Septic Tank Questions

[vinny11950]

Need some help figuring out some details on my septic tank.

I pulled the original plans for the septic tank system for my house submitted to the building department so I could find my tank and have it pumped. I don't know much about septic systems so please bare with me.

I have never had the tank pumped and don't know if the previous owner did it either. So lets assume it hasn't been pumped in 10 years. The system works fine, no issues with any of the drains in the house. I am just trying to be proactive. I have been using those little septic tank bio treatment bags that you flush down the toilet.

Anyway, the plans say the system was built in 1972. It has 1 rectangular septic tank (900 gallons, precast) that feeds 2 round cesspools (block).



I pulled out the tape measures and started digging. 3 holes later I think I hit the top of the septic tank. It was getting late so I had to stop.





It's about 24" inches below ground.

My questions are:

1) How much do I dig out? Until I find a manhole cover? Any other inspection ports I should look for?

2) Do I want to look for anything else?

3) When I have it pumped, any other maintenance items I should have done while it is open?

4) Also, I am assuming only the septic tank gets pumped and not the cesspools, correct?

Thank you all who read this.

 

[gzecc]

Need some help figuring out some details on my septic tank.

I pulled the original plans for the septic tank system for my house submitted to the building department so I could find my tank and have it pumped. I don't know much about septic systems so please bare with me.

I have never had the tank pumped and don't know if the previous owner did it either. So lets assume it hasn't been pumped in 10 years. The system works fine, no issues with any of the drains in the house. I am just trying to be proactive. I have been using those little septic tank bio treatment bags that you flush down the toilet.

Anyway, the plans say the system was built in 1972. It has 1 rectangular septic tank (900 gallons, precast) that feeds 2 round cesspools (block).

View attachment 187319

I pulled out the tape measures and started digging. 3 holes later I think I hit the top of the septic tank. It was getting late so I had to stop.

View attachment 187316

View attachment 187317

It's about 24" inches below ground.

My questions are:

1) How much do I dig out? Until I find a manhole cover? Any other inspection ports I should look for?

2) Do I want to look for anything else?

3) When I have it pumped, any other maintenance items I should have done while it is open?

4) Also, I am assuming only the septic tank gets pumped and not the cesspools, correct?

Thank you all who read this.

Yes you need to uncover the cover. (let the pumping company remove it).
When the company opens it, have him inspect the interior (cracks, outlet baffle etc)
Only tank gets pumped.
Put tape around the area so no one falls and gets hurt.

 

[Hogwildz]

Some tanks have two lids. One on each end for inspections. I dug about 2' to find mine, not much fun. I didn't bother digging the other end out to find the lid there. My guy uses a mirror after it's pumped and hosed doe, to inspect the inside.
When I had them come out to pump it, I had them add a riser with new lid to make it much easier to get to. You may want to think about that, so no digging needed with each pump in the future.

 

[peakbagger]

If you have access a to metal detector, the covers frequently have an iron handle cast into them. Many pumping firms tie a piece of yellow or orange rope to the handle so when its dug up in the future the rope shows up pretty easy. Prior to reburying take a good set of swing ties to known points, usually the corners of the house. A lot of folks attach drawing of the house with the swing ties shown on the electrical box cover.

 

[jatoxico]

I have a cesspool, just a simple pool in the ground with an overflow that was added later. I also periodically add enzymes to help break down fats and paper since the system is fairly old.

In my research though I have seen a lot of mixed info on adding enzymes to a septic system. Apparently some folks found that by treating the solids they inadvertently caused blockages down the line since the pools are supposed to receive liquid only. This was especially the case with systems using leaching fields. For routine maintenance I believe you are supposed to have the solids removed every 2-3 years.

 

[mitchell721]

Not sure about the cess pool side of it. I have a leach field. I have 2 part tank you probably do also. Flows into one side from house. Then there's a pipe baffle that goes down on opposite side.(Used to be concrete but they break off due to old age) this is essentially a solid tank then the other side is liquid tank if you will that then disperses it to the field. Or I would imagine in your case the cess pools. To slowly drain. Them solids get to high and that's where things can start to go very bad. When I had the guys out when I bought the house i asked about the packs of enzymes he said to save my money and just dump spoiled milk down the drain when it goes bad and spoiled meat. Also mine was 1000 gal I believe and with 3 of us he said pump it every 3-5 years closer to 3 if we use garbage disposal. Hope this helps

 

[vinny11950]

Yeah, I have also read heated online discussions about adding enzymes.

We don't flush any paper into the system, food or anything that may clog it up. Long Island has great soil drainage which is why I think the system has been able to last as long.

Thanks for the valuable input, guys.

 

[firefighterjake]

A septic system question ... seems like there is one guy here who is a legit expert in this topic ... I expect he'll be along shortly.

 

[mcdougy]

Find the lid is all u need to do. A reputable pumping company will do the rest for you, give you reccomendations. Adding a riser would be wise. Try using some sort of probe to locate your corners of the tank. The lid should be somewhere near the middle of the tank at the end of it. If pumping guy starts talking scary talk, listen, and use common sense from that point.

