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1 Protocols for Use of Five Passive Samplers ITRC Protocols for Use of Five Passive Samplers to Sample for a Variety of Contaminants in Groundwater (DSP-5,

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2 1 Protocols for Use of Five Passive Samplers ITRC Protocols for Use of Five Passive Samplers to Sample for a Variety of Contaminants in Groundwater (DSP-5, 2007) Welcome – Thanks for joining us. ITRC’s Internet-based Training Program Sponsored by: Interstate Technology and Regulatory Council (www.itrcweb.org) Hosted by: US EPA Clean Up Information Network (www.cluin.org)

3 2 Housekeeping  Course time is 2¼ hours  Phone line participants Do NOT put this call on hold *6 to mute; #6 to unmute  Question & Answer breaks Phone - unmute #6 to ask question out loud Simulcast - ? icon at top to type in a question  Turn off any pop-up blockers  Move through slides Arrow icons at top of screen List of slides on left  Feedback form available from last slide – please complete before leaving  This event is being recorded  Archives accessed for free http://cluin.org/live/archive/ Go to slide 1 Move back 1 slide Download slides as PPT or PDF Move forward 1 slide Go to seminar homepage Submit comment or question Report technical problems Go to last slide

4 3 ITRC Disclaimer and Copyright Although the information in this ITRC training is believed to be reliable and accurate, the training and all material set forth within are provided without warranties of any kind, either express or implied, including but not limited to warranties of the accuracy, currency, or completeness of information contained in the training or the suitability of the information contained in the training for any particular purpose. ITRC recommends consulting applicable standards, laws, regulations, suppliers of materials, and material safety data sheets for information concerning safety and health risks and precautions and compliance with then-applicable laws and regulations. ECOS, ERIS, and ITRC shall not be liable for any direct, indirect, incidental, special, consequential, or punitive damages arising out of the use of any information, apparatus, method, or process discussed in ITRC training, including claims for damages arising out of any conflict between this the training and any laws, regulations, and/or ordinances. ECOS, ERIS, and ITRC do not endorse or recommend the use of, nor do they attempt to determine the merits of, any specific technology or technology provider through ITRC training or publication of guidance documents or any other ITRC document. Copyright 2010 Interstate Technology & Regulatory Council, 444 North Capitol Street, NW, Suite 445, Washington, DC 20001

5 4 ITRC (www.itrcweb.org) – Shaping the Future of Regulatory Acceptance  Host organization  Network State regulators  All 50 states, PR, DC Federal partners ITRC Industry Affiliates Program Academia Community stakeholders  Wide variety of topics Technologies Approaches Contaminants Sites  Products Technical and regulatory guidance documents Internet-based and classroom training DOEDODEPA

6 5 ITRC Course Topics Planned for 2010 – More information at www.itrcweb.org  Decision Framework for Applying Attenuation Processes to Metals and Radionuclides  LNAPL Part 3: Evaluating LNAPL Remedial Technologies for Achieving Project Goals  Mining Waste  Remediation Risk Management: An Approach to Effective Remedial Decisions and More Protective Cleanups  Decontamination and Decommissioning of Radiologically-Contaminated Facilities  Enhanced Attenuation of Chlorinated Organics  In Situ Bioremediation of Chlorinated Ethene - DNAPL Source Zones  LNAPL Part 1: An Improved Understanding of LNAPL Behavior in the Subsurface  LNAPL Part 2: LNAPL Characterization and Recoverability  Perchlorate Remediation Technologies  Performance-based Environmental Management  Phytotechnologies  Protocol for Use of Five Passive Samplers  Quality Consideration for Munitions Response  Determination/Application of Risk-Based Values  Use of Risk Assessment in Management of Contaminated Sites New in 2010Popular courses from 2009 ITRC 2-day Classroom Training: Vapor Intrusion Pathway

7 6 Meet the ITRC Instructors Kimberly McEvoy New Jersey Department of Environmental Protection Trenton, New Jersey 609-530-8705 Kim.McEvoy@dep.state.nj.us Hugh Rieck US Army Corps of Engineers Omaha, Nebraska 402-697-2660 Hugh.J.Rieck@usace.army.mil Louise Parker U.S. Army Engineer Research and Development Center Hanover, New Hampshire 603-646-4393 Louise.V.Parker@usace.army.mil

