School me on septic tanks. Where's the lid?

[Rot Box]

I've lived in my house six years and have no idea when the last time the septic was pumped---crappy deal I know

I'd like to have it serviced before it explodes in my back yard. How do you find the lids for these things? I tried walking around the yard witching and also looking at the plumping which gave me a general idea of where it 'might' be but I'd really like to find the clean out/lid without destroying my yard. Any ideas would be greatly appreciated.

Andrew

 

[Unimog]

Wherever the grass is greenest . It will likely be buried under a few inches or a foot of soil - probably about a foot around. Poke around with a long screwdriver. I don't think the pros that I have seen have any better method other than intuition.

 

[Spork]

The county may have plot plans that tell you where it is. of course if someone has landscaped and changed slope or something it may be deeper. One of my old neighbors bought a house with a septic tank and his was down about 5 feet.

 

[SpeedyVic]

Hi Andrew! I used to be in the plumbing business (Baugh Plumbing Co.) in Cahe Valley, and we have done a bunch of septic work. What makes you think you need to clean out your tank?

To answer your question, the tank "should" begin close to your foundation (usually within 36") and then the leach field will usually begin within 36" of exiting the tank and extending out to however far they determined they needed to go at the time of install.

Now, I say "should" and Usually cause, depending on how old your house is, the Plumber, Building Inspector, and the health Department people, sometimes play a little fast and loose on the way the interperet the regs.

Now, if your tank was installed according to the common practices of the era, and you have been careful in your water usage paractices, you shouldn't ever have to do anything with your tank. A properly functioning tank will digest just about anything that gets flushed into it, unless you are flushing plastics and lots of oils. Also, a leaky faucet can cause the tank to flood and then not digest the way that it should.

A functioning tank will contain aerobic and anaerobic bacteria that will digest just ablout all organic solids in a pretty efficient manner. This digestive process breaks the solids down into effluent that is then disharged out of the tank and into the leach field where the waste water is then allowed to percolate back into the ground. This system, if done correctly for the area, is generally pretty robust. Unless some unforseen event (flooding?) happens, most septic systems will never need any sort of maintenance.

Hope that helps!

 

[SpeedyVic]

Oh, one more thing. If you pump out a properly functioning tank, you can actually make the tank work worse. By removing material and water from the tank, you also remove the bacteria that is in there. This bacteria takes time to grow, and by removing it, you could be introducing a situation where the bacteria is not in balance with the system that it needs to sustain.

 

[rholbrook]

Look for the low spot in your lawn. Dirt will settle over time. Speedy is right about the bacteria.

 

[mesha]

we used a metal detector to find mine.

 

[UNSTUCK]

Here's a not so fond memory:

I used to work for a pipeline company. They got a job once tearing out the septic tank for an elementary school and tying their plumbing into the city lines. This tank was about 30ft x 30ft and about 10ft deep. As they started breaking the concrete with 'hoe's they found that they could not get through the rebar. They called me out to cut out all the rebar with the torches on my truck. I was crawling out over the middle of this now-open tank cutting the rebar. As I would cut it, they would fall into the POOP and splash up on me. I was not happy.

So, I hate septic tanks.

 

[mesha]

I was going to let everyone know that they shouldn't stand inside septic tanks while rebar is falling in them, but thought, "no one needs to hear that, that is a given."


I guess I was wrong.

 

[muleskinner]

Hi Andrew! I used to be in the plumbing business (Baugh Plumbing Co.) in Cahe Valley, and we have done a bunch of septic work. What makes you think you need to clean out your tank?

To answer your question, the tank "should" begin close to your foundation (usually within 36") and then the leach field will usually begin within 36" of exiting the tank and extending out to however far they determined they needed to go at the time of install.

Now, I say "should" and Usually cause, depending on how old your house is, the Plumber, Building Inspector, and the health Department people, sometimes play a little fast and loose on the way the interperet the regs.

Now, if your tank was installed according to the common practices of the era, and you have been careful in your water usage paractices, you shouldn't ever have to do anything with your tank. A properly functioning tank will digest just about anything that gets flushed into it, unless you are flushing plastics and lots of oils. Also, a leaky faucet can cause the tank to flood and then not digest the way that it should.

A functioning tank will contain aerobic and anaerobic bacteria that will digest just ablout all organic solids in a pretty efficient manner. This digestive process breaks the solids down into effluent that is then disharged out of the tank and into the leach field where the waste water is then allowed to percolate back into the ground. This system, if done correctly for the area, is generally pretty robust. Unless some unforseen event (flooding?) happens, most septic systems will never need any sort of maintenance.

Hope that helps!

How does the aerobic bacteria survive without oxygen? I could see the anaerobic bacteria thriving, not too sure about the aerobic.

Not sure on locating your tank, but like Vic mentioned, you should only pump it out if you have a problem.

 

[Rot Box]

Wow thanks everyone I appreciate the info I'm not having any issues right now for whatever reason I was thinking they had to be pumped out fairly often... So this is good news. I know the leach field was extended at some point in the late 90's but that's all I know as far as improvements go. I flush those packets every month which should help things I guess.

UNSTUCK, that's too funny. I'm picturing Joe Dirt---I got the poo on me make it stop

 

[SpeedyVic]

How does the aerobic bacteria survive without oxygen? I could see the anaerobic bacteria thriving, not too sure about the aerobic.

Not sure on locating your tank, but like Vic mentioned, you should only pump it out if you have a problem.

The way that a tank is designed, the water level should never completely fill it up. As waste material enters the tank, the stuff that floats, and the stuff that sinks, should be allowed to do so respectively. So material that sinks gets digested by the anaerobic bacteria, and the stuff that floats gets digested by the aerobic bacteria. The discharge pipe should exit the tank somewhere close to midheight of the tank.

So picture the tank from the side view. Sludge is in the bottom, floaties on the top with an air pocket above. And a layer of "clean" effluent in the middle. This effluent is what gets discharged into the drain field.

A septic tank is not completely air tight. Air is allowed in through the lid and can usually get there through the layer of dirt above. In special applications where the tank is going to be buried deep, a vent will be used.

Btw, a healthy septic tank will not stink when the manhole is open. It may smell like wet fertile soil but nothing that will make you gag.

 

[SpeedyVic]

Another FYI: it's a common misconception that the drainage system in your house is always full of water. This is not the case. The drain pipes are dry 99% of the time and should never "hold" water. They are meant to convey water to the sewer or septic system. Even the sewer line from your house to the street should be dry. The only time there should be water in it is right after you've flushed our poured water into a drain in the house, and only contain water for as long as it takes for the water to run through it to its intended destination.

So the septic tank can also "breathe" by way of the empty drain lines that are vented through the roof of the house.

 

[SLC97SR5]

FWIW, we have never had the tank pumped at our cabin and a few years ago thought we should check on it.

We popped the top and found it about half full with only "indigestibles" (shiny metallic candy wrappers) floating on top.

The cabin has been there for 50+ years...that's a lot of turds.