20150070 Ver 1_More Info Received_20150219

Johnson, Alan
From:Len Rindner <[e-mail]>
Sent:Thursday, February 19, 2015 9:44 AM
To:Johnson, Alan
Cc:Rob Reddick; Price, Robert
Subject:Fwd: FW: Willowcroft
Attachments:Post Development-Hydrology Inputs.pdf; 2014-12-11 Willowcroft Wetlands.pdf;
Willowcroft PRO-510625-030-CMP South.pdf; Willowcroft PRO-510625-040-CMP
NORTH.PDF
Alan:

This email is in response to our meeting on February 12, 2015. Attending the meeting was Rob Reddick with
John R McAdams. They are the planners and engineers for the project. Based on your comments the
stormwater management facilities will utilize an approved method from the NCDENR Stormwater BMP
Manual.

Based on a review of the plan and information provided by the engineer the stormfilter devices are proposed at
the major stormwater outfalls from the proposed development (upstream of the existing pond) to treat the
Stormwater Quality Treatment Volume. The proposed Stormfilter devices will treat the 1-inch rainfall and
provide the required 85% TSS removal in accordance with the Town of Stallings’ Post-Construction Storm
Water Ordinance (PCSWO) and the NCDENR BMP Manual. The dam on the existing pond will be upgraded to
meet current standards for this development. The existing pond dam is proposed to be maintained and modified
in accordance with Nationwide Permit #3 such that post-development peak flow rates are no greater than pre-
development levels in the 10-year and 25-year storm events. The information attached includes a summary of
our hydrologic analysis showing the amount of impervious per each drainage area/treatment facility.

Additional information regarding the design can be provided by Josh Allen, PE, CFM Project Manager - Water
Resources & Infrastructure and/or Rob Reddick P.E. with the John R McAdams Company.

We understand that based on your comments that the Approved 401 WQC will have Additional Conditions.
This condition will state that prior to any impacts to streams and wetlands that the stormwater management will
need to be approved by NCDENR - DWR in the central office and that the stormwater plan must implemented
prior to occupancy.

Thank you for your assistance and cooperation in resolving this complex situation. Let me know if you need
additional information.

Len Rindner

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Len Rindner
Leonard S. Rindner, PLLC
Wetlands and Environmental Planning Group
www.wetlands-epg.com
[phone]
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