SW3240204_Response To Comments_20240402

azeri Hazen and Sawyer
9101 Southern Pine Blvd,Suite 250
Charlotte,NC 28273•704.357.3150
April 3, 2024
Brianna Holland
512 N. Salisbury Street, Office 625Y
Raleigh,NC 27604
Re: Grassy Branch WRF Expansion
Post Construction Stormwater Application—SW324024
Dear Ms. Holland,
Please find enclosed the requested revisions to this application. Included are two(2)hard copies of the
revised drawing set and one(1)hard copy of the revised narrative,which includes updated versions of the
required signed forms. This response letter addresses the comments received on March 5,2024.
Review Comment 1: Application Section III, 1 — Per the provided deed, the property owner is Union
County.Please revise the Applicant to Union County or complete the property owner information to Union
County with Union County Water applying on behalf of Union County.
• Applicant revised to be Union County.
Review Comment 2: This project drains to two receiving streams (it is acknowledged the streams
converge, but for stream accounting/tracking, we must document the BUA separately), please revise the
Application Section IV, 10 table and Supplement-EZ to reflect the drainage areas within the project area to
each stream.
• Requested revisions have been incorporated in the Application,Supplement-EZ,and Drawings.
Review Comment 3: Surface Water - A review of the latest USGS topographic map (clipped below)
indicates a stream on the property. 15A NCAC 02H.1042(2)(g)(iii)and Section VI, 8m of the Application
require incorporating this surface water area and its associated vegetated setback into the plans and omitting
this area from the project area. 15A NCAC 02B .0714(3)(a) allows relief from this requirement if a site
visit performed by authority staff that are certified pursuant to G.S. 143-214.25A confirms the absence of
surface water.
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• The intermittent stream has been incorporated on the Drawings and has been included in project
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area calculations per the recommendations of the stream assessment completed by NC DEQ on
March 11, 2024.
hazenandsawyer.com

Hazen Brianna Holland
April 3,2024
Review Comment 4: Supplement-EZ,Low Density Page, Swale Table:Please provide the BUA,Pervious
Area, and C value in the table.
• Updated and provided.
Review Comment 5:Please specify the type of permanent liner on the plans so the diversion ditch stability
can be verified through the provided engineering calculations. (15A NCAC 02H .1003 (2)(c)(iii).
• Swale label on Sheet C25 and Permanent Ditch detail (C-31-0450) on Sheet CD3 have been
updated to provide clarity.
Review Comment 6: As a vegetated conveyance is proposed within the project area, please revise the
O&M Agreement to include "vegetated swales/roadside ditches." This will generate additional
requirements in the manual for vegetated conveyance maintenance.
• Updated and provided.
Thank you very much for your consideration of the enclosed resubmittal. Please do not hesitate to reach
out to me with any questions by email([e-mail]) or telephone[phone]).
Respectfully submitted,
AA;c t 4 --1-2 R__L___,
Michael Parker, PE
Enclosure
cc: Thomas Mann (Union County Water)
Fred Braun (Union County Water)
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