20181274 Ver 1_eApproval Letter SAW-2018-01784_20200714

Strickland, Bev
From:
Browning, Kimberly D CIV USARMY CESAW (USA)
<[e-mail]>
Sent:
Tuesday, July 14, 2020 1:40 PM
To:
Baumgartner, Tim
Cc:
Jeff Keaton; Phillips, Kelly D; Wiesner, Paul; Tugwell, Todd J CIV USARMY CESAW (US);
Davis, Erin B; Haywood, Casey M CIV USARMY CESAW (USA); Wilson, Travis W.;
Bowers, Todd; Leslie, Andrea J; Byron Hamstead; Merritt, Katie; Crumbley, Tyler A CIV
USARMY CESAW (USA); Jones, M Scott (Scott) CIV USARMY CESAW (USA); McLendon,
C S CIV USARMY CESAW (USA)
Subject:
[External] eApproval Letter/ NCDMS Lyon Hills Site/ Wilkes County/ SAW-2018-01784
Attachments:
Draft Mit Plan Comment Memo -Lyon Hills_SAW-2018-01784.pdf; eApproval
Letter -Lyon Hills_SAW-2018-01784.pdf
Follow Up Flag: Follow up
Flag Status: Completed
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Mr. Baumgartner,
Attached is the Lyon Hills Draft Mitigation Plan approval letter and copies of all comments generated during the project
review. Please note that this letter approves the Draft Mitigation Plan provided that the Final Mitigation Plan
adequately addresses all comments on the attached memo. Please provide a copy of the Final Mitigation Plan when you
submit the Preconstruction Notice for the NWP 27. If no permit is required to construct the project, please submit a
copy of the Final Mitigation Plan to our office at least 30 days prior to beginning construction. Also, please ensure that a
copy of the Final Mitigation Plan is posted to the NCDMS project documents so that all members of the IRT have access
to the Final plan.
Please let me know if you have any questions about the process or the attached letter.
Respectfully,
Kim
Kim Browning
Mitigation Project Manager, Regulatory Division I U.S. Army Corps of Engineers
3331 Heritage Trade Dr, Ste. 105 1 Wake Forest, NC 27587 1 919.554.4884 x60
BUILDING STRONG

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
June 25, 2020
SUBJECT: Lyon Hills Mitigation 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: Lyon Hills Mitigation Site, Wilkes County, NC
USACE AID#: SAW-2018-01784
NCDMS #: 100085
30-Day Comment Deadline: May 24, 2020
USACE Comments, Kim Browning:
1. Please include photos of culverts/crossings in monitoring reports.
2. Please show location of existing wetlands on Figure 8.
a. Please add a veg plot to the wetland area along UT1.
b. It is preferred to move the crossing on UT1 out of the wetland, closer to the confluence.
3. UT1: The neighbor's existing spring box drainage pipe, and its discharge into the channel, is not
permitted within the conservation easement. Please remove.
4. During planting, if species substitutions occur due to availability or refinement, please red -line
the As -Built and MYO report if substitutions occur.
5. Table 5 lists five existing invasive species. Please include a performance standard addressing
the control of invasive species to less than 5% of the conservation easement.
6. Section 3.4: Please update with PJD received June 11, 2020. Also, please add discussion
regarding work that will be done on (UT1) the adjacent landowner's property in connection with
this project.
7. UT4: There is concern that raising the channel bed at the upper end will cause loss of flow.
Please add a gauge in the upper 1/3 of the reach.
8. Recommend removing silver maple from the planting list, as it can be invasive.
9. Section 6.7: Please add the target community type and planting window.
10.On future planting plans, please add a column that designates whether the species is FAC,
FACW, etc.
11. Section 3.8: 1 appreciate the thoughtfulness of this section. It may be beneficial to add discussion
on crossing and culvert maintenance, especially the ford.
12. Table 20: Since several of the reaches are designed as B type channels, please include a
performance standard of ER no less than 1.4 for B channels.

