NHC Landfill Convenience Center -TRC Comment Responses 5.21.2021
ENGINEERING | DESIGN | TECHNOLOGY
5410 Trinity Road
Suite 102
Raleigh, NC 27607
P 919.866.4951
F 919.859.5663 www.timmons.com
May 19, 2021
New Hanover County Landfill Convenience Center – 5210 US Highway 421 North
Commercial Site Plan – TRC Review / Comment Responses
Planning, Ron Meredith 910-798-7441
Parking:
a) Please add to the site data table with the standards per Section 5.1.2.A of the UDO. Government
Offices and Buildings 2.5/1,000 sf.
RESPONSE: Site Data Table on the cover has been updated to show parking requirements
b) Please dimension the proposed parking spaces per Section 5.1.4.B
RESPONSE: Parking spaces have been dimensioned on Sheet L-210
Tree Retention:
a) Please be aware that there are new tree retention requirements with the UDO that have
updated the classifications of regulated trees. Please see Section 5.3.4 for more specifics. In
addition, trees preserved on the site may be credited toward mitigation.
RESPONSE: No trees being removed meet the definition of Regulated Trees, per Section 5.3 of the
UDO. The Existing Conditions and Demolition Plans has been updated with tree sizes and names.
Some trees previously shown on the plans do not exist as seen in current aerial imagery.
b) Please be aware that a Tree Removal Permit is required prior to any land disturbance activities.
Please provide the specific species (Loblolly Pine, Long Leaf Pine, etc.) of the trees to be
removed or retained to determine required mitigation.
RESPONSE: No trees being removed meet the definition of Regulated Trees, per Section 5.3 of the
UDO.
c) Please see the attached tree mitigation worksheet to help determine and verify required
mitigation.
RESPONSE: No trees being removed meet the definition of Regulated Trees, per Section 5.3 of the
UDO.
Fire Services, Raymond Griswold 910-508-0234
1. NHC Landfill - Redevelopment of the Convenience Center - 5210 N US Hwy. 421
2. I conducted a site visit of the complex on 4-7-21. Everything looks in compliance with the fire
code.
RESPONSE: Thank you
3. The only question or thought I have is that the Yard hydrant(s) have a threaded connection with
National Standard Threaded connection (2.5). Maybe a wye set-up could be used, one for the
water truck and one for the Fire Service.
RESPONSE: Yes, callouts were added on sheets U200 and U201 for the water truck only.
NHC Engineering (Stormwater) Galen Jamison 910-798-7142
1. A land disturbing permit from the State will be required for this project.
RESPONSE: The Environmental Management Department has been issued an erosion and
sedimentation control letter of approval and a Certificate of Coverage under North Carolina's
NPDES General Stormwater Permit for Construction Activities.
2. As the design is completed, submit all pipe and energy dissipater calculations as well as
associated drainage area maps for review to NHC Engineering.
RESPONSE: Yes, calculations are attached to this document.
3. Can the width of flat area adjacent the edge of pavement be reduced in order to avoid the 2.5:1
side slopes?
RESPONSE: For the purpose of providing safe access to the convenience center bay, we are
maintaining at least 5’ from the edge of pavement to the crest of the side slope. Detail D on
drawing D302 shows the slope stabilization measures that will be utilized for side slopes steeper
than 3:1.
4. The storm flow from ST-01 requires a change in flow path of more than 180 degree, can this be
avoided?
RESPONSE: Yes, an additional manhole was added which changed the geometry of the network.
See C100.
5. The contours from the facility exit (customer only) driveway stop at the edge of pavement and
the top 5’ of existing stockpiles are removed. Therefore, it’s difficult to determine if vehicular
movements are feasible at the new driveway.
RESPONSE: Yes, stockpiles have been removed on all drawings.
6. Is 1 retaining wall pipe drain outfall adequate?
RESPONSE: Timber wall pipe drain outlet callout for the convenience center bays was added to
C100.
7. What are the impacts of removing the pond’s forebay/percolation basin have on the NPDES
permit?
RESPONSE: The referenced sedimentation basin is temporary and is not part of the state
stormwater permit or the master stormwater plan as it will be replaced by a future landfill cell
expansion.
8. Is there adequate room in ST-15 sidewalls to handle a 24” and 15” pipe?
RESPONSE: ST-16 has been revised to provide adequate spacing. See C100
Cape Fear Public Utility Authority, Bernice Johnson 910-332-6620
1. Project plans show project to use existing well and septic tank.
RESPONSE: Yes
There is an existing non-potable well on site that will be abandoned. This well will be replaced
by a 4” irrigation well as seen on U200. For the water supply to the building, we are tapping into
an exiting 3” waterline that is supplied from a well near the administrative building, see sheet
C001 for location. A new septic system and drain field is to be installed per sheet U200 and
U201.
NCDOT, Patrick Wurzel, 910-398-9100
1. No comments
Environmental Health, Marie Hemmen 910-798-6664
1. Septic Improvement Permit has been secured and site inspected. Fill to be placed on site prior to
approval of septic construction authorization. Reference OSWPIP-21-0008
RESPONSE: Thank you
2. Will be tying to CFPUA water for new building. No drinking wells within 100 feet of septic
proposed system.
RESPONSE: No, our water supply for the water trucks and yard hydrants comes from a non-
potable 4” irrigation well, as seen on U200. The staff building will be supplied by an existing 3”
water line that supplies the administration building. The water well supplying the 4” water line
can be seen on sheet C001.
WMPO, Kayla Grubb 910-341-7890
1. NCDOT Projects: N/A
2. WMPO 2045 Projects: N/A
3. New Hanover County CTP: N/A
4. TIA: A TIA will not be required.
Planning (Addressing), John Townsend 910-798-7443
1. Contact planning for address assignment for new building(s)
RESPONSE: Planning has assigned the address 5280 US HWY 421 N, 28401 for this project site.
Thank you for your time to review our plans. Please do not hesitate to reach out to me with any
questions or comments as you go through our comment responses
Cheers,
Jon Blasco, PLA / ASLA
Landscape Architect
Timmons Group
Jon.blasco@timmons.com
919.532.3243