20201841 Ver 1_Draft Mit Plan Comment Memo SAW-2020-01962_20221005

From: Davis. Erin B
To: Baker. Caroline D
Subject: FW: [External] Notice of Intent to Approve/ NCDMS Bridgefork Dairy/ SAW-2020-01962/ Cleveland County
Date: Thursday, October 6, 2022 11:53:04 AM
Attachments: Draft Mit Plan Comment Memo NCDMS Bridoefork Dairy SAW-2020-01962.odf
Laserfiche Upload: Email & Attachment
DW R#: 20201841 v.1
Doc Date: 10/5/22
Doc Type: Mitigation Plan Review
Doc Name: Draft Mit Plan IRT Comments
From: Isenhour, Kimberly T CIV USARMY CESAW (USA) <[e-mail]>
Sent: Wednesday, October 5, 2022 3:41 PM
To: Tugwell, Todd J CIV USARMY CESAW (US)<[e-mail]>; Bowers, Todd
<[e-mail]>; Haywood, Casey M CIV USARMY CEMVP (USA)
<[e-mail]>; Davis, Erin B <[e-mail]>; Wilson, Travis W.
<[e-mail]>; Munzer, Olivia <[e-mail]>; Youngman, Holland J
<[e-mail]>
Cc: Reid, Matthew <[e-mail]>; Wiesner, Paul <[e-mail]>; Eric
Neuhaus <[e-mail]>; Crumbley, Tyler A CIV USARMY CESAW (USA)
<[e-mail]>; Fennel, Tommy E CIV USARMY CESAW (USA)
<[e-mail]>
Subject: [External] Notice of Intent to Approve/ NCDMS Bridgefork Dairy/ SAW-2020-01962/
Cleveland County
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Good afternoon IRT,
We have completed our review of the Draft Mitigation Plan for the NCDMS Bridgefork Dairy
Mitigation Site (SAW-2020-01962). Please see the attached memo, which includes all NCIRT
comments that were received during the review process along with additional comments provided
by Wilmington District staff following our review.
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; however,
please send the response to IRT comments prior to submitting the ePCN. 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 20, 2022). 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. Please contact me if you have questions or wish to discuss.
Be well,
Kim
Kim Isenhour
Mitigation Project Manager, Regulatory Division I U.S. Army Corps of Engineers 1 919.946.5107

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 5, 2022
SUBJECT: NCDMS Bridgefork Dairy Mitigation Site - NCIRT Comments during 30-day Mitigation
Plan Review, Cleveland County, NC
PURPOSE: The comments listed below were received during the 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.
USACE AID#: SAW-2020-01962
NCDMS #: 100171
NCDWR#: 20201841
30-Day Comment Deadline: August 20, 2022
DWR Comments, Erin Davis:
1. Page 5, Section 3.3.1 — Has any evidence of past/present beaver activity been observed
onsite?
2. Page 5, Bridgefork Creek Reach 1 a — Is the existing culvert under Patterson Road perched?
3. Page 19, Section 3.5 —
a. The new alignment of UT1 was designed to avoid working in the deepest pond
sediments, but is this location the appropriate natural valley low point?
b. Please describe what's ultimately done with pond bottom sediments in the MYO As -built
Baseline Report.
c. As part of the site constraints assessment and coordination, did NCDOT, Kings
Mountain Water or the electric utility company note any future maintenance plans?
DWR is concerned that stream credit appears to abut others' outfall structures along
UT2 and UT6. Was a credit setback considered in order to minimize the impact/risk of a
future encroachment request?
d. Also, there was no mention in Section 3.3.1-UT3 of the existing culvert being located
within the proposed project easement or in Section 6.6.7 that the culvert is proposed to
remain in place (Sheet 1.4.1). Why does the project easement include this structure
rather than start downstream of it? Dependent on the justification, DWR may request
that the easement be modified or require communication that DEQ Stewardship and
Kings Mountain Water have developed an acceptable plan for future structure
maintenance involving minimal buffer disturbance.
4. Page 20, Section 4.2 — Wetland credit areas appear to extend to the project conservation
easement boundary. Is there any risk of hydrologic trespass from these areas?

