Completion of In-Situ Thermal Completion of In-Situ Thermal Remediation of PAHs, PCP and Remediation of PAHs, PCP and Dioxins at a Former Wood Dioxins at a Former Wood Treatment Facility Treatment Facility Ralph S. Baker, Ph.D., Ralph S. Baker, Ph.D., John M. Bierschenk, John M. Bierschenk, P.G., P.G., James P. Galligan, P.E., and Ron Young James P. Galligan, P.E., and Ron Young TerraTherm, Inc., Fitchburg TerraTherm, Inc., Fitchburg, Massachusetts, USA Massachusetts, USA March 29, 2007 March 29, 2007
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Ralph S. Baker, Ph.D., John M. Bierschenk, P.G., James P. Galligan, P.E., and Ron Young
Completion of In-Situ Thermal Remediation of PAHs, PCP and Dioxins at a Former Wood Treatment Facility. Ralph S. Baker, Ph.D., John M. Bierschenk, P.G., James P. Galligan, P.E., and Ron Young TerraTherm, Inc., Fitchburg , Massachusetts, USA March 29, 2007. Sketch of ISTD Process. - PowerPoint PPT Presentation
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Completion of In-Situ Thermal Completion of In-Situ Thermal Remediation of PAHs, PCP and Remediation of PAHs, PCP and
Dioxins at a Former Wood Dioxins at a Former Wood Treatment FacilityTreatment Facility
Ralph S. Baker, Ph.D.,Ralph S. Baker, Ph.D., John M. Bierschenk, P.G., John M. Bierschenk, P.G., James P. Galligan, P.E., and Ron YoungJames P. Galligan, P.E., and Ron Young
TerraTherm, Inc., FitchburgTerraTherm, Inc., Fitchburg, Massachusetts, USAMassachusetts, USA
March 29, 2007March 29, 2007
Power distribution system
Vapor treatment
Knockout pot
Blower
Water treatmentDischarge
Heater and vacuum wells
Treated vapor to atmosphere
Heat exchanger
Pump
Treatment area foot-print
Temperature and pressure monitoring holes (1 of many)
Sketch of ISTD ProcessSketch of ISTD Process
Power Supply
ISTD is the Simultaneous Application of:• Thermal Conduction Heating (TCH)• Vapor Recovery
What Makes Thermal What Makes Thermal Conduction Heating (TCH) so Conduction Heating (TCH) so
Unique?Unique? The Thermal Conductivity of a Wide Range of Soil Materials The Thermal Conductivity of a Wide Range of Soil Materials
(gravel, sand, silt, clay) Varies Only by a Factor of ~3(gravel, sand, silt, clay) Varies Only by a Factor of ~3 By Contrast:By Contrast:
TCH Heaters Can Be Readily Controlled, to Achieve Low, TCH Heaters Can Be Readily Controlled, to Achieve Low, Moderate or Higher Soil Temperatures as NeededModerate or Higher Soil Temperatures as Needed
.
ISTD Thermal WellsISTD Thermal Wells
Heater-VacuumWell
Process Trailer
Heater-Only Wells
Heater-Vacuum Well
Hexagonal Well Pattern
Heater-Only Well
Heater-Vacuum Well
Thermal DestructionZone
Typical Heating Progression Typical Heating Progression for Various Levels of ISTD Treatmentfor Various Levels of ISTD Treatment
Contrasting Applications of Contrasting Applications of ISTD/TCHISTD/TCH
Level of Level of Heating and Heating and Contaminant Contaminant TypeType
Target Target Treatment Treatment
TemperatureTemperature
((°°C)C)
Thermal Thermal Well Well
SpacingSpacing
(m)(m)
Desiccate Desiccate Target Target
Treatment Treatment ZoneZone
(TTZ)?(TTZ)?
