APPLICATION OF PASSIVE SAMPLERS TO MONITOR REMEDIATION PROGRESS

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1 APPLICATION OF PASSIVE SAMPLERS TO MONITOR REMEDIATION PROGRESS Upal Ghosh Department of Civil & Environmental Engineering University of Maryland Baltimore County, Baltimore, MD

2 Report Documentation Page Form Approved OMB No Public reporting burden for the collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing the collection of information. Send comments regarding this burden estimate or any other aspect of this collection of information, including suggestions for reducing this burden, to Washington Headquarters Services, Directorate for Information Operations and Reports, 1215 Jefferson Davis Highway, Suite 1204, Arlington VA Respondents should be aware that notwithstanding any other provision of law, no person shall be subject to a penalty for failing to comply with a collection of information if it does not display a currently valid OMB control number. 1. REPORT DATE NOV REPORT TYPE 3. DATES COVERED to TITLE AND SUBTITLE Application of Passive Samplers to Monitor Remediation Progress 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) University of Maryland Baltimore County,Department of Civil & Environmental Engineering,5200 Westland Boulevard,Baltimore,MD, PERFORMING ORGANIZATION REPORT NUMBER 9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES) 10. SPONSOR/MONITOR S ACRONYM(S) 12. DISTRIBUTION/AVAILABILITY STATEMENT Approved for public release; distribution unlimited 11. SPONSOR/MONITOR S REPORT NUMBER(S) 13. SUPPLEMENTARY NOTES Presented at the 15th Annual Partners in Environmental Technology Technical Symposium & Workshop, 30 Nov? 2 Dec 2010, Washington, DC. Sponsored by SERDP and ESTCP. U.S. Government or Federal Rights License 14. ABSTRACT Passive samplers have been used as collection devices for measuring low concentrations of pollutants from air and water phases. Contaminant biouptake in benthic organisms and flux from contaminated sediments are controlled by the freely dissolved porewater chemical concentrations in sediment. The main challenges in measuring porewater concentrations of hydrophobic compounds such as PCBs and PAHs by direct extraction is the very low freely dissolved concentrations of these compounds and interference in the measurement from sorption to colloidal phases that are difficult to separate. Our recent work has explored the use of thin films of polyoxymethylene (POM) as equilibrium passive samplers to measure porewater concentrations of a range of toxic organic chemicals including PCBs, PAHs, dioxins, furans, and chlorinated pesticides in laboratory measurements and measurements conducted in the field. Using POM passive samplers we monitored changes in in-situ aqueous PCB concentrations over time at a pilot study site in a river where activated carbon was amended to sediment to reduce PCB bioavailability. Results of passive sampler monitoring in the field over four years indicated that amendment of activated carbon to sediments reduced porewater PCB concentration near the sediment surface to values lower than ambient concentrations in the overlying water. This finding reveals that amendment of strong sorbents may be effective in reversing the direction of chemical flux between contaminated sediment and overlying water locally during a pilot study. This talk will present an overview of the use of passive equilibrium samplers in laboratory assessment of aqueous equilibrium concentrations and use in the field to monitor changes in contaminant concentrations in the sediment porewater and overlying water.

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4 Passive Sampling Approaches for Contaminated Sediment Management Technical Session No. 4C P APPLICATION OF PASSIVE SAMPLERS TO MONITOR REMEDIATION PROGRESS DR. UPAL GHOSH University of Maryland Baltimore County 5200 Westland Boulevard Technology Research Center Room 184 Baltimore, MD (410) ughosh@umbc.edu CO-PERFORMERS: Ms. Barbara Beckingham and Mr. Piuly Paul (UMBC) assive samplers have been used as collection devices for measuring low concentrations of pollutants from air and water phases. Contaminant biouptake in benthic organisms and flux from contaminated sediments are controlled by the freely dissolved porewater chemical concentrations in sediment. The main challenges in measuring porewater concentrations of hydrophobic compounds such as PCBs and PAHs by direct extraction is the very low freely dissolved concentrations of these compounds and interference in the measurement from sorption to colloidal phases that are difficult to separate. Our recent work has explored the use of thin films of polyoxymethylene (POM) as equilibrium passive samplers to measure porewater concentrations of a range of toxic organic chemicals including PCBs, PAHs, dioxins, furans, and chlorinated pesticides in laboratory measurements and measurements conducted in the field. Using POM passive samplers we monitored changes in in-situ aqueous PCB concentrations over time at a pilot study site in a river where activated carbon was amended to sediment to reduce PCB bioavailability. Results of passive sampler monitoring in the field over four years indicated that amendment of activated carbon to sediments reduced porewater PCB concentration near the sediment surface to values lower than ambient concentrations in the overlying water. This finding reveals that amendment of strong sorbents may be effective in reversing the direction of chemical flux between contaminated sediment and overlying water locally during a pilot study. This talk will present an overview of the use of passive equilibrium samplers in laboratory assessment of aqueous equilibrium concentrations and use in the field to monitor changes in contaminant concentrations in the sediment porewater and overlying water. C-94