5. Page 23, Table 19 — The approaches and activities for UT4 Reach 1 and UT4 Reach 2 are in
the incorrect rows. Please update.
6. Page 29, Section 6.5 — DWR appreciates the reference to the Cleveland County
Comprehensive Land Use Plan.
7. Page 31, Section 6.6.1 - Please clarify supplemental planting "as needed". If supplemental
planting of understory/shrub species is being proposed to support an enhancement credit ratio,
DWR expects that all designated areas shown as Shaded Planting Zone on Figure 10 will be
supplementally planted with the listed Partially Forested Buffer Planting Zone species. And if
requesting a 2.5.1 ratio, DWR requires survival data be collected during monitoring. This
comment also applies to Bridgefork Creek Reach 2 and UT4 Reach 1. This was a discussion
point on enhancement reaches during the IRT site walk.
8. Page 31, Section 6.6.2 — Please show on a figure the extent of the P2 bench cut area(s)
greater than 12 inches within or adjacent to any wetlands, as well as any areas where P2
benches overlap proposed wetland credit areas. Is there a drainage effect concern with
proposing wetland credit within or adjacent to P2 bench cuts? Will removed hydric soil be
reused onsite?
9. Page 32, Section 6.6.5 — Please confirm whether the entire pond dam footprint will be removed
during construction after dewatering.
10. Page 32, Section 6.6.8 — The included design sheets do not callout any bank grading or debris
removal areas along UT4. Without knowing the extent of the functional uplift proposed, DWR
cannot support the requested 2.5.1 ratio. Based on the information provided, we believe a 4-1
ratio is more appropriate. Please submit any additional information for consideration prior to
finalizing the final mitigation plan. Also, please refer to the IRT site walk meeting minutes, "it
was noted that if bank work/grading were done as part of the work along UT4, the IRT would
require representative monitoring cross -sections be performed along the reach".
11. Page 34, Section 6.8 — General section note, DWR appreciates that pre -construction baseline
groundwater gauge data was collected, and we were glad to see a reference wetland
identified.
12. Page 34, Section 6.8.1 — Please confirm that reestablishment area Wetland 2A does not
overlap the pond dam footprint.
13. Page 34, Section 6.8.2 — Wetland K was evaluated to have a High NCWAM score. To account
for existing high wetland functions and lack of proposed monitoring stations to demonstrate
uplift, DWR believes an enhancement ratio of 2.5.1 is more appropriate for Wetland 2B.
Wetland approaches/ratios was a discussion point at the IRT site walk.
14. Page 34, Section 6.8.2 — Figure 2 shows three existing drainage ditches. Please add callouts
to fill ditches on design sheets.
15. Page 35, Section 6.8.3 — Regarding the preliminary/detailed soil investigation, is the single soil
profile provided representative of all nine proposed wetland credit areas? Why were no borings
taken within proposed wetland rehab areas? Also, has a sampling effort or any investigation of
the pond bottom sediments been performed?
16. Page 36, Section 6.8.3 — Is the proposed sediment cap expected to assist with access to
properly install bareroot plantings during construction and/or avoid sediment cracking during
monitoring? These are two challenges that DWR has observed in past proposed pond bottom
wetland credit areas.
17. Page 36, Section 6.9 — As part of Land Management, please provide a brief description of
proposed soil restoration to address equipment/haul road compaction, low nutrients/organics,
pH, etc. In addition to the pond bottom and P2 bench cut areas, there are several steep slopes