8 7 What you will learn…  What is passive sampling?  What passive samplers offer Quantitative data Cost savings (40-70%)  How passive samplers reflect aquifer conditions  Technical and regulatory guidance  Acceptance of passive sampling  Classes and types of passive samplers

9 8 Passive Sampler Team  Diffusion Sampler Team formed in 2000  Initial goal Develop guidance on polyethylene diffusion bags (PDBs) for collection of volatile organic compounds (VOCs) in groundwater  1st passive sampling device - diffusion type sampler (DSP-3)  Limited in analyte capabilities  Increased interest and development of passive devices  Transition to “Passive Sampler Team” What technologies are being developed and what they can do? Disseminate guidance on passive sampling technologies Be premier resource on the use of passive sampling technologies Promote adoption of regulatory guidance (i.e., acceptance)

10 9 What Does a Purge Sample Represent?  Active transport of water induced either by pumping or hand-purging  Often draws water from above and below as well as adjacent to the screened interval/open borehole  Flow-weighted average Based on indicator parameter stabilization or evacuation of the sampling system (i.e., volume purge) Gas exchange and mixing  May elevate turbidity Mobilization of colloids and sediment Mobilization of normally immobile NAPL microglobules  Compliance with drinking water standards

11 10 What Does a Passive Sample Represent?  No active transport of water induced by pumping or purging  Samples are collected from a specific depth  Rely on sampling device and well water being in ambient equilibrium with the formation water during deployment period  Reduce disturbance to the well and aquifer typically caused by bailing or over-pumping  Reduce turbidity Represent “natural conditions”

12 11 Advantages of Passive Samplers  Highly reproducible data  Provides low turbidity samples  Disposable/dedicated - no decontamination between wells  Decrease costs Field labor   Rapid field deployment and collection  Leave in quarterly Little or no disposal cost (no purge-water)  Samples discrete intervals Vertical contaminant profiling Monitor zone of highest contaminant influx  Easy to use – minimal equipment needs  No depth limit  “Green” sampling method

13 12 Limitations of Passive Samplers  May have volume/analyte limitations  Contaminant stratification requires consideration before deploying  Well must restabilize before sample collection

14 13 Passive Sampler Team Publications  User’s Guide for Polyethylene-Based Passive Diffusion Bag Samplers to Obtain VOC Concentrations in Wells (March 2001, DSP-1) Jointly developed with USGS Basic principles for deployment  Technical and Regulatory Guidance for Using Polyethylene Diffusion Bag Samplers to Monitor VOCs in Groundwater (February 2004, DSP-3) Easy to use for groundwater and surface water Quantify savings (40-70%)  Technology Overview of Passive Sampler Technologies (March 2006, DSP-4) Main application was groundwater sampling Summarized 12 passive sampling technologies  ITRC Protocols for Use of Five Passive Samplers to Sample for a Variety of Contaminants in Groundwater (February 2007, DSP-5 ) Details on “mature” passive sampling technologies from Overview Document (DSP-4) http://www.itrcweb.org/teamresources_1.asp

15 14 Classes of Passive Samplers  Diffusion Samplers: analytes reach and maintain equilibrium via diffusion through membrane Regenerated-Cellulose Dialysis Membrane (Dialysis) Sampler Rigid Porous Polyethylene (RPP) Sampler  Equilibrated Grab Samplers: collect a whole-water sample instantaneously Snap Sampler™ HydraSleeve™ Sampler  Accumulation Sampler: rely on diffusion and sorption to accumulate analytes in sampler GORE™ Module

16 15 Ambient Flow Through a Well  Relies on flow through in the well screen Screened zone is in active exchange with formation water  Water above screen may be “stagnant”  References ASTM, 2002 Powell R.M., and R.W. Puls, 1993 Robin, M.J.L. and R.W. Gillham, 1987

