20211026 Ver 1_R-2511 4C Minutes_20210623

R-2511 4C Interagency Concurrence Point Meeting Minutes

Date: October 17, 2018
Location: NCDOT Structures Conference Room
Time: 1:00 PM
Minutes Authored By: Matthew Cook
Attendees: Kyle Barnes– USACE Garcy Ward – NCDWR
John Abel – NCDOT Div.1 Gretchen Byrum – NCDOT Div.1
Barry Hobbs – NCDOT Div.1 Paul Williams – NCDOT Div.1
Brooks Braswell – NCDOT Div. 1 Jason Dilday – NCDOT EAU
Cathy Brittingham – DCM Ken Hunu – Atkins
Lauren Sester – Atkins Debbie Barbour – KCA
Matthew Cook – RK&K Scott Blevins – RK&K
Brent Huskey – RK&K

Via Telephone:
Mark Staley – NCDOT Roadside Envir. Stephen Lane – DCM
Shane Staples - NCWRC

An interagency concurrence point meeting was held in order to reach agreement on concurrence point 4C for the R-2511 US-17 widening
project in Beaufort and Martin Counties. The following items were discussed and conclusions reached:

Matthew Cook began the meeting and introductions were made. Mr. Cook gave an overview of the project, stating that the project is eight
miles north US 264/Washington, five miles south of US 64/Williamston splitting Beaufort and Martin counties. Beaufort county is in the Tar-
Pamlico river basin that requires buffer filtration for all blue lines and Martin County is in the Roanoke river basin. The project is widening
10.6 miles of US 17 from two lanes to four lanes with open shoulder and grass medians. Anywhere on the project where an existing lateral
ditch is being filled in due to the widening a lateral ditch must be placed back. With requirements from Geotech there are additional ditches
proposed to allow the ground water to drain properly with the water table being at or close to the existing ground. The proposed outside edge
of travel must be five feet higher than the existing ground or five feet higher than the bottom of the ditch to meet the Geotech requirements.

Mr. Cook turned the meeting over to Brent Huskey. Mr. Huskey then began to go through the 4C permit drawings. He stated that for ease of
moving through the drawings, he would review buffer impacts as he reviewed wetland / stream impacts on the respective drawings.

Permit drawing 5 of 61, buffer drawing 3 of 9
Site 1, Stream SA, Wetland WA: Stream SA runs east to southwest through the project and is currently conveyed in a 60” CMP at -L-
18+27. The design team is proposing to retain the 60” CMP. This crossing is identified in USGS and soil survey mapping and is being
identified as jurisdictional in the JD. The proposed lateral swales entering the stream meet the design criteria for buffer filtration. There will
be stream and buffer impacts on the up and downstream sides of the site as well as wetland impacts upstream of the site due to the roadway
fill slopes moving laterally outward in the proposed condition. The four swales that are tying down to the stream for this site all meet the
buffer filtration requirements. Garcy Ward asked that the stream and wetland labels be placed on the buffer drawings. He also asked if the
ditches 50’ south of the project begin station were being modified. Mr. Huskey stated they were just tying in to them with the proposed R-
2511 ditches.

Permit drawing 8 of 61, buffer drawing 4 of 9
Site 2, Stream SB2, Wetland WB: Stream SB2 runs southeast to northwest through the project and is currently conveyed in a 48” RCP at -
L- 55+00. This crossing is identified in USGS and soil survey mapping and is only identified as jurisdictional on the downstream end of the
crossing in the JD. The proposed lateral swales entering the stream meet the design criteria for buffer filtration. The wetlands on the
upstream end will be impacted due to the road widening. There will be stream and buffer impacts on the downstream end of the crossing due
to the widening. The 48” RCP will be removed and a 60” RCP-III not buried with a 2GI-A will be installed in the final condition. The two
swales that are tying down to the stream for this site all meet the buffer filtration requirements. Mr. Ward asked that the Stormwater
Management Plan be checked. The required / provided buffer filtration lengths did not look correct. Kyle Barnes stated that the upstream

end of SB2 (right side of the road) was considered jurisdictional per field review May 14, 2018. Mr. Huskey stated that they will upsize the
pipe to a 66” RCP and bury it 1.0’. John Abel asked that the existing ground cross section shown on the pipe cross section on drawing 11 of
61 be checked to ensure that the pipe can be buried.