 

[Highbeam]

So in 1972 you may still have a single large tank with no divider in the middle. I know that my 1963 tank is a single 1000 gallon tank with no divider and only a single manhole in the middle. If yours is divided into two cells then you will have two manhole sized lids. Then , at the inlet and outlet of the tank you will have access ports in the lid to inspect and clear blockages of the inlet or outlet. Those will be smaller, like 8". If you have a divider in the middle of the tank you will sometimes have another one of the small lids in between the two manholes to clear that weir. So anywhere from 5 lids to just 3 depending on your tank style.

Center dividers are actually a stupid decision by regulators that don't understand septic tanks. Each half (sometimes not equal) is a solids separating tank and each must be pumped. Do not let the pumper leave without pumping both sides dry. Do not let him leave some on the bottom for "seed bacteria". That's dumb. No reason to ever add things to the tank other than sewage.

I would uncover all lids for the pump. My location has laws that require risers be added so that the main manhole lids are no longer buried but the small access lids may be buried.

Be there when the tank is pumped. Ask him how "full" it was. Understand that the tank will always be full of sewage but that the solids accumulation starts at zero and slowly increases until failure. So you want to know if it was half full or 10% full so that you know if you can go a longer period before the next pump. It does not hurt a thing except your wallet to have it pumped too often and do not believe anybody that says you don't need to pump it at all. There are solids in sewage that do NOT decompose that will ruin your cesspool/drainfield if allowed to accumulate to the point that they spew out of the septic tank.

 

[peakbagger]

There is a device called a "sludge judge" that can be used to sample the solid depth. The cost to pump the tank isn't steep in most areas and I expect that most folks just get it pumped rather than sample it. The guy who pumped mine had a mirror tilted at 45 degrees that he sticks down the hole. If he sees solid built up on the outlet he recommends searching for the distribution box and seeing if the are any solids that made it to the field.

 

[vinny11950]

All great info, guys. Thanks again.

I asked one neighbor on one side if he had his tank pumped, and he said never (he's been there for 20+ years). I asked my other neighbor and he said he had it done a few years ago.

I will keep digging next weekend when I have time, and will give an update to what I find.

Funny thing is the town is now surveying our neighborhood to install public sewer systems. We think another 6-10 years before we can connect. We are bracing for the taxes to pay for it and the hookup costs. Not sure it is the best plan because we are on the southern shore of Long Island and when hurricane Sandy hit it knocked out a lot of the sewage treatment plants in the low lying towns. Sewage flowed untreated for months until they could fix the treatment plants. Then again, it would be nice to flush toilet paper down the toilet.

 

[jatoxico]

If you're not experiencing any issues why are you not flushing paper? I go with single ply but there's no reason to be concerned to use it normally. Even my simple cesspool is fine handling it.

Solids do have to be removed from a septic system like yours though, that's how they're designed.

 

[Highbeam]

No reason not to flush toilet paper. None of those "wipes" though.

Put a wad of tp in a mason jar full of water and wait a week, or shake it up. You'll see it readily dissolve to dust.

Worry more about synthetic lint from poly based clothing. That stuff doesn't decompose and doesn't sink out of solution in the septic tank.

 

[Highbeam]

I would love to be on sewer. You could flush anything, use a garbage disposal, take three hour showers, etc. It's just very expensive to book up and pay the monthly bill.

We pay almost 400$ to pump out a septic tank about every 5-10 years.

 

[velvetfoot]

I can't see not flushing toilet paper either. No food, cooking oil, anything else, basically.

I located the tank manhole the same way, measuring from either corner of the house to the dimensions shown on the plan filed with the county.

The company I hired to pump out the tank gave me a paver type of marker to put on the surface, over the manhole. Of course it had their name and phone number on it, lol.

A tip one guy gave me is don't get it pumped in the middle of the summer because of the stink-less so in cooler ambient temperature.

In my experience, talking with some acquaintances, the trend seems to be raised beds with electric pumps in the tank. For myself, if things were operating well, I'd leave things well enough alone. There might be companies or agencies that could want you to 'upgrade'. Just my thinking, extrapolating from what I've seen-nothing specific.

 

[peakbagger]

In my experience, talking with some acquaintances, the trend seems to be raised beds with electric pumps in the tank.

Raised beds with pumps generally means that the local soils don't have enough depth to the ground water table or folks who want plumbing in basement on a flat lot.. Many older systems don't meet the current specs yet work well, if someone has a choice avoid the pumped systems if at all possible. One of the more unpleasant and expensive jobs out there is pulling and replacing a failed pump. I have met more than a few folks who despite warning labels on the pump controls, turn off the circuit as the pump alarm is "annoying". The likelihood of freezing the line between the pump and the field is high during winters where the frost goes deep. Unlike a normal system where the underground line drains empty to the tank, a pump up system has a check valve and the line is always full which means its far more likely to freeze. If the check valve fails, then the electric bill is quite high as the system has to refill the line every time anything goes to the pump tank.

