20180133 Ver 1_TriangleTyreR5868_Memo_EllisDunn_080818_20180808

CAROLINA
ECOSYSTEMS INC. 3040 NC 42 West; Clayton, NC 27520
P:919-606-1065 — F:919-585-5570
MEMORANDUM
To: John Ellis — US Fish and Wildlife Service
Maria Dunn — NC Wildlife Resources Commission
From: Chad Coggins — NCDOT Division 4
Phil May - Carolina Ecosystems, Inc.
Cc: Samantha Dailey, USACE — Raleigh
Sue Homewood, NCDWR — Winston Salem
Eric Evans, Edgecombe County
David Revoir, P.E. — Appian Engineers
Subject: August 7 Meeting & Responses
Project Diamond - Triangle Tyre & R-5868
Kingsboro NC
August 8, 2018
On behalf of Edgecombe County and the NC Department of Transportation (NCDOT), we would
like to thank you both for your time in meeting and discussing the above referenced project
yesterday. Per our discussion, we are providing the following information to assist in completing
your review of the project:
- Sediment & erosion control inspection/maintenance summary
- Stormwater control summary
- Updated stream, wetland, and buffer impacts
- Future Kingsboro Select Site commitments from the County
Sediment and Erosion Control Inspection & Maintenance
The County and NCDOT are committed to ensuring that the Triangle Tire site and R-5868 are
constructed according to the approved grading and erosion control plans. As you are aware, due
to the implementation schedule NCDOT is administering and overseeing the grading and erosion
control for preparation of the site pad for Triangle Tyre, as well as the R-5868 access road and rail
line. Erosion control measures are installed on the site and work has begun, as previously
mentioned, in upland areas. The project will be required to comply with the NPDES Construction
Stormwater Permit NCGO10000, including areas with 7 -day ground cover requirements, self -
inspection and reporting requirements.
The contractor is responsible for maintaining and inspecting all erosion control devices. The
contractor is also required to have a Certified Level II Erosion Control/Stormwater Site
Management Inspector on site during all grading operations. Furthermore, all devices are installed
by a Certified Level 1 Erosion Control/Stormwater Site Management Installer.

Memorandum Project Diamond — Triangle Tyre & R-5868
John Ellis & Maria Dunn August 8, 2018
NCDOT has contracted with Gannett Fleming Inc, and there are three Certified Level II Erosion
Control/Stormwater Site Management Inspectors on site, one of which is a former NCDOT
employee with over 35 years in erosion control and construction experience. In addition to daily
site review and maintenance, official NPDES record keeping requirements are being followed for
this project which includes mandatory inspections once a week and after every 0.5 -inch rain
event. While we cannot guarantee 100 percent success of all measures in all rainfall events beyond
the design storm, constant maintenance and inspections will reduce the likelihood of failures and
result in immediate abatement and clean up. Erosion control measures with sediment build up will
be cleaned prior to major rain events to ensure capacity is maintained. Any discharges or failures
will be dealt with immediately.
Stormwater Control
As discussed in our meeting, the Triangle Tyre site stormwater design has been approved by a
professional engineer subcontracted for review and compliance with the Tar -Pamlico River basin
stormwater requirements. As such, the proposed stormwater control measures have been designed
and achieve the following criteria.
Per the Edgecombe County Stormwater Management Program for Nutrient Control, the site design
is required to meet the Tar -Pam nitrogen and phosphorus loading limits of 4.0 & 0.4 lbs/ac/yr. For
the immediate construction phase, Triangle Tyre plans to use the four (4) dry detention basins and
nutrient offset "in -lieu" fee payment to meet the Tar -Pam Nutrient Strategy requirements. After
installation of these stormwater control measures, the post BMP total nitrogen is estimated at 3.84
lb/ac/yr and total phosphorus is estimated to be 0.49 lb/ac/yr. Therefore there will be a relatively
small nutrient offset payment to buy down the phosphorus difference of 0.09 lb/ac/yr.
Triangle Tyre's site engineer is finalizing the site and grading plans, which will have less
impervious area than originally anticipated, and will decrease the anticipated nutrient loading and
offset fee.
There will be no net increase in peak flow leaving the developed site as compared to pre -
development conditions for the 1 -year 24-hour storm event. The post -development peak flow after
routing through the proposed ponds is actually 24% less than pre -development conditions based
on the preliminary design. The total impervious area is approximately 23.1% for the initial phase
of the project.
Proposed stormwater control measures will be owned and maintained by Triangle Tyre and subject
to Edgecombe County requirements for annual inspections in accordance with DEQ prescribed
Operation & Maintenance agreements. The new development must not cause erosion of surface
water conveyances. Each pond is designed to meet the following:
- Pretreatment (i.e. forebay) is required to settle sediment and prevent erosion.
- The location of the pond inlet and outlet are required to be located in a manner that avoids
short circuiting and increased flow paths.
- A low -flow channel is proposed through the basin to transport dry -weather flows and small
rainfall events.
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Memorandum Project Diamond — Triangle Tyre & R-5868
John Ellis & Maria Dunn August 8, 2018
The pond includes a small permanent pool near the outlet orifice to keep floating debris
away from the orifice.
Updated stream, wetland, and buffer impacts
Stream, surface water, wetland, and riparian buffer impacts are attached. The tables show the
initial application impact amounts, followed by the revisions. As documented in our June 2018
supplemental information, efforts to further avoid and minimize impacts associated with R-5868
have been ongoing and are reflected in the summary.
Future Kingsboro Select Site Commitments
We understand your concerns related to future development of other pads in the Kingsboro
Select Site. While there are frequent inquiries and interested parties, to date no other industry or
other development has committed to the Kingsboro Select Site. The County cannot make
absolute commitments regarding retention of forested buffers or implementation of stormwater
protection until specifics related to the individual site and industry are available. However, the
County will maximize retention of forested buffers for habitat and water quality protection on
each site pad, and over the Select Site as a whole, as much as practicable. In addition, the
County will work with future interested parties and promote consideration of bioretention and
other bio -engineered stormwater management devices internal to the sites if practicable. All new
development is required to comply with the requirements set forth by Tar -Pamlico Nutrient
Strategy Rules and the Edgecombe County Stormwater Management Program.
Again, we appreciate your time in meeting and reviewing the Triangle Tyre and R-5868 project
plans, and your understanding of the urgency to complete this review process and allow the
Section 404/401 permitting to be completed.
If you have any questions or need additional information, please contact Chad Coggins at
[e-mail] or [phone] or Phil May at [e-mail] or (919)
606-1065 at your earliest convenience.
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