Pilot Study: Evaluation of ISCO on TCE Impacted Ground Water Residing in Granitic Mass
Mauricio H. Escobar, P.G., ENVIRON International Corporation, Los Angeles, CA

Phase III ISCO with Catalyzed Persulfate of Chloro Benzenes in Glacial Till and Bedrock, Corinna, ME
Ian T. Osgerby, USACE New England District, Concord MA

Chemical Oxidation of Sulfa Drugs, Barbiturates and Chlorinated Solvents in Groundwater: A Bench Test Evaluation   
Neal D. Durant, Geosyntec Consultants, Columbia, MD

Site Remediation of Chlorinated Solvent Contaminated Groundwater via In Situ Application of Activated Persulfate
Philip Block, FMC Corporation, Philadelphia, PA

Treatment of Non-Aqueous Phase Liquids (NAPLs) using Surfactant-Enhanced In-Situ Oxidation (S-ISCO®)
George E. Hoag, VeruTEK Technologies, Inc., Glastonbury, CT

Control of MnO₂ Particles during Permanganate-ISCO through Use of Chemical Stabilization Aids

Saebom Ko, Ph.D., Department of Environmental Health, East Tennessee State University, PO Box 70682, Johnson City, TN 37614, Tel: 423-439-5249, Fax: 423-439-5230, Email: ko@etsu.edu
Michelle Crimi, Ph.D., Department of Environmental Health, East Tennessee State University, PO Box 70682, Johnson City, TN 37614, Tel: 423-439-7066, Fax: 423-439-5230, Email: crimi@etsu.edu
Mark Quickel, Department of Environmental Health, East Tennessee State University, PO Box 70682, Johnson City, TN 37614, Tel: 423-439-7639, Fax: 423-439-5230, Email: ZMTQ2@imail.etsu.edu
Bradley Martin, Department of Environmental Health, East Tennessee State University, PO Box 70682, Johnson City, TN 37614, Tel: 423-439-7639, Fax: 423-439-5230, Email: bradley_martin1@yahoo.com
Hilary Cartwright, Department of Environmental Health, East Tennessee State University, PO Box 70682, Johnson City, TN 37614, Tel: 423-439-7639, Fax: 423-439-5230, Email: hilarypaige1@yahoo.com

In-situ chemical oxidation (ISCO) has been widely applied to remediate groundwater, soil, and sediment contaminated by organic compounds, such as PCE, TCE, BTEX, etc. Among various chemical oxidants, permanganate is relatively stable than other oxidants, thus, it has been successfully delivered to contact with contaminants in various subsurface environments. Interesting phenomenon associated with permanganate-ISCO is the formation of MnO₂ particles which can precipitate and accumulate in porous media, resulting in a loss of permeability and hydraulic conductivity and a reduction of organic compound degradation efficiency. In order to improve mass transfer and to prevent permeability reduction, it is necessary to control the excessive accumulation of MnO₂ particles in porous media.

The goal of this research is to understand the genesis and control of MnO₂ particles and to identify the MnO₂ particle stabilization aids that will allow for their transport in groundwater through porous media under a variety of reaction conditions. Bench-scale experimental studies using 12mL reaction vials were conducted to examine reaction conditions that affect the formation of _MnO2 particles. These conditions include (1) particle concentration, (2) pH, (3) ionic variation, (4) solid content, (5) redox conditions, and (6) stabilization aid types and concentrations. These conditions are evaluated through spectrophotometric analyses at wavelengths 418nm and 525nm; particle filtration at various membrane sizes; and optical measurements for particle size and zeta potential. 1-D transport experiments in column (2.5cm ID × 60cm) are in progress to study particle transport in varied porous media- (1) sand only, (2) sand + organic matter, (3) sand + clay, (4) sand + iron oxides, and (5) sand + organic matter + clay + iron oxides. This presentation will highlight results of the effectiveness of four chemical stabilization aids to control MnO₂ particles under various reaction conditions and particle transport studies in column.

