Incremental Sampling Methodology

Transcription

1 Incremental Sampling Methodology Advancing the Practice In Massachusetts Jay Clausen: U.S. ACE, ERDC/CRREL Nancy Bettinger: MassDEP/ORS

2 Nancy Bettinger This Presentation Overview of ISM Planning ISM Projects in Massachusetts Jay Clausen Soil Sampling Issues Decision Unit Examples

3 Overview of ISM

4 Incremental Sampling Methodology (ISM) is: a structured composite sampling and processing protocol having specific elements designed to reduce data variability and increase sample representativeness for a specified volume of soil under investigation.

5 Incremental Sampling Methodology Technical and Regulatory Guidance Representative Sampling ~ Confident Decisions

6 Dr. Pierre M. Gy Forerunners Gy Sampling Theory Charles Ramsey, Envirostat Multi-Increment Sampling (MIS)

7 Where and when can ISM be applied? MCP applications that call for an arithmetic mean Exposure point concentrations UCL comparisons Media Soil (primarily shallow surface soil) Sediment (future) Contaminants Energetics Metals Volatile organic compounds Semivolatile organic compounds

8 ISM Decision Units Perimeter DUs 50

9 How does ISM work?

10 ISM Field Sampling

11 Analytical variation in discrete sampling: the tip of the iceberg. Most variation in soil sampling results is due to a failure to collect a representative sample.

12 What are the sources of error in discrete sampling? Soil is highly heterogeneous. Contaminant concentrations vary widely. In a small sample, the range of concentrations are not present in in the correct proportions

13 Why is representative sampling difficult? Median Mean Concentration

14 Soil Heterogeneity Long-Scale Across a site Short-Scale Within a few feet Micro-Scale Within a sample

15 Abandoned Industrial Site, Nevada 286 TNT (mg/kg) ,400 1, , ,800 Source: EPA Munitions Response Initiative Training, 2008, Presentation by Thomas Jenkins

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17 Planning an ISM Project In Massachusetts

18 Planning an ISM Project: Assessment decisions are front-loaded. Identify the sampling objective(s) (mean?) Delineate decision units (based on the CSM) Establish the sampling plan Number of replicates Number of increments Coordinate with the laboratory before collecting samples

19 What do you mean you re not comfortable with ISM?

20 Conservative Approach Entire area of concern covered by Decision Unit(s) Decision Units < the area of each exposure point Minimum of 30 increments, 40 or 50 for moderate to highly contaminated sites Minimum of 3 ISM samples for each Decision Unit

21 Planning an ISM Project: Assessment decisions are front-loaded. Identify the sampling objective(s) (mean?) Delineate decision units (based on the CSM) Establish the sampling plan Number of increments Number of replicates Coordinate with the laboratory before collecting samples

22 Working with the Laboratory Specific laboratory procedures are a necessary component of ISM. Source: ITRC ISM Part 2 IBT Training Presentation - Draft

23 Particle Size Segregation The small particles always fall to the bottom!

24 Highest Concentrations Are Associated with the Smallest Particles

25 Correct Sub-Sampling in the Laboratory is Critical!

26 Laboratory Accreditation for ISM National Environmental Laboratory Accreditation Program Non-NELAP State Accreditation Agency-specific Accreditation DoD Environmental Laboratory Approval Program

27 Advantages of ISM More representative: Reduces the number of samples to be analyzed. More reliable: Reduces the chance of decision errors. More reproducible: Reduces the potential for costly and time-consuming do-overs

28 Resist the Temptation!

29 References and Resources ASTM (ASTM International) Standard Guide for Laboratory Subsampling of Media Related to Waste Management Activities. Method D Gerlach, R W, and J M Nocerino Guidance for Obtaining Representative Laboratory Analytical Subsamples from Particulate Laboratory Samples. EPA/600/R-03/027. Gy, Pierre M Sampling of Particulate Materials: Theory and Practice, Volume 4. Elsevier Scientific Publishing Company, Gy, Pierre M Sampling of Heterogeneous and Dynamic Material Systems: Theories of Heterogeneity, Sampling and Homogenizing. Elsevier Scientific Publishers, Gy, Pierre M Sampling for Analytical Purposes. John Wiley & Sons Ltd. 1998, reprinted in ITRC Incremental Sampling Methodology, Technical and Regulatory Guidance. Interstate Technical and Regulatory Council. Pitard, Francis F. Pierre Gy s Sampling Theory and Sampling Practice: Heterogeneity, Sampling Correctness, and Statistical Process Control, Second Ed., CRC Press USACE Incremental Sampling: MIS-Based Laboratory Requirements for the Analysis of Explosives (Method 8330B) and Metals in Solid Matrices. USACE Implementation of Incremental Sampling (IS) of Soil for the Military Munitions Response Program. Interim Guidance Document (IGD) Environmental and Munitions Center of Expertise. USEPA Correct Sampling Using the Theories of Pierre Gy. Office of Research and Development Technology Support Project. USEPA Method 8330B: Nitroaromatics, Nitramines, Nitrate Esters by High-Performance Liquid Chromatography. Walsh, M. R User s Manual for the CRREL Multi-Increment Sampling Tool. ERDC/ CRREL SR-09-1.