20181031 Ver 1_Notice of Intent to Approve SAW-2018-01168_20201007

Strickland, Bev
From: Browning, Kimberly D CIV USARMY CESAW (USA)
<[e-mail]>
Sent: Wednesday, October 7, 2020 12:24 PM
To: Tugwell, Todd J CIV USARMY CESAW (US); Davis, Erin B; Wilson, Travis W.; Bowers,
Todd; Haywood, Casey M CIV (USA); Hamstead, Byron A; Leslie, Andrea J; Merritt,
Katie; Jones, M Scott (Scott) CIV USARMY CESAW (USA); McLendon, C S CIV USARMY
CESAW (USA); Smith, Ronnie D CIV USARMY CESAW (USA)
Cc: Reid, Matthew; Wiesner, Paul; [e-mail]; Tim Morris
Subject: [External] Notice of Intent to Approve/ NCDMS Round Hill Branch/ SAW-2018-01168/
Buncombe Co.
Attachments: Draft Mit Plan Comment Memo -Round Hill Branch_SAW-2018-01168.pdf
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Good afternoon,
We have completed our review of the Draft Mitigation Plan for the NCDMS Round Hill Branch Mitigation Site (SAW-
2018-01168). Please see the attached memo, which includes all NCIRT comments that were posted on the DMS
SharePoint site during the review process along with additional comments provided by Wilmington District staff
following our review of the IRT comments.
We have evaluated the comments generated during the review period, and determined that the concerns raised are
generally minor and can be addressed in the final mitigation plan. Accordingly, it is our intent to approve this Draft
Mitigation Plan (contingent upon the attached comments being addressed in the Final Mitigation Plan) unless a member
of the NCIRT initiates the Dispute Resolution Process, as described in the Final Mitigation Rule (33 CFR Section
332.8(e)). Please note that initiation of this process requires that a senior official of the agency objecting to the approval
of the mitigation plan (instrument amendment) notify the District Engineer by letter within 15 days of this email (by COB
on October 22, 2020). Please notify me if you intend to initiate the Dispute Resolution Process.
Provided that we do not receive any objections, we will provide an approval letter to NCDMS at the conclusion of the 15-
day Dispute Resolution window. This approval will also transmit all comments generated during the review process to
NCDMS, which must be addressed in the Final Mitigation Plan to be submitted with the Preconstruction Notification
Application for NWP 27. All NCIRT members will receive a copy of the approval letter and all comments for your records.
Thank you for your participation.
Kim
Kim Browning
Mitigation Project Manager, Regulatory Division I U.S. Army Corps of Engineers

DEPARTMENT OF THE ARMY
WILMINGTON DISTRICT, CORPS OF ENGINEERS
69 DARLINGTON AVENUE
WILMINGTON, NORTH CAROLINA 28403-1343
REPLY TO
ATTENTION OF:
CESAW-RG/Browning
MEMORANDUM FOR RECORD
October 7, 2020
SUBJECT: Round Hill Branch Restoration Site - NCIRT Comments during 30-day Mitigation Plan
Review
PURPOSE: The comments listed below were received during 30-day comment period in accordance
with Section 332.8(g) of the 2008 Mitigation Rule in response to the Notice of NCDMS Mitigation Plan
Review.
NCDMS Project Name: Round Hill Branch Restoration Site, Buncombe County, NC
USACE AID#: SAW-2018-01168
NCDMS #: 100066
30-Day Comment Deadline: September 4, 2020
USACE Comments, Kim Browninq:
1. For future consideration, it is helpful when all Figures are located in one appendix, rather than
scattered throughout the document. Additionally, the mitigation plan is typically located at the
front of the document, with the drawings and appendices located at the back. This may have just
been an issue with the hard copy.
2. Section 4, Credit Release Schedule: The IRT will review the Record Drawing/As-Built reports
according to the 2008 Mitigation Rule's streamlined review process prior to approving the initial
credit release. Please alter the statement regarding credits being released by DMS without prior
written approval of the DE.
3. It would have provided more functional uplift to the entire system to move the crossing on RHB
near the barn out of the existing wetland.
4. For future projects, it is recommended to set the conservation easement back at least 30-50 feet
from roads and road culverts to prevent future potential encroachments. It's difficult to discern if
that's what the Easement Exceptions are on Figure 10.
5. There is a lot of proposed channel to be filled. Please explain how a channel plug with a rock
core will function to plug the old channel?
6. Tables 14 & 15: 1 appreciate the inclusion of wetland status in these tables.
7. Section 6.9: Please include planting dates.
8. Page 31: Volunteers will only be counted towards success if they are on the approved planting
list. If you anticipate that the additional species listed in Table 15 will establish on -site, I suggest
adding some of these species to your planting list, as availability allows. This applies to the
Vegetation Performance standard as well. Volunteers will only be counted if listed in the
approved Table 14 planting list.

