property:development:services:septic:Home

If doing it oneself: * Instructions:

• https://www.youtube.com/watch?v=ubQ3IqXoqsY

* Basic info:

• Inlet pipe must be higher than outlet.

* Risks:

• When you pump out, you are removing the water, so they cave in.
• IBC's are not recommended.

* Procure:

• 2+ IBCs. Non-Food grade (because cheaper) (https://rainharvestproducts.nz/product-category/ibc-1000-litre-tanks/)
• 4“ (102mm) drill holesaw (https://www.bunnings.co.nz/promark-16-piece-holesaw-set_p0695122)
• PVC 100mm (https://www.bunnings.co.nz/holman-100mm-x-3m-pvc-dwv-pipe_p4770345)
• 4 pipe connectors to connect pipes to IBC.
• 1 pipe lid.
• 1 90 degree pipe elbow down. No. Get a T piece on it. Vertical.
• solvent
  • Bricks
  • Sand
  • Cement
  • Aggregates
  • Timber for
  • Steel reinforcement
  • Hard Core
  • PVC pipes
  • 1xPipe Bends
  • 2xAll Hub Sanitary Tee

* Prep:

• Pro Tip: To make it easier to work above ground, put a box or something that is same height, to offset boxes on ground…
• Drill 4” (102) in corner of TOP of Bottom tank (intake).
• Drill 4“ (102 in center of TOP of Top Tank (outake).
• Drill 4” (102 near top of SIDE of Bottom tank (intake). Debur, etc.
• Drill every 2“/5cm in straight line down 2 lengths of 6m drainage pvc.

* Follow instructions:

• https://www.youtube.com/watch?v=VfHh5Y052nI
• Dig hole:
  • width of IBCs
  • with approx. 1' step difference of floor under each tank (to cascade down).
    • Height is determined by allowing pipe to connect pipes without having to cut out section from 2nd crossbar of upper IBC…
• …if you didn't get the offset right, cut out piece mentioned above…
• Lock in box boxes to cage. So they don't float up?
• Dig trench. Save sod on side.
• Put in 2” gravel bed.
• This will be to support drainage field tube.
• Cover pipes with cardboard?
• Cover cardboard with dirt.
• Install gas exhaust Pipe with lid in center hole of top IBC
• Connect elbow to top of bottom tank.
• Connect drain pipes 2x Pipe Connector
• …
• Fill bottom tank with water, till it overflows, and flows into second tank.

But comments say it's wrong. First tank is to be higher… * Terms:

• Grinder/Macerator: Can be used to make the system a bit safer in that it can grind up solids. Careful though: tampons, even ground, can make it to drainage field and block there.
• Inlet: 100mm entry point to first of 2 or 3 tanks.
• Sludge: what settles to the bottom of the first tank.
• Scum: (grease, wipes, tampons, etc.) what rises up to float in the first tank.
• Anaerobic bacteria: the first tank uses anaerobic bacteria to break down sludge.
• Effluent:
• Baffle: separates the first chamber from second, to minimise disturbance to settled solids.
• Aerobic bacteria
• Outlet
• Distribution box. Connects Outlet to Leach Field.
• Leach/Draing field: network of perforated piples laid in trenches filled with gravel/aggregate permitting percolation into soil.
• Soil absorption. Soil acts as a natural filter, providing additional treatment as effluent percolates. Microorganisms in soil break down contaminants.
• Vegetative cover: planting grass/other over leach field helps absorb excess moisture, and provides additional treatment.
• Use anearobic process unless required to go to aerobic solution.
• Bury it deeper to stay warm in winter and not slow down - which leads to requiring pump out more often.
• Put a “bull run Y valve” before drainage field so that later can add another field if first clogs up.

* Basics:

• Come in 2 tanks or 3 tanks
• Don't want it to leak at all, ever. So concrete or appropriate thick fiberglass or polyethylene.
• Don't want anything solid in effluent before discharge via seepage field.
• 3 tanks is better than 2 tank systems. They improve breakdown and pathogen removal, as well as better effluent quality before discharge.

* Design of tanks:

• First tank: it's a settling tank, for 'primary treatment', which is simply solids to sink to the bottom, and marginal/partial decomposition of organic matter via anaerobic bacteria,
• Second tank: treated effluent, minus solids, moves through a baffle, to the second chamber. Additional settling of solids occurs.
• Third tank. Additional settling.

* Note: Aerobic bacteria are not part of the traditional 3 tank system. * Aerobic systems are useful when specific targets (near water, etc.) are required as effluent is of higher quality. Have higher maintenance needs and cost. * Aerators are not used in traditional systems.

• But in an aerated system air is pulled in and released as fine bubbles released via a diffuser into the first and third tank, to make it work by aerobic (versus anearobic) bacteria.