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Field-Based Analytical Methods for Explosive Compounds
Field-Based Analytical Methods for Explosive Compounds
Outline of Presentation
Outline of Presentation
***Safety***
***Safety***
Physical and Chemical Properties of Explosive Chemicals
Physical and Chemical Properties of Explosive Chemicals
EPA SW846 Standard Laboratory Methods for Nitroaromatic and Nitramine
EPA SW846 Standard Laboratory Methods for Nitroaromatic and Nitramine
Other Laboratory Methods
Other Laboratory Methods
Target Analytes for SW846 Methods 8330 and 8095
Target Analytes for SW846 Methods 8330 and 8095
Detection Capabilities for Soil Analysis
Detection Capabilities for Soil Analysis
Example Detection Capabilities for Water Analysis
Example Detection Capabilities for Water Analysis
Method 8330 vs
Method 8330 vs
Sampling Studies
Sampling Studies
Sampling Problem for TNT in Groundwater
Sampling Problem for TNT in Groundwater
Microbiological Transformation of TNT
Microbiological Transformation of TNT
Soil Sampling Strategy for Nature and Extent of Contamination
Soil Sampling Strategy for Nature and Extent of Contamination
Locations for Sampling Studies
Locations for Sampling Studies
Field Sampling Scheme
Field Sampling Scheme
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Monite Site, Sampling Location #1 Major Analyte: TNT (mg/kg)
Monite Site, Sampling Location #1 Major Analyte: TNT (mg/kg)
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Valcartier ATR, Sampling Location #10 Major Analyte: HMX (mg/kg)
Valcartier ATR, Sampling Location #10 Major Analyte: HMX (mg/kg)
Data Analysis from Sampling Studies
Data Analysis from Sampling Studies
Soil Analyses: On-Site & Laboratory Methods Monite Site and Hawthorne
Soil Analyses: On-Site & Laboratory Methods Monite Site and Hawthorne
Valcartier ATR: TNT Concentrations On-Site vs
Valcartier ATR: TNT Concentrations On-Site vs
Valcartier ATR: HMX Concentrations On-Site vs
Valcartier ATR: HMX Concentrations On-Site vs
Sampling Considerations for Explosives-Contaminated Sites
Sampling Considerations for Explosives-Contaminated Sites
Advantages of Using Composite Samples
Advantages of Using Composite Samples
Cost Comparisons
Cost Comparisons
Conclusions in Verse
Conclusions in Verse
Reduction of Within-Sample Heterogeneity for Soil Samples
Reduction of Within-Sample Heterogeneity for Soil Samples
Sample Processing / Holding Times
Sample Processing / Holding Times
What are the Important Target Analytes at Explosive-Contaminated Sites
What are the Important Target Analytes at Explosive-Contaminated Sites
Frequency of Occurrence of Explosives Analytes in Laboratory Analyses
Frequency of Occurrence of Explosives Analytes in Laboratory Analyses
TNT RDX
TNT RDX
Examples of Objectives for On-Site Analysis of Soils
Examples of Objectives for On-Site Analysis of Soils
Examples of Objectives for On-Site Analysis of Water
Examples of Objectives for On-Site Analysis of Water
Initial On-Site Method for TNT
Initial On-Site Method for TNT
Currently Available On-Site Technologies for Explosives
Currently Available On-Site Technologies for Explosives
EXPRAY Kit
EXPRAY Kit
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Use of EXPRAY Kit
Use of EXPRAY Kit
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EnSys Colorimetric Test Kits EPA SW846 Methods 8515 and 8510
EnSys Colorimetric Test Kits EPA SW846 Methods 8515 and 8510
Characteristics of Colorimetric Kits
Characteristics of Colorimetric Kits
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Advantages / Disadvantages of Colorimetric Methods
Advantages / Disadvantages of Colorimetric Methods
DTECH Immunoassay Test Kits EPA SW846 Methods 4050 and 4051
DTECH Immunoassay Test Kits EPA SW846 Methods 4050 and 4051
Advantages / Disadvantages of DTECH Immunoassay Methods
Advantages / Disadvantages of DTECH Immunoassay Methods
Studies Evaluating Performance of Test Kits Relative to Method 8330
Studies Evaluating Performance of Test Kits Relative to Method 8330
Environmental Technology Verification (ETV)
Environmental Technology Verification (ETV)
Fast 2000 (Research International / NRL)
Fast 2000 (Research International / NRL)
Research International / NRL Fast 2000 ETV Results (water)
Research International / NRL Fast 2000 ETV Results (water)
Advantages / Disadvantages of RI / NRL Fast 2000
Advantages / Disadvantages of RI / NRL Fast 2000
GC-Ionscan (Barringer Instruments)
GC-Ionscan (Barringer Instruments)
Barringer GC-Ionscan ETV Results (soil)
Barringer GC-Ionscan ETV Results (soil)
Barringer GC-Ionscan ETV Results (water)
Barringer GC-Ionscan ETV Results (water)
Advantages / Disadvantages of Barringer GC-Ionscan
Advantages / Disadvantages of Barringer GC-Ionscan
SRI / CRREL GC-TID Method
SRI / CRREL GC-TID Method
SRI / CRREL GC-TID ETV Results (soil)
SRI / CRREL GC-TID ETV Results (soil)
Advantages / Disadvantages of SRI / CRREL GC-TID
Advantages / Disadvantages of SRI / CRREL GC-TID
RIDASCREEN TNT Kit (Accurate Chemical & Scientific)
RIDASCREEN TNT Kit (Accurate Chemical & Scientific)
Advantages / Disadvantages of RIDASCREEN TNT Kit
Advantages / Disadvantages of RIDASCREEN TNT Kit
Action Criteria for Soils
Action Criteria for Soils
Human-Health-Related Water-Quality Criteria for Explosives-Related
Human-Health-Related Water-Quality Criteria for Explosives-Related
Detection Limits
Detection Limits
What About Other Explosives
What About Other Explosives
Overall Conclusions
Overall Conclusions
After viewing the links to additional resources, please complete our
After viewing the links to additional resources, please complete our