Permit drawing 13 of 61, buffer drawing 5 of 9
Site 3, Stream SB: Stream SB runs east to west through the project and is currently conveyed in a 48” RCP and a 6’x4’ RCBC at -L- 69+25.
This crossing is identified in USGS and soil survey mapping and is being identified as jurisdictional in the JD. The proposed lateral swales
entering the stream must meet the design criteria for buffer filtration. There will be stream and buffer impacts on the up and downstream
sides of the site due to the roadway widening. The 48” RCP and 6’x4’ RCBC will be removed and a proposed 8’x6’ RCBC buried 1.0’ and 2
@ 48” RCPs will be installed in the final condition. The additional 48” RCPs are required due to the headwater increase at the crossing
potentially affecting a structure upstream. The pipes provide a wider conveyance entrance to alleviate the waterway constriction occurring at
the RCBC. The four swales that are tying down to the stream for this site all meet the buffer filtration requirements. During 4B, Mr. Ward
stated that a portion of the bulb out for the roadway at -L- STA. 69+00 LT is inside the buffer zone for Stream SB. Since a bulb out is not
considered part of the roadway facility, it needed to be shifted out of the buffer zone area as part of the minimization efforts. Mr. Cook stated
that this revision had been made. Mr. Ward asked if riprap was used along the entrance and exit of the 2 @ 48” RCPs. Mr. Huskey stated
that riprap is used along the side slopes of the cut area but not in the overbank. Coir fiber matting is used on the overbank shelf. The
trenchless installation note will be removed from the pipe cross section, drawing 16 of 61.

Permit drawing 17 of 61, buffer drawing 6 of 9
Site 4, Stream SJ: Stream SJ runs east to west through the project and is currently conveyed in a 24” RCP at -L- 99+00. This crossing is
identified in USGS and soil survey mapping and is only identified as jurisdictional on the downstream end of the crossing in the JD. The
proposed lateral swales entering the stream must meet the design criteria for buffer filtration. There will be stream impacts on the
downstream end of the crossing due to the widening. The 24” RCP will be removed and 2 @ 42” RCPs-III not buried will be installed in the
final condition. Mr. Ward pointed out that the buffer impacts needed to be mitigable, not allowable, since they totaled more than one third of
an acre.

Permit drawing 21 of 61, buffer drawing 7 of 9
Site 5, Stream SC, Wetland WC): Stream SC runs east to west through the project and currently flows under an existing bridge at -L-
156+50. This crossing is identified in USGS and soil survey mapping and is being identified as jurisdictional in the JD. Wetlands extend well
beyond the buffer limits. For this reason, buffer filtration is not required at this site except at -Y4- 19+50 RT where it enters the buffer. The
existing bridge will be removed and dual 60’ single span bridges with 36” girders will be built for the final condition. This is the last site on the
project in the Tar-Pamlico river basin that has buffer filtration requirements. Mr. Cook asked if the temporary stream impacts should extend
from one side of the stream to the other even though temporary impacts are primarily expected on the left side. Mr. Barnes thought this was
acceptable. The permanent stream impact is due to a small portion under the fill slope that juts out from the main channel stem (-L- 156+25
RT). Cathy Brittingham asked why the roadway fill slopes were not 3:1 in the cross sections where wetlands were present. Mr. Huskey
stated that they could install 3:1 slopes.

Post Meeting Note: While 3:1 slopes can be installed in wetland areas, this might not be the least impact to the wetland. If the 3:1
slope is higher than 5’, guardrail needs to be installed which requires the roadway shoulder width to be widened 4’. This could
create even more impacts compared to slopes that are just over 3:1 (i.e. -L- 156+00 LT is 3.36:1). RK&K will investigate which
method creates the least impact to the wetland.

Permit drawing 25 of 61
Site 6, Wetland WD: The crossing runs west to east through the project and is currently conveyed in a 48” RCP at -L- STA 230+50. There
are wetland impacts on the downstream end of the crossing due to the widening. The 48” RCP will be removed and a 66” RCP-III not buried
will be installed in the final condition. Cross section -L- 229+50 LT will be verified for impacts using a 3:1 slope.

