Rainstore
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Storm Drainage Detention & Exfiltration with Geotextile Fabric
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A.
When the side backfill compaction is complete, the third layer of geogrid is ready
for installation. The final layer of geogrid must extend beyond all sides of the
Rainstore
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installation at least three feet. The third layer helps dissipate the load of
traffic. Have two workers unroll the geogrid. Make sure the seams overlap at least
12 inches.
5.12 Top Backfill:
A.
Add the top layer of backfill material over the geogrid material. The backfill must
be compacted in six inch high lifts to 95% proctor density. Use a walk behind
roller for small installations.
B.
For installations with an area of 1,000 square feet or more, a light drivable roller
such as the Bomag 125 D-4 that weighs 3,125 kgs (6890 lbs) or a compacter of
similar weight may be used for compaction after the first six inches of fill material
have been installed.
C.
Fill material should measure 12 inches minimum and 36 inches maximum. To
ensure the backfill is properly compacted, have a Geotechnical Engineer test the
fill density on site.
5.13 Surface Material:
A.
Once compaction is complete, cover material may be placed. Landscaping
materials such as grass, or shallow root shrubs may be planted. For parking lot
applications: Grasspave2, Gravelpave2, asphalt, concrete or other pavement may
be installed.
Rev 10/2011