17 16 General Deployment  Device suitable for analytes of interest  Sample volume i.e., QA/QC and duplicates Appendix A: Minimum Volumes  Deployment period Device and site specific  Well restabilization  Sampler equilibration  Deployment depth Should not be arbitrary  Depends on well or site specific data quality objectives (DQOs) Sampler represents a depth interval

18 17 Contaminant Stratification  Stratification is well-specific  Majority of wells are not stratified  Contaminant stratification in an aquifer vs. in the well

19 18 Contaminant Stratification (continued) No stratification 0 Total BTEX Concentration (mg/L) 160 400 8001200 140 150 170 Water Table 180 PDB Samples Purge Sample Stratification in a well Depth (feet) Toluene (µg/L) 0204060 Depth (feet below top of casing) 15 20 25 30 35 40 45 50 PDB samples Low-flow sample

20 19 Contaminant Distribution  Multiple samplers deployed through screened or open interval Can represent contaminant concentrations over water column  Vertical flow profiling, depending data quality objectives (DQOs), determines primary input/exit of groundwater flow Borehole flowmeter Interval packer/pump tests  Profiling techniques can aid in Refining site conceptual model Remedial process optimization (RPO)  Profiling techniques Target a specific depth interval Can monitor interval with highest concentration  Conservative approach for long-term monitoring

21 20 Data Quality Objectives (DQOs)  Prior to implementation, all parties should agree on DQOs  For instance Vertical contaminant distribution may be a DQO so multiple samplers deployed in a well may be advised (vertical profiling) Long-term monitoring projects, a single sampler may be appropriate for the DQO  Is your sampling method meeting the DQOs?  Do all parties agree?

22 21 Data Quality Objectives (DQOs) (continued)  DQOs define Sampling goal Target analytes Hydrologic concerns  Pumping methods Draw groundwater into the well screen from an undefined area Example: 3-volume purge and low flow  Passive methods Sample depth-specific intervals in well Groundwater moves through the well screen under ambient flow conditions Pumping moves water toward intake from the induced flow field in proportion to hydraulic conductivity Pump Intake Every groundwater sampling technique characterizes contamination differently!

23 22 Regulatory Perspective  No regulatory or statutory prohibitions to using passives samplers  “De facto” acceptance of passive samplers in 50 states and worldwide  New Jersey Department of Environmental Protection guidance on polyethylene diffusion bags (PDBs) (2005)  Regulatory agencies use ITRC Polyethylene Diffusion Bag (PDB) guidance for state guidance Passive samplers have been used Does your state have any Statutes, Regulations, or Guidance that prohibit or impede the use of passive sampling technologies for the collection of groundwater samples? (16 state responses: Appendix B)

24 23 In Summary  Passive samples collect analytes that come in contact with the sampler under ambient flow  Value of passive samplers Inexpensive Broad analyte capabilities Reduced sampler error  Assist in site characterization identifying Stratification Target zones for remediation Migration pathways  1:1 correlation may not occur Discrete concentration vs. flow weighted concentration May reflect nature of sampling method  i.e., dilution during purging, pumping versus passive

25 24 Questions and Answers Covered so far  Introduction to passive (no- purge) sampling  Advantages/limitations  General considerations when using passive samplers  Regulatory perspectives Now  Questions and answers Next – technical aspects for five passive samplers  Diffusion Samplers: analytes reach and maintain equilibrium via diffusion through membrane 1. Regenerated-Cellulose Dialysis Membrane (Dialysis) Sampler 2. Rigid Porous Polyethylene (RPP) Sampler  Equilibrated Grab Samplers: collect a whole-water sample instantaneously 3. Snap Sampler™ 4. HydraSleeve™ Sampler  Accumulation Sampler: rely on diffusion and sorption to accumulate analytes in sampler 5. GORE™ Module

26 25  Diffusion Samplers: analytes reach and maintain equilibrium via diffusion through membrane 1. Regenerated-Cellulose Dialysis Membrane (Dialysis) Sampler 2. Rigid Porous Polyethylene (RPP) Sampler  Equilibrated Grab Samplers: collect a whole-water sample instantaneously 3. Snap Sampler™ 4. HydraSleeve™ Sampler  Accumulation Sampler: rely on diffusion and sorption to accumulate analytes in sampler 5. GORE™ Module Diffusion Samplers

