Another Septic System cost/alternatives thread

Finnster · Jul 16, 2013

My septic is getting old and performs marginally in the winter when the ground is wet and saturated. Summer months have been fine.

We have a 40 yo underground system. 1000 gal 1-stage concrete tank feeding a leach field of perf pipe buried in gravel. Fair amount of sludge build up. We have poor draining clay soil as well. Test pits showed value of 17 to 21 IIRC. The current system is deep also. The Dbox was about 4-5 ft deep.

We've been in the house a year, and this was known as part of the purchase.

A septic company inspected/designed and permitted a sandmound system w/ new 1500 gal poly tank, but the quotes to build the system are around $25K. Seems way higher than many others I've seen here. The sand mound will require a pump in the tank. Old tank will be abandoned and filled with gravel.

Is this more normal to my area (SE PA), a completely off base #, or what? I think this was for 700gal/day or so. (5 bdrm house.)

Lastly, I guess below grade options are off the table due to perk tests and the water table height.

I really do not want to shell out that sort of $$ for a pooper, get a giant useless mound in my yard, and be on the hook for a generator/backup to run the pump in case of power failure.

"Repair" of the system is not possible through official channels if you know what I mean. Seems like digging up a line or two, or adding a new line would be preferrable.

Any thoughts about just updating the tank to a multi-stage tank to cut down on the passed solids?

Thanks

dmccarty · Jul 16, 2013

The soil in my area stinks for perking which, ironically, is why we were able to buy our land. The land did not perk well enough for a subdivision but it perked well enough for us to get our house. However, we had to escalate the incompetent at best, local inspector to the state regarding his perk evaluation. I learned quite a bit ASAP about the state perc regulations. We had to buy our land, which cost more than the house we were living in, without a perc permit and with the county denying the permit.

The NC extension office has quite a bit of information on septic systems. Somewhere online I found the NC septic regulation which is quite detailed. It actually has specifications for building an outhouse. This information was critical in our buying of our land because it allowed me to evaluate the competence of the local inspector and told me what I could do about the idiot.

In NC, tanks should be designed so they have enough capacity to last a few days without needing to be pumped.

Once you know the regulations and the specifications its not too hard to figure out if the contractor's price is fair.

Later,
Dan

teejk · Jul 16, 2013

That cost seems high. Here in Wisconsin (very tough standards) a new conventional below grade system cost me about $7,000 3 years ago which by code included a 3 chamber 1,500 gal tank (sized for a 4 BR house), pump/alarm and drain field. I hear that mound systems can be a little pricier because they require a special sand but I can't believe it is that much more. Here I think we also have a "at grade" option which cost wise is supposed to be in the middle.

plowking · Jul 16, 2013

We have had pretty good luck by uncovering the top or end of leachfield and letting it sit open to allow the air flow to clean the contaminated soil. Also jetting the leachlines and maybe adding an oxidizer may help the system. Any system that has more then 18 inches of soil on top should have the leachfield and or distribution box vented. Water softener discharge should be seperated from septic,the discharge of salt and minerals is bad for system. I find newer technology leachfields (enviro,eljen,geoflow) have more trouble if they aren't vented and the fabric around the system gets easily clogged. plowking

doxford jim · Jul 16, 2013

Don't know what your land situation is, but If you have the land (over say 10 acres) I would consider a septic lagoon. It sound terrible but is really not too bad. The liquid evaporates off and the lagoon is sized to the house (number of bedrooms).
I had a sand mound installed (cost $22,000) and the whole system failed within eight months. As I am on clay soil and the clay supported a lagoon, the replacement system is a lagoon and it works well.
I won't go into the details of my complete fuster cluck, but the lagoon is relatively problem free - so far (six years).
Check out your options - if you have the land, don't use a sand mound.
HTH
Jim

MapleLeafFarmer · Jul 16, 2013

I just put one in. Pressurized sand mound. 120' chambers $17 each, 2 chamber poly tank at $1400, 4/10 hp high head pump, installed it myself with my Kubota B2620.

My biggest cost was having hauled in the graded C-33 sand for the mound and sandy loam for the cover as I live +1 hour from the nearest village that has this material available. This is spec'ed material required to pass inspection on a new system in my area.

1600 sq foot total area and sand mound itself was 10'*42' utilizing 3 lines. Holes 3/16" spaced 4' apart gave me a 20" squirt test.

Total cost was 40% what the local contractors were quoting.

total material cost came in at $6,000 including pvc/abs/tank/pump, hauled in material etc....

My soil tested out at 96.4% sand at 3' depth

Pete Judd · Jul 17, 2013

When we put the in-laws in in 95 the cost of a "mound system" was about 10K. When we sold the 5 ac parcel a few years ago the cost of their system was about 15K. We are grand fathered in on a gravity system and I figured it will last to my last days.

Finnster · Jul 17, 2013

Thanks for all the replys.

boakley said:
I just put one in. Pressurized sand mound. 120' chambers $17 each, 2 chamber poly tank at $1400, 4/10 hp high head pump, installed it myself with my Kubota B2620.

My biggest cost was having hauled in the graded C-33 sand for the mound and sandy loam for the cover as I live +1 hour from the nearest village that has this material available. This is spec'ed material required to pass inspection on a new system in my area.

1600 sq foot total area and sand mound itself was 10'*42' utilizing 3 lines. Holes 3/16" spaced 4' apart gave me a 20" squirt test.

Total cost was 40% what the local contractors were quoting.

total material cost came in at $6,000 including pvc/abs/tank/pump, hauled in material etc....

My soil tested out at 96.4% sand at 3' depth

How would you rate the construction difficulty? Looking at my plans, it looks rather straightforward, just a bit time-consuming based on all the sand to move, etc. Your system seems spec'd close to mine, tho mine might be a bit larger based on the poor soil drainage here. I have to look at the plans again, but I'm pretty sure its longer than 42'.

Looked absurdly big when it was staked out for permitting approval.

Finnster · Jul 17, 2013

So the preferred course of action is restoring my underground current system.

I talked a local company, and they recc'd having the system hydrojetted (fancy pressure wash and backflush) to clean out the sludge/solids, then seeded with bacteria for bioremidiation of the remainder.
Total cost should be ~$2000. I can dig up my own Dbox for some savings.

My FIL had the bioremediation done on a 50yo failing leachfield with great resorts. I'd much prefer to go this route and save my system. Has anyone else had this done? Comments?

plowking · Jul 17, 2013

Finnster said:
So the preferred course of action is restoring my underground current system.

I talked a local company, and they recc'd having the system hydrojetted (fancy pressure wash and backflush) to clean out the sludge/solids, then seeded with bacteria for bioremidiation of the remainder.
Total cost should be ~$2000. I can dig up my own Dbox for some savings.

My FIL had the bioremediation done on a 50yo failing leachfield with great resorts. I'd much prefer to go this route and save my system. Has anyone else had this done? Comments?

Sounds good to me but I would still add venting to the end of leachlines and a shorter vent at the box. Lack of oxygen is a big problem that causes the leachfield to turn anaerobic from aerobic. plowking