Презентация: «Field-Based Analytical Methods for Explosive Compounds». Автор: Susan Hardy. Файл: «Field-Based Analytical Methods for Explosive Compounds.ppt». Размер zip-архива: 1538 КБ.

Field-Based Analytical Methods for Explosive Compounds

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1 Field-Based Analytical Methods for Explosive Compounds

Field-Based Analytical Methods for Explosive Compounds

Dr. Thomas F. Jenkins Marianne E. Walsh USA Engineer Research and Development Center– Cold Regions Research and Engineering Laboratory 72 Lyme Road, Hanover NH 03755 603-646-4385 (FAX-4785) tjenkins@crrel.usace.army.mil marianne@crrel.usace.army.mil

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2 Outline of Presentation

Outline of Presentation

Important properties of nitroaromatic (TNT) and nitramine (RDX) explosives Accepted laboratory methods for explosives chemicals Detection criteria for explosives-related chemicals Why should you consider using on-site methods? Sampling considerations for explosives in soil and water Verified methods for on-site determination of explosives in soil and water Advantages / disadvantages of various on-site methods

3 ***Safety***

***Safety***

Chunks of high explosives often found at contaminated sites Concentrations of TNT or RDX in soil greater than 12% are reactive (can propagate a detonation)* Neither chunks nor soil with concentrations of TNT and RDX greater than 10% can be shipped off site using normal shipping procedures *Kristoff et al. 1987

4 Physical and Chemical Properties of Explosive Chemicals

Physical and Chemical Properties of Explosive Chemicals

Most are solids at environmental temperatures Sources often particulate at soil surface Low aqueous solubilities, slow rates of dissolution Surface contamination persists for long periods (50-100 years) Once dissolved, RDX can migrate rapidly through vadose zone TNT readily biotransforms Relatively non-volatile Thermally labile

5 EPA SW846 Standard Laboratory Methods for Nitroaromatic and Nitramine

EPA SW846 Standard Laboratory Methods for Nitroaromatic and Nitramine

Explosives in Soil and Water

Sample preparation Water: Salting-out or solid-phase extraction Soil: Ultrasonic extraction with acetonitrile Determination SW846 Method 8330 (RP-HPLC) SW846 Method 8095 (GC-ECD) (Draft)

