A conventional system is a tank plus a soil field. Pumping empties the tank so the field is not loaded with sludge. If the field is already damaged, pumping still helps, but it does not rebuild the soil.
An aerobic system still has a trash tank. Pumping that tank is licensed septage work. Repairing an aerator, chlorinator, or spray head is a different trade — see Oklahoma Aerobic Guide for Department of Environmental Quality certified aerobic installers.
Some companies hold both kinds of credentials. This site only republishes the septage pumper roster. Do not assume an installer on okaerobic.com is also a licensed pumper, or the reverse. Ask for the credential that matches the job.
If you are not sure which system you have, look for a control box, an aerator hum, or spray heads in the yard. When in doubt, describe what you see. A good pumper will tell you if you also need an installer.
General information for Oklahoma homeowners, not legal advice and not a booking. Compare companies on the directory and confirm the job directly.