9. Page 34: Stream Hydrologic Performance for intermittent streams should be 30-days continuous
flow, at a minimum. Perennial streams are expected to have nearly continuous flow.
10. Figure 10: Please also include photo points at the culverts along Green Valley Rd. and Bridges
Cove Rd
11. Since approximately 15% of the project is Proposed as Priority 2, please include a veg plot in
one of the P2 bench cut areas to address soil fertility and compaction concerns associated with
veg establishment.
12.Section 4.1, Potential Site Constraints: It would be beneficial to discuss the potential for utility
line maintenance, and the future potential for road culverts to be replaced/widened, beaver
activity, invasives, etc.
13.Although wetland credits are not being sought, stream restoration will occur through existing
wetlands on site. It is not anticipated that overall wetland acreage will be lost, in fact it's likely
that wetlands may increase on site due to raising the channel. During monitoring year 5 please
re -verify the limits of jurisdiction to ensure that there was no net -loss of wetlands in -lieu of
installing monitoring gauges.
WRC Comments, Andrea Leslie:
1. Although the existing culvert is described as `not perched', Photo 4 on p.17 shows a culvert that
does not appear buried and is likely an issue for aquatic passage if not long term stability. We
recommend replacing this culvert.
2. We recommend finding a nearby reference reach for the vegetation community and using this
to tailor the planting list. Shafale's 2012 Natural Communities of NC does provide general
community descriptions but cannot be applied directly to every site. River Birch is found in large
river floodplains in the mountains and not small streams; this should be replaced with something
more typical of small streams, such as Sweet Birch. Likewise, Willow Oak is not a montane
species. We recommend enriching the planted species list with understory species found on
small streams in the area.
WRC Comments, Travis Wilson:
1. It's a little difficult to get a highly accurate assessment of the existing driveway culvert condition
and placement, but from the picture the culvert looks fairly aged. I can't tell if it's on bedrock or
was installed on top of boulder/rip-rap, but either way it is not buried. The driveway side
slopes look extremely steep and there is a lot of fill in the valley for there not to be any
additional high flow culverts. None of those conditions are preferred and ultimately could result
in a pipe failure particularly once woody debris is introduced into the system. We have
discussed the option of including crossings within the easement in order to assure future
maintenance or replacement is done properly, but I assume the easement has already been
recorded for this project. The only other option would be to replace the crossing with a new
and more adequate structure.
EPA Comments, Todd Bowers:
1. Table 8/Page 26:
• The measured D50 and D84 particle sizes for the proposed Reaches seems to be off by an
order of magnitude especially when considering the existing particle sizes of the same reaches. In
particular, RHB-3 and T2 are the reaches in question. This may be resulting in errors in calculated
critical shear stress for those reaches as well.
2. Table 10/Page 28:

