Seepage pit question
#1
07-24-16, 08:26 AM
Seepage pit question
Hello, the seepage pit installed for this home is about 38 years old. It is a horizontal pit measuring about 47'x4'x 6' (L W D), lined with wood and a rocky or gravel bottom. Overall, it seems to be functioning well.
After moving into the house about 8 months ago, the pit was filled to about 30".
I installed low flow items throughout the home and rerouted the laundry to a separate grey water system.
Currently, the seepage level is about 24". It won't drop any farther, but does increase an inch or two on heavy water days and returns back to the 24" level.
I'm thinking biomass from the age of the system and percolation is minimal below this level. The system seems more than ok, I mean, it ain't broke.
My question is
Would it be good or bad to pump out the pit? If the biomass is exposed to air, will it dry out and be worse or helpful?
Unsure if my thought process on this is correct, looking for advice/input.
Thanks
After moving into the house about 8 months ago, the pit was filled to about 30".
I installed low flow items throughout the home and rerouted the laundry to a separate grey water system.
Currently, the seepage level is about 24". It won't drop any farther, but does increase an inch or two on heavy water days and returns back to the 24" level.
I'm thinking biomass from the age of the system and percolation is minimal below this level. The system seems more than ok, I mean, it ain't broke.
My question is
Would it be good or bad to pump out the pit? If the biomass is exposed to air, will it dry out and be worse or helpful?
Unsure if my thought process on this is correct, looking for advice/input.
Thanks
#2
07-28-16, 12:48 PM
Alternatively it might be the water table (ground water level). If you were to dig or drill another hole, at least 4 inches in diameter and about 5'' away from the seepage pit, and find that hole, given an hour, fills up to the same level as the ssepage pit water level, then you are dealing with a water table issue. Given that the pit is 6' deep and the water depth rests at 2', you have up to the level of the inlet pipe, hopefully at least another foot, maybe more if it is significantly uphill to the septic tank and house, before you have to worry about it.
Don't touch the seepage pit for now. Many towns no longer allow seepage pits and also don't let you make changes to an existing seepage pit.
Don't touch the seepage pit for now. Many towns no longer allow seepage pits and also don't let you make changes to an existing seepage pit.
#3
07-28-16, 08:06 PM
Well, thank you for your reply. For awhile, the do-it-yourself website was taking on new meaning.
The water table is a non-issue, the home is situated in a canyon several hundred feet above the seasonal stream below. Homes nearby at similar elevations, have vertical seepage pits drilled 45-50ft. Other homes below us on the downslope would have serious issues if ground water was present at our level.
No ground water issues.
Our pit rests 10-15 below the septic tank due to the topography of the lot.
I believe, percolation has substantially decreased below the 24" level due to the pit being so old. This would be expected after 38 years. It's clear the soil is real good here. That being said, my question remains.........Would it be good or bad to pump out the pit? If the biomass is exposed to air, will it dry out and be worse or helpful? Will it seal the deal like cement, or breakdown a bit for better percolation?
The water table is a non-issue, the home is situated in a canyon several hundred feet above the seasonal stream below. Homes nearby at similar elevations, have vertical seepage pits drilled 45-50ft. Other homes below us on the downslope would have serious issues if ground water was present at our level.
No ground water issues.
Our pit rests 10-15 below the septic tank due to the topography of the lot.
I believe, percolation has substantially decreased below the 24" level due to the pit being so old. This would be expected after 38 years. It's clear the soil is real good here. That being said, my question remains.........Would it be good or bad to pump out the pit? If the biomass is exposed to air, will it dry out and be worse or helpful? Will it seal the deal like cement, or breakdown a bit for better percolation?
#4
07-29-16, 07:49 AM
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get some caustic soda (cesspool cleaner) and mix with water (after the pit is pumped out) caustic soda is powerful stuff, that will clean the walls and bottom of your pit..
#5
07-29-16, 07:37 PM
"Would it be good or bad to pump out the pit?"
If you are going to try caustic soda or caustic anything, then you must pump out the pit completely. Othrwise the chemical will become diluted by the remaiing pit contents and lose most of its power. (Or you will need to use a lot more chemical to get back to the needed concentration.)
If you are going to try caustic soda or caustic anything, then you must pump out the pit completely. Othrwise the chemical will become diluted by the remaiing pit contents and lose most of its power. (Or you will need to use a lot more chemical to get back to the needed concentration.)
#6
07-29-16, 08:58 PM
Caustic soda......lye......sodium hydroxide.
Sounds interesting, never considered. Among many other things.......
