Tracking Full-Scale Performance of an Injectable Sorptive Biobarrier: One Year and Beyond
0 likes160 views
The document details the full-scale performance of an injectable sorptive biobarrier tested at a former gas station in Daly City, California, focusing on the remediation of contaminated groundwater. It highlights the historical context of prior remedial efforts, the chemical analysis used in monitoring, and the effectiveness of biostimulation techniques, such as Plumestop® and ORC-A® injections. Monitoring results indicate significant reductions in MTBE and TBA concentrations, with ongoing evaluations planned to ensure microbiological robustness and distribution efficacy.
Tracking Full-Scale Performance of an Injectable Sorptive Biobarrier: One Year and Beyond
- 1. Tracking Full-Scale Performance of an Injectable Sorptive Biobarrier: One Year and Beyond The logo and ANTEA are registration trademarks of Antea USA, Inc.
- 2. The Site Bench/Pilot Testing Full-Scale Application
- 3. From the Sky: 76 Station Daly City California
- 4. The History • Operating gas station with prior leaking UST • Prior remedial efforts to clean up BTEX and TPH-GRO successful using AS/SVE • Minimal impacts remain on-site. Off-site groundwater is the current focus (<10 lbs. of MTBE mass in groundwater) • Groundwater table at 32 ft. bgs • San Mateo County Groundwater Protection Program oversees the site
- 5. The History (continued) • MNA important polishing on-site • Site responded well to increased dissolved oxygen • Plume migration through narrow channels of sand and limited to a 5 ft. vertical horizon – 32 ft. – 37 ft. bgs • Expansion of AS/SVE or switch to P&T for off-site riddled with logistical issues and costly
- 6. Site Geology 6 ~12 ft. to 37-38 ft. bgs: Poorly sorted primarily sand (SP) with some interbedded silt and clay 38 ft. to 45 ft. bgs: Continuous clay layer (aquitard) found in all borings south of most downgradient wells
- 7. Groundwater Flow Direction Groundwater Elevation Contours (A Zone) September 17, 2018
- 8. Molecular Biological Tools and Geochemistry
- 10. • MW-8, 10, 11, and 14 used for microcosm testing • Water column height dictated specific approach per well • Sulfate and ORC-A® addition allowed comparison to unamended control • PM-1 organism (MTBE degrader) and MTBE/TBA gene functions analyzed • 13C labeled MTBE used to show microbial growth versus actual degradation Microbial Results
- 11. The Site Full-Scale ApplicationBench/Pilot Testing
- 12. The Chemistry 12
- 13. The Chemistry 1. Fine particle activated carbon (1-2 microns) 2. Combined with unique polymer for distribution enhancement 3. Binds to aquifer solids. Establishes biodegradation site 4. Regeneration occurs
- 14. Bench Test Results 14 Baseline 1 Baseline 2 Control 1 Control 2 Treated 1 Treated 2 Analyte (µg/L) 3/10/16 3/10/16 3/31/16 3/31/16 3/31/16 3/31/16 1,2 Dichloroethane 41 34 34 34 < 5.0 < 5.0 MTBE 6,400 6,200 6,800 7,100 530 590 tert-Amyl methyl ether 48 50 62 60 < 5.0 < 5.0 tert-Butanol < 10000 < 10000 580 540 < 100 < 100 Total VOCs 6,489 6,284 7,476 7,734 530 590 Average Total VOCs 6,386.5 7,605 560 % Removed (comp. Control) --- --- 93% Groundwater sample collected from MW-14 Two doses of PlumeStop® tested Calcium salts added to drop out amendment prior to extraction and analysis Experiment designed for no volatilization
- 16. • Direct push PlumeStop® at MW-14 and MW-24 (locations exceeded goal) • Direct push ORC-A® to enhance biodegradation 30 days later • Three injection points per well per amendment • Monitor every two weeks for MTBE/TBA and secondary parameters – geochem/field parameters/microbial (RNA vs DNA) • Remedial goal – 1 mg/L MTBE Pilot Test Approach
- 18. The Results: MW-14 50 100 150 200 250 300 1,000 2,000 3,000 4,000 5,000 6,000 7,000 8,000 8/14/13 3/2/14 9/18/14 4/6/15 10/23/15 5/10/16 11/26/16 6/14/17 12/31/17 Concentration(TBAug/L) Concentration(MTBE,µg/L) MTBE, TBA, versus Time Former 76 Service Station 11202 Daly City, California MTBE (ug/L) Plume Stop Injection ORC-A Injection Plume Stop Injection TBA (ug/L) 9.43 µg/L
