Around the lakes, the system you're repairing was often built for a different house. Fishing cabins became four-bedroom weekend homes; a single-wide was replaced with a double-wide on the same pad; a basement was finished with a bathroom that drains to a tank sized for two. The first step on any repair is finding the original permit and comparing what was permitted with what the house is now asking of it. If the county has a record of the system, it shows where the tank and field are, which saves digging.
Next is the tank. Once a pumper empties it, the walls, tees, filter and inlet and outlet pipes are visible. Concrete tees and baffles break off, outlet filters pack with lint and grease, and older tanks may have no filter at all. If the outlet baffle has been missing for a while, solids have probably reached the field, and that gets checked next instead of assumed.
After the tank comes the distribution box. Georgia's manual says the box has to sit on a firm foundation so it can't rock, and the way to test it is to pour water in and watch every outlet run at the same time (DPH Manual). On sloped lake lots, boxes settle downhill, and one trench quietly takes the whole flow until it fails. Releveling or replacing the box, sometimes with flow-equalizing caps on the outlets, can put the rest of the field back to work.
On a pumped system, the pump, floats, alarm and control panel get checked in place. Lake houses lose power in storms, and a pump tank with too little reserve space can fill and back up before the lights come back. The fix may be the pump itself or the controls; our septic pump systems page covers those repairs in depth.
Only when the tank, pipes, box and pump all check out does the drain field itself get the blame. If it's the field, the same crew that diagnosed it digs it, under the same conversation with Environmental Health. That work has its own page: drain field installation and repair.
Shoreline lots add one more check. Repair work stays off Georgia Power land, and on Lake Oconee any mechanical clearing or regrading inside the 25-foot vegetative buffer or on project lands needs Georgia Power's written approval first (Georgia Power). Georgia Power does consider tree removal requests to make way for septic installation, with 1:1 replanting, so a repair that needs a tree out can usually be planned around.