Abiotic / Biotic Treatability Study

Restoration Advisory Board Meeting

January 14, 2010

Installation Restoration Sites 26 and 28

2

IR Site 26 Treatability Study

Purpose of Treatability Test

Determine if combined abiotic/biotic treatment is a viable remedial alternative for mitigating the remaining chlorinated ethenes (CEs) present in the upper portion of the A-aquifer at IR Site 26.

Conduct Pilot Test in area of highest CE concentration in upper A-Aquifer at Site 26

Treatability Study Method:

Pilot Test Method:

Install wells in Pilot Test area

Determine baseline conditions in pilot test area

Inject EHC® into Aquifer

Measure Distribution of EHC®

Measure changes in pilot test area geochemistry

Measure changes in pilot test area CE concentrations

Hypothesized Reaction Pathways

Biotic AbioticPCE

TCE

Cis 1,2-DCE Trans 1,2-DCE

VC

Ethene

Ethane

PCE

TCE

VC

Ethene

Ethane

Chloroacetylene

Acetylene

1,1-DCE, trans 1,2-DCE, cis1,2-DCE

Dichloroacetylene

Hydrogenolysis

β-elimination

α-elimination

Hydrogenation

C4

C4 compounds

5

Indicators of Degradation Pathway

• Chloroacetylene

• Dichloroacetylene

Abiotic Pathway

• Acetylene

• 1,1-DCE

Biotic Pathway

• Primarily cis 1,2-DCE

• Low TCE, DCE, VC / ethene ratio• Stoichiometric Conversion

Tetrachloroethene (PCE)

Trichloroethene (TCE)

Dichloroethene (DCE)

Radius of EHC Distribution Evaluation

5.0

5.5

6.0

6.5

7.0

7.5

8.0

-30 0 30 60 90 120 150

Co

ncen

trati

on

(S

U)

Days (Day 0 = May 27, 2009)

pH

W-AB-1

W-AB-2

W-AB-3

W-AB-4

W-AB-5

WU5-24

EXW-1

-250

-200

-150

-100

-50

0

50

100

150

200

250

-30 0 30 60 90 120 150

Co

ncen

trati

on

(m

V)

Days (Day 0 = May 27, 2009)

Oxidation-Reduction Potential

W-AB-1

W-AB-2

W-AB-3

W-AB-4

W-AB-5

WU5-24

EXW-1

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

-30 0 30 60 90 120 150

Co

ncen

trati

on

(m

g/L

)

Days (Day 0 = May 27, 2009)

Dissolved Oxygen

W-AB-1

W-AB-2

W-AB-3

W-AB-4

W-AB-5

WU5-24

EXW-1

0

1

2

3

4

5

6

7

8

-30 0 30 60 90 120 150

SC

(m

S/c

m)

Days (Day 0 = May 27, 2009)

Specific Conductance

W-AB-1

W-AB-2

W-AB-3

W-AB-4

W-AB-5

WU5-24

EXW-1

0

2,000

4,000

6,000

8,000

10,000

12,000

14,000

16,000

18,000

20,000

-30 0 30 60 90 120 150

Co

ncen

trati

on

(u

g/L

)

Days (Day 0 = May 27, 2009)

Methane

W-AB-1

W-AB-2

W-AB-3

W-AB-4

W-AB-5

WU5-24

EXW-1

0

10

20

30

40

50

60

-30 0 30 60 90 120 150

Co

ncen

trati

on

(m

g/L

)

Days (Day 0 = May 27, 2009)

Manganese

W-AB-1

W-AB-2

W-AB-3

W-AB-4

W-AB-5

WU5-24

EXW-1

0

50

100

150

200

250

-30 0 30 60 90 120 150

Co

ncen

trati

on

(m

g/L

)

Days (Day 0 = May 27, 2009)

Sulfate

W-AB-1

W-AB-2

W-AB-3

W-AB-4

W-AB-5

WU5-24

EXW-1

0

5

10

15

20

25

30

35

40

-30 0 30 60 90 120 150

Co

ncen

trati

on

(u

g/L

)

Days (Day 0 = May 27, 2009)