• 1 am somewhat concerned that the floodprone width for RHB 2 is potentially wider (65 feet) than
the proposed riparian beltwidth of approximately 60 feet for this reach. This may result in hydrological
trespass and a risk to the nearby structures just outside of the conservation easement.
3. Table 15/Page 31:
• Consider using the volunteer list of species in determining alternative species to plant in lieu of
unavailable species or as a guide to understory development in the riparian Zone 2.
4. Section 8.0/Page 35:
• Recommend adding a couple more vegetation monitoring plots (one fixed and one mobile) to
adequately cover the site. The number of plots meets the 2% minimum coverage, however there are
two zones of vegetation planting and three main reaches so six plots may be more appropriate to
monitor the site effectively.
• Gauge on T1 needed to monitor intermittent flow of this reach. Recommend same approach and
update of Table 19.
5. Section 9.0/Page 39:
• Recommend listing the components of the site that may require adaptive management actions
(beaver, lack of flow, channel instability, lack of livestock exclusion, landowner encroachment, etc.)
6. General:
• Has there been any discussion or proposal to have the confluence of T1 and RHB moved further
upstream to allow for a full riparian buffer along the entire length of T1?
Note: It is understood that site visits may have been made by IRT members and other project managers
during the development of site feasibility to provide mitigation credit. In that regard, I feel it is necessary
to mention that I have not been on -site during this process and that my comments may reflect a lack of
on -site observation and evaluation.
DWR Comments. Erin Davis:
1. Page 8, Section 3.1.2 — Please provide a brief description of existing site vegetation, including
a list of invasive/nuisance species.
2. Page 20, Table 5 — Please confirm that the restoration entrenchment ratio should be a minimum
of 3.2.
3. Page 21, Section 4.1 — First, DWR appreciates that outreach was completed to relocate utilities
outside of the conservation easement. Second, what is the condition of the culverts on Bridges
Cove Road and Green Valley Road? Are any NCDOT projects planned for these roadways?
4. Page 22, Section 6.0 — With 25% of the watershed being agriculture/pasture, please confirm that
there are no offsite sediment loading concerns, particularly for T2.
5. Page 24, Section 6.4 — Please provide additional photo documentation to confirm that the
driveway culvert is not perched. When was this culvert installed?
6. Page 24, Section 6.6 — Please include the referenced rural mountain regional curve estimates.
Also, why weren't offsite reference reaches included for comparison? The IRT noted during the
site visit that restoration approaches needed to be justified in the mitigation plan and using only
onsite stable reference values infers that some stream sections do not warrant restoration.
7. Page 30, Section 6.9 — Please confirm the total area to be planted. This section states 3.68
acres to be planted, but Table 4 notes 4.24 acres.
8. Page 31, Table 15 — DWR does not support pre -approval of volunteer species to be counted
towards vegetative performance standard success. If veg plots are not meeting the required
stem density and diversity thresholds based on planted species, then volunteers can be
requested to count during the monitoring period review.
9. Page 34, Section 7.0 Stream Hydrologic Performance — Please specify that "intermittent" project
stream must show a minimum of 30 continuous flow days within "each" calendar year monitored.
10. Page 35. Section 8 Stream Hydrologic Monitoring — Since T1 is an intermittent stream, please
install a flow gauge in the upper one-third of the reach.

11. Page 36, Table 19 — Please add reference to a flow gauge on T1. Also, should there be an
asterisk footnote associated with the invasive mapping?
12. Page 39, Section 10 — DWR recommends annual inspections to confirm compliance with
easement conditions.
13. Figure 10 —
a. Please add a T1 flow gauge and shift the T2 gauge slightly downstream to within the
creditable reach.
b. Please reference the two random veg plots.
c. Please confirm that photo points for veg plots and cross sections not shown will be
included in the annual monitoring reports. Please also add a photo point downstream of
the driveway culvert crossing.
14. Sheet 4 — DWR questions the use of stone at the core of the channel block. Wouldn't this
facilitate water movement? Typically, a compact high clay content core is indicated for channel
block details.
15. Sheet 6 — There appear to be multiple "trees to remain" dots shown within the new stream
channel design. Please confirm.
16. Sheets 6 & 7 — DWR recommends that bench width be at least 1.5 times bankfull width.
Particularly of concern are some of the bench widths on the outer meander bends where much
of the flow energy vectors are directed based on the floodplain grading extent lines shown.
17. Sheet 8 — Please indicate easement break points.
18. Sheet 9 — DWR requests that no species (excluding live stakes) account for more than 20
percent of a specified planting zone in order to promote diversity within the designated
community type. DWR does appreciate the breakdown of the site into different planting zones.
19. Sheet 11 — DWR appreciates the inclusion of a fencing plan. Will there be any access points to
the easement area east of the driveway for site monitors and regulatory staff?
BROWNINGNM Digitally signed by
BROWN INGXIMBERLY.DA
BERLY.DANIELL NIELLE.1527683510
E.1527683510 Date: 2020.10.0712:16:53
04'00'
Kim Browning
Mitigation Project Manager
Regulatory Division