This Resource Conservation and Recovery Act (RCRA) Facility Investigation (RFI)/Remedial Investigation (RI) Work Plan has been prepared for the Road A Chemical Basin Operable Unit (RdACB OU) (904-111G). This unit is subject to the requirements of both RCRA and the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA). This Work Plan presents the initial evaluation of existing unit data, applicable background data, the regulatory framework for the unit investigation, and the evaluations and decisions made during the determination of the scope and objectives of the planned Remedial Investigation/Feasibility Study (RI/FS) activities.