Pilot Study: Evaluation of ISCO on TCE Impacted Ground Water Residing in Granitic Mass 

Mauricio H. Escobar, P.G., ENVIRON International Corporation, 707 Wilshire Boulevard, Suite 4950, Los Angeles, CA  90017, Tel: 213-943-6337, Fax: 213-943-6301
Antony Jones, Ph.D., ENVIRON International Corporation, 2010 Main Street, 9th Floor, Irvine, CA  92614, Tel: 949-798-3615, Fax: 949-261-6202
Carol Serlin, P.G., ENVIRON International Corporation, 2010 Main Street, 9th Floor, Irvine, CA  92614, Tel: 949-798-3660, Fax: 949-261-6202

Injection of sodium permanganate has been proven as a promising remedial application used to treat chlorinated solvents in ground water, particularly in sedimentary environments. An oxidant injection pilot study was designed to introduce sodium permanganate solution into decomposed and fractured granitic rock saturated with TCE impacted ground water.  To treat TCE concentrations as high as 18,000 µg/l, between 500 and 600 gallons of 10% solution were pressure injected via 47 multi-depth permanent oxidant delivery probes.  The pilot study’s primary objectives were to assess the effectiveness of sodium permanganate to oxidize TCE in ground water under site-specific conditions, quantify the radius of influence associated with injection wells and injection methodology, investigate the attenuation of TCE in soil gas overlying and originating from impacted ground water, and characterize possible rebound effects following injection.  Secondary effects associated with injection of sodium permanganate were also investigated, including changes in the mobility and toxicity of naturally occurring metals in ground water and impacts to native microbial populations. 

Baseline, process, and performance monitoring was conducted over a 4 month period using a well network consisting of 30 monitoring wells and 18 soil gas probes.  Data collection included low-flow ground water sampling for laboratory chemical analyses, and collection of water level elevations and water quality parameters using downhole dataloggers and multiparameter water quality probes.  Throughout implementation of the pilot study, manual water level measurements and permanganate concentrations using a field colorimeter were recorded.  The results of the pilot study provided a site-specific assessment of the remedial efficacy and risks associated with injection of sodium permanganate to treat TCE-impacted ground water in decomposed and fractured granitic rock. 

Phase III ISCO with Catalyzed Persulfate of Chloro Benzenes in Glacial Till and Bedrock, Corinna, ME

Ian T. Osgerby PhD PE, US Corps of Engineers New England District, 696 Virginia Rd., Concord Ma 01742, Tel: 978-318-8631, Fax: 978-318-8614, Email: ian.t.osgerby@usace.army.mil
Kenneth L. Sperry, P.E., Regional Manager, XDD, LLC, 101 East Mill Street, Suite D, Quakertown, PA 18951, Tel: 800-486-3575, Email: sperry@xdd-llc.com
Denis McGrath, Nobis Engineering Inc., 18 Chenell Dr., Concord, NH 03301, Tel: 603-224-4182, Fax: 603-224-2507, Email: dmcgrath@nobisengineering.com

Pilot and full scale ISCO tests were carried out at the former Eastland Woolen Mill, Corinna, ME in prior years as part of an overall program to reduce the residual contamination left after a large excavation and thermal treatment project was completed.  Approximately 100,000 tons of soil were excavated and treated thermally to reduce the average concentration of tri-, di, and chlorobenzene to below 15 mg/kg prior to backfilling.  Residual contamination existed in untreated soils on site adjacent to former USTs and a loading dock as well as the upper burden soils between the excavated materials and a state highway.  A portion of the upper burden was treated in Phase II pilot and full scale tests after determining the most effective oxidant to use at this site. The residual contamination at the USTs and former loading dock were treated in a Phase I ISCO project.  Residual contamination in the lower till burden and shallow weathered bedrock was subsequently addressed with catalyzed persulfate injection in Phase III.  A unique aspect of this project was the bath tub shape which lies between the subsurface below an existing road way down to the upper bedrock and the face of the former excavation, now backfilled with the thermally treated soils.  The lower soil and upper bedrock first had to be dewatered to allow the chemicals to be drawn into and flooding the shallow bedrock prior to completing the ISCO in the soils above.  The results of this Phase III ISCO project are described in this presentation to potentially complete the ISCO remediation of chlorobenzenes at this site.  Additional aspects of this ISCO project discuss the presence of chloromethanes and, as expected, acetone, etc. oxidation byproducts, and the determination of residual contaminant concentrations and/or rebound.  Further ISCO work extending the Phase II and III projects is currently being considered and a fourth phase may be investigated if funding becomes available for the untreated, contaminated bedrock zones below.

