Information about “Best Available Technology” reduced-nitrogen septic systems
potomacAvenue
| Posted in General Questions on
I’m building in Maryland, where the state just passed a law requiring homeowners to install “Best Availalble Technology” septic systems. The State has approved a few models – Singulair TNT, Hoot BNR, Advantex and a few others. Because these technologies don’t seem to be widely used and they’re kind of new (which concerns me), I’m having a hard time finding objective informaiton about which one to choose.
Does anyone know of a source for good unbiased information or comparisons on these types of septic systems?
Thanks
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Replies
What would you like to know about these systems? I would not use MDE's reduction numbers, because of the way they used to calculate them. I would use their NSF numbers. All of the systems on the list reduce BOD's, TSS's & TN. I like the Norweco Singulair TNT for these reasons :
1) cost ( the lowest purchase price)
2) It is gravity flow ( when the power goes out it will still work)
3) Maintenance ( easy to maintain)
4) Repair ( you do not have to dig up the tank to repair any part of the system)
5) Reliability ( only one moving part that has a limited limetime warranty)
6) Installation cost
As far as finding an unbiased source I don't know of any, but you can contact installers in your area to ask them which ones they like and why. I would not ask the Manufacture's for a list of customers, because they are only going to give a list of the ones they are not having problems with. These systems have been in use for a long time, so there is plenty of information on them. One thing to remember after 5 years from installation you are required by MDE to have a maintenance contract with an MDE certified maintenance provider.
Thanks Wyatt - After spending a couple of weeks looking around, I had pretty much determined the same thing - the gravity flow and minimal amount of moving parts sold me on the Singulair.
Colby,
I'm impressed by the Enviro-flow 'Nu-water" system. they are available with either concrete of poly tanks, can be used in gravity flow or with a lift pump. I don' t know if they are on the approved list, but they should be.
Jerry,
Do you have a link where they are available in America? The only info I could find on them is they are large wastewater treatment systems available in SE Asia. They are not on MDE's BAT list & what we are talking about are single residental systems.
Wyatt,
Their web site says they are a Mississippi company. Definitely a single family system. Here is a link.
http://www.enviro-flo.net/manualpage.html
Jerry, Enviro-Flo's tank design copies Norweco & Jet, but not their process. While this system should
reduce the TSS's & BOD's it's total nitrogen reduction is probably low. To get good Nitrogen reduction
the waste needs to sit in a anaerobic state then go to a aerobic state. This system does not have a
anaerobic state. To get on MDE's approved list the system must reduce the total nitrogen content to below 30mg/L
Wyatt,
The Nu Water system has an anerobic chamber followed by aerobic with recirculation of some of the aerobic sludge back into the anerobic chamber. Enviro Flow versions do not include the recirculation, which the Nu-Water does with an air bubble pump. My understanding is that anerobic then aerobic does some nitrogen reduction but adding recirculation adds even more.