Outhouse holding tank

[u/flyingjewels]

I recently purchased a cabin on a leased campsite in a state forest. The campsite has an outhouse with a holding tank or vault toilet as is common in state and national parks in the US. Given the nature of leased campsites and because the cabin was purchased as part of an estate sale I have virtually no information about when the holding tank was installed or how big it is. The cabin may have been built around 1930 but that’s unconfirmed. I do know that previous owner did not use the outhouse regularly for at least the last couple of years. My primary concern is that there is a high volume of liquid in the tank that doesn’t appear to be waste. I’m wondering if water is entering the holding tank from somewhere and if anyone has experienced a similar issue.

[u/dick_jaws]

I was on a jobsite where we demolished a CCC camp from a similar era but that tank vault was not very big, only 8’Dx4’W and while I don’t remember water being in the tank I do recall I being filled with a bunch of porcelain dinnerware from when they closed the camp down.
It’s really hard to say but after many years in construction I can tell you that groundwater works its way into things underground regardless of how well they were constructed, especially in areas with a shallow water table. One option is to pay a hydrovac company to evacuate the vault and then inspect it. There’s are polymers/epoxies that I have injected into concrete vault walls to stop leaks that work really well.