SW6130203_Response To Comments_20240423

HILLIARD
PO Box 249,Sanford, NC 27331
[phone]
To: TRANSMITTAL
Division of Energy, Mineral&Land Resources
Stormwater Program
Att:Jim Farkas
1612 Mail Service Center
512 N.Salisbury Street
Raleigh, NC 27699-1612
Date: 04/24/24
Project: O'Reilly Auto Parts Area Infiltration Basin
HE#: HC2301
Please find enclosed the following:
One(1) Original Hard copy of high-density commercial deed restriction form
One(1) Original Revised application
One(1) Original Revised supplement form
One(1) Original Infiltration Basin Stage Storage Calcs for The Treatment Area only
Two(2) Copies Plan Set
Per comment letter received April 10th,2024, and discussed via telephone conference call on April 22,2024 at 9:30 am, please
find below our response to comments provided:
1. Renewal application being approved is noted.
2.The high-density commercial deed restriction form has been completed and is included in this submission.
3. BUA's have been revised in the application and the supplement form to match
4.The design volume has been defined as the volume from outlet pipe elevation to bottom of portion being called the treatment
portion of the overall basin. This volume and bottom surface area has been designated on the plans and calcs updated to
reflect this portion. The outlet couldn't be lowered as it is at the lowest point on the property. As such,a portion of
the basin has been designated just for treatment and the remainder to try to manage storms larger than a 1"storm to prevent that
portion from being defined as the'design volume.'
5.The forebay was originally included in the stormwater easement, but with so many lines in the CAD drawing,one of the lines
were on top of a property line and the easement line went through this. In an effor to make it stand out more on paper,the
easement line has been made thicker.
6.The table in IV. 10 has been updaed per comment 3.
7.The supplement EZ form has been updated per comment 3. Line 18 show the percent imperivous for Entire site and DA 1.
Line 20 in the DA 1 Column was a typo and should match the same design volumes shown in Infiltration Sheet Line 2 and Line 44.
The SHWT figures have been updated to show a"<"sign as requested in the comment letter.
Line 44 matches line 2 and line 20 from the DA sheet. Line 46 has been deleted all together per our conversation on 4/22/24 since
it is shown on the plans that a forebay is being used.
Please let me know if you have any questions or need any additional information.
Jarrod E. Hilliard, PE,CFM
Hilliard Engineering, PLLC