How do Certifications and Subdivision Approvals fit into this COSE/AOSE heirarchy? When we certify property we certify an area for all types of possible systems. After doing a site and soil evaluation, then and only then is the system type decided. Since only an abbreviated design is necessary for a Certification/SubDivision Approval and not a complete system design I believe any Authorized/Licensed OSE should be able to do this type of work.

This whole COSE vs. AOSE idea seems very archaic and doesn't make much sense for a lasting "OSE" program.  

All CPSS's can do soil but not all CPSS's can design onsite systems...some engineers can design onsite systems but relatively few can do soil.........AOSE's are trained to do both and yet we are required to meet the most stringent of onsite soil and design qualifications.