DIY Septic System

[davo727]

Hey Steverino: Thanks for posting the pics and info.

What depth range does infiltrator want for the base level of the chambers?

Thanks, Dave

 

[dfkrug]

What depth range does infiltrator want for the base level of the chambers?

I have Infiltrator Systems chambers installed for my system, and they are
six feet deep. My system is engineered and inspected, and on a 40%
slope. Total length is 300 feet on 4 terraces that had to be cut in the
hillside using a crawler TLB.

 

[davo727]

Thanks, Why did you need 300 feet? A huge house? Steverino has 120 feet.

I also found on the infiltrator site where they show the chambers in a 2 foot wide and 2 foot deep trench. Chamber is 12 in high so 12 in of fill over the top.

 

[dfkrug]

Thanks, Why did you need 300 feet? A huge house? Steverino has 120 feet.

That is the smallest size allowed in this county for houses of 4 bedrooms or
less. Septic ordinance keeps leach fields very large (regardless of what
kind of technology you use) to restrict what parcels can be developed. I had
to get special permission from the Director of Env Health to use Infiltrator in
my pump-up system.

 

[Steverino]

Hey Steverino: Thanks for posting the pics and info.

What depth range does infiltrator want for the base level of the chambers?

Thanks, Dave

Dave, I have always been told to keep the entire septic system as close to the surface as possible. Here in Connecticut the frost line is 18 inches down. So when I installed the tank that was my calculation for the top of the tank. I then had to factor in a pitch back to the house of 1 quarter inch per foot to keep the sewer pipe below the frost line so that added an additional 4 inches. But because the entrance to the tank is 4 inches below the top that washes out and the tank is just below the frost line. The outlet of the tank to the leach field is perhaps 6 inches below the top of the tank, so starting from that point, with a gravity system, I have a quarter inch per foot downward pitch on all the lines to the inlet of the infiltrator. The infiltrators are all installed on level ground so depending upon which infiltrator you use you would measure down from the inlet to the required depth for the infiltrators to set flat. So if you go 20 feet from the outlet of the tank you would drop 5 inches and if the infiltrator is 24 inches from the inlet to the base, you would add 5inch drop + 24 to bottom of infiltrator + 2 inch offset for the distribution boxes + 6 inches to top of tank and dig to a depth of 37 inches below the top of the tank. I hope I have explained it adequately.

 

[boxygen]

Well, I've started on my septic system. Two weekends ago I dug the hole for the new tank. I finished prepping the hole after work and Last Friday, I set a new tank in the hole and got it hooked up.

I needed an 11 degree PVC elbow since the tank was so close to the house,it was the only answer. I found one at the pipe supply store in Portland, schedule 80 it was $45 for one
I borrowed my neighbors 6' tiller and tilled about a 50' square area in my side yard where the leachfield will go and the driveway gets larger. Its nice old established grass and rich loam. I have about 30-40 CY should be plenty.

I got to get out the old Holder AG3 to do some tilling action

I started excavating the leach bed. This part took me a lot longer than I thought it would. I think it took me 10 hours or so. I would dig all the way across in abou a 6' strip and then use the loader to move the spoils. I used the spoils to build up on one end of the field since the bottom of stone bed was pretty much at the grade that I started at. That worked out just about perfectly.

Since the new tank was now hooked up, I could now discontinue the old tank. I dug it up to find out what it actually was. The top turned out to be a piece of round granite about six feet indiameter and four inches thick with a hole in the middle. Looks to be an old well cover. The guy that pumped the tank said it was one of the worst he has ever seen It looked like it had never been pumped. The solids in the tank were like asphalt, he couldnt get them all out but got enough out to cave it in on itself. Luckily it was built out of concrete block and broke up easily. It was in surprisingly good shape but I wont miss it

I've been on borrowed time this week with an empty tank filling up with no where to go when it does get filled. Looks like we lucked out. My stone for the leachbed was delivered today and I started putting in a few yards when I got home from work this evening. I will be working on it a little this weekend and I have next week off from work so I should be able to finish all of it, if everything goes ok.

 

[boxygen]

Photos

 

[atgreene]

Nice job. Is the tank closer than 8' from the house? Code is 8' minimum distance, may want to be creative when the inspctor comes if it's within 8'.

 

[boxygen]

Thanks AT. Yes, in fact its about 4' from the house. Thats about the only place it could go, the site evaluator put it there and I pulled the permit with that plan. The inspector has already seen it also. I have an old non-conforming lot and a lot of the current setbacks just dont work with my lot. For example, my well is 64' from the leachfield, and we all know its supposed to be 100. I had to get a variance for that. I guess with a variance you can really go down to 50-60'. When I built my garage I asked what the setbacks were. I think it was 75' from the road. I really wanted it a little closer and I asked if I should file for a variance. Once he remembered my non conforming lot he said I could build as close as the current least restrictive building. Well my was built in the 50's on an old farmhouse foundation, about 20 feet from the road, I could have built my garage that close if i wanted to! Also, the building inspector is a good guy and is happy that I'm taking the steps to build a modern system because he knows that the old system was suspect long before I bought the house. I'll post more photos this week. I got most of my stone in this morning, but had to go to a wedding this afternoon. Oh! I forgot one part of this project that is related but I dont think I took any pictures. before I started any of this I ran conduit for underground power and communications because the only place they could go were under the leach field. Its never just one simple project its a bunch of interconnected project. This septic system is really a driveway widening/underground utilities/driveway extension/walkway moving/septic system. I've got to put my butt in gear this week so I don't miss woodsmens day at Fryeburg Fair, right atgreene?

 

[boxygen]

I finished the project today. I got the stone and Pipe in and Inspected on Monday. Tuesday I topped it with sand and rough graded ready for loam. Wednesday I got all the loam on the leach field and side yard. Thursday I switched gears a little bit and did some regrading of the driveway and behind the garage since the old tank is gone. I used some sand I had to bring up the grade and ease the slope and then loamed it. I also went a little crazy with the 6' tiller and tilled a bunch of my lawn to smooth it up. I had dug a lot of rocks that left the lawn pretty lumpy and hard to mow. By the way my 2415 Mahindra should have no business anywhere near a 6' PTO tiller on paper but actually handles it ok. It will chew through sod without lugging if you go slow enough, made possible by the HST. THe tractor is advertised as a 24 HP but they use the same engine in the 28 HP model rated at a different RPM. Today I added 20 yards of gravel to the driveway to make it wider and longer. I also finished moving the walkway and I seeded and put hay on the leachfield and behind the garage. I put about 60 hours on the tractor in the last month and I might treat it to a wash tomorrow. I did have two major breakdowns along the way- the hydraulic fitting on the backhoe outrigger loosened up which required TWO wrenches to tighten! AND I lost a grease fitting on the lower pin of the loader. I should have put it on the trailer and taken it back to the dealer right then and there
Time to decide on the next project....