20071556 Ver 2_More Info Received_20141015

CLearWater
ClearWater Environmental Consultants, Inc.
October 15, 2014 www.cwenv.com
Ms. Karen Higgins
NC DWR, 401 & Buffer Permitting Unit I
512 N. Salisbury Street, 9' Floor o 1
Raleigh, North Carolina 27604 OCT "' `C'�
RE: Big Ridge I Woo- r c ,/ r• ,,r 9on3
Request for Additional Infor�Mation
Jackson County, North Carolina
DWR # 07 -1556 I
Dear Ms. Higgins,
0C1 ( 72014
Please reference the comments received on September 22, 2014 (Attachment A) sent by
the NC Division of Water Resources (DWR) in response to the Nationwide Permit
Application for the site known as Big Ridge. The DWR has several comments regarding
the proposed project. Each comment is discussed below.
DWR Comment: "Please provide details regarding culvert removal and modifications,
including:
a. Step to work in the dry.
b. Stream channel reconstruction.
Current impacts at Impact C2 are approximately 80 linear feet. The culvert is
overly wide in this location and can be reduced in length to 40 linear feet. As
requested, the work would be done in the dry. Sand bags would be placed across
the stream in an appropriate location upstream of the existing culvert. Water
would back up behind the sand bags and be diverted around the crossing location
via a black corrugated pipe. The pipe outlet would be downstream of the crossing
location. Once the stream segment is dewatered, fill covering the culvert would
be removed and the culvert would be shortened. The day - lighted stream banks
would be sloped back, matted, and seeded with a native seed mix (Figure 1).
Culvert removals at C9, C10, and Cll would be treated the same way.
Contractors would remove the culvert at Cl l first, followed by C10, and then C9.
Approximately 60 linear feet of stream channel was relocated near the entrance of
the site. The stream would be put back into its original location. The
reconstructed stream channel would be constructed in the dry starting at an
existing riprap /soil berm to the existing culvert under Highway 107. The new
stream banks would be sloped back, matted, and seeded with a native seed mix
(Figure 1). Once the reconstruction is complete, the riprap berm would be
224 South Grove Street, Suite F
Hendersonville, NC 28792
828- 698 -9800 Tel
828- 698 -9003 Fax

Ms. Kam Higgins
10/15/2014
Page 2 of 3
removed to allow water to flow into the reconstructed channel and through the
existing culvert under Highway 107 to the Tuckasegee River.
c. Splash pool enhancement where pipes are perched, where appropriate.
Culvert outlet protection, in the form of splash rocks, would be placed below
perched culverts where appropriate if active erosion is occurring. Splash rocks
would be stone large enough to withstand high water flows. Splash rocks would
be placed even with the culvert outlet so that water would cascade over the rock
and into the stream.
d. Measures to prevent sediment loss to stream and turbidity impacts."
Road cuts within the project area are stable and no longer contributing significant
sediment to stream channels on site. Sediment and erosion control measures (i.e.
silt fencing) will be utilized at areas proposed for construction and any future
ground disturbance would be stabilized immediately with matting and seeding.
DWR Comment: "Water Quality Certification 3890 Condition 12 and Attachment A
require Stormwater Management planning, including the determination as to whether the
project is considered Low Density or High Density. No information has been provided to
meet this condition. Please provide the required details per Attachment A for such a
determination and the stormwater management BMPs to be utilized."
At this time, Amazing Grace, LLC has no intention of developing the property as a
subdivision. The current project purpose is to provide access to three lots on the
property and resolve the outstanding violation.
During an on -site meeting on September 12, 2014 with Chuck Cranford of DWR,
Mr. Cranford asked that the applicant estimate the impervious surface area at the site
if the residential development were to be complete. The Mount Wilderness project
area is comprised of approximately 360 acres. A site plan from 2007 proposes 74
lots ranging from approximately 1.5 -8.2 acres for an average lot size of 3.2 acres:
Potential house footprints are unknown; however, if a very liberal assumption is
made that an average of 10,000 square feet of impervious surface area would be
present on each lot, that yields a total impervious surface area of 17 acres for the
project site. Impervious surface area would likely be much less; however, total
impervious surface percentage based on the assumptions above would be 4.7 %. In
this instance, the development would be considered low density.
Although additional development is not proposed at the site, should the site be
developed in the future, stormwater runoff from built upon areas would be
transported by vegetated conveyances or alternative BMPs designed in accordance
with the NC DWQ Stormwater Best Management Practices Manual and approved
by the DWR. No collection systems would be utilized at the site.

Ms. Karin Higgins
10/15/2014
Page 3 U3
The information submitted in this package addresses all issues set forth in the DWR
comment letter dated September 22, 2014. Should you have any questions or comments
concerning this project please do not hesitate to contact me at 828- 698 -9800.
Sincerely,
i
Rebekah L. Newton R. Clement Riddle, P.W.S.
Project Biologist Principal