Range of Range of Costs Costs
(Turnkey)*(Turnkey)*
($/m($/m3))
1. VOCs: 1. VOCs: GentleGentle
Heating**Heating** (BTEX, CVOCs)(BTEX, CVOCs)
<100<100 >6>6 NoNo 40-240*40-240*
2. VOCs2. VOCs (BTEX, CVOCs)(BTEX, CVOCs) 100100 4-74-7 Not Not
Target temperature (treatability results) of Target temperature (treatability results) of 335335C (635C (635F), maintained for 3 days F), maintained for 3 days
2.1-m thermal well spacing2.1-m thermal well spacing
785 thermal wells, total (131 heater-vacuum 785 thermal wells, total (131 heater-vacuum and 654 heater-only wells)and 654 heater-only wells)
Insulated surface sealInsulated surface seal
Two treatment phasesTwo treatment phases
Aerial View – December 2004Aerial View – December 2004
Phase 1
Phase 2
Thermal Well Fields InstalledThermal Well Fields Installed
Phase 1 Phase 2
Air Quality Control System Air Quality Control System 24/7 Continuous Manned Operation24/7 Continuous Manned Operation
Monitoring Well Field Temperatures & Vacuum, Monitoring Well Field Temperatures & Vacuum, Continuous Emissions Monitoring (CEM) of Off-Gas Continuous Emissions Monitoring (CEM) of Off-Gas System Parameters System Parameters
Well Field Layout and Well Field Layout and Representative Centroid Representative Centroid
LocationsLocations
Phase 1 Phase 1 CentroidCentroid
Tem
per
atur
e °F
0
100
200
300
400
500
600
700
800
6/11
/200
3
7/1/
2003
7/20
/200
3
8/7/
2003
8/26
/200
3
10/1
1/20
03
11/6
/200
3
12/2
/200
3
12/2
8/20
03
1/14
/200
4
2/9/
2004
3/4/
2004
6:0
0
4/17
/200
4
T7A4B-4BHK19-4-8
Temperature °F
Date
Description
Target Treatment Temperature 635°F
Vaporization of Water Complete, Start of
Superheating
Attainment of Target Treatment
Temperature
Heater Circuits Shut Down, Start of Well
Field Cool-Down
4/17/2004
3/4/2004
2/9/2004
1/14/2004
12/28/2003
12/2/2003
11/6/2003
10/11/2003
8/26/2003
8/7/2003
7/20/2003
7/1/2003
6/11/2003
0
100
200
300
400
500
600
700
800
6/11
/200
3
7/1/
2003
7/20
/200
3
8/7/
2003
8/26
/200
3
10/1
1/20
03
11/6
/200
3
12/2
/200
3
12/2
8/20
03
1/14
/200
4
2/9/
2004
3/4/
2004
6:0
0
4/17
/200
4
T7A4B-4BHK19-4-8
Temperature °F
Date
Description
Target Treatment Temperature 335°C
Vaporization of Water Complete, Start of
Superheating
Attainment of Target Treatment
Temperature
Heater Circuits Shut Down, Start of Well
Field Cool-Down
4/17/2004
3/4/2004
2/9/2004
1/14/2004
12/28/2003
12/2/2003
11/6/2003
10/11/2003
8/26/2003
8/7/2003
7/20/2003
7/1/2003
6/11/2003
Phase 2 Phase 2 CentroidCentroid
Tem
per
atur
e °F
0
100
200
300
400
500
600
700
800
900
6/22
/200
4 18
:00
7/14
/200
4 8:
00
8/4/
2004
6:0
0
9/3/
2004
16:
00
10/5
/200
4 14
:30
11/8
/200
4
12/1
2/20
04 2
2:30
1/12
/200
5 8:
00
2/6/
2005
3/3/
2005
14:
00
3/26
/200
5
4/17
/200
5 8:
00
5/11
/200
5 6:
30
6/7/
2005
6/30
/200
5 16
:00
7/23
/200
5
8/13
/200
5 14
:30
9/5/
2005
0:0
1
9/27
/200
5
11/1
7/20
05 7
:00
T11A2-2HG13-4-5
Temperature °F
Description
Target Treatment Temperature 635°F
Vaporization of Water Complete, Start of
Superheating
Attainment of Target
Treatment Temperature
635°F
Heater Circuits Shut Down, Start of Well Field Cool-
Down
11/17/2005
9/27/2005
9/5/2005
8/31/2005
7/23/20056/30/2005
6/7/2005
5/11/2005
4/17/2005
3/26/2005
3/3/20052/6/2005
1/12/2005
12/12/2004
11/8/2004
10/5/2004
9/3/20048/4/2004
7/14/2004
6/22/2004
0
100
200
300
400
500
600
700
800
900
6/22
/200
4 18
:00
7/14
/200
4 8:
00
8/4/
2004
6:0
0
9/3/
2004
