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4.
Remove any vegetation you will want to save and
replace when the project is finished. Small plants,
even turf grasses, can be removed and stored for
replanting with proper care.
5.
If desired, remove the topsoil to a depth of 10–20
centimeter (3.9–7.9 in), depending on depth of
the topsoil layer. Store the topsoil away from other
spoil material to avoid contamination. Ensure that
the topsoil heap does not exceed 1 - 1.5 m in
height to avoid compaction.
6.
Begin the digging. Line your workers or equipment
up with the ditch line, be aware of their location at
all times and start to dig. Be careful to observe soil
conditions so that the trench embankments do not
give way, allowing them to cave in.
7.
Dig your first section to the depth you have
decided is deep enough to serve the purpose of
the trench, or if the trench needs to be benched, to
the depth of the first bench.
8.
Throw, or cast, the spoil (the removed soil) as far
from the trench as possible, so it will not get in your
way while doing work in the trench. This will also
prevent the spoil from caving in the trench sides).
9.
Move along the length of your trench as each
section is excavated to the required depth.
Checking the depth.
10.
Continue digging until the whole trench is
complete. Recheck the depth of the trench, check
the sides for stability.
11.
When work in the trench is complete, backfill the
trench. You may want to tamp to pack the soil as
it is replaced in the trench. For deep trenches,
backfilling in lifts (layers), and compacting the
material as it is placed will reduce the amount
of settling that will occur after the project is
completed.
12.
Replace topsoil as soon as all the spoil has been
back-filled. This will ensure fertile soil and easy
re vegetation without having to resort to costly
fertilizers.
Pile spoil
away from
the edge of
the trench
Trenching
5.2.4 DIGGING ON SLOPES
Use extreme caution when excavating on a slope:
•
If the ground is soft use pads or timbers under the
stabilizers feet.
•
Do not attempt to begin excavating on a slope
while the backhoe is positioned on an angle,
danger of tip over is much greater since the center
of gravity moves to the down side of the backhoe.
Build up one side or dig into the slope to create a
stable, level area to work on.
•
Avoid swinging the boom to the downside of
the hill, danger of tip over is much greater since
the center of gravity moves to the further to the
downside of the backhoe as swing increases.
•
Level the backhoe using the stabilizers so the
center of gravity is closer to the middle of the
backhoe, making the backhoe more stable during
excavating (ensure all four wheels are touching the
ground).
•
Always swing the boom upside the slope, but if
swing downside is required, do so with extreme
caution and swing only as far as necessary to
dump the bucket.
Safe work
