The inspection of
amended soils for potential problem areas is warranted from time to time
to ensure that the intended characteristics are maintained. If left
undisturbed, amended soils should continue to provide stormwater
management benefits such as a reduction in peak storm flows, increased
infiltration and improved water quality. In some jurisdictions across
the country, soil amendments may be inspected as part of the sediment
control plan for a site, usually done upon site completion. Information
requested for a post-construction inspection may include:
Infiltration test
of amended soils.
Site size, and
volume and depth of soils that have been amended.
Compost type,
including its maturity rating and parent material.
Composition of
compost, including nutrients utilized and organic content rating.
The criteria for
inspection of amended soils on a routine basis should include any
aspect that may have the potential to affect the infiltration
capacity, aeration and organic content of them. Inspection points
should include any areas where potential concerns appear obvious.
Typical post construction areas of possible concern include:
Areas subject
to compaction, such as soils in high traffic areas like foot paths
and playing fields.
Hydric or
waterlogged soils, where the maximum infiltration capacity has
already been achieved.
Poor cover
conditions, where cover conditions are far from optimal and
vegetation is sparse, or rills and small gullies have started to
form.
Increased
development, causing a disturbance of the already amended soils
along with uneven water flow patterns due to restricted
permeability.
A decrease in
organic content, usually visible by poor cover conditions and
spotty growth.
In addition, a
routine soil infiltration rate analysis of amended soils in
potential problem areas is recommended.
In some cases,
once soil amendments have been established, added support to keep
them and the grass growing on them in place will be required,
especially along steep slopes. A number of
plastic polyethylene mesh products have
been developed in order to help improve the capabilities of grassed
areas to withstand heavy and/or intensive wear and to help slow down
potential erosion.1 These products include
anything from thinplastic mesh
elements installed directly at the root zone to more heavy-duty (up
to 50mm thick) interlocking extruded polyethylene mesh for higher
traffic areas, including occasional vehicle traffic. These support
structures can be laid on existing grassed areas or seed can be sown
over them. They are easily installed on existing or recently
amended soil and provide a stable surface capable of withstanding
higher loads. As the planted grass develops the grass intertwines
with the mesh to provide a completely natural appearance and near
permanent protection against wear.
The benefits of utilizing plastic mesh
products along with soil amendments include: