ism-2.itrcweb.orgISM Website

ITRC Navigating this Website 1 Introduction 1 Introduction 1.1 Sampling to Accurately Inform Environmental Cleanup 1.2 What Is ISM? 1.3 Why Should ISM Be Considered for My Site? 1.4 How Is ISM Implemented for Environmental Sampling? 1.5 Document Content – How to Use This Guidance 2 Nature of Soil Sampling 2 Nature of Soil Sampling 2.1 Introduction 2.2 ISM Accommodates the Complexities of Soil Testing 2.3 Mean ISM QC 2.4 Physical Causes of Soil Data Variability 2.5 Sample and Data Representativeness 2.6 Managing Heterogeneity to Ensure Sample Representativeness 3 Systematic Planning, Statistical Analyses, and Costs 3 Systematic Planning, Statistical Analyses, and Costs 3.1 Systematic Planning and DU Design 3.2 Statistical Concepts and Applications in ISM Projects 3.3 Planning for the Use of ISM Data 3.4 Cost-Benefit Analysis 4 Regulatory Context Field Implementation, Sample Collection, and Preparation 4 Regulatory Context Field Implementation, Sample Collection, and Preparation 4.1 Introduction 4.2 Field Planning 4.3 Field Locating 4.4 Sampling Tools and Methods 4.5 Decontamination 4.6 Sample Handling and Mass Reduction 5 Sample Processing and Analysis 5 Sample Processing and Analysis 5.1 Introduction 5.2 Choosing Appropriate ISM Processing Options 5.3 ISM Sample Preparation and Analysis 5.4 Quality Assurance/Quality Control 6 Data Quality Evaluation 6 Data Quality Evaluation 6.1 Data Verification, Validation, and Usability 6.2 Evaluation of DU Results 6.3 Evaluation of Statistical Assumptions 6.4 Decision Endpoints 7 Regulatory Acceptance 7 Regulatory Acceptance 7.1 Comparison of Survey Results from 2009 to 2019 7.2 Current State of Practice 7.3 Factors Affecting Regulatory Acceptability 7.4 Benefits to Foster Regulatory Acceptance of ISM 8 ISM for Risk Assessment 8 ISM for Risk Assessment 8.1 Introduction 8.2 Systematic Planning for ISM Data Use in Risk Assessment 8.3 EPCs from ISM Data for Human and Ecological Risk Assessment 8.4 Considerations for Use of Background ISM Data in Risk Assessment 8.5 Use of ISM for Post-Remediation Risk-Based Confirmation Sampling 8.6 Risk Communication Suggestions for Explaining ISM 9 Stakeholder Perspective and Tribal Input 9 Stakeholder Perspective and Tribal Input 9.1 Introduction 9.2 Stakeholder Engagement Through Systematic Planning 9.3 Communicating with Stakeholders 9.4 Case Studies Appendices Appendix A: Case Study Summaries Appendix B: Statistical Simulations Appendix C: Team Contacts Appendix D: Glossary Appendix E: Acronyms Appendix F: References Acknowledgments Document Feedback ITRCEnvironmental Justice/Diversity EquityInclusion ISM HOME Executive Summary: Incremental Sampling Methodology ( ISM ) is a structured composite sampling and processing protocol that reduces data variability and provides a reasonably unbiased estimate of mean contaminant concentrations in a volume of soil targeted for sampling. ISM provides representative samples of specific soil volumes defined as decision units by collecting numerous increments of soil (typically, 30 to 100 increments) that are combined, processed, and subsampled according to specific protocols. ISM is increasingly used in the environmental field to sample contaminants in soil . Proponents have found that the sampling density afforded by collecting many increments, together with the disciplined processing and subsampling of the combined increments, in most cases yields more consistent and reproducible results than those obtained by more traditional (that is, discrete) sampling approaches. Overall, members of the ISM Team have found that ISM provides reliable and reproducible sampling results and leads to less uncertainty better and more defensible decisions than have typically been achieved with many traditional sampling approaches. Such improvements result from the inherent attributes of ISM and the details of its implementation, including a clearer connection between sampling objectives and sampling approach. ISM works to address and overcome the sampling errors associated with soil sampling, integrates attention to detail in planning and field work, and requires attention to quality assurance / quality control measures throughout the sampling effort, not just in the laboratory. ISM also affords an economy of effort and resources. Generally, it would take dozens of discrete samples from any particular area to approach the reliability in an estimate of the mean provided by a well-designed incremental sampling approach. As a result of the advantages and improvements inherent in ISM over traditional methods, ISM is finding increased use in the field, as well as acceptance and endorsement by an increasing number of state and federal regulatory organizations. How to Use This Guidance This document is arranged into the following sections: Section 1 – Introduction. This updated ITRC Incremental Sampling Methodology guidance document ( ISM -2) was developed to build on the 2012 version ( ISM -1) and to reflect advancements in technology and share case studies that provide insight into the potential applications, benefits, and challenges of the approach. The ISM -2 Update Team also determined that clarification of the ISM -1 guidance was necessary. That clarification statement is now appended at the beginning of the ISM -1 document. ISM -1 continues to be a useful tool for those interested in learning the concepts of ISM . Section 2 – Nature of Soil Sampling provides the reader with an understanding of the unique challenges associated with sampling soil for the purpose of obtaining representative contaminant concentrations and how ISM is specifically designed to address these challenges. Contaminants in soil and other particulate media are often distributed unevenly at the scales of interest to decision -makers. Conventional soil sampling approaches that fail to address this heterogeneity can result in over- or underestimating contaminant concentrations, leading to decision errors. Section 2 provides the reader with a detailed understanding of why contaminants are heterogeneously distributed in soil , the consequences of that heterogeneity for soil sampling and decision -making, and how ISM is systematically designed to address this heterogeneity through the use of replicates of multiple increments. This section also discusses how data variability caused by soil heterogeneity is measured, as well as provides a simplified introduction to Gy theory, which is the basis for ISM procedures to increase the representativeness of soil data without breaking the budget. Section 3.1 – Systematic Planning and Decision Unit Designation provides a summary of the key aspects of systematic planning and DU design in relation to the collection of soil and sediment samples that have unique applicability or challenges using ISM sample collection. As with any sampling event, characterization must generate data in three dimensions so that data needs are met for a range of technical users who participate in the site investigation process. This means collecting data that inform each step of problem formulation: source area identification, fate and transport, and exposure/risk. Examples illustrate the key aspects of systematic planning and DU design. Section 3.2 – Statistical Concepts and Calculations for ISM answers the question, Why use statistics?” Statistics can be used to answer important questions bearing on decision confidence: Is the sampling and analysis design giving accurate information? Are the data good enough to support confident decisions? Are there enough data points to make decisions? Section 3.3 – Planning for the Use of ISM Data describes the application of statistical concepts to ISM work plans (WPs) for use in decision -making. Specifically, this section will discuss DQOs steps 5 and 6 as they apply to ISM . The intent is to provide a link between the DQOs, the sample plan, and the data quality evaluation (Section 6)....