4.1 The intended use of this guide is to provide practical assistance in the development of an optimized sampling design. This standard describes or discusses:
4.1.1 Sampling design selection criteria,
4.1.2 Factors impacting the choice of a sampling design,
4.1.3 Selection of a sampling design,
4.1.4 Techniques for optimizing candidate designs, and
4.1.5 The criteria for evaluating an optimized sampling design.
4.2 Within a formal USEPA data generation activity, the planning process or data quality objectives (DQOs) development is the first step. The second and third are the implementation of the sampling and analysis design and the data quality assessment. Within the DQO planning process, the selection and optimization of the sampling design is the last step, and therefore, the culmination of the DQO process. The preceding steps in the DQO planning process address:
4.2.1 The problem that needs to be addressed,
4.2.2 The possible decisions,
4.2.3 The data input and associated activities,
4.2.4 The boundaries of the study,
4.2.5 The development of decision rules, and
4.2.6 The specified the limits on decision error.
4.3 This guide is not intended to address the aspects of the planning process for development of the project objectives. However, the project objectives must be outlined and communicated to the design team, prior to the selection and optimization of the sample design.
4.4 This guide references statistical aspects of the planning and implementation process and includes an appendix for the statistical calculation of the optimum number of samples for a given sampling design.
4.5 This guide is intended for those who are responsible for making decisions about environmental waste management activities.
Область применения1.1 This document provides practical guidance on the selection and optimization of sample designs in waste management sampling activities, within the context of the requirements established by the data quality objectives or other planning process.
1.2 This document (1) provides guidance for selection of sampling designs; (2) outlines techniques to optimize candidate designs; and (3) describes the variables that need to be balanced in choosing the final optimized design.
1.3 The contents of this guide are arranged by section as follows:
1.
Scope
2.
Referenced Documents
3.
Terminology
4.
Significance and Use
5.
Summary of Guide
6.
Factors Affecting Sampling Design Selection
6.1
Sampling Design Performance Characteristics
6.2
Regulatory Considerations
6.3
Project Objectives
6.4
Knowledge of the Site
6.5
Physical Sample Issues
6.6
Communication with the Laboratory
6.7
Analytical Turn Around Time
6.8
Analytical Method Constraints
6.9
Health and Safety
6.10
Budget/Cost Considerations
6.11
Representativeness
7.
Initial Design Selection
8.
Optimization Criteria
9.
Optimization Process
9.2
Practical Evaluation of Design Alternatives
9.3
Statistical and Cost Evaluation
10.
Final Selection
Annex A1
Types of Sampling Designs
A1.1
Commonly Used Sampling Designs
A1.2
Sampling Design Tools
A1.3
Combination Sample Designs
Appendix X1. Additional References
Appendix X2. Choosing Analytical Method Based on Variance and Cost
Appendix X3. Calculating the Number of Samples: A Statistical Treatment
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.
1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.