Septic tank issues

[jchealey]

I have a septic tank that was originally installed in 1957. There was a new lid put on in the 80s as the original was redwood. The new lid was concrete if I read the permit correctly. We bought this house last year and have noticed that within 10 feet of the tank, you can smell a faint odor. The tank is under ground at least 1 foot but could be more. There is no sign of the leach lines anymore but no leakage or smell from where they should be. I was wondering if the new lid is no a good seal and there could be leakage. There are two trees within 15 feet of the tank and they could have put a root into the tank or something. This was originally listed as a 1000 gal tank. We pumped it before buying the place and the guy said he pumped 1200 gallons.

Any ideas?

[mrcaptainbob]

"no sign of leech lines....*anymore*....". You were able to see them when you first purchased the house? And you don't see them now? And there's a 'faint' odor near by the tank? I would have the tank pumped again. That leech field is 50 years old. I'm surprised it was working good enough to have passed the inspection. 'Coarse, some 'crapped' out sooner, and many are working for a longer time than that, I'm sure. But, getting the tank pumped is the easiest way to define the field's existing condition. If there's a sucking sound and water comes pouring from the field side when the water level is lowered, then the field's clogged. There should be a thick 'layer' on the water top when the lid is first lifted. No moist dirt should be evident near or around the tank or lid. There was a thread here a while back on septic sytems with a LOT of great info. Try a search and check out the mentioned sites.

[jchealey]

The leach field has been used as horse pasture for years. I can guess where some of the trenches are but you really can't see them. We did have the tank pumped and that went well. I guess what I was worried about is if you can put a new lid on a tank and keep it sealed.

[mrcaptainbob]

I've heard a lot of talk about driving heavy equipment (cars. etc.) over the drain field. It's not recommended. Midsized tractooors are apparently okay. But I'd be worried about how much weight is placed on the small area from a horse hoof. Can't be good if it compacts the ground around the tiles. I doubt it would crack any of them, but when it's 50 years old, I'd try to be as careful with it as possible. As for that lid, if it was sized to the hole properly, there should be no trouble with it. Incidentally, try posting this question in the plumboing section, there's some really knowledgeable people there that can give you far better help than I.