Surfactant Flushing 2009 Pilot Study Fueling Point – Military Site Northeastern USA Jeffrey H. Harwell Asahi Glass Chair of Chemical Engineering The University of Oklahoma Principal Surbec Environmental, LLC

Background Jet fuel spill discovered in 2006 Jet fuel spill discovered in 2006 Probably happened in 2001 Probably happened in 2001 Depth to water 44 ft Depth to water 44 ft Sandy aquifer - 20% silt Sandy aquifer - 20% silt Drinking water wells within ¼ mile but in deeper aquifer Drinking water wells within ¼ mile but in deeper aquifer Estimated 350,000 to 700,000 gal spill Estimated 350,000 to 700,000 gal spill

Pilot Study Objectives Surfactant Enhanced Aquifer Remediation (SEAR ) Evaluate effectiveness and efficiency Demonstrate chemical/hydraulic control Generate design for full-scale implementation

Within the LNAPL plume generally up-gradient minimize recontamination No impact to existing soil vapor extraction system Pilot Study Location

Treatability Study Surfactant system design Surfactant system design Provide proof of concept Provide proof of concept Geochemistry considerations Geochemistry considerations Heterogeneity issues Heterogeneity issues Optimization of injection strategy Optimization of injection strategy

Step 1: Formulate Microemulsion Monomer Organic Contaminant Micelle Increasing Salinity IIIIII

Vials Surf. A (wt%) Surf. B (wt%) Salt A (wt%) Salt B (wt%) Middle Phase Aqueous Phase NAPL Phase Winsor Type BA NoHazyYellowI BA YesClearYellowIII BA YesClearYellowIII BA YesClearYellowIII BA YesClearYellowIII BA YesClearYellowIII BA YesClearYellowIII BA YesClearYellowIII BA YesClearYellowIII BA YesClearYellowIII BA YesClearYellowIII BA YesClear Hazy Yellow III BA NoHazyYellowI BA YesClearYellowIII BA YesClearYellowIII BA YesClearYellowIII BA YesClearYellowIII Table 1 Microemulsion Phase Behavior Step 1: Formulate Microemulsion Mixture of food grade anionic surfactants

Table 2 Sorption Studies Step 2: Verify Adsorption Losses are Reasonable Very sandy soil; very low adsorption

Sample [Surf. A] [Surf. B] [Salt A][Salt B] [Calcium Chloride] Presence of Precipitate Presence of Separation IDwt% ppmYes/No P NoYes* P NoYes* P NoYes P NoYes P NoYes Table 3 Precipitation and Phase Separation Tests Note: * No phase separation within the first day of observation Step 3: Examine Sensitivity to Phase Separation

Solution Polymerμ (Average) (ppm)(cp) NAPL Surfactant/Polymer (S/P) Solution , Surfactant/Polymer/Alkaline (S/P/A) Solution , Table 4 Viscosity of Different Solutions Note:  (average) is the average viscosity shown in the unit of centipoise (cp) Step 4: Mobility Ratio

Column Test #Description% RecoveryNote 1Surfactant only99.49Observed some surfactant retardation 22PV Surfactant/Polymer99.93 Mobilization started on the second PV of surfactant injection 32PV Surfactant/Polymer/Alkaline99.94 Mobilization started on the second PV of surfactant injection 4 0.2PV P/A, 1PV S/P/A, 0.2PV P/A at 1500 ppm polymer* More mobilized NAPL in the first PV of mobilization 5 0.2PV P/A, 1PV S/P, 0.2PV P/A at 500 ppm polymer More solubilization observed when compared to column test # PV P/A, 1PV S/P/A, 0.2PV P/A at 500 ppm polymer More mobilization observed when compared to column test # PV P/A, 1PV S/P, 0.05 PV P/A at 500 ppm polymer When compared to column 8, less amount of NAPL mobilized and more solubilized NAPL PV P/A, 1PV S/P/A, 0.05 PV P/A at 500 ppm polymer 99.93** The NAPL was mobilized out from the column 3-5 minutes before column test #7 and there was a higher amount of NAPL mobilized out from column when compared to column test # PV P/A, 1PV S/P, 0.2 PV P/A at 100 ppm polymer 94.6 Less amount of mobilized oil when compared to 500 ppm polymer PV P/A, 1PV S/P/A, 0.05 PV P/A at 100 ppm polymer Less amount of mobilized oil when compared to 500 ppm polymer 111 PV S/A, no polymer92.97 Solubilization mechanism is dominant Table 5 Summary of 1-D Column Tests *S: surfactant, P: polymer, A: alkaline; PV = pore volume **yellow highlighted: the optimal surfactant candidate based on the performance of NAPL recovery and the recovery mechanism (mainly mobilization) Step 5: Optimize Injection Sequence

