20191305 Ver 1_More Info Requested_20191211

Moore, Andrew W
From: Moore, Andrew W
Sent: Wednesday, December 11, 2019 12:52 PM
To: Melissa Ballard
Cc: Jeremy Cobb; mcampbell arcco.org; '[e-mail]'; Mcdaniel,
Chonticha
Subject: Request for Additional Information 3, Highlands Retail Development Project, Macon
County (DWR Project #20191305)
Melissa,
On September 27, 2019, the Division of Water Resources (Division) received your application dated September 26, 2019,
requesting a 401 Water Quality Certification from the Division for the subject project. On October 24 and 28, 2019, the
Division received your response to the Division's October 16, 2019, request for additional information. On November 26,
2019, December 2, 2019, and December 3, 2019, the Division received your response to the Division's November 5,
2019, request for additional information. The application is on hold until the following items are addressed:
The Division received the Highlands Site Design Plans rev11-22-19, which appears to show proposed elevations
associated with the stormwater management system approximately 2 feet higher than the plans received
September 27, 2019. In addition, it appears that additional detention chambers are proposed in the most recent
revision. Please provide a narrative description of the changes made in the design of the stormwater system
between the two revisions and a description of how the proposed elevations will be achieved. [15A NCAC 02H
.0506(b)(5)]
2. It appears that borings B-3 and B-8 were used to determine the approximate groundwater elevation and
approximate seasonal high water table (SHWT) in the location of the proposed stormwater control system. The
Geothechnical Engineering Report indicates that groundwater levels for the borings were identified for the short
duration the borings were allowed to remain open and that longer observations may be required to define
groundwater levels. Redoximorphic features were not evaluated in B-3 or B-8 to identify the SHWT at these
locations. The Geothechnical Engineering Report only identified the SHWT at B-9. Please explain how the data
reported in the Geothechnical Engineering Report are adequate to ensure the minimum 2-foot offset from the
SHWT will be met in the location of the proposed stormwater management system. [15A NCAC 02H .0506(b)(5)]
3. As there does not appear to be a boring in the footprint of the stormwater control detention system, and the
SHWT appears to have been inferred from a cross-section between two potentially unstabilized groundwater
elevations and/or a third boring location, will an on -site confirmation of the SHWT be conducted during
construction of the stormwater management system? [15A NCAC 02H .0506(b)(5)]
Pursuant to Title 15A NCAC 02H .0502(c), the applicant shall furnish all of the above requested information for the
proper consideration of the application. If all of the requested information is not received, the Division will be unable to
approve the application and it will be returned.
Feel free to contact me if you have any questions or would like to discuss further.
Andrew W. Moore, PG
Environmental Specialist — Asheville Regional Office
Water Quality Regional Operations Section
NCDEQ — Division of Water Resources
828 296 4684 office

email: [e-mail]
2090 U.S. Hwy. 70
Swannanoa, N.C. 28778
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North Carolina Public Records Law and may be disclosed to third parties.