Purpose: This engineer pamphlet (EP) will give United States Army Corps of Engineers (USACE) risk assessors the recommended basic/minimum requirements for scopes of work (SOW) to procure Architect-Engineer (A-E) services for preparing human health and ecological risk assessments for Hazardous, Toxic, and Radioactive Waste (HTRW) projects. These HTRW projects are regulated under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), as amended by the Superfund Amendments and Reauthorization Act (SARA) of 1986, and the Resource Conservation and Recovery Act (RCRA), as amended by the Hazardous and Solid Waste Amendments (HSWA) of 1984. The SOWs contained in Appendices A and B are a starting point only. They can be changed by use of the Technical Project Planning (TPP) Process (EM 200-1-2) and this is acceptable and advisable.