Sodium hydroxide is used in the home as a type of drain opener to unblock clogged drains, usually in the form of a dry crystal or as a thick liquid gel. The alkali dissolves greases to produce water soluble products. It also hydrolyzes the proteins such as those found in hair which may block water pipes. These reactions are sped by the heat generated when sodium hydroxide and the other chemical components of the cleaner dissolve in water. Such alkaline drain cleaners and their acidic versions are highly corrosive and should be handled with great caution.
No experience with this, bottom-line, pit is working and don't want to f**k it up, but would like to see perc below 2' level.
Sell me on this, pretend I'm family. :-)
Thanks for all the input.
Sounds interesting, never considered. Among many other things.......
Sodium hydroxide is used in the home as a type of drain opener to unblock clogged drains, usually in the form of a dry crystal or as a thick liquid gel. The alkali dissolves greases to produce water soluble products. It also hydrolyzes the proteins such as those found in hair which may block water pipes. These reactions are sped by the heat generated when sodium hydroxide and the other chemical components of the cleaner dissolve in water. Such alkaline drain cleaners and their acidic versions are highly corrosive and should be handled with great caution.
No experience with this, bottom-line, pit is working and don't want to f**k it up, but would like to see perc below 2' level.
Sell me on this, pretend I'm family. :-)
Thanks for all the input.
#7
07-30-16, 04:05 AM
Whatever you do should NOT be destructive of the colony of beneficial bacteria that you have working down there now . . . . so be careful. Those compounds may be helpful in clearing up a clogged system that isn't working.
But you have a system that IS working, so beware of the law of unintended consequences.
But you have a system that IS working, so beware of the law of unintended consequences.
Last edited by Vermont; 07-30-16 at 04:22 AM.
#8
07-31-16, 06:50 AM
Yes, I am very wary of messing up the pit with chemicals. Although most of the bacterial action happens in the tank, there is some in the pit.
I guess pumping the pit is worth a shot, there is about 2800 gallons in there at the 24" level.
Only about 100 gallons a day is flowing into the system, so it would refill back to the same level in about a month if perch is minimal below the 24" level.
Not a lot of time for anything to really dry out.
Might be a waste of time and money. But shouldn't hurt anything.
My initial question still remains.
I guess pumping the pit is worth a shot, there is about 2800 gallons in there at the 24" level.
Only about 100 gallons a day is flowing into the system, so it would refill back to the same level in about a month if perch is minimal below the 24" level.
Not a lot of time for anything to really dry out.
Might be a waste of time and money. But shouldn't hurt anything.
My initial question still remains.
#12
08-05-16, 05:58 AM
Sodium Hydroxide will cause a wide variety of organic matter and grease to decompose rapidly. Except you are not sure to what extent the dirt directly under the seepage pit has become impregnated by grease and/or fine inorganic matter. So pumping the pit and laying down a good dose of sodium hydroxide will still be hit or miss.
Renewal of septic system leach fields includes digging up the dirt surrounding the leach lines, which dirt is typically impregnated with grease and biomat and fine particulate inorganic matter, and disposing of that, then bringing in new sand. More often these days, new homes with septic systems have a second leach field area laid out so in the event of failure, the old leach field and dirt are abandoned in place and the new leach field installed in the new porous area.
Renewal of septic system leach fields includes digging up the dirt surrounding the leach lines, which dirt is typically impregnated with grease and biomat and fine particulate inorganic matter, and disposing of that, then bringing in new sand. More often these days, new homes with septic systems have a second leach field area laid out so in the event of failure, the old leach field and dirt are abandoned in place and the new leach field installed in the new porous area.
#14
09-10-16, 06:45 AM
Ok.....more info for the thread.
And interpretation......
After more inquiries about my 'pump or not to pump the seepage pit'.....one source said,
this would reduce percolation due to the loss of the weight of the water.
In other words, the hydraulic pressure, exerted by the sheer weight of water at about 8 lbs/gallon, helps to push fluid into the soil. His theory is the last half of a pit lasts longer and works better than the first half due to all this weight.
That being said, pits still fill up and fail after enough time.
But, does the last half percolate better than the first?
Hummmm
And interpretation......
After more inquiries about my 'pump or not to pump the seepage pit'.....one source said,
this would reduce percolation due to the loss of the weight of the water.
In other words, the hydraulic pressure, exerted by the sheer weight of water at about 8 lbs/gallon, helps to push fluid into the soil. His theory is the last half of a pit lasts longer and works better than the first half due to all this weight.
That being said, pits still fill up and fail after enough time.
But, does the last half percolate better than the first?
Hummmm
