20061347 Ver 1_Emails_20070404

Howard Farms 06-1347
Subject: Howard Farms 06-1347
From: Annette Lucas <[e-mail]>
Date: Wed, 04 Apr 2007 14:02:19 -0400
To: Ian McMillan <[e-mail]>
Ian,
This one needs to go on hold. Bullets:
With regard to the bioretention areas, the following items need to be addressed in
the resubmittal:
- Add a specification for stakes for the trees.
- Add a planting detail (approximately one-half the root ball should be placed above
the surface of the planting soil).
- Add a pretreatment system for removing sediment from the stormwater before it
enters the bioretention area.
- The depth to ground water must be provided in order for DWQ to approve the
bioretention systems. Please provide appropriate documentation of this.
- Modify the specifications for the planing soils; the currently proposed mix that
includes 10 to 25 percent clay will cause clogging. The NCSU Department of
Biological and Agricultural Engineering has a recommendation for a bioretention soil
media that can be accessed at:
http://www.bae.ncsu.edu/topic/bioretention/design-soil.html.
- The bioretention soil should not be compacted with heavy equipment.
- The fertilizer specification should state that this is only an initial
application to establish the plants and after that fertilizer shall not be used.
- The use of Quercus Phellos (willow oak) is not recommended in a bioretention area
with an underdrain due to the high probability of the root system infiltrating the
underdrain.
- The correct scientific name of witch hazel is Hamamlis virginica.
- DWQ recommends a parallel underdrain in bioretention area no. 2 to provide back-up
in case of clogging.
That's all.
Annette
1 of 1 4/5/2007 10:57 AM