Unlike sewer connections within a city  - the septic is fully upon the owner of the property to insure it is in proper working order.  If you are curious about your septic system first check the history of inspections and pumping here:​

https://www.onlinerme.com/(S(wisglnm3ukchlwlscx4jv4jb))/contractorsearchproperty.aspx

 

Both the regulatory and pumping industry recommend that the sludge and scum layer in a septic tank should never be permitted to fill more than about 30% of the septic tank's volume. Therefore, it will take about 5 years for one adult to fill 300 gallons of a 1,000-gallon septic tank with sludge and scum. 

If you need a recommendation for a professional in this area - don't hestitate to reach out.