New house - ET (evapotranspiration septic)

[stevestk]

I just got an inspection for a house I'm purchasing. The inspector described the system as follows. Two septic tanks. Solids should settle in first with liquids flowing to second. From the second it goes through a filter bed. From filter bed it goes to a sump where it is pumped through pipes close to the surface where it evaporates. I've since learned this is called an ET system. Had visual access only to cover on first tank and the sump. could not see into second tank or see tank baffles. He flushed dye in toilet which was seen in first tank. He ran water for 35 minutes (~220 gallons) and no water ever showed up in sump. Water level didn't rise in first tank so it was going somewhere. Inspector said it could be staying in second tank if it wasn't full enough to overflow. I should mention no one has been in the house for the past week. He also said the cover to the second tank was probably a foot or so underground and gave an estimate of where it should be. There should also be access to see baffles? He said ideally you want to be able to verify solids aren't moving to second tank and filter bed. Also the last recorded pump out was 2012 and for 1000 gallons which indicated probably only the first tank was pumped. Expectation if that's true would be the tanks would be pretty full?

Questions:
Explanation for water not getting to sump during test?
Does this type of system work effectively (I'm in Ohio, what about winter)?
Is the ground always wet?
How deep are the pipes?
Kids can play in that part of the yard?

I'm thinking of asking the seller to verify system including locating and uncovering access ports, possibly a pump out, and further validating the system is working.
Thoughts?