scope:

Purpose and Scope.

This handbook provides technical guidance to USACE risk assessors and risk assessment support personnel for planning, evaluating, and conducting ecological risk assessments (ERAs) in a phased Hazardous, Toxic, and Radioactive¹ Waste (HTRW) response action and Military Munitions Response Program (MMRP) projects with munitions constituents (MC). This handbook, a compendium to the Risk Assessment Handbook: Volume I - Human Health Evaluation (EM 200-1-4, USACE 1999), encourages the use of "good science" within the framework of existing U.S. Environmental Protection Agency ERA guidance.

Risk characterization is a similar process for both human health and ecological risk assessments. The fundamental paradigm for human health risk characterization has four phases: (1) hazard identification, (2) dose-response assessment, (3) exposure assessment, and (4) risk characterization. Similarly, the fundamental framework for ecological risk characterization includes four analogous phases: (1) problem formulation, (2) exposure characterization, (3) ecological effects characterization, and (4) risk characterization. Waste (HTRW) response action and Military Munitions Response Program (MMRP) projects with munitions constituents (MC). This handbook, a compendium to the Risk Assessment Handbook: Volume I - Human Health Evaluation (EM 200-1-4, USACE 1999), encourages the use of "good science" within the framework of existing U.S. Environmental Protection Agency ERA guidance. 

This handbook encourages the concurrent assessment of human and ecological risks so that data collection activities are coordinated and risk managers are provided risk characterization results in a timely manner. Risk characterization results for human and ecological receptors should be reasonable and communicated to the risk managers in a clear and unbiased manner to facilitate the making of balanced and informed risk management decisions. 

For the purpose and intended use of this risk assessment handbook, the focus is on the Defense Environmental Restoration Program (DERP) and Base Realignment and Closure Program (BRAC) cleanup programs to address CERCLA- and RCRA-related issues. EM 200-1-4 (USACE 1999), Risk Assessment Handbook, Volume I: Human Health Evaluation, contains a complete discussion of the USACE HTRW program, which will not be repeated here. The reader is referred to that document for details. 

¹ Note that radioactive hazards, radioactive wastes, radiation generating devices and radioactively contaminated materials are not addressed in this handbook.

Applicability. This manual applies to all HQUSACE elements and USACE commands responsible for HTRW and MMRP projects with MC.