scope:

The CSM development process in this manual is applicable to any phase of an OE or HTRW project. These include investigation, design, response phases, and during operation/maintenance of remedial systems with recurring review. The CSM is not a separate deliverable, but a component of existing documents such as work plans, sampling and analysis plans, site characterization reports, final removal reports, or similar documents as determined by the team. This process may be applied under any regulatory framework.

Purpose. This Engineer Manual (EM) provides U.S. Army Corps of Engineers (USACE) and other personnel with procedural guidance to develop Conceptual Site Models (CSMs) at sites potentially containing ordnance and explosives (OE) and/or hazardous, toxic, and radioactive waste (HTRW) environmental contamination. The CSM is a description of a site and its environment that is based on existing knowledge. It describes sources and receptors, and the interactions that link these. It assists the team in planning, interpreting data, and communicating. The CSM will provide a planning tool to integrate information from a variety of resources, to evaluate the information with respect to project objectives and data needs, and to respond through an iterative process for further data collection or action. The target audience is the project delivery team (PDT).

Applicability. This manual applies to all Headquarters, U.S. Army Corps of Engineers (HQUSACE) elements, USACE Major Subordinate Commands, USACE geographic districts, and field operating activities having responsibilities for civil works and/or military programs with OE and HTRW-related issues. This guidance is provided to assist any organization or PDT involved in evaluation and decision-making. The CSM development process in this manual is applicable to any phase of a project, including investigation, design, response, and operation and maintenance of remedial systems with recurring review.