The OCCSS software is a version of a mainframe-based application developed for the EPA's National Contract Laboratory Program (CLP). OCCSS is designed to automate the determination of contractual compliance and completeness of data submitted to EPA under the RAS programs of CERCLA (Comprehensive Environmental Response, Compensation, and Liability Act) and SARA (Superfund Amendments and Reauthorization Act). The manual provides the user with instructions for running OCCSS software on the PC. Descriptions of and instructions for each menu are detailed in the following sections. The user should have a working knowledge of PC DOS prior to utilizing this system. The following sections present the OCCSS operating environment, describe system output (reports), provide instructions for running the system and generating reports, and specify input data requirements. Examples of reports are contained in Appendix A. Appendix B contains descriptions of sample suffix codes and report defect codes. Appendix C is a listing of defect statements by criterion, with associated SOW references. Appendix D contains data file formats from Exhibit H of the SOW. Since OCCSS PC software is implemented using Base SAS Software, the 'SAS Language Guide for Personal Computers' from The SAS Institute, Inc. in Cary, North Carolina may be helpful.