6 Other Laboratory Methods

Other Laboratory Methods

CHPPM Method for Explosives in Water GC-ECD developed by Hable et al. 1991 Excellent method but not generally available commercially LC-MS Method (SW846 Method 8321) Available at several commercial labs Explosives not target analytes

7 Target Analytes for SW846 Methods 8330 and 8095

Target Analytes for SW846 Methods 8330 and 8095

Method 8330 8095 Nitroaromatics TNT, TNB, DNB, 2,4-DNT, 2,6-DNT, tetryl, ? ? nitrobenzene, o-,m-,and p-nitrotoluene Nitramines RDX, HMX ? ? Aminodinitrotoluenes 2-ADNT, 4-ADNT ? ? 3,5-dinitroaniline ? Nitrate esters NG, PETN ?

8 Detection Capabilities for Soil Analysis

Detection Capabilities for Soil Analysis

SW846 Method SW846 Method 8330 8095 RP-HPLC-UV GC-ECD TNT 80 µg/kg 0.45 µg/kg RDX 740 µg/kg 3.4 µg/kg HMX 1300 µg/kg 25 µg/kg NG ND 13 µg/kg

9 Example Detection Capabilities for Water Analysis

Example Detection Capabilities for Water Analysis

SW846 Method SW846 Method 8330 8095 RP-HPLC-UV GC-ECD TNT 0.1 µg/L 0.01 µg/L RDX 0.8 µg/L 0.004 µg/L HMX 1.0 µg/L 0.004 µg/L NG ND 0.2 µg/L

10 Method 8330 vs

Method 8330 vs

Method 8095

SW846 Method SW846 Method 8330 8095 RP-HPLC-UV GC-ECD more rugged in lower detection routine use capability requires less stringent simultaneous determination QA program of nitroaromatics, nitramines, and nitrate esters Most commercial labs are set up to do Method 8330 but not Method 8095. GC-ECD equipment is generally available.

11 Sampling Studies

Sampling Studies

Investigated traditional sampling approaches for explosives site characterization Surface soils Groundwater

12 Sampling Problem for TNT in Groundwater

Sampling Problem for TNT in Groundwater

First observed by Goerlitz and Franks (1989) at Hawthorne AAP Concentration of TNT increased from 2.0 to 32.0 µg/L after 60 gal of water bailed Observation confirmed by Pennington et al. (1999) at Louisiana AAP Low flow (minimal drawdown) protocol by Puls and Barcelona (1996)

13 Microbiological Transformation of TNT

Microbiological Transformation of TNT

14 Soil Sampling Strategy for Nature and Extent of Contamination

Soil Sampling Strategy for Nature and Extent of Contamination

Traditional approach uses large sampling grids, small number of discrete samples, and off-site analysis Sampling studies characterized degree of spatial heterogeneity Compared sampling error to analytical error Investigated use of composite samples to improve representativeness Compared results from on-site and laboratory analyses

15 Locations for Sampling Studies

Locations for Sampling Studies

16 Field Sampling Scheme

Field Sampling Scheme

Samples arranged in a wheel pattern Surface samples 0 cm to 15 cm

Diameter of wheel = 122 cm

Diameter of sampler = 5 cm (stainless steel auger)

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21 Monite Site, Sampling Location #1 Major Analyte: TNT (mg/kg)

Monite Site, Sampling Location #1 Major Analyte: TNT (mg/kg)

500 On-site 416 Lab

331 On-site 286 Lab

39,800 On-site 41,400 Lab

1,280 On-site 1,220 Lab

164 On-site 136 Lab

24,400 On-site 27,700 Lab

27,800 On-site 42,800 Lab

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24 Valcartier ATR, Sampling Location #10 Major Analyte: HMX (mg/kg)

Valcartier ATR, Sampling Location #10 Major Analyte: HMX (mg/kg)

