19970694 Ver 1_Staff Technical Review Comments_20020307

O? W A T ?RQG Michael F. Easley
\ Governor
Ot
77
William G. Ross, Jr., Secretary
>_ y Department of Environment and Natural Resources
Gregory J. Thorpe, Ph.D., Acting Director
Division of Water Quality
T2'
March 7, 2002
Mr. John Schrum
The John R. McAdams Company, Inc.
PO Box 14005
RTP, NC 27709
Subject: Stormwater Sand Filter
The Gardens at Wakefield
Wake County, NC
DWQ# 970694
Dear Mr. Schrum:
The Wetlands Unit staff reviewed the stormwater management plans for the subject project and determined that additional
information is necessary to complete the technical review process. The required additional information is as follows:
1. Side Slopes and Settling Basin
The side slopes of the sand filter and the settling basin should be stabilized by grass or some other method. Please
specify this in the plans.
2. Sand
Please indicate the sand specifications on the plans.
3. Operation and Maintenance Agreement
An operation and maintenance agreement is required. Typical requirements for an operation and maintenance plan
include the following: -
• Vegetation management/mowing schedule
• Semi-annual inspections
• Check for 24 hour draw down and debris check after every storm event
• Schedule and procedure for sand removal and replacement
• Benchmark for sediment removal in settling basin
• Designation of a responsible party
The operation and maintenance agreement must also be signed by the responsible party and notarized. An
example agreement for an extended detention wet pond is available on line at
http://h2o.enr.state.nc.us/ncwetlands/oandm.doc.
Division wetlands unit staff will strive to complete a final technical review within 10 working days of receipt of the
requested information. If you have any questions or would like to discuss this project, please contact me at (919) 733-
9584. Also, please note that the NCDENR Stormwater Best Management Practices Manual, April 1999, and other
documents and information can be downloaded from the Wetlands Unit web site at
http://h2o.ehnr.state.nc.us/ncwetlands/. n
Sinc `?U' lI J
Tod t. John, P?
Environmental Engineer
cc: John Dorney, Wetlands/401 Unit
Raleigh Regional Office
File
North Carolina Division of Water Quality, 401 Wetlands Certification Unit,
1650 Mail Service Center, Raleigh, NC 27699-1650 (Mailing Address)
2321 Crabtree Blvd., Raleigh, NC 27604-2260 (Location)
919-733-1786 (phone), 919-733-6893 (fax), http://h2o.enr.state.nc.us/ncwetlands/