Chemical Oxidation of Sulfa Drugs, Barbiturates and Chlorinated Solvents in Groundwater: A Bench Test Evaluation

Neal D. Durant, Geosyntec Consultants, 10015 Old Columbia Road, Suite A-200, Columbia, MD 21046, Tel: 410-381-4333, Fax: 410-381-4499
Leah MacKinnon, Geosyntec Consultants, 130 Research Lane, Guelph, Ontario N1G 5G3, Canada, Tel: 519-822-2230, Fax: 519-822-3151
Evan E. Cox, Geosyntec Consultants, 130 Research Lane, Guelph, Ontario N1G 5G3, Canada, Tel: 519-822-2230, Fax: 519-822-3151
Sandra Dworatzek, SIREM Laboratory, 130 Research Lane, Guelph, Ontario N1G 5G3, Canada, Tel: 866-251-1747, Fax: 519-822-3151
Torben H. Jørgensen, COWI Consulting Engineers and Planners, Odensevej 95, DK-5260 Odense S, Denmark, Tel: +45 6311 4953, Fax: +45 6311 4949

The Kærgård Plantage pharmaceutical waste disposal site represents one of the most complex remediation challenges in Denmark. The site groundwater is impacted with high concentrations of relatively rare contaminants, including sulfonamides, barbiturates, and aniline, as well as chlorinated solvents and fuel hydrocarbons. Fenton’s reagent (hydrogen peroxide + Fe2+), advanced oxidation processes (AOP [hydrogen peroxide + ozone]), and permanganate are three chemical oxidation technologies that may offer promise – to varying degrees - for remediation at Kærgård. Published literature suggests that sulfonamides and barbiturates can be at least partially treated by Fenton’s reagent, AOP, and permanganate; however, there is no published literature regarding the performance of these technologies for several of the primary sulfa drugs and barbiturates at the site. Bench tests were performed using soil and/or groundwater collected from the site to evaluate the treatment performance of Fenton’s reagent, AOP, and permanganate. Treatment was assessed through monitoring a variety of parameters, including changes in contaminant concentrations, detection of degradation intermediates, and groundwater toxicity (Microtox® bioassay) consequent to treatment. A subset of tests evaluated treatment and dissolution of chlorinated solvent dense-nonaqueous phase liquids (DNAPLs) in core material from the Site. The tests demonstrated that all the primary organic contaminants in Kærgård groundwater can be effectively treated by Fenton’s reagent and AOP. A 10-fold and 3-fold reduction in groundwater toxicity was achieved by the permanganate and Fenton’s reagent treatments, respectively. Permanganate effectively treated sulfonamides and aniline as well, but achieved only partial degradation of most barbiturates. Both Fenton’s reagent and permanganate effectively accelerated dissolution and treatment of DNAPLs. Collectively, the results of these tests demonstrate that certain chemical oxidation technologies are effective for treating the unique mixture of sulfa drugs, barbiturates and chlorinated solvents at the site.

Site Remediation of Chlorinated Solvent Contaminated Groundwater via In Situ Application of Activated Persulfate

Shawn Tollin, FMC Corporation, 1735 Market St., Philadelphia, PA 19103, Tel: 215-299-6554, Email: shawn_tollin@fmc.com
Philip Block, FMC Corporation, 1735 Market St., Philadelphia, PA 19103, Tel: 215-299-6645, Email: philip_block@fmc.com
Marguerite Carpenter, FMC Corporation, 1735 Market St., Philadelphia, PA  19103, Tel: 215-299-6210, Email: marguerite_carpenter@fmc.com
John Haselow, Redox Tech, 200 Quade Dr, Cary, NC 27513, Tel:  919-678-0140, Email: haselow@redox-tech.com