shown on the design sheets within and immediately adjacent to the project proposed for re-
grading and stabilization.
18. Page 37, Section 6.9 — In the MYO Baseline Report, please summarize what species were
treated prior to and during construction. The presence of Murdannia Keisak is particularly
concerning, so please provide a bit more information on the planned treatment of this species.
19. Page 37, Section 6.10 —
a. Given the site proximity to previously timbered areas, is pine or sweet gum colonization
a concern? Is veg management anticipated?
b. DWR recommends adding "no mow" signs along any internal utility crossings not
bordered by fence.
20. Page 38, Table 28 —
a. Dimension - Please add the entrenchment ratio for proposed B channels.
b. Hydrology - Please shift the semi -colon. Bankfull events are to be in separate years.
Minimum consecutive flow days is an annual performance standard.
c. Wetland — Please add start/end dates for the preliminary growing season.
d. Vegetation — Considering 70% of plantings for the Wetland Planting Zone are canopy
species, DWR does not agree with the proposed vigor standard modification without
further justification. DWR would support a vigor exemption for shrub and subcanopy
species across planting zones.
21. Page 40, Table 29 —
a. DWR requests a representative cross section be added to the approx. 200-ft restoration
reach of UT2.
b. In addition to permanent and mobile plots within the Figure 10 Open Planting Zone and
Wetland Planting Zone (which have an associated performance standard), DWR
requires stem survival data for supplemental planting within the Shaded Planting Zone
to support the 2.5.1 enhancement ratios. (Potential monitoring approaches were
recently discussed with Wildlands at the DMS Honey Mill IRT site visit)
22. General Comment — Please make sure to QAQC spelling, spacing, and formatting in the plan
narrative.
23. Figures 2 & 10 — Have red box comments already been incorporated into the figures? In the
future, DWR would appreciate figures at this scale and with this much detail to be
saved/printed as 11 x17.
24. Figure 10 —
a. Please change the UT3 preservation line color to match the legend.
b. There appear to be green and red groundwater gauges shown, which is confusing, and
they don't add up to the eight gauges noted in Table 29. Due to this discrepancy, DWR
may request changes to the number/locations of gauges once a revised figure is
submitted for review.
25. Sheet 0.3 —
a. Is the proposed log sill meant to be the angle log drop shown in the details? No log sill
detail was provided.
b. Since there are no callouts or details for channel/ditch plugs or partial backfilling, the
assumption is that all old channels and ditches will be backfilled to meet grade. Correct?
26. Sheet 1.2.3 — Please confirm with USACE, but I don't believe a vernal pool and stone outlet
BMP can be excavated out of an existing jurisdictional wetland area.
27. Sheet 2.7 — Please confirm whether the proposed floodplain pool is the same as the proposed
shallow vernal pool. If not, please provide a legend icon and typical detail for the floodplain
pool (including information on max. depth, outlet, materials/stone, planting/seeding).

28. Sheet 3.0.0 —
a. Please add CE lines to all wetland grading sheets.
b. This sheet shows Wetland Area 1 B not abutting the CE line in the northeast corner near
the utility break. This makes sense based on the topography shown on Sheet 1.1.1.
Figures 8 & 10 appear to show the wetland credit area extending to the easement line.
This is likely just a scale thing, but I wanted to confirm.
c. I appreciate the inclusion of wetland grading sheets. However, I find it very difficult to
assess proposed changes when the icon pattern covers the existing topography. What's
most helpful for me is a figure showing categorized proposed changes in wetland
elevations 0-6", 6-12" and >12" (often color -coded), so I can quickly assess minor to
moderate to more substantial changes in elevation and soil characteristics.
29. Sheet 4.0.0 —
a. Please double check species identified in the subcanopy stratum, particularly whether
swamp rose and elderberry should be considered shrubs.
b. Willow live stakes are included in the wetland planting zone percent stems total. Please
clarify if you're proposing to count live stakes as part of the density and vigor
performance standard monitoring.
c. Please consider adding milkweed species to seed mixes (as appropriate) for pollinator
habitat.
d. Regarding the sheet note, please see DWR comment on "as needed" buffer planting.
e. DWR greatly appreciates the attention given to species diversity and planting zones.
f. Please add CE lines to all planting plan sheets.
30. Sheet 7.8 (Educational Inquiry) — What is the purpose of the cattle slats?
31. Sheet 7.9 — Why isn't a single culvert feasible or a baseflow/floodplain pipe pairing? DWR
would prefer either of these options over a double culvert set at the same elevation in the
stream bed, which may over -widen the channel and scour the banks.
32. General Comment — With all the vernal pool outlets and BMPs, please try to embed the stone
lined areas as much as possible to limit layered stone voids that may become wildlife traps.
NCWRC Comments, Travis Wilson:
1. The ford crossings show the use of cattle slats; are these being used for structural stability to
help retain substrate in the ford? Or, are they intended to deter cattle from crossing the stream?
2. Crossing at the top of UT4 states the crossing will be determined in the final mit plan. The type
of crossing and configuration should be available in the draft mit plan. It's understood structure
sizes may not be known until a more detailed design and hydraulic analysis has been completed.
3. The culvert Detail on page 7.9 shows two lines of smaller diameter (24") pipe conveying the
normal flow channel. A single line of larger pipe, sized to carry the normal/low flow should be
used in this detail, if additional high flow pipes are necessary to convey flood flow they can be
incorporated within the cross-section at a higher elevation.
NCWRC Comments, Olivia Munzer.
1. We recommend planting only crimson clover rather than white clover for temporary and
permanent seeding (outside easement). White clover is a more aggressive, perennial species
compared to the annual crimson clover. White clover forms mats and can outcompete native
species.