Arsenic

W-AB-1

W-AB-2

W-AB-3

W-AB-4

W-AB-5

WU5-24

EXW-1

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

-30 0 30 60 90 120 150

Co

nc

en

tra

tio

n (u

mo

l/L

)

Days (Day 0 = May 27, 2009)

Ethenes & Ethane- Molar ConcentrationAverage Inside Treatment Area

(WA-B-2, WU5-24, EXW-1)

PCE

TCE

Total DCE

VC

Ethene

Ethane

Total Ethenes & Ethane

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

-30 0 30 60 90 120 150

Co

nce

ntr

ati

on

(u

mo

l/L

)

Days (Day 0 = May 27, 2009)

Ethenes & Ethane- Molar ConcentrationAverage Outside of Treatment Area

(WA-B-1, WA-B-3, WA-B-4, WA-B-5)

PCE

TCE

Total DCE

VC

Ethene

Ethane

Total Ethenes & Ethane

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

-30 0 30 60 90 120 150

Co

nc

en

tra

tio

n (

um

ol/

L)

Days (Day 0 = May 27, 2009)

Ethenes & Ethane - Molar Concentration

Average Downgradient of Treatment Area(WA-B-1, WA-B-3, WA-B-4, WA-B-5)

PCE

TCE

Total DCE

VC

Ethene

Ethane

Total Ethenes & Ethane

0.0

0.1

0.2

0.3

0.4

0.5

0.6

-30 0 30 60 90 120 150

Co

ncen

trati

on

(u

mo

l/L

)

Days (Day 0 = May 27, 2009)

W-AB-3 (Upgradient, 7 to 17 ft bgs) Ethenes & Ethane - Molar Concentration

PCE

TCE

Total DCE

VC

Ethene

Ethane

Total Ethenes & Ethane

EXW-1

W-AB-3

W-AB-2

WU5-24

Tre

atm

en

t A

rea

We

lls

Up

gra

die

nt

We

ll

Relative Fraction of CEs, Ethene and Ethane

Relative Fraction of CEs, Ethene and Ethane

W-AB-1

W-AB-4

W-AB-5

Do

wn

gra

die

nt

We

lls

25

Preliminary Conclusions Site 26 TS

• pH, ORP, SC, T, in the treatment area are within the range considered appropriate for biotic and abiotic degradation of the CEs

• DO, nitrate, arsenic, manganese, iron, sulfate and methane reducing conditions have been established in the treatment area.

• Degradation of CEs is occurring.

• Cis 1,2-DCE stall is not occurring.

• Dechlorinating microbial culture (DHC) is present in the treatment area.

• Complete conversion of CEs to non-toxic degradation products is occurring.

26

26 Treatability Study Schedule

January, 5, 2010 -2nd Quarter GW Sampling Event

March 29, 2010 – 3rd Quarter GW Sampling Event

June 28, 2010 – 4th Quarter GW Sampling Event

August 25, 2010 -Draft Treatability Study Results Technical Memorandum

October 27, 2010 -Final Treatability Study Results Technical Memorandum

27

Conduct Concurrent Pilot Tests in Three Areas:

Evaluate Three Technologies:

In Situ Anaerobic Biotic/Abiotic Degradation (ISABA)

In Situ Anaerobic Biostimulation with Bioaugmentation (ISABB) Process

Building 88 Area

Traffic Island Area

Well W9-18 Area

Sodium Lactate & SDC-9

Emulsified Oil & SDC-9

Expanded Pilot Test (Site 28) Methodology

EHC

Well W9-19

ISABA - EHC

ISABB - Emulsfied Oil & SDC-9

ISABB - Lactate & SDC-9

Task 1

Conduct MIPs Investigation

Task 2

Install Monitoring Wells

Task 3

Inject Substrates

Expanded Pilot Test Site 28

29

Site 28 Pilot Test Schedule

February 2010 - Work Plans Finalized

March 2010 - MIPs Investigation

May 2010 -Treatability Study Progress Report

July, 2010 - Substrate Injection

August 2010 to July 2011 - Performance Monitoring

October 2011 – Treatability Study Final Report

June, 2010 – Monitoring Well Installation