27 26 Diffusion Sampler Basics

28 27 Diffusion Sampler Advantages  Groundwater sampling time in the field is decreased – no pumping needed  Eliminates purge water and disposal costs  Excludes turbidity from groundwater samples – no filtering needed  Disposable – no cleaning or cross-contamination Regenerated Cellulose Dialysis Membrane (Dialysis) Rigid Porous Polyethylene (RPP)

29 28 Regenerated-Cellulose Dialysis Membrane Sampler Basics  Referred to as the “Dialysis Sampler”  Regenerated-cellulose dialysis membrane Filled with deionized water Hydrophilic membrane  Currently must be constructed  Membrane sizes 2.5-inch diameter for 4-inch wells 1.25-inch diameter for 2-inch wells  Sample volumes 2.5-inch x 2 ft long contains 2 liters 1.25-inch x 2 ft long contains 500 mls  Pore size is 18 Angstroms  Developed by U.S. Geological Survey (USGS) Fully assembled Dialysis sampler ready for deployment

30 29 Dialysis Equilibration Times  Determined in laboratory in bench-scale tests  95% or greater equilibrium reached in dialysis samplers within 1-7 days for most cations and trace metals 1-3 days for all VOCs on 8260B list (including MTBE) 1-3 days for anions, silica, DOC, CH4, sulfide 7-14 days for explosives compounds 28 days or more for Hg, Ag, Sn

31 30 Dialysis Sampler Advantages  Collects inorganic and organic chemical constituents  Quick equilibration and deployment times – generally 1-2 weeks  Relatively inexpensive to construct  Excludes turbidity from groundwater samples – no filtering needed  Sample volume can be up to 2 L

32 31 Dialysis Sampler Limitations  Must construct sampler from raw materials  Samplers must be kept wet between construction and deployment  Membrane can biodegrade within 4-6 weeks Not a problem for shorter deployments Can maintain integrity for longer periods in very cold water  Samplers lose water volume slowly (<3% per week) Not a problem for short deployments Internal support for high ionic strength waters is available

33 32 Ethylbenzene (µg/L) 0.1 10 1000 0.1 101000 LRL 1/2 MDL Vinyl Chloride (µg/L) 0.001 0.1 10 1000 0.0010.1101000 LRL 1/2 MDL Dialysis Field Comparison Results Dialysis Sampler Low-Flow Purging Chloride (mg/L) 0.1 10 1000 0.1 10 1000 LRL 1/2 MDL Manganese (µg/L) 0.1 10 1000 0.1101000 LRL 1/2 MDL From: Imbrigiotta et al. (2007)

34 33 Dialysis Field Comparison Results (Dialysis Samplers vs Purging Methods)  Parameters with favorable results VOCs Cations and anions Most trace metals Explosive compounds Others (silica, ethene, CO 2, CH 4, TDS, SC, DOC)  Parameters with questionable results p-Isopropyltoluene n-Butylbenzene s-Butylbenzene Nickel Sulfide See Table 5-3 in ITRC Protocols Document (DSP-5)

35 34 Dialysis Sampler Summary  Collects both organic and inorganic chemical constituents  Do not require filtration of samples  Equilibrate within 1-2 weeks for most constituents  Deployment times 1-2 weeks in most wells  Dialysis samplers recover comparable concentrations of VOCs vs. PDB samplers VOCs and most inorganics vs. low-flow and purging and sampling  Dialysis samplers should not be used when Sampling for mercury, silver, or tin Equilibration will take longer than 4 weeks Total concentrations are needed  Dialysis samplers should be used with caution when Sampling for nickel and sulfide

36 35 Rigid Porous Polyethylene (RPP) Samplers  Made of rigid, porous polyethylene  Pore sizes 6-15 microns  5 inches long  1.5 inches in diameter  Filled with deionized water  Standard size holds 90-100 mL In protective mesh ready for deployment and packaged in disposable water-filled sleeve for shipping Cap Delrin plug