16.0 On-site 15.7 Lab

54.0 On-site 75.2 Lab

100 On-site 111 Lab

324 On-site 325 Lab

183 On-site 190 Lab

321 On-site 328 Lab

111 On-site 142 Lab

25 Data Analysis from Sampling Studies

Data Analysis from Sampling Studies

Analytical error for each type estimated by: reproducibility of duplicate on-site and laboratory analyses Sampling error estimated by: differences in mean values between sampling locations Accuracy of on-site methods estimated by: comparison of mean values between on-site and laboratory analyses

26 Soil Analyses: On-Site & Laboratory Methods Monite Site and Hawthorne

Soil Analyses: On-Site & Laboratory Methods Monite Site and Hawthorne

AAP

27 Valcartier ATR: TNT Concentrations On-Site vs

Valcartier ATR: TNT Concentrations On-Site vs

Laboratory Results

28 Valcartier ATR: HMX Concentrations On-Site vs

Valcartier ATR: HMX Concentrations On-Site vs

Laboratory Results

y = 1.01x – 0.67 r = 0.990

Field (mg/kg)

HPLC (mg/kg)

2500 2000 1500 1000 500 <d

<d

29 Sampling Considerations for Explosives-Contaminated Sites

Sampling Considerations for Explosives-Contaminated Sites

Soil Concentrations in soil are spatially very heterogeneous over very short distances For discrete samples Sampling error >> Analytical error Composite samples provide more representative data than discrete samples Groundwater Concentration near well screens often not typical of formation water Low flow (minimal drawdown) sampling preferable

30 Advantages of Using Composite Samples

Advantages of Using Composite Samples

Physical averaging process Vastly improves representativeness of samples Allows a reduction in samples analyzed while improving characterization Provides a greater degree of statistical confidence than a comparable set of discrete samples Jenkins et al. 1996

31 Cost Comparisons

Cost Comparisons

TOTAL COST: $ 90 per composite sample

TOTAL COST: $ 337 per discrete sample

Collection of 7 Discrete Samples, Homogenization, Compositing, and On-Site Analysis PLUS LAB VALIDATION FOR 1 OF EVERY 10

Collection of 1 Discrete Sample, Shipment, and Lab Analysis

32 Conclusions in Verse

Conclusions in Verse

Seven sites were sampled that contained some TNT, One Ammonium Picrate, and another DNT. Very heterogeneous were these explosives as they lay, Differing by ten times ten, though two short feet away, Statistical calculations proved conclusively, did they not? That sampling error far exceeded analytical by a lot! Thus our recommendations to improve the sampling scheme Are simple and effective and are not at all extreme: Homogenize your soil cores as soon as they’re removed, Composite them together and analysis is improved. Finally, to preclude the chance of wrong interpretation, Each sample must provide us with an accurate representation. Jane G. Mason, CRREL

33 Reduction of Within-Sample Heterogeneity for Soil Samples

Reduction of Within-Sample Heterogeneity for Soil Samples

Because explosives have low volatility, thorough mixing can reduce within-sample heterogeneity Very important for split-sample analyses Use of adequate subsample size (20 g or more) Some vendors of on-site methods do not understand this problem and specify very small sample sizes More important for on-site methods where sample homogenization is less complete than in laboratory

34 Sample Processing / Holding Times

Sample Processing / Holding Times

Nitroaromatics are subject to microbiological transformation and photodegradation Soil and water samples should be kept cold in the dark Water samples can be preserved using acidification to extend holding times* Official holding times are 7 days to extraction *Jenkins et al. 1995

35 What are the Important Target Analytes at Explosive-Contaminated Sites

What are the Important Target Analytes at Explosive-Contaminated Sites

Study summarized the results from two Corps of Engineers Laboratories (1) What percentage of soil and water samples from explosives sites had explosives present? (2) When explosives were detected, what was the frequency of detecting specific analytes? Walsh et al. 1993 Walsh et al. 1993

