3.1 Overview of Systematic Planning
Environmental data must be of the appropriate type, quantity, and quality to manage uncertainty and reach defensible decisions. To ensure that the data obtained during environmental investigations are adequate for their intended purposes, it is strongly recommended that data collection activities be planned and developed through a systematic planning process, including the development and consideration of a conceptual site model. The planning process should also take into account the decision mechanisms for which the data will be used (Section 7 offers an extensive discussion of decision mechanisms). Establishing clear objectives at the beginning of the investigation is crucial to efficient and effective characterization of the site. As described in this section, good systematic planning is reflected in the field through well-thought-out DUs and SUs that are sampled to answer key investigation questions.Establishing clear objectives at the beginning of the investigation is the key to obtaining data that will support well-informed management decisions.
As described throughout this document, the use of incremental samples to characterize the soil within a DU can provide higher-quality data and fewer decision errors than conventional low-density discrete or composite sampling designs. In combination with well-considered investigation objectives and DU and SU designations, incremental samples can reduce the need for additional sample collection, increase the certainty of decisions, and reduce the time and money required to complete environmental projects. Although a project team may have an ISM strategy in mind during initial planning, a number of sampling and analysis options should be considered, and the sampling strategy selected should be an outcome of the systematic planning process.
The systematic planning process identifies the objectives of the site investigation and establishes the type of information needed to make an environmental decision. The level of detail needed to adequately incorporate a systematic planning approach into a data collection effort varies from project to project; larger or more complex projects typically warrant more detailed planning than smaller, simpler projects. The nature of the ISM process is such that many decisions must be made and detailed plans established and disseminated in advance of sample collection. For these reasons, the principles of the systematic planning approach should be applied on every ISM project.
With ISM it is critical to understand the objective of the investigation since it may determine the type, location, and dimensions of DUs. A clear understanding of the study objectives is important with all sampling strategies, but particularly so with ISM sampling. Different types of objectives may dictate the type, location, and dimensions of DUs. For example, the identification and investigation of small source-area DUs may be especially important for highly mobile chemicals that can pose significant vapor intrusion or leaching risks. In other situations, larger exposure-area DUs or subsurface DUs are appropriate to evaluate risks to specified receptors. ISM should not be used in situations where the resulting data will not meet the project objectives or answer the questions indicated by the systematic planning process or where it cannot be implemented within the constraints of the project. These caveats, however, apply to any potential sampling and analysis strategy.
Systematic planning involves a series of well-considered steps that result in clear data collection plans and objectives. The USEPA DQO process and the U.S. Army Corps of Engineers (USACE) technical project planning (TPP) process are two examples of systematic planning frameworks that can readily be used with ISM. Guidance documents which describe the DQO process as well as other systematic planning processes are listed below:
- A Guideline for Dynamic Workplans and Field Analytics: The Keys to Cost-Effective Site Characterization and Cleanup (Robbat 1997)
- Technical Project Planning (TPP) Process (USACE 1998)
- Data Quality Objectives Process for Hazardous Waste Site Investigations: Final Guidance (USEPA 2000a)
- Using the Triad Approach to Improve the Cost-Effectiveness of Hazardous Waste Site Cleanups (USEPA 2001)
- Guidance on Systematic Planning Using the Data Quality Objectives Process EPA QA/G-4 (USEPA 2006b)
- Improving Environmental Site Remediation through Performance-Based Environmental Management (ITRC 2007a)
- Best Management Practices: Use of Systematic Project Planning Under a Triad Approach for Site Assessment and Cleanup (USEPA 2010a)
- Technical and Regulatory Guidance for the Triad Approach: A New Paradigm for Environmental Project Management (ITRC 2003)
- Triad Implementation Guide (ITRC 2007b)