37 36 Select RPP Analytes and Equilibration Times Analyte Equilibration time (days) Dissolved gases14 Perchlorate, chloride, hexavalent chromium, nitrate, sulfate, soluble iron 14 Methane, ethane, ethene (MEE)14 Water soluble VOAs (i.e. MTBE, MEK, Acetone, 1,4-Dioxane) 14 Water soluble SVOCs (i.e. NDMA, phenols)14 Dissolved metals (priority pollutant list)21 (all except silver and copper) Explosives (i.e. HMX, TNB, RDX and TNT)21

38 37 RPP Advantages  Can be used to collect most inorganic and limited organic analytes  Are commercially available and field-ready  Can be stacked when additional volume needed  Excludes particles larger than the pore space of the sampler

39 38 RPP Limitations  Must be stored and shipped fully immersed in deionized water  Have not been tested for all analytes  Multiple samplers are needed to obtain sufficient volume for multiple Analyte types and/or QA/QC  Requires advanced analytical techniques to analyze for SVOCs  Equilibrium times for less water soluble VOCs and SVOCs are not currently known

40 39 McClellan AFB Multi-analyte, Multi-sampler Study (Parsons 2005) Low-Flow Purge Sample Concentration (µg/L) RPPs Sample Concentration (µg/L) Metals: 1,4-Dioxane: Anions: Hex Cr: VOCs: For All Data y = 0.941x R 2 = 0.9764

41 40 RPP Representative Field Study for 1,4-Dioxane at a North Carolina Site Each point on the plot represents a single- constituent data pair of each sampling method. R 2 = 0.9224 y = 0.852x n = 9 RPP (mg/L) Low Flow (mg/L)

42 41 RPP Representative Field Study for 1,4-Dioxane at a North Carolina Site RPP (mg/L) Low Flow (mg/L) R 2 = 0.999 y=1.073x n=10 Each point on the plot represents a single- constituent data pair of each sampling method.

43 42 RPP Summary  Can be used to sample for Most inorganics Water soluble VOCs and SVOCs  It’s not currently known if they can be used for water-insoluble VOCs and SVOCs  Can be used in deep wells  Can be used in conjunction with PDBs  Disposable sampler No decontamination required

44 43 Diffusion Sampler Summary  RPP and Dialysis Membrane samplers can be used for VOCs, SVOCs, metals, anions, and cations  Minimum deployment time for RPP and Dialysis sampler is ~2 weeks  Compare well with conventional methods  Collect samples at a discrete interval in well screen  RPP sampler can be used for quarterly or longer deployments  Major limitation of RPP sampler is sample volume  Major limitation of Dialysis sampler is that it undergoes biodegradation Regenerated Cellulose Dialysis Membrane Rigid Porous Polyethylene (RPP)

45 44  Diffusion Samplers: analytes reach and maintain equilibrium via diffusion through membrane 1. Regenerated-Cellulose Dialysis Membrane (Dialysis) Sampler 2. Rigid Porous Polyethylene (RPP) Sampler  Equilibrated Grab Samplers: collect a whole-water sample instantaneously 3. Snap Sampler™ 4. HydraSleeve™ Sampler  Accumulation Sampler: rely on diffusion and sorption to accumulate analytes in sampler 5. GORE™ Module Equilibrated Grab Samplers

46 45 Equilibrated Grab Samplers  Collects sample from discrete interval in well screen  Collect “whole water” samples that can be tested for any analyte  Collects samples in “real time”  Equilibration period allows Well to recover from sampler placement Materials to equilibrate with analytes in well water  Technologies Snap Sampler™ HydraSleeve™ Sampler Snap Sampler™ HydraSleeve™ Sampler

47 46 Snap Sampler TM Components  Sampler body with trigger mechanism  Bottles Have two openings & spring-activated caps 40-mL VOA glass vials  Fits in 2-inch wells 125-mL HDPE bottles  Fits in 2-inch wells 350-mL HDPE bottles  Fits in 4-inch wells  Trigger line Mechanical Electronic Pneumatic  Docking station 125 mL 40 mL

