Cosolvent Flushing and Enhanced Bioremediation at a Dry Cleaner Site

Transcription

1 Cosolvent Flushing and Enhanced Bioremediation at a Dry Cleaner Site By Michael D. Annable Department of Environmental Engineering Sciences 1 1

2 Project Team University of Florida Mike Annable, James Jawitz, Mike Brooks Suresh Rao, Irene Poyer (Purdue) USEPA-NRMRL-SPRD-Ada Guy W. Sewell, Lynn Wood, Susan Mravik Frank Beck, Ken Jewell, Tony Lee, Steve Acree, Randal Ross LFR Levine-Fricke Kevin Warner Randy Sillan MSU James M. Tiedje, Shannon Flynn 2 Project Funding State of Florida, EPA-TIO, Florida Center for Soild and Hazardous Waste Management, SERDP (FIBRC-WES) 2

3 Brief Cosolvent Flushing History 3 Before 1980 Cosolvents theory - Pharmaceuticals Mid 1980s Cosolvents used to study transport of hydrophobic compounds in soils Early 1990s Cosolvents investigated for remediation 1995 First Cosolvent Flood at Hill AFB (Florida) 1996 Second Cosolvent Flood at Hill AFB (Clemson) 1998 Cosolvent Flood at a Dry Cleaner Site (LFR, Sages) 1999 Cosolvent Flood at Dover AFB nd Cosolvent Flood at Dover AFB (Clemson) Full-Scale Flood at Sages (Others?) 3

4 Sages Dry Cleaner Site Jacksonville, Florida 4 4

5 Pilot test at Jacksonville, FL (Sages): Dry Cleaner PCE source zone 8 to 9.5 m below ground surface 7 m long by 3 m wide Performanced based cores and tracers 5 5

6 Sages Site 3 Injection Wells (IWs) 6 Recovery Wells (RWs) 7 Multi-Level Samplers (MLSs) RW003 RW004 Northing (ft) RW002 MLS-2 IW001 MLS-3 IW002 MLS-1 MLS-7 MLS-4 MLS-6 IW003 MLS-5 RW005 6 RW007 RW Easting (ft) 6

7 26 27 High Frequency Soil Sampling at Sages IW RW Depth BGS (ft) mg PCE/L MeCl Depth BGS (ft) mg PCE/L MeCl Thin lenses of DNAPL on minor permeability contrasts 7 7

8 Sages Well Layout Recovery wells Injection wells 8 8

9 Sages Site Partitioning Tracer Test: S N = 0.26 % V PCE 50 L methanol RW MLS-4 Red S N = 1.0 % C/C ethyl-1-hexanol Volume (kl) Time (d) 9

10 Sages Site Cosolvent Flushing Flowrate (gpm) Packer Height (ft) 95 % consumable grade ethanol Time (days) 0 10

11 RW002 PCE Cosolvent Flushing ethanol PCE (mg/l) Ethanol (%) Volume (kl) RW003 PCE PCE (mg/l) ethanol Volume (kl) Ethanol (%) Total PCE Removed 67.4 kg 41.5 L 11

12 Sages Site Waste Treatment: Air Stripping Macro Porous Polymer (MPP) 12 Trailer-mounted MPP system PCE recovered from effluent 12

13 Summary Results Cosolvent Extraction: 43 L PCE Removed (Mass Recovery) ~63 % PCE Removed (Partitioning Tracer) 65% Removal based on Soil Core Data 13 13

14 Concentration (or Flux) Reduction in the Source Zone Average Conc. of PCE (mg/l) 60 Average = 49 mg/l Average = 26 mg/l Post-Remediation Time (Years) 14 Mass Reduction = 64% : Flux Reduction = 47% n = 35 sampling locations 14

15 15 Solvent Extraction Residual Biotreatment (source management) Remove more accessible fraction of DNAPL, lower dissolved concentrations/flux. Reduce time/distance needed to meet GW quality objectives. Activate reductive bio-transformations in high redox environments. Insure supply of e- donor, accelerate process and reduce uncertainty. Meet regulatory requirements. 15

16 Pre-Cosolvent Flush Site Characterization Aerobic Conditions Low levels of daughter products (TCE) DNAPL contamination identified at 26 to 31 ft. bgs 16 16

17 Cosolvent Extraction Injection Well Ethanol Flush 90%+ Mass Removal Recovery Well GW Flow 17 17

18 Residual Contaminants Restoration?, Risk Reduction? PCE Ethanol Mixed GW Flow 18 18

19 Bioremediation FNA, Dissolution < Assimilative Capacity Bioactive Zone GW Flow 19 19

20 Sage s Dry Cleaner Site Jacksonville, Florida MW-513C3 MLS C2 C1 MW-511 MW-508 RW-002 RW-003 RW-007 RW-006 RW-004 RW-005 DNAPL AREA 20 0 ft. 20 ft. 40 ft. 60 ft. 80 ft. 20

