20140957 Ver 2_NCDEMLR_RRO_ReqForAddInfo_09-15-17_20170915

Strickland, Bev
From: Castle, Sally Y
Sent: Friday, September 15, 2017 11:14 AM
To: Valentine, Thad; Baker, Chris
Cc: Davis, Tracy; Vinson, Toby; Cole, Brad; Coco, Julie; Neupane, Jeevan; LaBounty, Tim L;
Denton, Bill; Higgins, Karen
Subject: FW: Dominion Energy Transmission Inc. on behalf of Atlantic Coast Pipeline, LLC
From: Castle, Sally Y
Sent: Friday, September 15, 2017 11:10 AM
To:'[e-mail]' <[e-mail]>
Subject: Dominion Energy Transmission Inc. on behalf of Atlantic Coast Pipeline, LLC
Dominion Energy Transmission Inc. on behalf of Atlantic Coast Pipeline, LLC
NORTH -2018-004
The following comments pertain to the above referenced erosion and sedimentation control plan. Responses and
revisions received by September 22, 2017 will be included in this review.
Provide a copy of the USACE 404 permit and DWR 401 certifications for the office file. Provide a copy of
the DWR Buffer Authorization. Submit documentation with maps showing location and extent of impacts
to streams and wetlands with any special conditions pertaining to erosion and sediment control and
restoration of affected areas. Identify the streams, wetlands, and buffers on the plan sheets. Include any
additional measures on the plan sheets. (GS 113A -54.1(a)) Include the mileposts associated with the
stream and wetland crossings on the plan sheets. Provide an additional set of "List of Impacted
Waterbodies in NU sheets with the waterbodies unique ID listed in alphanumeric order.
2. Provide design calculations for peak discharge rate for the 10- year storm. Provide all supporting
data for the computation methods used (rainfall data for required storm events, time of
concentration/storm duration, and runoff coefficients used). (15A NCAC 04B. 0108)
Provide a detailed/specific construction sequence that coordinates the timing of land -disturbing
activities and the installation and removal of all proposed erosion and sedimentation control
measures. Provide a legend with symbols/icons to identify all sediment and erosion control
measures. Measures are to be to scale. Provide a construction sequence for all phases of
construction (including clearing and grubbing, pipe installation). Include the erosion control
measures that are applicable to each phase. A revised Financial Responsibility/Ownership Form
and additional fee may be necessary, if the total disturbed acreage exceeds the original
submittal. (GS113A-57(3), 15A NCAC 0413 .0105, 15A NCAC 04B.0106(5)) Specific Comments:
Provide a detailed construction sequence for each phase of the wetland crossings and each
phase of the stream crossings. This is to include the pipe installation in the stream crossing and
then a conversion phase from the pipe installation crossing to the through traffic stream
crossing (ie. Flue pipe to culvert with stone cover).
0 Address the inspection frequency for these sensitive areas.

• Is the entire pipe line going to be installed by open cut? No other method of pipe installation is
shown on plans. If other methods will be utilized indicate on plan sheets and include any
relevant details on the detail sheets.
• Specify which type of silt fence to use for the various field conditions (several plan details have
been provided).
• Describe the overall pipe installation process.
• Describe the stabilization of stream banks when the pipeline segment is complete.
• Describe various types of access/haul road construction.
• Describe the use of log mats, when to use trench plugs, dewatering of the trenches, turbidity
curtains, the stabilization of trenches and streambanks when the pipeline segment is complete.
• When will the silt fence adjacent to streams be installed? Before and after pipeline installation?
• The legend identifies "Stream Crossing" and "USFWS Stream Crossing with Enhanced
Controls". Provide a plan detail, construction specifications, and maintenance requirements for
each of these crossings. Do these structures supplement the crossings included in the plan
detail section?
• Temporary waterbars are to be installed prior to pipeline installation and permanent waterbars
are to be installed after pipeline installation. Please address this in the construction sequence.
• Are all stream crossings going to be performed via some method of damming and open cut
(Cape Fear)? No directional drill? If other methods will be utilized indicate on plans showing the
stations in which the other methods will be utilized and provide details of other methods on
detail sheets.
4. Provide design calculations for cross sections and method of stabilization for the planned
channels and the temporary diversion. Include appropriate permissible velocity and/or shear
stress data. Provide liners/matting where indicated. If liners/matting is to be installed, provide a
plan detail, construction specifications, and maintenance requirements. Identify the type of liner
and the location of the liner to be installed. Include the installation of liners in the construction
sequence. (GS 113A-57(3), 15A NCAC 04B.0113) Specific comment: This includes the ditches
associated with the access roads.
5. Provide inlet and outlet protection for all temporary pipes. Provide design calculations for
culverts and pipes. Provide design calculations, a plan detail, construction specifications, and
maintenance requirements for the outlet stabilization structures. Construction specifications for
the outlet stabilization structure are to include the width of the apron at the pipe outlet and at
the end of the apron, the length of the apron, the stone size, and depth of stone. (GS 113A-
57(3), 15A NCAC 04B .0113) Specific Comment: This includes access road culverts, culverts along
the pipeline, pipes and culverts used for stream crossings. Provide specifications for the
sandbags used as energy dissipators in the stream crossings, provide calculations or design
methodology to support the number of sandbags and placement of sandbags.
6. Include the NPDES 7/14 -day groundcover stabilization requirements table on the plan. Indicate
on the plan any areas that may require soil stabilization within 7 days. All areas requiring 7 -day
ground cover must be specifically identifed on the plan via leader line, hatching or some other
method. (GS 113A-57(2), 15A NCAC 04B.0106(3), NCG01 Section IIB (2)) 7 -day ground
stabilization is required for waterbars, temporary diversions, permanent ditches, etc.
7. Provide additional erosion and sedimentation control measures as required to protect all public
and private property from damage. Concentrated flow must be diffused using some type of
erosion control measures to prevent streambank erosion. (113A-57(3), 15A NCAC 04B