48 47 Snap Sampler TM – Collecting a Sample  Sample bottles deployed & remain in open position  Equilibration period Minimum of 1 to 2 weeks Can be used for quarterly, semi-annual, or annual sampling  Pull handle on trigger line to close bottle (i.e., collect sample)  Samples sealed in situ  No sample transfer required at the surface

49 48 Snap Sampler TM Advantages  No analyte restrictions  Reduced sampling variability Minimal agitation of well during sampling  Collect samples with ambient turbidity Bottles remain sealed under in-situ conditions No sample transfer  No exposure to weather, surface contamination, etc.  Some studies have shown better recovery of volatiles and gases

50 49 Snap Sampler TM Limitations  Sample Volume Multiple bottles are needed to obtain volume for multiple analyte types and/or QA/QC  Trigger lines are fixed length and thus cannot be readily moved to other wells

51 50 Snap Sampler TM – VOC Field Study  Very good correlations  Slightly higher concentration values with Snap Sampler TM than low-flow 0.1 1 10 100 1000 Low Flow VOC (ug/L) Snap Sampler VOC (ug/L) 10000 0.1110100100010000

52 51 Snap Sampler TM – Multi-analyte Field Study Study at former McClellan Air Force Base (Parsons Inc. 2005) Low-Flow Purge Sample Concentration (µg/L) Snap Sampler™ Concentration (µg/L) Anions 1,4 Dioxane R 2 = 0.99 for all analyte comparisons to low flow 0.010.1110100100010000 100000 100000 10000 1000 100 10 1 0.1 0.01 VOCs

53 52 Snap Sampler™ Summary  Sample all analyte types  Volume limited for long analyte list  Samples are sealed at the point of collection  No transfer of sample required  Data correlates well with standard sampling methods

54 53 HydraSleeve™ Components Discharge tube Sampler sleeve Reusable sampler weight Reed valve

55 54 HydraSleeve™ Sample Collection Empty Full Sample Interval Filling

56 55 HydraSleeve™ Advantages  Fits in most diameter wells  Can sample all types of analytes  Sample Volume 2-inch HS collects 650 mL to 1 L 4-inch HS collects 1250 mL to 2 L  Easy to use with minimal training  Can sample Very deep wells Crooked wells  Can collect low turbidity samples

57 56 HydraSleeve™ Limitations  Sample Volume Custom samplers can be fabricated in a wider diameter and/or longer length to maximize sample volume for longer analyte lists Work with lab regarding minimum sample volume  Using table in Appendix A of the ITRC Protocol Document, DSP-5

58 57 HydraSleeve™ – Field Study (1 of 2) Concentration (ppb) 2-inch diameter well in Northern California (Geomatrix Inc., 2000) HydraSleeve™ Purge/Sample

59 58 HydraSleeve™ – Field Study (2 of 2)  Comprehensive comparison of Low-flow and 3-well volume purged samples Samples collected using 6 no-purge samplers  Analytes included VOCs, 1,4 dioxane, anions, metals, and hexavalent chromium  Study Findings “The HydraSleeve and Snap Sampler TM produced results most similar to the higher concentrations obtained by low- flow and 3-well volume purging and sampling methods” “Appears to be a technically viable method for monitoring all of the compounds in the demonstration” Former McClellan Air Force Base (Parsons Inc., 2005)

60 59 HydraSleeve™ Sampler Summary  Sample all analyte types  Sample volumes up to 2 L  Can be used in Deep wells Crooked wells  Comparable results to conventional pumped methods  Can be left in well for quarterly, semi-annual, or annual sampling  Disposable sampler No decontamination required

61 60 Equilibrated Grab Samplers Summary  Samples can be analyzed for all analyte types Providing there is adequate sample volume  Collect whole water samples in real-time  Can be used for quarterly, semi-annual, or annual sampling events  Use an equilibration period to reduce sampling biases  Collect samples at a discrete interval in well screen  Compare well with conventional methods Snap Sampler™ HydraSleeve™ Sampler

