20071441 Ver 4_More Info Letter_20091113

FCI R
Notch Carolina Department of Environment and Natural Resources
Division of Water Quality
Beverly Eaves Perdue Coleen H. Sullins Dee Freeman
Governor Director Secretary
November 13, 2009
Mr. Jim Holman
Charter Properties, Inc.
1520 South Boulevard, Suite 215
Charlotte, NC 28203
Subject Property: Prosperity Village Development
DWQ Project # 07-1441v3
Mecklenburg County
REQUEST FOR MORE INFORMATION: STORMWATER MANAGEMENT PLAN
Dear Mr. Holman:
On April 29, 2009, the Division of Water Quality (DWQ) issued a 401 Water Quality Certification to
impact 0.231 acre of wetland and 386 linear feet of unnamed tributary to Stony Creek in order to
construct the subject development in Mecklenburg County. In order to meet Condition 8 of the 401
Certification for this project, a stormwater management plan (dated June 30, 2009) was received by
the DWQ on July 1, 2008. A revised stormwater management plan (dated November 11, 2009) was
received by the DWQ on November 12, 2009. The DWQ has determined that the stormwater
management plan was incomplete as discussed below.
Additional Information Requested:
1. Please address the following issues regarding the design of the bioretention cells:
a. The 3" hammered mulch layer should be omitted.
b. Filter media should be tested prior to installation instead of after installation (note on
Sheet 8.3)
c. Underdrain pipes should be lengthened so that they cover the entire area of the cell.
d. The Bioretention Rain Garden Plan Schematic on Sheet 8.4 does not appear to be
consistent with the designs you have proposed. The DWQ recommends that it be
omitted to avoid confusion.
2. Please address the following issues with the conceptual stormwater management plan:
a. Please provide a better explanation of the stormwater management plan phasing for
RG#1 and RG#2. The bioretention areas are sized to treat the impervious surface
from the roads only. The DWQ needs to know the intentions (in a conceptual
manner) for providing stormwater treatment when these drainage areas are
developed.
b. Please explain how the offline pretreatment proposed for future apartment sites UR-2
and R-22MF were sized.
4010versighUExpress Review Permitting Unit
1650 Mail Service Center, Raleigh, North Carolina 27699-1650
Location: 2321 Crabtree Blvd., Raleigh, North Carolina 27604
Phone: [phone] FAX: [phone]
Internet: http://h2o.enr.state.nc.us/ncwetlands/
NorthCarolina
Naturally
An Equal Opportunity 1 Affirmative Action Employer
Mr. Holman
Page 2 of 2
November 13, 2009
The DWQ will require the above additional information to finalize review of the stormwater
management plan for the subject property. Please provide the following information so that we may
continue to review your project. You are welcome to contact me at 919-715-3425 if you have
questions or would like to set up a meeting.
Sincerely,
Annette Lucas, PE
401 Oversight/Express Review Permitting Unit
AML/aml
Cc: Army Corps of Engineers, Asheville
DWQ, MRO
File Copy
Wendell Overby, S&EC, 248 LePhillip Ct., Concord, NC 28025
Filename: 071441 v3ProsperityVillage(Mecklenburg)_Sw_Hold2.doc