leech field

[Highbeam]

The anaerobic decomposition takes place in the septic tank and the aerobic decomposition takes place within the soil matrix as the effluent soaks into the ground.

The septic tank also provides the primary treatment in that it allows residence time for the sludge to sink and the scum to rise.

DKinWA, I though about my above comment about you being a designer and what I was getting at is that you and I could get some work done together if we were both looking for more.

 

[HomeBrew2]

THANKS for the link! I too spent time yesterday trying to find support docs. I think I remember the EPA guide from some years ago but couldn't find it. For those that would like a PDF here's a link to the directory that you can download chapters, etc of the multi-MB doc: PDF file directory
Cheers!

 

[HomeBrew2]

Oh, this seems to be the complete doc ... 20MB download

 

[HomeBrew2]

Cool!, got it downloaded ... 1.5 hours on dialup ... I'm single and don't answer the phone anyway so who cares /forums/images/graemlins/wink.gif
I browsed Ch. 4 and read Sec. 4.4. I found other sections in Ch. 4, mostly regarding interface with the ground water, to give references and be specific as to consequences if certain guidelines were not followed. In Sec. 4.4, I found only the word "should", with no references, applied to the maximum cover. Sec. 4.4[.0] indicates "<2'" of cover "should be used; Sec. 4.4.3 indicates "3' to 4'" "should" be the maxium cover. Again, no scientific references are cited, however, soil conditions are cited as a variable.
Just curious ... are the above references worthy of advising someone that he may be endangering the health of himself or his neighbors by adding some fill over a portion of his leach field to add to his lawn area, which is a preferred, oxygen enhancing, use above a leach field.
Again, thanks for the link to the document. I certainly appreciate having it in my library. Cheers!

 

[8561]

Guys - I'm not qualified and am not trying to say what will and won't work. What I can tell you is they exist, and I can certainly tell you that the septic system inspection process around here is exhaustive to say the least. I know first hand how difficult they can be inspecting residential systems, I can only assume they are tougher in a commercial application. I've built a couple of houses and my father has done several more so I have seen the pre-approvals, and the interim and final inspections our state completes. Beyond that, I don't know what to tell you.

I am curious about the well comment. If a well is constructed so that the steel well casing is pounded and sealed into bedrock (in my case about 65 feet down), how can septic effluent, filtered that far down, damage my well. That in combination with the fact that a well has a radius around it of 75' into which the septic system cannot be constructed, it seems unlikely anything of this nature would adversely impact a well. I'm not picking a fight, I just don't understand (honest question).

 

[Egon]

Your well draws water from an aquifer. This aquifer is recharged from surface water. Some one many miles away can affect your water quality just given time.

Egon

 

[Egon]

10

Anerobic = no oxygen

areobic = oxygen

Each section of the septic system uses a different system.

Egon /forums/images/graemlins/grin.gif

 

[DKinWA]

I'm looking to quit my day job and go full time with the dirt work, but I'm going to wait till we finish our house. With a little luck, I hope to be in it by April of 06'. Once that's done, I'll definitely be looking for more work and tag teaming some projects might work quite well. There's so much development going on in your area it's unbelievable. I was in your neck of the woods a few months ago and even Orting is growing like crazy!

Here's one more link you might find interesting WOSSA

 

[8561]

And this is all made good if the leach field is close enough to the surface so as to allow some breathing?

I was under the impression that the sand in the field as well as the earth the water passes through act a filtering device as it heads for the aquifer. How does adding some access to air near the surface change the make-up of this material? It would seem like 10 inches of sand cover and 6 or 8 inches of topsoil would severely limit the air access to or from the field. Mine has no "candy cane" breathing pipe by design.

 

[DKinWA]

</font><font color="blue" class="small">( ... 1.5 hours on dialup ... )</font> Ouch!!

