04-Septic Excavation
Excavation
Per
your approved permit please follow installation instructions:
All septic tanks must be
installed according to state and/or local regulations, which supersede the
manufacturer’s installation instructions. If unsure of the installation
requirements for a specific site, see your permit, and /or contact the health
department or permitting authority. All drainage must work correctly since it
must pass a final inspection.
Consider including some grey
water going into your septic tank, so that there is enough liquid to process
solids.
Excavation
(Excavate before delivery of concrete septic tank so that you are ready for the
OSR Crane Operator or your vendor):
The site
should be excavated properly and the base
leveled prior to setting the tank. (Inspector
will check that the septic tank is level).
The depth
of tank correlates to the pipe coming out of your house. The top of the tank needs to be at one foot below the ground surface.
The length
and width of the excavation should provide adequate space to allow for proper
compaction and backfilling, and most importantly, provide a safe working
environment for the crew. It’s
so much easier to place the tank in a larger hole!
You will
need rock no bigger than 2” to backfill in the front of the septic tank of
inlet area.
The heel of
the bucket can be used to compact the excavation bottom prior to setting the
tank.
Setting
the Septic Tank: The base of the septic tank should be carefully lowered into the
excavation. Check to ensure the tank is
level in both directions and adjust the tank as needed.
Leach /Drain Field
& Pipe. Follow
permit instructions for trenching the leach /drain field, and installing pipe.
Inspection. Leave your system
exposed until after your final inspection. Call Cody Griffith in Nephi Central
Public Health to arrange an appointment for your final inspection. Be sure to
be on your lot during your final.
After inspection: After inspection,
you must first cover the drainage pipe with straw or felt or landscaping weed
barrier as a temporary barrier so that sand and dust does not get into the perforated
pipe while you are backfilling the drain field.
Native soil in
lifts of 12 inches on all sides of the tank. Compact the soil with the heel of
the bucket in 12” lifts and by walking-in the soil around the tank.
Do not cover the top of the tank until
after final inspection. The inspector will want to ensure that the
tank is not leaking.
Install inlet and
outlet tees at the designated locations, and also risers should be installed
per plan. Install septic drain fields or leach fields /leach drains.
After Final Inspection – Cover the
septic tank: Once the septic tank is properly backfilled and compacted, place
topsoil up to the final grade and provide positive drainage away from the
septic tank. Additionally, the site should be seeded to minimize erosion and
divert surface water.