21 DNAPL AREA DNAPL AREA DNAPL AREA DNAPL AREA ug/l MW3 PCE Pre-Ethanol Flush (with Day 29 data) MW3 80,000 µg/l = 480 µm ~1 Month Post-Flush ug/l ug/l ug/l MW-513 C3/15 C2/14 C1/16/17/18 MW-511 MW-508 C10/19 C7/20 MW1 MW-513 C3/15 C2/14 C1/16/17/18 MW-511 MW-508 C10/19 C7/20 MW ug/l C5/11 MW2 C5/11 MW ug/l MW3 ~2.5 Months Post-Flush MW3 ~4 Months Post-Flush ug/l C7/20 C7/20 C3/15 MW1 C3/15 MW ug/l 0 ug/l MW-513 C2/14 C1/16/17/18 MW-511 MW-508 C10/19 MW-513 C2/14 C1/16/17/18 MW-511 MW-508 C10/19 21 C5/11 C5/11 MW2 MW2 21

22 DNAPL AREA DNAPL AREA DNAPL AREA ~25 Months Post-Flush PCE ~28 Months Post-Flush ug/l MW3 MW ug/l C7/20 C7/20 C3/15 MW1 C3/15 MW ug/l ug/l MW-513 C2/14 C1/16/17/18 MW-511 MW-508 C10/19 MW-513 C2/14 C1/16/17/18 MW-511 MW-508 C10/ ug/l ug/l C5/11 MW2 ~31 Months Post-Flush C5/11 MW2 MW ug/l C7/ ug/l 0 ug/l MW-513 C3/15 C2/14 C1/16/17/18 MW-511 MW-508 C10/19 MW1 22 C5/11 MW2 22

23 DNAPL AREA DNAPL AREA DNAPL AREA DNAPL AREA cis-dce 16,000 µg/l = 165 µm Pre-Ethanol Flush (with Day 29 data) ~1 Month Post-Flush ug/l MW3 MW ug/l ug/l ug/l MW-513 C3/15 C2/14 C1/16/17/18 MW-511 MW-508 C10/19 C7/20 MW1 MW-513 C3/15 C2/14 C1/16/17/18 MW-511 MW-508 C10/19 C7/20 MW ug/l C5/11 MW2 ~2.5 Months Post-Flush C5/11 MW2 ~4 Months Post-Flush 6000 ug/l MW3 MW ug/l 2000 ug/l MW-513 C3/15 C2/14 C1/16/17/18 MW-511 MW-508 C10/19 C7/20 MW1 MW-513 C3/15 C2/14 C1/16/17/18 MW-511 MW-508 C10/19 C7/20 MW1 0 ug/l 23 C5/11 MW2 C5/11 MW2 23

24 DNAPL AREA DNAPL AREA DNAPL AREA cis-dce ~25 Months Post-Flush ~28 Months Post-Flush ug/l MW3 MW ug/l C3/15 C7/20 MW1 C3/15 C7/20 MW ug/l ug/l MW-513 C2/14 C1/16/17/18 MW-511 MW-508 C10/19 MW-513 C2/14 C1/16/17/18 MW-511 MW-508 C10/ ug/l C5/11 MW2 ~31 Months Post-Flush C5/11 MW ug/l MW ug/l 2000 ug/l 0 ug/l MW-513 C3/15 C2/14 C1/16/17/18 MW-511 MW-508 C10/19 C7/20 MW1 Next look at flux across a multilevel sampler transect 24 C5/11 MW2 24

25 Total Plume Mass Load Mass Load (g/day) PCE TCE c-dce Post-Remediation Time (years) 25

26 Molar Based Total Load Molar Mass Load (mmoles/day) PCE TCE c-dce Total Post-Remediation Time (years) 26 Increased mass flux caused by enhanced dissolution? 26

27 SUMMARY Solvent Extraction: 43 L PCE Removed (Mass Recovery) ~64 % PCE Removed Source Zone Flux 47% reduction in PCE concentration in the source zone multilevel sampler network PCE Daughter Product Formation Significant increase in cis-dce mass 27 For additional indications of Biological Activity See the Sages Poster 27

28 What s Next? Full Scale Remediation at Sages (early 2003) Monitoring Mass Flux from the Source Zone and in the Plume? 28 28