36 Frequency of Occurrence of Explosives Analytes in Laboratory Analyses

Frequency of Occurrence of Explosives Analytes in Laboratory Analyses

Soil samples (Explosives detected: 28%) Contaminated samples TNT: 66% RDX: 27% TNT, RDX or 2,4-DNT: 94% Water samples (Explosives detected: 14%) Contaminated samples TNT: 56% RDX: 61% TNT or RDX: 94% Walsh et al. 1993

37 TNT RDX

TNT RDX

Most Important Analytes for On-Site Characterization of Explosives Contamination

38 Examples of Objectives for On-Site Analysis of Soils

Examples of Objectives for On-Site Analysis of Soils

Determining horizontal and vertical extent of contamination Allowing identification of samples for treatment studies Providing data for risk assessments Determining whether soil presents a detonation hazard Providing rapid analysis to guide excavation during remediation Determining whether treatment goals have been attained

39 Examples of Objectives for On-Site Analysis of Water

Examples of Objectives for On-Site Analysis of Water

Rapid analysis of well-water samples Evaluation of contamination in seeps and surface waters Routine assessment of treatment efficiency of pump-and-treat systems

40 Initial On-Site Method for TNT

Initial On-Site Method for TNT

Developed by Heller et al. (1982) to detect TNT in water Used colorimetric reaction and ion exchange to produce a colored stain Length of stain in tube was proportional to concentration Method was good qualitatively, but not quantitatively Was commercially available from Supelco No corresponding method for RDX

41 Currently Available On-Site Technologies for Explosives

Currently Available On-Site Technologies for Explosives

EXPRAY Kit (Plexus Scientific) EnSys Colorimetric TNT and RDX/HMX Kits (SDI) DTECH Enzyme Immunoassay Kits (SDI) Fast 2000 (Research International) GC-Ionscan (Barringer Instruments) GC-TID (SRI Instruments) SPREETA TNT Sensor (Texas Instruments)* RIDASCREEN TNT Kit (Accurate Chemical & Sci.) *Not commercially available at present

42 EXPRAY Kit

EXPRAY Kit

Simplest screening kit (Colorimetric) Useful for surfaces and unknown solids Can be used to provide qualitative test for soils Kit contains three spray cans EXPRAY 1 - Nitroaromatics (TNT) ESPRAY 2 - Nitramines (RDX) and Nitrate esters (NG) EXPRAY 3 - Black powder, ANFO Spray cans used sequentially

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44 Use of EXPRAY Kit

Use of EXPRAY Kit

For surfaces or unknown solid Wipe surface with sticky collection paper Spray paper with EXPRAY For soil Place soil on top of two filter papers Soak soil with acetone Spray the bottom filter paper with EXPRAY reagents (Spray cans used sequentially) Detection limit - 20 ng

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46 EnSys Colorimetric Test Kits EPA SW846 Methods 8515 and 8510

EnSys Colorimetric Test Kits EPA SW846 Methods 8515 and 8510

Initial TNT method developed by CRREL 1990* (8515) Initial RDX method developed by CRREL 1991** (8510) Commercialized by EnSys, now SDI Colorimetric methods for TNT and RDX / HMX Successfully used at variety of explosives sites Results correlate well with Method 8330 TNT kits cost $410 for 20 tests ($20.50 / sample) RDX kits cost $500 for 20 tests ($25 / sample) * Jenkins 1990; **Walsh and Jenkins 1991

47 Characteristics of Colorimetric Kits

Characteristics of Colorimetric Kits

TNT and RDX / HMX tests produce reddish colored solutions Concentrations are proportional to intensity of color TNT test also responds to 2,4-DNT, Tetryl, TNB RDX / HMX test also responds to NG, PETN, NC, Tetryl TNT test is subject to interference from yellow color produced from reaction with humic substances and molecular sulfur (EnSys only) RDX/HMX test is subject to interference from nitrate ion unless the optional ion exchange step is used

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50 Advantages / Disadvantages of Colorimetric Methods

Advantages / Disadvantages of Colorimetric Methods

Advantages Easy to use in the field Good quantitative agreement with laboratory results Dilutions do not require use of an additional kit Screens for presence of non-targeted explosives Successfully used at many contaminated sites Good method to assess reactivity of soil prior to shipping Disadvantages Requires some experience with chemical analysis Class specific but not analyte specific Yellow color from humics can interfere with TNT test Use for water samples requires preconcentration (SPE)

