20211426 Ver 1_Draft Mit Plan Comment Memo_NCDMS Falcon_SAW-2021-01274

DEPARTMENT OF THE ARMY
WILMINGTON DISTRICT, CORPS OF ENGINEERS
69 DARLINGTON AVENUE
WILMINGTON, NORTH CAROLINA 28403-1343

REPLY TO
ATTENTION OF:

November 22, 2023

CESAW-RG/Kichefski

MEMORANDUM FOR RECORD

SUBJECT: NCDMS Falcon Mitigation Site - NCIRT Comments during 30-day Mitigation
Plan Review, Macon County, NC

PURPOSE: The comments listed below were received from the NCIRT during the 30-
day comment period in accordance with Section 332.8(d)(7) of the 2008 Mitigation Rule.

USACE AID#: SAW-2021-01274 30-Day Comment Deadline: October 11, 2023
DWR #: 2021-1426v1

Andrea Leslie and Dave McHenry, NCDWR:
1) We appreciate the coordination that Wildlands staff have led to survey
hellbenders and incorporate design elements to preserve existing habitat.
2) The planting plan is great – the species list and intention to create 2 additional
cane breaks are both very appreciated.
3) As noted in an email and in the plans – although in-person monitoring did not
result in any hellbender records, eDNA results suggest that hellbender(s) are
indeed within the project. We Thus, when in construction, being especially careful
& watching for animals when working in the channel is important. That means
keeping an eye out and capturing any hellbender seen in a bucket to move it out
of harm’s way. The ‘out of harm’s way’ location is in the Cartoogechaye at
Cartoogechaye Baptist Church. Key times to watch for animals will be when
larger rocks that could be shelter rocks (typically 1-2 ft in diameter) are disturbed
and when flows are diverted around a section of channel (survey the drying
channel for animals several times). Please continue to coordinate with NCWRC
staff (Andrea Leslie and Lori Williams) on time-frame for the project.
4) While 3 wire electric is proposed, the possibility of woven wire is noted in the
draft plan. NCWRC requests that any woven wire fence that is used also be
gapped at the bottom about 6 inches to facilitate passage by some wildlife.
5) The placement of stone is recommended 1-2 feet immediately downstream of the
vertical drop structures in McCoy Branch. This may help create some interrupted
flow and complexity that can facilitate aquatic passage in streams that are often
fishless anyway. This may help also help resist pool scour if it occurs, possibly
due to the channel steepening in the riffles immediately upstream of the
structures. In addition to piping, pool deepening could be problematic if #57
stone is used instead of rock footers under the structures.
6) To help avoid piping, engineers should ensure that soil is compacted/sealed well
around structures and that the compaction also extend upstream to include the
subsoil under the geotextile and riffle stone. Backfill stone should be compacted
as well.
7) There are some, albeit few, mature trees that may be worth saving in restoration
and enhancement reaches. We recognize that this may be challenging to
accommodate with channel lowering proposed in this project. Any retention of
desirable trees is recommended and appreciated.
8) The streams may be transporting sediment reasonably well now. We hope that
sediment transport will continue to be effective with the shortened and steepened
reaches, and deepened pools, as proposed.

Maria Polizzi, NCDWR:
1) Photo points for crossings should show the crossing itself and both upstream and
downstream of the crossing. Typically this is done by having two photo points,
one on either side of a crossing. Consider adding an additional photo point at
each crossing, or describe methodology for fully capturing these locations with
one photo point.
2) How will wetlands be monitored to ensure that there are no unintended losses
associated with the project. Have wetland gauges been considered for the larger
wetlands? DWR requests that a wetland delineation be performed at least once
towards the end of monitoring to show the wetland extent at that time. This
information, including wetland data forms, should be provided in the subsequent
monitoring report.
3) DWR agrees with the DMS comment regarding the fencing plan. The location
and type of fencing should be included in the draft mitigation plan so that this can
be reviewed by the IRT prior to the permitting process. DWR understands that
minor changes to the plan may occur due to unforeseen circumstances, but a
proposed fencing plan should be included at this stage and any major deviations
at a subsequent stage will require further review.
4) Appendix 12/Fencing Plan: Will the 4-strand high tensile electric fence be
installed 2 feet outside the CE as requested in the DMS comment? If not, please
describe how fence maintenance will be performed to prevent both livestock
encroachment and/or easement encroachment due to landowner maintenance
activities.
5) Section 6.7.1: Text should be updated to reflect a planting window from October
15th-March 15th. Currently April 15th is listed as the end date.
6) DWR appreciates the inclusion of the reach summary tables with the reach
descriptions. This helps limit flipping back and forth and is much easier to
synthesize information about a specific reach. On future submittals, WEI could
also consider adding the proposed treatment (restoration, vs enhancement II,
etc.) and the proposed ratio to this table.
7) DWR recommends a ratio of 4:1 for James Creek Reach 4 and Allison Creek
Reach 2 since the stream has a SAM score of high, minimal planting is needed
and other in-stream work is limited to isolated bank grading.
8) DWR appreciates the inclusion of Table 15 and finds this to be helpful.
9) In section 3.5 a listed site constraint is high stream power due to large drainage
areas and moderate slopes. However, in Table 17 it appears that design
discharge will be considerably higher than existing conditions and reference
reaches. DWR wonders if decreased sinuosity to reduce meander bend erosion
is the best way to alleviate this problem, as this decrease in sinuosity
simultaneously increases stream power. Please provide some discussion around
this decision. If alternative design strategies were considered, please explain why
this option was selected. This discussion should include the fact that in-stream
devices can fail, either during monitoring or after, and how that may affect the
long-term stability of the reach/project.
10) Please make sure to include a figure with the final mitigation plan that shows
(with symbology on a map) the location of wetland impacts (both temporary and
permanent). This should include callouts for the name of the feature and size of
the impact that corresponds to the impact table.
11) DWR would prefer to see at least 50 ft buffers on all project streams.
12) Please add one permanent vegetation plot in the location of the mobile
vegetation plot at the downstream end of Jones Creek. It will be useful to have a
permanent plot fully contained within the wetland in that location.
13) DWR recommends adding a cross section in the location of existing XS4 or XS5.
14) DWR finds the pebble count particle distribution figures to be useful.
15) The detailed construction sequence is appreciated.
16) Due to the extensive cattle access on the project, how will topsoil stockpiling and
redistribution avoid excess nutrient and fecal coliform from being collected and
dispersed as a part of this process?
17) Based on the design plans it appears that most of the in-stream structures are
constructed riffles or bank stabilization. Very few cross vanes, sills or other
structures are proposed, and almost none that extend the full cross section,
except on McCoy Creek. Will constructed riffles provide the same level of grade
control as these cross-sectional features? I am not an engineer but want to make
sure I understand correctly. In general, why are constructed riffles the primary
grade control structure selected for this project?