 

[maple1]

Can't imagine not flushing toilet paper. What do you do with it if it doesn't go down the toilet? Yee-uch.

Had ours pumped maybe 3 years ago. It was way overdue - had been 17 years since it was installed, never pumped. (Got lazy there). Similar sounding tank, had a cleanout on each end, over inlet & outlet. Think there was a larger manhole in the middle, over the baffle - may have gotten away with just pulling that up. Actually, I cabbaged up a quick short riser out of PT lumber I had laying around to hopefully make it easier next time - and I think I put it over the center manhole. Guy that did it said his hose would fit in each way over the divider.

There was a large accumulation of 'biodegradable' baby wipes on the bottom - trust me, those things don't degrade, & have no place being in a septic system. Otherwise, ours looked good & I think was done just in time. We're down to 3 from 5 occupants now - maybe 2 after next fall. So I might wait another 5 years or so. We also flush the odd bit of food gone bad - liquidy stuff, like the leftover stew that got pushed to the back of the fridge last month...

 

[mark cline]

Learning a lot on this thread . I will have my septic put in this spring . Is it overkill to have 2 -1000 gal tanks then to dist box then leach field ? I don't mind the extra cost , I'm thinking towards the future , I live 1800 ft back off the main road which is dirt/gravel , surrounded by amish families , so I will never have a public sewer line run down my road.
Are the plastic/ fiberglass tanks better than the concrete tanks?

 

[vinny11950]

Can't imagine not flushing toilet paper. What do you do with it if it doesn't go down the toilet? Yee-uch.

Just roll it up into a ball with more TP and throw it in the trash. No one will ever notice, unless you go digging in the trash

 

[peakbagger]

Learning a lot on this thread . I will have my septic put in this spring . Is it overkill to have 2 -1000 gal tanks then to dist box then leach field ? I don't mind the extra cost , I'm thinking towards the future , I live 1800 ft back off the main road which is dirt/gravel , surrounded by amish families , so I will never have a public sewer line run down my road.
Are the plastic/ fiberglass tanks better than the concrete tanks?

Look into something called a Presby system. They are superior to standard septic systems. They take up less room and are much harder to screw up plus they are more effective at cleaning up the leachate.

 

[DickRussell]

Here's the link: http://presbyeco.com/products/advanced-enviro-septic™-wastewater-treatment-system/

We have that for our leach field, actually built on a hillside. It doesn't have to be on level ground. The rows of wrapped pipe run across the slope, with just a slight pitch downward.

As to there being a check valve or bleed-down hole in the pump discharge line, to prevent freezing in a system with a pumpout chamber at the end of the septic tank, to pump to a leach field higher than the septic tank, there was a thread on this here back in 2011: https://www.hearth.com/talk/threads/septic-tank-pumping-up-to-drain-field-check-valve.66524/. It was suggested (post #13) that having a bleed-down hole prevents freezing in the discharge line and that having a check valve in a 2" line is asking for trouble. Perhaps this is a matter of local practice that varies from one region to another.

 

[Highbeam]

Learning a lot on this thread . I will have my septic put in this spring . Is it overkill to have 2 -1000 gal tanks then to dist box then leach field ? I don't mind the extra cost , I'm thinking towards the future , I live 1800 ft back off the main road which is dirt/gravel , surrounded by amish families , so I will never have a public sewer line run down my road.
Are the plastic/ fiberglass tanks better than the concrete tanks?

2-1000 gallon tanks is not as good as 1-2000 gallon tank. Septic tanks work by giving floaters and sinkers time to sink or float away from the middle and then that relatively clean zone in the middle goes to the drainfield. So the longer the sewage resides in the septic tank, the more stuff can sink or float out of the clear zone. This is also the reason that a single 1000 gallon tank with a center divider is dumb. It cuts the residence time in half.

After the scum and sludge layers are established then the anaerobic bacteria get to work eating the solids in those layers.

Plastic tanks are no better or worse than concrete. You're just trying to get a long lasting tank. Be careful in areas of high ground water that you don't float a plastic tank out of the ground if it's emptied.

 

[mark cline]

Look into something called a Presby system. They are superior to standard septic systems. They take up less room and are much harder to screw up plus they are more effective at cleaning up the leachate.

I will look into this type of system . Thanks for the reply.

 

[mark cline]

2-1000 gallon tanks is not as good as 1-2000 gallon tank. Septic tanks work by giving floaters and sinkers time to sink or float away from the middle and then that relatively clean zone in the middle goes to the drainfield. So the longer the sewage resides in the septic tank, the more stuff can sink or float out of the clear zone. This is also the reason that a single 1000 gallon tank with a center divider is dumb. It cuts the residence time in half.

After the scum and sludge layers are established then the anaerobic bacteria get to work eating the solids in those layers.

Plastic tanks are no better or worse than concrete. You're just trying to get a long lasting tank. Be careful in areas of high ground water that you don't float a plastic tank out of the ground if it's emptied.

Very good points I will look into a 2000 gal tank vs 2- 1000 gals. As far as high ground water, don't think that is much of a problem. Thanks for your reply.