5 Conceptual model for PCB flux Hunters Point example Grasse River example 2 ng/l ng/l sediment water PCB flux PCB flux sediment water 37 ng/l ng/l Aqueous concentration Aqueous concentration

6 PCB UPTAKE PATHWAYS TO FISH 1 2 X X 1: bioaccumulation in benthic organisms and ingestion by fish 2: flux into water column and uptake through the pelagic food chain 3

7 Partitioning of hydrophobic chemicals in sediment 1)Hydrophobic chemicals partition among the aqueous and different solid phases 2)Equilibrium distribution can be described by linear free energy relationships POM Freely dissolved C total = C free + C DOC + C POC C total = C free + DOC*K DOC *C free + POC*K POC *C free DOC POC Two approaches to measure total and freely dissolved concentrations: 1)Remove POC by centrifugation/flocculation, measure total dissolved concentration and DOC, and estimate freely dissolved concentration. 2)Use calibrated passive sampler to estimate freely dissolved concentration, measure DOC, and estimate total dissolved concentration.

8 Passive sampler calibration Equilibrium passive samplers : measure freely dissolved aqueous concentration by partitioning C aq = K POM * C POM Determine K POM for suite of target analytes using equilibrium batch tests with POM in sediment-water slurry or in spiked water Performance reference compounds (PRCs) or other methods may be used to account for non-equilibrium conditions during field exposures Example POM calibration for PCB congeners

9 PCB uptake kinetics in 76 mm POM sheets in sediment slurry 120% % '<t co >. 10 "C -10 CJ c: 0 CJ... 0 ~ 0 80% 60% 40% 20%,( ', ,4'-dichlorobiphenyl --&- 0 A 6 2,4', 6-trichlorobiphenyl 2,2',4,5'-tetrachlorobiphenyl 2, 2', 3', 4, 5-pentachlorobiphenyl 2,2',4,4',5,5'-hexachlorobiphenyl 2,2',3,4',5,5',6-heptachlorobiphenyl 2,2',3,3',4,5,6,6'-octachlorobiphenyl 0% exposure days Hawthorne et al., Anal. Chem. 2009, 81,

10 Applications of passive sampling: 1) Batch equilibrium measurements for low aqueous concentrations (PCBs, PAHs, dioxins) 2) In-situ probing to assess ambient contaminant concentrations or to assess changes with time or with treatment Pictures of typical applications: water sediment Laboratory batch equilibrium Stream water quality assessment Field evaluation of treatment performance Depth profiling of porewater conc. in sediment

11 Application 1: Batch equilibrium studies: 1000 control PCBs in sediment treated with GAC Conc. in lipid (μg/g) Tetra PCB congeners in L. variegatus and porewater for three freshwater sediments before and after treatment with AC Concentration in water (ng/l) (Sun & Ghosh, ES&T 2008)

12 Estimating from sediment concentration 1.E+04 1.E+03 :! 0')1.E () <: 0 u -o a_1 E+01 ::i -o 2 (tl. 1.E+OO (/1 UJ 1.E-01 1.E-02 1.E-02 1E-01 1.E+OO 1.E+01 1.E+02 1E+03 1.E+04 Measured Lipid Cone [ug/g] Werner et al. EST 2010