- 19. The Results: MW-24 0 1000 2000 3000 4000 5000 6000 7000 0 2000 4000 6000 8000 10000 12000 14000 16000 18000 20000 4/30/16 8/8/16 11/16/16 2/24/17 6/4/17 9/12/17 12/21/17 Concentration(TBA,ug/L) Concentration(MTBE,µg/L) MTBE, TBA versus Time Former 76 Service Station 11202 Daly City, California MTBE (ug/L) Plume Stop Injection ORC-A Injection TBA (ug/L) 114 µg/L
- 20. Secondary Results: MW-14 -150 -100 -50 0 50 100 150 0 0.5 1 1.5 2 2.5 3 3.5 4 1/31/16 3/21/16 5/10/16 6/29/16 8/18/16 10/7/16 11/26/16 1/15/17 ORP,mV Concentration(DO,mg/L) DO, ORP, versus Time Former 76 Service Station 11202 Daly City, California Oxygen, Dissolved (mg/L) Plume Stop Injection ORC-A Injection
- 21. Secondary Results: MW-24 -250 -200 -150 -100 -50 0 50 100 150 200 250 0 0.5 1 1.5 2 2.5 3 3.5 4 1/31/16 5/10/16 8/18/16 11/26/16 3/6/17 6/14/17 9/22/17 12/31/17 4/10/18 OxidationReductionPotential(mV) Concentration(ug/L) DO, ORP versus Time Former 76 Service Station 11202 Daly City, California Oxygen, Dissolved… Plume Stop Injection
- 22. Lessons Learned • Direct push injection into sand is not always what it appears • A bioamendment can be an important addition to the carbon-based amendment, but natural conditions can still support biodegradation • With the right microbiology and conditions, substantial reduction in MTBE/TBA concentrations is possible • 5 points per day is reasonable production rate
- 23. The Site Full-Scale ApplicationBench/Pilot Testing
- 24. • Four biobarriers installed to protect downgradient municipal well approximately 600 ft. away • X lbs. of PlumeStop® per direct push point, X lbs. of PlumeStop® per injection well • Six performance monitoring wells MW-14, 21, 24, 26, 27 and 28 will be monitored quarterly. 50% reductions at MW21 and MW-28 at 30 days Full Scale Biobarrier Application
- 25. Injection Layout 12 injection wells 32 direct push injection locations
- 26. Injection Challenges: Night work Major roadway requires lane closure Infrastructure Sands that compact
- 27. Photos from the field 27
- 28. 1 10 100 1,000 10,000 100,000 4/1/12 12/22/12 9/13/13 6/5/14 2/25/15 11/17/15 8/8/16 4/30/17 1/20/18 10/12/18 Concentration(MTBE,µg/L) MTBE and TBA versus Time 76 (Former BP) Service Station 11202 Daly City, California MTBE (ug/L) TBA (ug/L) PlumeStop Injection (Pilot) ORC-A Injection (Pilot) PlumeStop Injection MW-14
- 29. 1 10 100 1,000 10,000 100,000 4/30/16 8/8/16 11/16/16 2/24/17 6/4/17 9/12/17 12/21/17 3/31/18 7/9/18 10/17/18 Concentration(µg/L) MTBE and TBA versus Time 76 (Former BP) Service Station 11202 Daly City, California MTBE (ug/L) TBA (ug/L) PlumeStop Injection (Pilot) ORC-A Injection (Pilot) PlumeStop Injection MW-24
- 30. 1 10 100 1,000 10,000 100,000 7/15/15 1/31/16 8/18/16 3/6/17 9/22/17 4/10/18 10/27/18 Concentration(µg/L) MTBE and TBA versus Time 76 (Former BP) Service Station No 11202 Daly City, California MTBE (ug/L) TBA (ug/L) PlumeStop Injections MW-21
- 31. 1 10 100 1,000 10,000 100,000 4/25/17 8/3/17 11/11/17 2/19/18 5/30/18 9/7/18 Concentration(µg/L) MTBE and TBA versus Time 76 (Former BP) Service Station No 11202 Daly City, California MTBE (ug/L) TBA (ug/L) PlumeStop Injections MW-28
- 32. 2019 Data MTBE – January 2019 ND ND ND 21 ND 1,500 2,000 140 87 750 2,400 890 570 180 570 4.7 27 ND ND ND ND ND MTBE – September 2018
- 33. Future Considerations Will the microbiology remain robust Was distribution sufficient at all injection locations Will we have to inject an electron acceptor
- 34. Acknowledgements: Dacre Bush, PG (Antea Group Long Beach) Craig Sandefur and Dan Nunez (Regenesis) Gregg Drilling Microbial Insights
- 35. We do more than effectively solve client challenges; we deliver sustainable results for a better future. Thank you If you have more questions… Jack Sheldon Antea Group Senior Professional