Steve Kichefski, USACE:
1. The thorough comments from DMS are appreciated.
2. Livestock crossings 1 and 3, on James Creek Reach 6/7 are a concern for a
variety of reasons including sedimentation, stability and water quality. USACE
preference is not to have cattle cross under roads via the stream. While we
appreciate the improved ford crossings and inclusion of gates in these areas,
being external crossings, what control is there to ensure gates are not left open
and cows do not wallow in the stream? How stabile is the stream bed in both of
these crossing areas outside the CE where cows will have regular access? Were
over road crossings considered in these locations in order to prevent the
concerns expressed above.
3. Section 4.1: Make sure the Categorical Exclusion is updated prior to finalizing the
mitigation plan and submitting the PCN to reflect any changes that have occurred
since it’s signature on October 5, 2022. For example, ensure project
commitments for NLEB are still sufficient and if the TriColored Bat has been
listed consultation and project commitments should be addressed. Make sure to
note NCWRC trout moratoriums with the project planning and PCN submittal.
4. Table 20: Please confirm the proposed sinuosity of Allison Creek Reach 3 which
seems incorrectly listed in this table as 1.43.
5. While typically USACE would request different ratios for some of the project
reaches, especially the EII sections, due to the amount of functional uplift from
the work in these areas, however the additional no credit areas such as one
sided buffers and Waldroop restrictive covenant area are appreciated project
components.
6. It is clear that restoration areas will address stream dimension and pattern
through realignment and addressing lateral stability, however Section 6.6 and the
design plans do not provide as clear a picture of current channel
incision/floodplain access and what PI or PII profile work will be incorporated into
this project. Please provide more description in Section 6.6 and provide better
context regarding hydrological expectations for the many existing wetlands
throughout the project area, especially if the existing channel is moved further or
closer away. Depending on this discussion some groundwater wells may be
determined needed.
7. USACE supports DWR comments 9 & 12.
8. The PJD shows an intermittent creek entering James Creek from the pond to the
north along W Old Murphy Road. I could not find this feature on design plan
sheet 2.1.10. Is this feature entirely outside the CE due to the one sided
easement or will any portion of it include work?
9. Pg 15 section 3.5 Constraints discusses active flow management due to streams
too large for pump around. Make sure this is coordinated with agencies and
during NWP27 approval. Make sure they have plan in place for construction
during stormflows/predicted storm events and any time of year limitations to this
process depending on the species considerations. Under “General Notes and
Construction Sequence: General Stream, Wetland and Adjacent Construction”
item 6. Notes “In‐stream work should not be attempted on active streams during
high flow events.” This would be a place to provide further detail what
precautions will be taken to prevent failure of channel diversions infrastructure
when larger storm events are forecast.
10. If forested areas are disturbed beyond a minimal extent, seeding may not be
appropriate enough for re-establishing cover an and container plantings may be
needed.
11. Please explain further the need for the two internal easement exceptions
proposed along James Creek within the CE. These features appear to be
determined intermittent channels on the PJD. Will proposed work meet permit
conditions and encourage inappropriate stream impacts in the future. Can
alternative designs prevent routine maintenance and vegetation disturbance?

Sincerely,

Steve Kichefski
Project Manager
USACE Regulatory Division

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