Pilot Study Overview Footprint was < 1/8 acre; well spacing of 25 ft. 2 pore volumes of surfactant at 0.94 wt % 2 nine-spot patterns Submersible pumps recover NAPL/water/surfactant Process equipment oil/water separator injection mixing tanks/pumps injection/extraction manifolds influent/effluent pumps carbon vessels

Mixing & Holding Tanks, O/W Separator, GAC Canisters

Site Map

Timeline Pre-Flush – 1 pore volume – 31 Aug 09 – 6 Sep 09 – Set BioTraps on 3 Sep 09 – Tracer (NaBr) injected 4 – 5 Sep 09 Surfactant Flush – 2 pore volumes – 6 – 21 Sep 09 – Groundwater sampled on 10 and 17 Sep 09 – Surfactant first observed – EX-02 and OWS on 20 Sep 09 – EX-01 on 23 Sep 09

Timeline Post Flush - 5 pore volumes – 21 Sep 09 – 1 Nov 09 – Applied vacuum on extraction wells on 25 Sep 09 – Reconfigured injection/extraction on 20 Oct 09 – Groundwater sampled on 1 Oct 09 and 2 Nov 09 – BioTraps 7 Oct 09 – Injected remaining treated water 3 – 6 Nov 09 to empty tanks

Size: 18,000 Gallons Transfer Pump Mixing Tanks

Size: 18,000 Gallons Mixer with propeller

Injection Manifold

Flow Meter Flow Control Unit Flow Meters and Flow Controllers

Remediation and Monitoring Wells

Oil/Water Separator 45 min. Residence Time

Surfactant Concentrate 330 Gallon Totes

Added Manually to Mixing Tank

Phase Behavior Test 2.5 min 3 min NaCl: % with 0.1% increment Quality Control Check

Phase Behavior Test 1 hour NaCl: % with 0.1% increment

Data Assessment Pre-Pilot Conditions – API Model estimated 2,300 gal LNAPL Results – Total LNAPL Recovery was 2,740 gal – API Model estimated140 gal remained

LNAPL Thickness/Distribution

API Model

Soil Sampling Results - Upper

Soil Sampling Results - Middle

Soil Sampling Results - Lower

LNAPL Recovery

Extraction Well - Partial Plugging

Key Findings Motivation for full-scale implementation – Significant LNAPL removal - 2,740 gal – Significant reduction in LNAPL thickness – Significant reduction in soil TPH-DRO – Hydraulic control achieved and maintained – No increase in dissolved-phase concentrations – Optimized surfactant formulation

Key Findings Lessons learned as a result of the pilot study – Heterogeneous NAPL thickness along perimeter – Heterogeneous stratigraphy – Mobilization of fine sand – Emulsification within process equipment Fixes – Better placement of well screens – Improved well locations – Improved surfactant formulation – Longer residence times in oil/water separator

Full Scale Implementation Final review with State Regulatory Agency, Military Base Groups on November 12 th Final review with State Regulatory Agency, Military Base Groups on November 12 th Decision for full scale (3.6 acres) made - RFP issued Decision for full scale (3.6 acres) made - RFP issued Implementing in 3 parcels of 1.2 acres each Implementing in 3 parcels of 1.2 acres each System installation in May 2010 System installation in May 2010 Surfactant injection in June 2010 Surfactant injection in June 2010 Post surfactant flush to be finished November 2010 Post surfactant flush to be finished November 2010