Click on See Comment # in the frame to the left to view the corresponding comment.
Comment 1.
Double-washed stone preferred to reduce
suspended solids and potential for clogging.
Comment 2.
This is to supply organic
material, other sources can be used. Mulch is preferred because it
can be obtained on site and it is relatively stable. Alternatives include
compost and peat moss.
Comment 3.
Avoid high clay content soils.
They tend to create hard pans and clumps that reduce filtration and storage.
Comment 4.
Allow sufficient time for testing.
Suggest certified source or laboratory to reduce mobilization time and
construction delays.
Comment 5.
Use of flexible slotted HDPE is
preferred. Large openings on PVC pipe may allow sediments and
larger materials to migrate into system.
Comment 6.
Equipment will compact bottom,
reducing any infiltration capacity. The structure of the soil and pore
space can be restored by aeration/rototill.
Comment 7.
Wrapping pipe in silt sock or textile is
discouraged. Smaller silt particle sizes may clog these
systems.
Comment 8.
The screw cap is used to control the
rate of discharge. Larger underdrains and outlet structures.
Openings in the orifice can be used to control rate. Cap should be
removable for cleaning.
Comment 9.
Make sure E&S is in place at outfall.
Comment 10.
This should be done immediately after
grading to reduce potential of any silt accumulation on surface.
Comment 11.
It is suggested that a biodegradable berm
constructed on a permeable geotextile tube filled with the bioretention soil
and seedstock be left around the perimeter to filter sediment after
construction. Other alternatives such as biologs are acceptable. Sediment loads can still be significant, even after
permanent vegetation cover is established. These berms can be removed
after the maintenance period.