.0105) Specific Comment: Provide a silt fence outlet or other measures at low points along the
silt fence. Provide additional measures where grade exceeds 5% .
8. Identify the crossing methods for at all road crossings. Provide plan details, construction
specifications, and maintenance requirements for all crossing types. (GS 113A-57(3), 15A NCAC
0413 .0113)
9. Identify the locations where the pipeline will be bored. Provide adequate space for the bore
pits. Provide a plan detail, construction specifications, and maintenance requirements for the
bore pits. Provide adequate measures for the bore bits. (GS 113A-57(3), 15A NCAC 04B .0113)
10. Limit exposed areas and the time of exposure. (15A NCAC 04B .0106 (2) (3) Provide access to the
project at all road crossings. Provide construction entrances at all road crossings.
11. Provide detailed construction specifications and maintenance requirements for all proposed
sediment and erosion control structures (GS 113A-57(3), 15A NCAC 0413 .0113) Specific
Comment: Provide more detailed construction specifications for the stream crossings. Provide
maintenance requirements for the stream crossings. Provide maintenance requirements for the
access roads.
12. Provide a specific plan detail, specific construction specifications, and specific maintenance
requirements for the Coffer Dam to be used for crossing the Neuse River. Provide a specific
construction sequence to address this phase of construction. (GS 113A-57(3), 15A NCAC 04B
.0113)
13. Provide a plan detail and construction specifications for silt fence types that complies with the
skirt trench requirements per the Erosion and Sediment Control Planning and Design
Manual. (GS 113A-57(3), 15A NCAC 0413 .0113) Silt fence is to be trenched in 8 inches vertically
and 4 inches horizontally. The maximum spacing between posts is 8 feet (if there is a wire
backing) and 6 feet if there is no wire support.
14. Provide a method of dewatering the trenches (such as a silt bag). Provide a plan detail,
construction specifications, and maintenance requirements for this method. Include the method
of dewatering in the construction sequence. (GS 113A-57(3), 15A NCAC 0413 .0113)
15. Provide a plan detail, construction specifications, and maintenance requirements for the pipe
inlet protection. Provide a symbol in the legend and identify where these structures are to be
installed. (GS 113A-57(3), 15A NCAC 0413 .0113)
16. Provide a riparian seeding plan, a seeding plan for temporary vegetation (required for the entire
calendar year), and a. Provide the method of seedbed preparation and specify seed type and
rates, fertilizer type and rate, and mulch type and rates. (GS 113A-57(3), 15A NCAC 04B .0113)
17. Provide a note on the plans regarding the self -inspection requirement and include a link to the
combined self -inspection form on the DEMLR website
(http://deg.nc.gov/about/divisions/energy-mineral-land-resources/erosion-sediment-
control/forms). (GS113A-54.1 (e), 15A NCAC 0413.0131, NCG01 Section IIB (3))
18. Provide a note on the plans to contact the DEMLR Raleigh Regional Office at least 48 hours prior
to commencing the land -disturbing activity for each section of the project. Delineate and

number the work sections on the plans. The contact number is [phone]. (15A NCAC 04B
.106(b))
19. Provide two copies of the plan set (one full-size and one half-size), showing the modifications required for
approval. To facilitate DEMLR review, bubble, highlight, or otherwise identify the changes to your
resubmittal. (G.S.113A-57(4))
Sally Y. Ca4tle, F.I.
Regional Engineering Associate
Raleigh Regional Office
Division of Energy, Mineral and Land Resources — Land Quality Section
Department of Environmental Quality
919 791-4215 direct
919 791-4200 main
Email: sally.castle(cDncdenr.gov
DEMLR website: http://deq.nc.gov/about/divisions/energy-mineral-land-resources
Physical: 3800 Barrett Drive,
Raleigh NC 27609
Mailing: 1628 Mail Service Center
Raleigh NC, 27699-1628