1. Fitchburg, Massachusetts USA
In-Situ Thermal Remediation of Soil Contaminated with Organic Chemicals
Ralph S. Baker, Ph.D.
TerraTherm, Inc.
Fitchburg, Massachusetts USA
NATO/CCMS Pilot Study
Prevention and Remediation in Selected Industrial Sectors: Small Sites in Urban Areas
Athens, Greece
7 June 2006

2. Overview Introduction to In Situ Thermal Remediation (ISTD)
Steam-Enhanced Extraction
Electrical Resistance Heating
Thermal Conduction Heating
Representative Field Projects and Results
SEE – Aalborg, Denmark
TCH – Richmond, California, USA
Conclusion
Supplemental Data

3. Changes in Physical Properties with Heating (to 120°C)
20-100
20-80
20-300
2000
Thermal remediation has many beneficial effects that aid in the removal of creosote DNAPL and associated PAHs. These thermal remediation mechanisms have been described in detail by Udell (1996), Davis (1997), Imhoff et al. (1997), Sleep and Ma (1997), Heron et al. (1998a,b,c), and Stegemeier and Vinegar (2001). A brief summary is listed below:
Note: Per Stegemeier and Vinegar (2001), Vapor pressure increase factors should be: for oil based LNAPL: n-C16H24 and n-C29H60) ~8-80; for chlorinated solvents: ~15; for naphthalene ~300; for PCBs 1242 and 1260: Note also: only VOCs and light NAPL constituents (e.g., n-C16H24 and naphthalene) become volatile enough below 120C to be amenable to SVE.) Ask Gorm: Why are some values in red and others in black?
Conclude that for VOCs, vaporization is the dominant process, and capture of vapors and condensate is crucial – therefore complete heating and hydraulic and pneumatic control must be achieved
Udell (1989, 1991, 1993, 1996)
Davis (1997, 1999)
Imhoff et al. (1997)
Sleep and Ma (1997)
Heron et al. (1998, 2000)
Stegemeier and Vinegar (2001)
Note: Abiotic and biological reactions not listed

4. Consider In-Situ Thermal Remediation (ISTR):
For Source Remediation of Organic Contaminants (e.g., DNAPL)
To Facilitate a Brownfields Cleanup
To Achieve Rapid Site Closure
As part of overall optimization of an existing system, especially where additional source control/removal would significantly shorten the duration of a long-term pump and treat, SVE, or Multi-Phase Extraction system.

5. Steam Enhanced Extraction (SEE)
Steam, upper
Steam, lower
Extraction well
Example of steam flow and zone governed by low-K zone at 5-6 m depth. Monitoring and adjustments during heat-up important and expensive. Modeling for Fort Lewis proposal.

6. Electrical Resistance Heating (ERH)
Recovery
Six-Phase Heating: Electrical current moves between the 6 electrodes on the outside diameter and the central neutral.
Vertical Heated
Zone
Courtesy of CES
Three-Phase heating is another option
Horizontal Heated Zone Slightly Larger Than Array Diameter

7. Thermal Conduction Heating (TCH) Combined with Vacuum:
In-Situ Thermal Desorption (ISTD)
Heater Wells Are Spaced 6 to 25 Feet Apart and Operate at 1500°F
- To Remediate Recalcitrant SVOCs, Thermal Conduction Can Raise the Temperature Between Wells to 400°C when the Wells are Close Together
- If VOCs are to be Remediated, Well Spacing Can Be Much Farther Apart
- The Well Spacing Determines the Project Length
6 Feet ~ 45 Days (SVOCs),
25 Feet ~ 8 Months (VOCs)
Benzo(a)Pyrene BP 481° C Can Be Vaporized; Clays and Buried Cement are Not a Problem

8. NIRÁS SEE Project, Aalborg, Denmark
Former dry cleaning facility
 50 years of dry cleaning activity (~ )
 Perchloroethylene (PCE) and turpentine (stoddard solvent) as cleaning fluid
(Courtesy Tom Heron, NIRÁS)

9. Site layout and treatment wells
Østerbro Aalborg
Appartments
Former dry cleaner K a r o l i n e u d s v j
Shed
Ware
house
Garages
Railroad
Shop
Extraction well
Steam Injection well

10. Contaminant distribution
Former dry cleaning facility
1,0 m.b.g.
1,7 m.b.g.
Fillings
Sand
Clay
PCE
Turpentine
3,7 m.b.g.

11. Source zone & estimated mass
area 1
area 2
area 3

12. Remediation strategy ~ day 1-2
Ground water
Soil vapor
Steam
Steam
Former dry cleaning facility
Submerged pump
Fillings
Steam zone
Sand
Extraction well
Injection well
Clay
Steam zone

13. Remediation strategy ~ day 15
Ground water /free phase
Soil vapor /steam
Steam
Steam
Former dry cleaning facility
Submerged pump
Fillings
Steam zone
Sand
Extraction well
Clay
Injection well
Steam zone

14. Continous operation Temperature distribution 3,0 m.b.g. after 41 days
T3 T2 T1

15. Clean up results Removed ~ 900 - 1.000 kg of PCE/turpentine
Remaining contamination in cold spots: ~ kg
PCE in soil: 0, mg/kg
PCE in air: 1, mg/m3
PCE in water 0, µg/l
Efficiency: %
Remediation goal achieved: Threat to in- and outdoor air quality significantly reduced

16. Terminal One Project, San Francisco Bay Area, California

17. Target Treatment
Zone

18. Areas To Be Cleaned Up in Southwestern Tank Farm

19. Cross-Section Not to Scale
Richmond Site Cross-Section
5400 m3
CVOCs:
PCE, TCE,
DCE, and VC
NAPL
TTZ
Fill 0-1 m
Bay Mud
Target Treatment Zone (TTZ)
0 – 6.1 m
Cross-Section Not to Scale