Activated Persulfate was utilized for the in situ chemical oxidation (ISCO) of a chlorinated solvent impacted site. The ISCO application reduced groundwater concentrations of the contaminants.  Activated persulfate is a strong chemical oxidant that is capable of destroying a wide range of chemical contaminants, including chlorinated solvents.   For this application, alkaline activation of the persulfate was accomplished through co-injection of sodium hydroxide. The site is a former industrial property located in the South San Francisco Bay area.  Contaminants migrated from the primary site to an adjacent property that is under-going a property transaction.  As a result, a rapid approach to site remediation is desired.  Volatile Organic Compound (VOC) impacts were observed in groundwater from depths of 15 to 28 feet below ground surface (ft bgs).  The site lithology at these depths is predominantly Bay Mud – silty clay formation.  The remediation is driven by vinyl chloride.   In late 2006, solutions of persulfate and sodium hydroxide were injected via hydraulic fracturing in 91 direct-push wells on approximately 15-foot centers due to the tight clay formation.  A total of 150,000 lbs of persulfate were injected along with enough sodium hydroxide to reach a target pH of 11.  Continuous electrical conductivity profile measurements were utilized to demonstrate the delivery of persulfate to the target zones. Post-injection sampling indicates a significant reduction in VOCs across the site.  A second round of activated persulfate injection is planned for early 2007.  

Treatment of Non-Aqueous Phase Liquids (NAPLs) using Surfactant-Enhanced In-Situ Oxidation (S-ISCO^®)

George E. Hoag, Ph.D., VeruTEK Technologies, Inc., 628-2 Hebron Avenue, Suite 505, Glastonbury, CT  06033, Tel:  860-633-4900, Fax:  860-633-6501, Email: ghoag@VeruTEK.com
John Collins, Ph.D., VeruTEK Technologies, Inc., 628-2 Hebron Avenue, Suite 505, Glastonbury, CT  06033, Tel:  860-633-4900, Fax:  860-633-6501, Email: Jcollins@VeruTEK.com
Ken Hwang, Ph.D., VeruTEK Technologies, Inc., 165 River Rd Ste 1D, Willington, CT 06279, Tel:  860-429-5748, Fax:  860-429-5748, Email: KHuang@VeruTEK.com

Traditional ISCO methods have had limited success in degrading non-aqueous phase liquids (NAPLs) because of mass transfer limitations controlling the rate of dissolution of NAPL constituents into groundwater. In Situ Chemical Oxidation (ISCO) reactions predominantly take place in the aqueous phase in the subsurface. Treatability studies and field verification pilot-studies have been conducted to evaluate the effectiveness of a new type of Coelution Technology^®, Surfactant-Enhanced In-Situ Chemical Oxidation (S-ISCO^®), in reducing the amount of non-aqueous phase liquids (NAPLs) in soils. The S-ISCO® technology, patent-pending by VeruTEK Technologies, Inc., uses biodegradable, food-grade cosolvents and surfactants (VeruSOL^®) (for example, coconut oil, castor oil and citrus extracts) to solubilize immiscible phase organic compounds into groundwater. Application of S-ISCO with VeruSOL^® destroys contaminants in-place using traditional ISCO processes, particularly activated persulfate. S-ISCO® involves coeluting both the cosolvent-surfactant mixture with the oxidant enabling simultaneous dissolution and oxidation. Selection of the specific VeruSOL^® mixture is dependent on the nature of the NAPL components, particularly, the mol fractions and octanol-water partition coefficients (K_ow) of the individual organic compounds. The coelution involves the controlling the rate of NAPL compound dissolution and the oxidation reaction rates. Laboratory treatability studies demonstrate that the solubilization reaction by surfactant and surfactant/cosolvent mixtures resulted in significant increases in dissolved phased COCs without mobilizing NAPL. Winsor Type I solubilization was observed; Winsor Type II and Winsor Type III behaviors were not observed. Laboratory and field pilot test results for both chlorinated solvent mixtures of DNAPLs and Former Manufactured Gas Plant (DNAPLs) demonstrate that the dissolution and oxidation reactions can be beneficially controlled.

Top