Incremental Sampling Methodology

Advancing the Practice

In Massachusetts

Jay Clausen: U.S. ACE, ERDC/CRREL

Nancy Bettinger: MassDEP/ORS

This Presentation

Nancy Bettinger

Overview of ISM

Planning ISM Projects in Massachusetts

Jay Clausen

Soil Sampling Issues

Decision Unit Examples

Overview of ISM

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.

Representative Sampling

Confident Decisions

Incremental Sampling Methodology Technical and Regulatory Guidance

~

Forerunners

Dr. Pierre M. Gy

Gy Sampling Theory

Charles Ramsey, Envirostat

Multi-Increment Sampling (MIS)

1993 1998 1992 1979

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

ISM Decision Units

50’ Perimeter DUs

How does ISM work?

ISM Field Sampling

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.

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

Why is representative sampling difficult?

Concentration

Median

Mean

Soil Heterogeneity

Long-Scale Across a site

Short-Scale Within a few feet

Micro-Scale Within a sample

5 4

1

2 7

6 3

41,400

416

136

42,800 27,700

1,220

286

Source: EPA Munitions Response Initiative Training, 2008, Presentation by Thomas Jenkins

Abandoned Industrial Site, Nevada

TNT (mg/kg)

Planning an ISM Project In Massachusetts

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

What do you

mean you’re

not comfortable

with ISM?

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

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

Working with the Laboratory

Source: ITRC ISM Part 2 IBT Training Presentation - Draft

Specific laboratory procedures are a necessary component of ISM.

Particle Size Segregation

The small particles always fall to the bottom!

Highest Concentrations Are Associated with the Smallest Particles

Correct Sub-Sampling in the Laboratory is Critical!

Laboratory Accreditation for ISM

National Environmental Laboratory Accreditation Program

Non-NELAP State Accreditation

Agency-specific Accreditation

DoD Environmental Laboratory Approval Program

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”

Resist the Temptation!

References and Resources

ASTM (ASTM International). 2003. Standard Guide for Laboratory Subsampling of Media Related to Waste Management Activities. Method D 6323-98.

Gerlach, R W, and J M Nocerino. 2003. Guidance for Obtaining Representative Laboratory Analytical Subsamples from Particulate Laboratory Samples. EPA/600/R-03/027.

Gy, Pierre M. 1979. Sampling of Particulate Materials: Theory and Practice, Volume 4. Elsevier Scientific Publishing Company, 1979.

Gy, Pierre M. 1992. Sampling of Heterogeneous and Dynamic Material Systems: Theories of Heterogeneity, Sampling and Homogenizing. Elsevier Scientific Publishers, 1992.

Gy, Pierre M. 1999. Sampling for Analytical Purposes. John Wiley & Sons Ltd. 1998, reprinted in 1999.

ITRC. 2012. 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. 1993

USACE. 2008. Incremental Sampling: MIS-Based Laboratory Requirements for the Analysis of Explosives (Method 8330B) and Metals in Solid Matrices.

USACE. 2009. Implementation of Incremental Sampling (IS) of Soil for the Military Munitions Response Program. Interim Guidance Document (IGD) 09-02. Environmental and Munitions Center of Expertise.

USEPA. 1999. Correct Sampling Using the Theories of Pierre Gy. Office of Research and Development Technology Support Project.

USEPA. 2006. Method 8330B: Nitroaromatics, Nitramines, Nitrate Esters by High-Performance Liquid Chromatography.

Walsh, M. R. 2009. User’s Manual for the CRREL Multi-Increment Sampling Tool. ERDC/ CRREL SR-09-1.