20. – 126
– 12

21. Fiberglass Manifold Pipe
Horizontal
SVE Well HV
Well HO
Well

22. Heater-Vacuum (HV) Well
Sub Slab
Vapor Collection Point
Fiberglass Manifold Pipe TC
Pressure Monitoring Point
Heater-Only (HO)
Well

23. Richmond Results Reductions: 99.96% 99.63% 99.03% 99.49%
34,222
17,000
6,650
1,055
932
2,000
2,000
230 12
< RL 65 5
Reductions:
99.96%
99.63%
99.03%
99.49%
Results are based on 17 pre-treatment samples and 64 post-treatment samples.
Post-treatment samples were collected from centroids (i.e., coolest locations) at random and biased depths (15 or 23% were collected between 18 and 20 ft bgs).

24. Richmond Results Reductions: 99.96% 99.63% 99.03% 99.49%
510,000
57,000
6,500
6,500
2,000
2,000
17,000
230 44
< RL
1,500 24
Reductions:
99.96%
99.63%
99.03%
99.49%
Richmond results are based on 17 pre-treatment samples and 64 post-treatment samples.
Post-treatment samples were collected from centroids (i.e., coolest locations) at random and biased depths (15 or 23% were collected between 5.5 and 6.1 m bgs).

25. Projected Post Redevelopment View
350 Condominium Residential Area and
Waterfront Park Planned for Site

26. Project completed on time and on budget
7 months for construction and treatment
Total TT project cost: ~$1.7M
Cost of power: $250K
Post-development value: ~$300M
- Performance guaranteed
- Remedial goals achieved

27. ISTD Development and Deployment
PCBs 23
2006
CVOCs
CVOCs 22 21
CVOCs 19
Chlorinated
Benzenes, PAH, BTEX
ISTD Development and Deployment
2005 20
CVOCs 18
CVOCs 17
MGP 16
PAHs, Dioxins 15
2004
CVOCs 14 11
2003
CVOCs/SVOCs,
radionuclides 13 7 2
Chlorinated
Pesticides 13 19 16 20 12
2002 8 9
Chlorinated
Benzenes 11 14
PAHs 10 5 4
CVOCs 9 18 12 23
2001
Shell TerraTherm
TerraTherm, Inc. 3 15 21 22 17
2000 10
1999 1
PCBs 8
GRO/DRO, Benzene 7
PCBs
Saipan 6
1998
CVOCs 4
PCBs 5
PCBs 3
1997
Shell R&D
1980’s through 2000’s 1
PCBs 2
1996

28. TCH Research (Ongoing)1D 2D
1D tests to select and characterize soils for large-scale experiments
2D experiments on heat front propagation and DNAPL mobilization
Large-scale (150 m3) 3-D container experiments of TCH treatment of DNAPL under saturated conditions
Accompanying numerical simulations 3D
Upper Footprint of Container at VEGAS

29. Reerslev, Denmark Municipal Well Field
Threatened by nearby DNAPL source area, which is currently being considerated for ISTD.

30. Concluding Remarks
ISTR can be Tailored to the Needs of the Remediation Project
ISTR is Well-Suited to Small Urban Sites
ISTR is Rapid, Certain and Thorough, without the Drawbacks of Excavation
Clean to Residential Standards if Desired
Low Impacts to Neighbors
Cost-Competitive
Guarantees Available
Turn a Liability into an Asset!

31. About TerraTherm, Inc. Exclusive licensee of ISTD technology:
Within the U.S., from the Univ. of Texas at Austin. Protected by 24 U.S. patents.
Outside the U.S., from Shell Oil Co. Protected by 8 patents, and patents pending.
Sublicensees in Denmark and Sweden (Krüger A/S); U.K. (AIG Engineering Group, Ltd.)
International Partners in Denmark (NIRÁS); Germany (reconsite GmbH; VEGAS); and Japan (SheGoTec Japan, Inc.)
For more information, please visit

32. Supplemental Data Documented Results of Representative SEE, ERH and TCH Projects

33. Representative Steam Enhanced Extraction (SEE) Results
(Courtesy of G. Heron)

34. Representative Electrical Resistance Heating (ERH) Results
(Peacock et al. 2004; Cacciatore et al. 2004; Beyke et al. 2004; Hayes and Borochaner, 2004; Hoenig et al. 2004; Peterson et al. 2004)

35. Representative Thermal Conduction Heating (TCH) Results
Site
Major COCs
Depth (m)
Volume (m3)
Initial Max. Concentration (mg/kg)
Final Concentration (mg/kg)*
Cost ($/m3)
Confidential Mfg Site, OH
TCE
4.6
8800
4,130
< 0.07
180
Terminal One, Richmond, CA
PCE
6.1
5350
610
0.012
350
Shell Fuel Terminal, Eugene, OR
Benzene
Gasoline/ Diesel
3.7
13800
3.3
< 2.4 m free product
< 0.044
free product removed
260
Naval Facility Centerville Beach, Ferndale, CA
PCB
1180
800
< 0.17
550
National Grid,
N. Adams, MA
Naphthalene
B[a]P
5.5
780
679 20
5.7
0.33
1090
Southern California Edison, Alhambra, CA
PAH (B[a]P Eq.)
Dioxins (TEQ) 30
12400
30.6
0.018
0.059
570
Can meet more stringent goals than SEE or ERH
*All remedial goals met
(Stegemeier and Vinegar 2001; LaChance et al. 2004, 2006; Bierschenk et al. 2004)