13 Estimating from equilibrium aqueous concentration 1.E+04 1.E+03 (d) '6i1.E+02 a, 2. 0 s:: 8 1.E+01 :!:!.9:-...J -g 1 E+OO... ttl E ti w 1.E-01 1.E-02 1 E E-03 1.E-02 + *~ ++ -:\= + 1.E-01 1.E+OO 1.E+01 1.E+02 1.E+03 1.E+04 Measured Lipid Conc[ug/g] Werner et al. EST 2010

14 Application 1: Dioxins and furans bioaccumulation in earthworms from soil a. BSAF values of dioxins in soil SW-20 b. BSAF values of furans in soil SW No treatment % AC 5% AC (Fagervold et al., ES&T 2010) 2378-TCDD PCDD HCDD HCDD HCDD H7CDD OCDD 2378-TCDF PCDF PCDF HCDF HCDF HCDF HCDF H7CDF H7CDF OCDF BSAF BSAF 0.05 c c. BSAF values of dioxins in soil SW d. BSAF values of furans in soil SW TCDD PCDD HCDD HCDD HCDD H7CDD OCDD 2378-TCDF PCDF PCDF HCDF HCDF HCDF HCDF H7CDF H7CDF OCDF BSAF BSAF

15 Application 1: Dioxins and furans bioaccumulation in earthworms from soil 1.4 a. SW-20 dioxins in porewater 140 b. SW-20 furans in porewater (Note: different concentration scale compared to furans) SW-20 NT SW-20 2% SW-20 5% SW-20 NT SW-20 2% SW-20 5% Aqueous concentration (pg/l) (Fagervold et al., ES&T 2010) 2378-TCDD PCDD HCDD HCDD HCDD H7CDD OCDD 2378-TCDF PCDF PCDF HCDF HCDF HCDF HCDF H7CDF H7CDF OCDF Aqueous concentration (pg/l) c. SW-265 dioxins in porewater SW-265 NT SW-265 2% SW-265 5% d. SW-265 furans in porewater SW-265 NT SW-265 2% SW-265 5% Aqueous concentration (pg/l) 2378-TCDD PCDD HCDD HCDD HCDD H7CDD OCDD 2378-TCDF PCDF PCDF HCDF HCDF HCDF HCDF H7CDF H7CDF OCDF Aqueous concentration (pg/l)

16 Application 1: Batch equilibrium studies with POM: Dioxins and furans in soil Earthworm and equilibrium aqueous phase concentration in 2 soils before and after treatment with AC (Fagervold et al., ES&T 2010)

17 Application 2: In-situ monitoring after sediment remediation Pilot-scale field applications of activated carbon to reduce PCB bioavailability in contaminated sediments Grasse River, NY Hunters Point, CA

18 PILOT DEMONSTRATION IN GRASSE RIVER (Participants: Alcoa, EPA, UMBC, Stanford University, Anchor Env., Brennan, Tetra Tech, Arcadis-BB&L, QEA) L-shaped silt screen to minimize suspended particle transport Mixed Tiller (75 x 100 ) Unmixed (50 x 50 ) Tine Sled (50 x 60 ) Initial testing area (50 x 100 ) Equipment mobilized on barges Target dose of activated carbon = 0.5x TOC in surficial sediments (+50% safety factor) No measurable change in water-column PCBs downstream Post-treatment monitoring for 3 years

19 Grasse River: In-situ monitoring studies Grasse River, NY In-river baseline deployment of field exposure cages with L. variegatus using a method adapted from Burton et al Parallel deployment of POM passive samplers L. variegatus

20 % REDUCTION IN WATER VS. AC DOSE > 99% reduction for all treatment sites in 2009 for AC dose >4% 17

21 PCB IN WATER BASED ON IN-SITU PASSIVE SAMPLERS Reduced aqueous PCB on sediment surface at AC treated sites compared to overlying water 18

22 Future research needs Better understanding of the diffusion process of PCBs, PAHs, dioxins through polymers Standardized (consensus) polymers that everyone can obtain and use easily Standardized calibration of polymers for a range of contaminants (PAHs, PCBs, dioxins, furans, pesticides) Better understanding of uptake kinetics in different exposure modes (water column vs in sediment)

23 Acknowledgments Funding support from SERDP/ESTCP programs, USEPA GLNPO, and Alcoa Graduate students & post docs: Barbara Beckingham, Xueli Sun, Piuly Paul, Bo Wang, Sonja Fagervold