62 61  Diffusion Samplers: analytes reach and maintain equilibrium via diffusion through membrane 1. Regenerated-Cellulose Dialysis Membrane (Dialysis) Sampler 2. Rigid Porous Polyethylene (RPP) Sampler  Equilibrated Grab Samplers: collect a whole-water sample instantaneously 3. Snap Sampler™ 4. HydraSleeve™ Sampler  Accumulation Sampler: rely on diffusion and sorption to accumulate analytes in sampler 5. GORE™ Module Accumulation Samplers

63 62 Accumulation Samplers  Rely on diffusion and sorption  Examples of accumulation samplers Semi-permeable Membrane Devices (SPMD) Polar Organic Chemical Integrative Sampler (POCIS) Passive In-situ Concentration Extraction Sampler (PISCES) GORE™ Module  More information on other accumulation samplers is available Overview of Passive Sampler Technologies (March 2006, DSP-4) http://www.itrcweb.org/

64 63 GORE™ Module Components  GORE™ Module Section 2 in ITRC Protocol Document (DSP-5)  Attachment Line  Stainless steel weights Knot (secure to wellhead) Attachment Line Loop to attach line Tag with unique serial number Adsorbent Weight

65 64 GORE™ Module Sample Collection  Dissolved compounds partition to vapor (Henry’s Law)  Diffusion through hydrophobic, vapor-permeable membrane  Adsorption onto media  Duplicate samples Vapors pass through Liquid water remains outside Adsorbents GORE-TEX ® Membrane

66 65 GORE™ Module Analysis  No adsorbent transfer in field  Thermal desorption/GC/MS VOCs and SVOCs US EPA Method 8260/8270, modified for thermal desorption

67 66 GORE™ Module Advantages  Sample small diameter wells and multi-level systems >0.25 inches Crooked wells  No minimum sample volume limitation  No need to refrigerate samples  Minimal water disruption - ~10 mls displacement  Short sampling period - 15 minutes to 4 hours Longer-term deployment – sub ppb concentrations  US EPA ETV verified (Einfeld and Koglin, 2000) http://www.epa.gov/etv/pdfs/vrvs/01_vr_gore.pdf

68 67 GORE™ Module Limitations  Sole source supplier and laboratory analysis  Organic compounds only Compound detection limited by vapor pressure  Data reporting Measured mass (µg) Concentrations are calculated by GORE based on  Measured mass, sampling rate, time, water temperature, and water pressure –Reference Section 2.4.5 of ITRC Protocol Document (DSP-5)

69 68 GORE™ Module – VOC Field Study Military Base, Mid-Atlantic United States  Strong spatial correlation with low-flow sampling  Greater sensitivity & better plume delineation 1,1,2,2-Tetrachloroethane GORE™ Module dataLow-flow sampling data

70 69 GORE™ Module – VOC Field Study Dry Cleaner, Southeastern United States  Compared to slow purge and disposable bailer  Good correlation PCE, TCE, cis-1,2-DCE (ug/L) y = 1.1611x R 2 =0.982 N=12 0 10000 20000 30000 Concentration – GORE™ Module Concentration - Bailer C1,2-DCE TCE PCE Linear 30000 20000 10000 0

71 70 GORE™ Module Summary  Accumulation sampler Passive operation Compounds partition to vapor, then diffuse to adsorbent  Easy field deployment Small diameter wells Short sampling period  Able to detect very low analyte concentrations  Collect samples at a discrete interval in well screen  Data reported Mass measured or as concentrations (calculated)  Data comparable with conventional sampling  Can only be used for organic compounds

72 71 Overall Summary for Protocols for Use of Five Passive Samplers  Passive Samplers offer Quantitative data Cost savings  Use is dependent upon the DQOs  Tech & Reg Guidance  Acceptance  Diffusion Samplers RPP & Dialysis  Equilibrated Grab Samplers Snap Sampler™ & HydraSleeve™  Accumulation Sampler GORE™ Module

73 72 Thank You for Participating  2nd question and answer break  Links to additional resources http://www.clu-in.org/conf/itrc/passsamp/resource.cfm  Feedback form – please complete http://www.clu-in.org/conf/itrc/passsamp/feedback.cfm Need confirmation of your participation today? Fill out the feedback form and check box for confirmation email.


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