Permit drawing 29 of 61
Site 7, Stream SD, Wetland WE: Stream SD runs west to east through the project and is currently conveyed in a 30” RCP at -L- 280+40.
There will be stream impacts on the up and downstream end of the crossing as well as wetland impacts to the upstream side of the crossing
due to the road widening. The 30” RCP will be removed and replaced with a 48” RCP-III buried 0.8’ in the final condition. This will be called
out as site 7. Mr. Barnes requested that the Hand Clearing legend be added to the sheet.

Permit drawing 33 of 61
Site 8, Stream SE, Wetland WF): Stream SE runs west to east through the project and is currently conveyed in an 8’x3’ RCBC at -L-
346+50. There will be wetland impacts up and downstream of the crossing. The 8’x3’ RCBC will be removed and replaced with a 10’x5’
RCBC buried 1.0’ in the final condition.

Permit drawing 37 of 61
Site 9, Stream SF, Wetland WG: Stream SF runs west to east through the project and is currently conveyed in a double barrel 8’x6’ RCBC
at -L- 365+50. There will be stream and wetland impacts on the up and downstream end of the crossing due to the road widening. The
double barrel 8’x6’ RCBC will be removed and replaced with a double barrel 10’x8’ RCBC buried 1.0’ in the final condition. Cross section -L-
364+50 LT will be verified for impacts using a 3:1 slope.

Permit drawing 44 of 61
Site 10, Stream SK: Stream SK runs west to east through the project and is currently conveyed in a 4’x3’ RCBC at -L- 452+00. The
downstream end is the only side called out as jurisdictional so there will only be stream impacts on the downstream end due to road widening.
The 4’x3’ RCBC will be removed and replaced with a 48” RCP in the final condition.

Permit drawing 37 of 61
Site 11, Stream SG: Stream SG runs west to east through the project and is currently conveyed in a 36” RCP at -L- 499+00. There will be
stream impacts at the up and downstream end of crossing due to the road widening. The 36” RCP will be removed and replaced with a 66”
RCP buried 1.0’ in the final condition. Mr. Ward asked why there was riprap on the banks in two locations. Mr. Huskey stated that this was
for stability of the slopes, but that the channel bottom would not have riprap. Also, the riprap helps with the stream plugs required at these
locations to prevent the streams from migrating back to their original locations and undermining the roads.

Permit drawing 51 of 61
Site 12, Stream SH, Wetland WH, Pond PA: Stream SH is the first crossing on this plan sheet and runs west to east through the project
currently conveyed in a 30” RCP at -L- 512+00. There will be stream, wetland and pond impacts on the upstream end of the crossing and
stream impacts on the downstream end of the crossing due to the road widening. The 30” RCP will be removed and replaced with a 66”
RCP-III buried 1.0’ in the final condition. The pond that is on the upstream side of the crossing will be drained and the inlet of the pipe will be
moved to match with the natural channel. The construction limits note concerning wetland WH upstream of the pond will be modified to allow
temporary impacts due to construction.
Site 13, Stream SH2: Stream SH2 is the second crossing on this plan sheet and runs west to east through the project currently conveyed in
2 @ 24” RCPs at -L- 521+35. There will be stream impacts on the up and downstream end of the crossing due to the road widening. The
2@ 24” RCPs will be removed and replaced with a 54” RCP-III buried 1.0’ in the final condition. Mr. Barnes and Mr. Ward reiterated that
pipes in jurisdictional locations needed to be buried 1.0’, not 20% of the open area up to 1.0’. Therefore 48” and 54” pipes still needed to be
buried 1.0’. RK&K will verify that the conveyances provided will adequately convey the drainage given the correct burial amounts.

Permit drawing 56 and 58 of 61
Site 14, Wetland WI: At this site Wetland WI is delineated from -L- STA. 557+50 to 568+50 LT until it reaches the pond that is adjacent to
the roadway facility. There will be wetland impacts stretching from -L- STA. 557+50 to 568+00 LT where the new roadway fill slopes will be
encroaching into the wetlands due to the road widening. Toe projection will be placed only up on the fill slopes where the wetland impacts are
to protect the fill slopes from eroding. Cross sections will be verified for impacts using a 3:1 slope.

The meeting adjourned.

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