2. Consider adding another 1-2 flowering herbaceous species to your wetland seed mix.
USACE Comments, Kim Browning:
1. Please include a grading map in the figures that shows the different depths that will be
graded. You can use different colors/patterns to show 0-6", 6-12', greater than 12".
2. Figure 10:
a. Please move the stream gauge on UT4A to the upper 1 /3 of the restoration reach,
closer to the photo point.
b. The legend doesn't clarify what the redish-pink dots in the wetlands represent. Are the
existing groundwater gauges? Will they remain? If not, please add additional gauges
to wetland 1 B and 2A, and shift the gauge near 4B so that it captures the wetland.
c. Is the preservation portion of UT3 supposed to be preservation for no credit? If so,
please adjust the map; this figure contradicts what's depicted on Figure 8.
d. Random plots will be requested in the supplemental planting areas throughout
monitoring, particularly along UT4 where invasives are removed.
e. UT2: Section 3.3 lists this reach as perennial and the DWQ ID Form lists it as
intermittent, and the pJD map shows the reach as perennial. Please clarify. If UT2 is
intermittent and has a 16-acre drainage area, please place a flow gauge near the
photo point.
3. Page 34 and Sheet 1.2.3: The shallow vernal pool/retention pond and stone outlet cannot
be placed in a jurisdictional area.
4. At the IRT site visit, the IRT questioned whether UT4 would remain stable after the extensive
removal of invasives with an Ell approach and requested cross sections on this reach.
5. Section 3.3: I appreciate the detailed existing conditions. This is helpful with the review.
6. Page 19: In addition to DWR's comments above on this section, please clarify that the
overhead utility crossings and the variable width waterline easement on UT1 are external to
the conservation easement. The design sheets indicate that the crossings are external, but
Table 16 and Figures 8 & 10 show these as internal easements. Our preference is to exclude
all existing utility easements, primary roads (i.e., NCDOT, city/county roads), maintained
residential driveways, greenways, or access corridors reserved for future development.
Additionally, why does the conservation easement boundary extend to Patterson Rd, to
include a 68' wide utility easement? This should be removed from the easement. Please give
me a call if you need to discuss.
7. Section 4.1: Was the pedestrian survey that was completed on March 9, 2020 conducted
during the appropriate survey window? Most are conducted during the growing season. Also,
keep in mind that plant surveys are only valid for 1-2 years, depending on the species. Due
to the presence of suitable habitat for Hexastyllis nanif/ora, but lack of onsite evidence for the
species' presence, the probability for project -mediated loss is insignificant and discountable.
I would concur with a "may affect, not likely to adversely affect" determination for this species,
not a "no effect.". I would encourage you to reach out to USFWS for written concurrence
because The Corps will need this to process the 404-permit.
8. Table 19: I think the descriptions for UT4 Reach 1 and 2 are mixed up. Reach 1 should be
Ell.
9. Section 6.5, page 29: What is the potential for future development to contribute additional
sediment? It appears that there are several developments close to the project currently.
10. Section 6.6.8: Please estimate the amount of bank grading that is proposed on UT4 in order
to justify the 2.5:1 ratio.
11. Section 6.8: On future projects, please keep wetland labels consistent with the pJD map. It's
confusing to have to refer to both Figures 2 and 8 in order to understand which wetlands this
section is referencing.

12. Section 6.10: What is the potential for hydrologic trespass onto adjacent fields? Stream
restoration work may have an impact on the hydrology of the adjacent land, resulting in
increased flooding and/or reestablishment of wetlands on those parcels. Given that the soils
and topography on the site do not immediately change at the edge of the conservation
easement, it seems logical that wetland reestablishment right next to the property line will
impact both sides of the boundary. There is also no way of ensuring that the adjacent
landowners will not construct new ditches immediately adjacent to your project that would
result in drainage of wetlands restored on your site. With no guarantee that the adjacent
parcel will not be transferred to a different landowner in the future, this potential site constraint
should be discussed in the text.
13. Table 28, page 38:
a. Please include the Entrenchment Ratio of no less than 1.4 for B channels.
b. If you would like to use a modified growing season that is not listed in the WETS
tables, you will need to measure the soil temperature using a continuous monitoring
device, and document vegetative indicators such as bud burst and leaf drop. Ideally,
this data would be collected prior to submitting the final mitigation plan so you have
accurate dates, similar to collecting pre -data for hydroperiods. If you decide to use a
modified growing season, once you establish the dates (assuming it's a normal year),
you will need to stick with those dates throughout the life of the project for consistency.
Kim Isenhour
Mitigation Project Manager
Regulatory Division