Forgive the length of this message. I don't know what facts are important and wish to provide as much information as I can. I put all my questions at the end.
Our septic drainfield (probably put in in 1995 by the previos owners) started to be soggy in one spot. The remaining part of the field seems dry. The system is on the side of a hill. We don't have plans for the field and so we don't know exactly how it is layed out. We have no idea where the distribution box is.
We have dug the soggy area up and found that around the pipe (the lowest one in the field) the water was pooled and of course that is why the water was seeping to the surface. The drainfield is down hill and to the right of the septic tank (the septic tank was cleaned last summer and is working okay). The pipe we found is sloped (looking from the top of the hill) from the bottom left towards the upper right of the hill. The hill slopes a bit from east (lowest) to west (highest) and slopes quite a bit from south (lowest) to north (highest).
Anyway, we drained that standing water off and knocked on the pipe near a joint in the piping, thinking that the joint was leaking.
What happened was almost immediately the pipe started draining freely and at a heavy weight, both water and a bit of scum (the scum looks like the stuff I find in the bathroom drain when I clean out the hair and other juck). After several minutes, the flow slowed and so we left it to see what would eventually happen. The flow stopped and the area around the pipe dryed out. It appears that the natural seepage is still working as some portions of the pipe trench could only seep through the sides of the trench. Oh, the water runs out from the upper right to the lower left.
This makes us think that the problem is that the pipe or pipes are blocked some what. We have monitored it during our normal usage (showers and toilets, etc.) and the only time there is a lot of water is when our green sand water filter is flushing. Other than that water is able to come from the pipe, but in an amount that the surrounding area should be able to handle.
The questions I have are as follows:
1) Why would the drainfield be built so that the pipes are sloped from the upper right to the lower left when the septic tank is to the upper left of the drainfield?
2) Where would the distribution box most likely be? To the upper right or upper left of the drainfield?
3) Is there any way, without digging up the entire field (we are doing it by hand because we can't afford to hire someone) to tell if the other pipes are working correctly?
4) What does working correctly mean? How much water should be coming out of the pipe if we use the garden hose to put water in the second compartment of the septic tank? A lot or just a little?
5) Is there any way that we can have the pipe or pipes cleaned out? Hopefully by ourselves as we can't afford to hire someone.
We would really appreciate any help you can give me. We would like to have the problem fixed as soon as possible.
It may be that the previous owners did not have the tank pumped often enough. This can cause some solids to be flushed into the leech field. This is not good, since the field is designed only for liquids. Get too much down there and you can quickly clog it and require a replacement. Sound like there was a clog there that the knocking dislodged, pushing it further down the slope. Depending on how far, from that point down, it is probably still blocked. The best practice is to get the tank pumped regularly. This somewhat depends on the number of people, the size of the tank, and how consciences you are about what you put down the drain. Somebody that works with these things regularly can better help with details.
Important note - I'm not a pro
Retired Defense Industry Engineer; Schluter 2.5-day Workshop Completed 2013