Here's another site with some good information Washington Dept. of Health
I'll try to find some of the scientific literature you're after, but I probably won't have time till this weekend. I'm a biologist first and contractor second, and I know I've got some of the info you're after somewhere /forums/images/graemlins/confused.gif

 

[HomeBrew2]

I sure do appreciate your interest in getting quotable information out to those of us interested in this topic. It seems as though we have lost some of the other respondants when documentable facts became a part of the conversation.
I do have to admit that my interest in this thread was nill until comments were made regarding a possible contribution to the detrimental health of one's family and/or neighbors if some more fill was put on a leach field. A leach field that is in an area unknown to most contributors to this thread. And, after reviewing a Fed doc, there seems to be little basis for previous claims of impending calimity, I find no need to pursue further links from Washington, a state far removed from the original poster. However, I do hope to hear of solid evidence of how a man that wants to add some fill to a portion of his leach field is, in fact, going to negatively impact the health of himself, his family, and/or his neighbors. But, then again, it's just me wound up about this ... I'll pull a lovely homebrew and forget about the whole affair tomorrow.
Cheers, but thanks again for the link to the doc /forums/images/graemlins/smile.gif

 

[SCB]

DKinWA,
What part of GH are you in. I grew up in monte and lived in aberdeen for a while. My family is still down there. I'll be back down there in a few months to do a little hunting. I sure miss that little corner of the world.

 

[Egon]

The aerobic action in the leach field involves little buggies that futher help clean up the water. Covering vegetation also helps with transpiration of the effluent. Sewage treatment plants may spray the effluent in the air for additional purification..

Ground may act as a filter but still allow pathogens to pass on.

Egon /forums/images/graemlins/grin.gif

 

[DKinWA]

I was born in Hoquiam and lived there for about 22 years and then moved to the Elma area. There's a surpising difference in weather and we get a lot more growing season than the aberdeen and hoquiam area. It's amazing how many people knock the harbor, but it really is a nice area. Within an hour you can be at the beach or in a tropical rainforest and if you make it two hours, your options really expand.

 

[Tom_H]

This is very interesting. Where I live, we have 1'-4' of very dense clay. Below the clay is a 3'-7' layer of silica cemented durapan, a type of hardpan that is like concrete and is totally water impermeable. Therefore, the soil will not perc.

Now up in the Sierra, where houses sit right on granite, they have to build greenhouses with huge sandboxes inside. This makes a solar evaporative leech field.

Here in the Central Valley we have a different solution. We go down, straight down and way down. Below the hardpan is a layer of sand, another layer of hardpan, another layer of sand. My wastewater goes from the septic tank to a distribution box, to 5 dry wells. Each dry well is 3' dia. and 30' deep. The hole is filled with 8" to 12" dia. rounded granite river rocks. The hole is tightly capped (at the hardpan level) with a concrete disc 3' dia. and 1' thick, to prevent soil from falling into the cavities between the rocks.

This system is obviously deeper than any leech field and far more sealed off from atmospheric oxygen at the surface than any leech field.

The sand layers provide a place for my wastewater to go. Perhaps some abovementioned maximum leech field depths were not so that oxygen could flow downwards, but so that water vapor could transpoevaporate upwards. We do have minimum distances between wells and septic and well depths are around 300', far below the septic level and separated by layers of claypan.

What you need to do is ask the experts in your region. Call the same city or county agency that inspects septic systems for new construction and ask what the local codes are. That way you will know you are doing the right thing and will not be taking any risks of getting into trouble.

 

[GabeTX]

Interesting--how does the cost of that kind of system (with the 3' x 30' drywells) compare to the cost of an aerobic system with sprinklers? That's all we're allowed to use out here in Denton County, Texas....

 

[Tom_H]

When I put it in 16 years ago, excavation, tank, boxes, 5 dry wells, everything was a bit under $5000.

They use a giant auger to drill the holes, then dump the rocks right in out of a dump truck. The rocks come from streams in the Sierra Nevada maybe 60 miles away.

 

[Jagmandave]

Wish I could get by that cheaply! I've been quoted $18 - $20K for a mound system for a house with three bedrooms and 2 1/2 baths, but that's only if they don't hit rock (which, of course, they will)