16:
00
10/5
/200
4 14
:30
11/8
/200
4
12/1
2/20
04 2
2:30
1/12
/200
5 8:
00
2/6/
2005
3/3/
2005
14:
00
3/26
/200
5
4/17
/200
5 8:
00
5/11
/200
5 6:
30
6/7/
2005
6/30
/200
5 16
:00
7/23
/200
5
8/13
/200
5 14
:30
9/5/
2005
0:0
1
9/27
/200
5
11/1
7/20
05 7
:00
T11A2-2HG13-4-5
Temperature °F
Description
Target Treatment Temperature 335°C
Vaporization of Water Complete, Start of
Superheating
Attainment of Target
Treatment Temperature
335°C
Heater Circuits Shut Down, Start of Well Field Cool-
Down
11/17/2005
9/27/2005
9/5/2005
8/31/2005
7/23/20056/30/2005
6/7/2005
5/11/2005
4/17/2005
3/26/2005
3/3/20052/6/2005
1/12/2005
12/12/2004
11/8/2004
10/5/2004
9/3/20048/4/2004
7/14/2004
6/22/2004
Coke from product zone
Auger cuttings oxidation vs. pyrolysis
Confirmatory sampling in
well field
~5.5 m bgs
~2.7 m bgs
~0.3 m bgs
0.0
0.1
1.0
10.0
100.0
1,000.0
10,000.0
100,000.0
Pre Treatment Post Treatment
Mea
n C
on
cen
trat
ion
(u
g/k
g)
B(a)P Equivalent
Dioxins (2,3.7,8-TCDD TEQ)
Cleanup Goals
65 g/kgB(a)P
1g/kgDioxin
30,600
18
0.11
N = 60N = 47
59
Comparison of Pre- and Post-Comparison of Pre- and Post-Treatment Contaminant Treatment Contaminant
ConcentrationsConcentrations
Summary Summary Site demob. completed March 2006Site demob. completed March 2006 Estimated mass removed via combustion (oxidizer Estimated mass removed via combustion (oxidizer
and subsurface) 395,000 kg (COand subsurface) 395,000 kg (CO22 method) method) Additional mass destroyedAdditional mass destroyed in situ in situ by pyrolysis (dark by pyrolysis (dark
soil/coke) soil/coke) Air emissions were well below compliance Air emissions were well below compliance
requirements requirements Post–treatment soil sampling results all below Post–treatment soil sampling results all below
stringent clean-up requirements stringent clean-up requirements No Further Action letter (February 7, 2007) from No Further Action letter (February 7, 2007) from
California Department of Toxic Substances Control California Department of Toxic Substances Control to Southern California Edison allows unrestricted to Southern California Edison allows unrestricted land useland use
Cost Implications of Lessons Learned Cost Implications of Lessons Learned for Future Applications of ISTD at for Future Applications of ISTD at
Creosote SitesCreosote Sites Achievement of unrestricted/residential land use by an Achievement of unrestricted/residential land use by an in-situ remediation method is achievable and practical in-situ remediation method is achievable and practical
ISTD was initially compared and selected over ISTD was initially compared and selected over excavation with offsite incineration excavation with offsite incineration
ISTD remediation costs exceeded original estimates; ISTD remediation costs exceeded original estimates; however, all-in project cost was still ~40% lower than however, all-in project cost was still ~40% lower than the excavation alternativethe excavation alternative
TerraTherm’s estimate for similar site of 12,600 mTerraTherm’s estimate for similar site of 12,600 m33, , with one 130-day treatment is $500/mwith one 130-day treatment is $500/m33:: Capital cost: $3.9MCapital cost: $3.9M Operations, source testing, and electricity: $2.2MOperations, source testing, and electricity: $2.2M Demobilization, reporting, licensing fee: $0.23MDemobilization, reporting, licensing fee: $0.23M