51 DTECH Immunoassay Test Kits EPA SW846 Methods 4050 and 4051

DTECH Immunoassay Test Kits EPA SW846 Methods 4050 and 4051

TNT method developed by SDI 1993* RDX method developed by SDI 1994** Immunoassay methods for TNT and RDX More selective than colorimetric, but some crossreactivity Successfully used at variety of sites Results given in concentration range; ranges in general agreement with results from Method 8330 TNT kits cost $130 for 4 tests ($32.50 / sample) RDX kits cost $130 for 4 tests ($32.50 / sample) * Hutter et al. 1993; ** Teaney and Hudak 1994

52 Advantages / Disadvantages of DTECH Immunoassay Methods

Advantages / Disadvantages of DTECH Immunoassay Methods

Advantages Configured for ease of use in the field Requires less training / experience Relatively specific for TNT and RDX Successfully used at many contaminated sites No preconcentration required for water analysis Disadvantages Fair quantitative agreement with laboratory results Provides only concentration range Provides no information on non-target analytes Dilutions require use of additional kit

53 Studies Evaluating Performance of Test Kits Relative to Method 8330

Studies Evaluating Performance of Test Kits Relative to Method 8330

Myers et al. 1994 Haas and Simmons 1995 Jenkins et al. 1996 EPA 1996 (Crockett et al.) Jenkins et al. 1997 Thorne and Myers 1997 Crockett et al. 1998 EPA 1999 (Crockett et al.)

54 Environmental Technology Verification (ETV)

Environmental Technology Verification (ETV)

Conducted by Oak Ridge NL for EPA / DoD 108 blind soil and 176 blind water samples Results compared to SW846 Method 8330 1999 Demonstration (Results on web site) Research International/NRL Fast 2000 Barringer GC-Ionscan 2000 Demonstration (Results will be on web site) SRI / CRREL GC-Thermionic Texas Instruments SPREETA

55 Fast 2000 (Research International / NRL)

Fast 2000 (Research International / NRL)

Biosensor using analyte-specific antibodies immobilized on solid support Antibodies are saturated with fluorescently labeled signal molecule creating antibody / signal complex Buffer flows over the solid support Sample injected into buffer stream If analyte present, fluorescent tag is displaced and detected by downstream fluorimeter Two separate systems for TNT and RDX Instrument cost about $23,000

56 Research International / NRL Fast 2000 ETV Results (water)

Research International / NRL Fast 2000 ETV Results (water)

TNT RDX Precision (%RSD) 76% 52% Accuracy (mean recovery) 316% 192% False positives 80% 24% False negatives 3% 3% Completeness 80% 80% Throughput 3 samples / hr / analyte

57 Advantages / Disadvantages of RI / NRL Fast 2000

Advantages / Disadvantages of RI / NRL Fast 2000

Advantages Two methods relatively specific for TNT and RDX No preconcentration required for water analysis Disadvantages Relatively poor performance in ETV trials Proven to be difficult to maintain for routine operation at Umatilla Army Depot Detection limits often inadequate for water analysis

58 GC-Ionscan (Barringer Instruments)

GC-Ionscan (Barringer Instruments)

Extensive experience in explosives detection for anti-terrorism applications (Airport Security) Uses Ion Mobility Spectrometry (IMS) Very sensitive for most explosives Combination with GC allows multianalyte method Instrument well developed; minimum development for environmental methods (water)

59 Barringer GC-Ionscan ETV Results (soil)

Barringer GC-Ionscan ETV Results (soil)

TNT RDX Precision (%RSD) 51% 54% Accuracy (mean recovery) 136% 55% False positives 25% 5% False negatives 13% 2% Completeness 100% 100% Throughput 3 samples / hr

60 Barringer GC-Ionscan ETV Results (water)

Barringer GC-Ionscan ETV Results (water)

Method tested: Detection limits (DL) inadequate for any normal application Could be combined with preconcentration using Solid Phase Extraction (SPE) to improve DL

