HomeMy Public PortalAbout333080M
Metropolitan
St. Louis Sewer
District
2350 Market Street
St. Louis, MO 63103-2555
(314) 768-6200
October 6, 2008
Mr. Skip Short
Eastern Regional Manager
Kristar Enterprises, Inc.
4020 Riverclub Drive
Cumming, GA 60041
RE: KriStar FlogardDual-Vortex HDS: St. Louis MSD Submission
Highway Use Level (HUL) and Redevelopment Use Level (RUL)
Approval within District
Dear Sir:
The Metropolitan St. Louis Sewer District (MSD) has reviewed your application regarding the
Flogard® Dual -Vortex HDS for use as a Best Management Practice for stolniwater management.
MSD is pleased to provide Redevelopment Use Level (RUL) and Highway Use Level (HUL)
approval for use of the Fiogard® Dual -Vortex HDS as a stand-alone water quality BMP, subject
to the following provisions.
• The Flogard® Dual -Vortex HDS is only approved for use at public highway and roadway
projects and for redevelopment sites less than 5 acres. This approval is based upon
compliance with requirements listed in MSD's Proprietary Water Quality Products and
the MSD's Stormwater Management Program (January 2008).
• The Flogard® Dual -Vortex HDS must be sized to capture all floatable trash and free oil,
and remove 80% of total suspended solids for the OK-110 particle size distribution at the
site water quality flow -rate (WQf). Procedures for calculating WQf are provided in
Appendix D.10 of the Maryland Stoiniwater Design Manual (2000). Table 1 provides a
list of approved models and their respective peak treatment WQf.
Table 1: Flogard Dual -Vortex HD
System Model
Max Treatment Flow (cfs)
DVS-48
0.5
DVS-60
0.9
DVS-72
1.4
DVS-96
2.8
• Devices should be configured as off-line units.
• All devices shall provide a minimum sediment storage capacity of 10 ft3.
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