20050732 Ver 19_Stormwater Approval_20110120

NCDENR
North Carolina Department of Environment and Natural Resources
Division of Water Quality
Beverly Eaves Perdue Coleen H. Sullins Dee Freeman
Governor Director Secretary
January 20, 2011
DWQ EXP # 05-0732v19
Chatham County
NNP - Briar Chapel, LLC
Attn: Mr. William Mumford
16 Windy Knoll Circle
Chapel Hill, NC 27516
Subject Property: Briar Chapel - Phase 4
APPROVAL OF STORMWATER MANAGEMENT PLAN (SMP) - MODIFICATION
Dear Mr. Mumford:
The Division of Water Quality (DWQ) has reviewed your application dated December 20, 2010 requesting for
modification to the previous SMP approval dated August 7, 2006 and subsequent DWQ approval modifications
dated October 31, 2007, November 3, 2008, June 30, 2009 and April 26, 2010. The requested modification
proposes a bioretention cell as a stormwater best management practice (BMP) device to treat the stormwater
generated on lots 349 - 353 as shown on the drainage area map and plan sheets (SW2, OAS-1, SD-l, B-1, B-2
and B-3) dated January 19, 2011 (Engineer's Sealed Date) and received on January 19, 2011.
The DWQ has reviewed and approves the proposed bioretention device to satisfy the stormwater condition
required by the Individual Water Quality Certification issued on May 9, 2006. You are required to meet the
following condition(s) in addition to those listed in the previous approvals:
1. The stormwater treatment system for this project area, consisting of a bioretention cell and the drainage
patterns depicted on the plans dated January 19, 2011, as approved by this Office must be maintained in
perpetuity. No changes to the structural stormwater practices shall be made without written authorization
from the Division of Water Quality. The stormwater management structures shall have maintenance access
and at least 10-foot drainage easement on each side to allow for the ability to maintain the structures, to
perform corrective actions and shall provide protection of the structures from potential alterations by future
property owners.
2. The maintenance activities listed in the notarized Operation and Maintenance Agreement, signed and dated
December 20, 2010 by Mr. William Mumford, must be performed to ensure effective operation of the BMP
device. The O &M Agreement shall be transferred with the sale of the property and DWQ must be notified
within 30 days of the transfer.
3. The applicant and/or authorized agent shall contact the DWQ Express Review Program in writing at the
letterhead address within ten (10) days of the commencement of construction.
This letter completes the review of the Division of Water Quality under Section 401 of the Clean Water Act. If
you have any questions, please contact Joseph Gyamfi at 919-807-6426 or Lia M. Gilleski at 919-807-6446.
401 Oversight/Express Review Permitting Unit
1650 Mail Service Center, Raleigh, North Carolina 27699-1650
Location: 512 N. Salisbury St, 911 Floor, Raleigh, North Carolina 27604
Phone: [phone] FAX: [phone]
Internet: http://portal.ncdenr.org/web/wq/swp/ws/401
NorthCarolina
Naturally
An Equal Opportunity 1 Affirmative Action Employer
05-0732v19 Briar Chapel - Phase 4 SMP Modification
Page 2 of 2
January 20, 2011
Sincerely,
,L ayL
Ian McMillan, Acting Supervisor
401 Oversight/Express Review Program
UM/j9
cc: DWQ Raleigh Regional Office
File Copy
Jeremy Finch, PE, EcoEngineering (John R. McAdams), P. O. Box 14005, RTP, NC 27709