Mravik, S., R.K.Sillan, A.L. Wood, and G.W. Sewell. 2003. Field Evaluation of the Solvent Extraction Residual Biotreatment (SERB) Technology. Environ. Sci. Technol. 37: 5040-5049.

Jawitz, J., R.K. Sillan, M.D. Annable, P.S.C. Rao and K. Warner. 2000. In-Situ Alcohol Flushing of a DNAPL Source Zone at a Dry Cleaner Site. Environ. Sci. Technol. 34: 3722--3729.

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