61 Advantages / Disadvantages of Barringer GC-Ionscan

Advantages / Disadvantages of Barringer GC-Ionscan

Advantages Provides on-site multianalyte results for all major target analytes Low false positive / false negative rates Disadvantages Requires on-site chemist with experience Requires compressed gasses on site Relatively poor performance in ETV trials Instrument cost is high ($60,800) Environmental methods need further improvement

62 SRI / CRREL GC-TID Method

SRI / CRREL GC-TID Method

GC-TID Instrument manufactured by SRI (Model 8610C) Method developed by Hewitt et al. 2000 (CRREL) Allows on-site determination of important military high explosives and degradation products and some primary explosives Nitroaromatics: TNT, 2,4-DNT Nitramines: RDX, HMX Nitrate esters: PETN, NG Degradation products: TNB, 2-ADNT, 4-ADNT Instrument costs about $9000

63 SRI / CRREL GC-TID ETV Results (soil)

SRI / CRREL GC-TID ETV Results (soil)

TNT RDX Precision (%RSD) 17% 13% Accuracy (mean recovery) 97% 91% False positives 1% 0% False negatives 3% 1% Completeness 100% 100% Throughput 3 samples / hr

64 Advantages / Disadvantages of SRI / CRREL GC-TID

Advantages / Disadvantages of SRI / CRREL GC-TID

Advantages Provides on-site results for all major target analytes Excellent quantitative agreement with laboratory Low false positive / false negative rates Instrument cost only about $9,000 Disadvantages Requires on-site chemist with GC experience Requires compressed gasses on site New method; no track record at real sites

65 RIDASCREEN TNT Kit (Accurate Chemical & Scientific)

RIDASCREEN TNT Kit (Accurate Chemical & Scientific)

Classical competitive immunoassay Uses 96 well plate Antigen-antibody reaction Photometric measurement at 450 nm Requires microtiter plate spectrophotometer Detection limits: 30 ppt for water, 3 ppb for soil Crossreactive to TNB, tetryl Cost $775 for 96 test well plate

66 Advantages / Disadvantages of RIDASCREEN TNT Kit

Advantages / Disadvantages of RIDASCREEN TNT Kit

Advantages Provides a quantitative result Requires less training / experience Relatively specific for TNT No preconcentration required for water analysis Disadvantages No corresponding method for RDX No independent validation No track record at real sites

67 Action Criteria for Soils

Action Criteria for Soils

No universal criteria established Action levels are negotiated on a site-specific basis EPA Region 3 Screening Levels (Residential) TNT: 21 mg/kg RDX: 5.8 mg/kg

68 Human-Health-Related Water-Quality Criteria for Explosives-Related

Human-Health-Related Water-Quality Criteria for Explosives-Related

Chemicals

Drinking Water Health Advisory * (µg/L) TNT 2 RDX 2 HMX 400 NG 5 1,3-DNB 1 *Lifetime exposure (EPA 1996)

69 Detection Limits

Detection Limits

Soil (mg/kg) Water (?g/L) SDI EnSys (TNT, RDX) 1.0 1, 5 SDI DTECH (TNT, RDX) 0.5 5 RI Fast 2000 (TNT, RDX) -- 20 Barringer GC-Ionscan 0.3 25 (TNT, RDX) SRI / CRREL GC-TID 0.005, 0.5 -- (TNT, RDX) TI SPREETA (TNT) 0.3 -- RIDASCREEN (TNT) 0.003 --

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70 What About Other Explosives

What About Other Explosives

Ammonium picrate / picric acid Thorne and Jenkins 1997 NG and PETN EnSys (SDI) RDX test works for these too Barringer GC-Ionscan SRI / CRREL GC-TID

71 Overall Conclusions

Overall Conclusions

On-site analysis can be cost effective for site characterization at explosives-contaminated sites In combination with composite sampling, data quality can be adequate for many remedial decisions On-site analysis of production water from pump-and-treat systems has proven very cost effective A number of on-site technologies are available SW846 and ETV have provided information useful for selecting the technology for various applications

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