13. Please provide a brief description on where the spoil from the bond bottom will be spread, and
the method of fescue removal.
14. Section 6.6: An overall discussion regarding the different types of BMPs proposed, materials
used, approximate depth, vegetation (if any), and necessary maintenance would be helpful since
these features are within the easement boundary.
USACE Comments, Casey Haywood:
1. Table 1 Project Information, Project Coordinates- please annotate degrees with symbol
2. Table 2 Add the "0" at the beginning of the 8-digit HUC so that it reflects 8-digits
3. Section 3.1 paragraph 2, 3rd to last sentence "The other tributaries have small watersheds the
are contained within the project site and adjacent parcels." Please change "the" to "that".
4. Table 3: Drainage Areas and Associated Land Use- Land use source- National Land Cover
Database 2011 (NLCD 2011), Multi -Resolution Land Characteristics (MRLC) consortium; why
not use the most up to date 2016 NLCD database? Is it much different than 2011?
5. Section 3.4 mentions evidence of prolonged saturation within the upper 12 inches of the soil
profile; were groundwater gauges installed? Please provide this data if it is available and
reference it within the document.
6. Section 3.6, 1st paragraph, Table 6 is highlighted
7. Section 3.7 paragraph 2 typo "These project components are described in Section 4 in terms of
goals, objectives, and outcomes for the project and in in greater detail as the Section 6 in the
project site mitigation plan."
8. Section 3.7 last paragraph, "There is little concern that if the site is properly constructed and
maintained that the project goals will not be met." Will or will not be met? Is this a typo?
9. Section 5.2 last paragraph, typo "Wildlands has acquired a temporary construction agreement
with this landowner who is please that the project will involve fixing the headcut."
10. Section 6.6 "The upstream end of the reach will tie into an existing culvert and the bed will
be raised somewhat but kept low enough in the valley to allow for neighbor's existing spring
box drainage pipe, which currently discharges to the channel, to remain in place
approximately 65 downstream of the culvert." Please add distance, is it 65 feet?
11. Table 19 Determination of Credits indicates a bridge crossing on Hanks Branch, reach
2; however, this is not noted in Table 6: Easement Breaks and Crossings. Additionally, Table
19 does not note the internal culvert crossing on Hanks Branch reach 3 as noted in table 6.
Are there actually 7 crossings on this site or six? Is there a reason they are not shown on both
tables?On figure 8 Concept Map it shows the crossing on Hanks Branch reach 3 but not on
reach 2.
12. Section 12.0 References; please reference the use of the National Land Cover Database
2011 (NLCD 2011) and any other documents mentioned in the document.
DWR Comments, Erin Davis:
1. DWR appreciates the high connectivity of the site, as well as the inclusion of stream origins and
addition of BMPs. Also, the mitigation plan format made for an efficient review, including the
concise text, descriptive tables and photos. The discussions on risks and uncertainties and soil
treatment of bench cuts were good to see.
2. Page 1, Table 1 - On the DMS comments page 2, a response states the easement area as
20.29 acres. Table 1 specifies 20.72 acres. Please confirm.
3. Page 9, UT3 - Please include a sentence on the existing condition of UT3 Reach 4.
4. Page 11 & Page 25, UT 4 - The IRT meeting minutes mention a dewatered pond bed within
UT4 Reach 1. Is this the area mapped as Wetland Y? Is working within the relic pond bed
sediment a concern?

5. Page 17, Section 5.1 - More than 0.35 acres of wetland is proposed to be permanently impacted
by the project, primarily along UT1. The proposed UT1 crossing spans a wide area of existing
wetland. Please include an explanation for why this crossing couldn't be located further upstream
to reduce wetland impacts.
6. Page 18, Table 10 - Please add "replanting buffer" to Sparks Creek and Hanks Branch R1. Also,
please add a row for UT3 Reach 4.
7. Page 24, UT1 - Can you briefly describe the condition of the existing culvert that UT1 will tie into
(e.g. adequately sized, perched, partially buried).
8. Page 25, UT4 Reach 1 - Echoing DMS question, with the UT4 DWR Stream ID Form score
close to the perennial/intermittent threshold, is there a concern that raising the bed will alter the
flow regime from perennial to intermittent? DWR may request a flow gauge following the post -
construction review.
9. Page 25, UT5 - Has the existing pond sediment been assessed? How will the sediment be
handled/reused onsite?
10. Page 26, Hanks Branch - The IRT meeting minutes' note creating floodplain benches on both
sides of Reach 3. Please explain why only a right side floodplain bench is now proposed and
how this effects the potential functional uplift.
11. Page 27, Table 19 - The IRT meeting minutes note "improving the buffer by planting native
trees" along UT2. However, the existing conditions section describes a mature canopy and Table
10 does not mention replanting. DWR supports a 3:1 ratio for UT2 based on existing conditions
and potential functional uplift.
12. Page 29, Section 10 - Please define the max. duration between "periodic" inspections.
13. Figure 6 - Please indicate any existing culvert crossings.
14. Sheet 1.04 - As DMS noted, please address the callout "avoid existing water line". Please
assess the condition of the pipe and remove from the easement if possible.
15. Sheet 1.08 - Table 10 notes wood being added to Hanks Branch R2, please callout these areas
on the design sheet. Also, do the "remove tree" callouts indicate hazard trees not located within
the proposed grading areas?
16. Sheet 1.09 - Can you please explain why the proposed rock outlet is necessary.
17. Sheet 1.14 - It would help our review to see the existing channel area proposed to be filled as
a shaded feature on the plan view sheets.
18. Sheets 1.21-1.23 - Please assess the banks along UT3 Reach 2 and Reach 3 that have callouts
to "repair trampled stream banks per Engineer's direction" and include specific proposed
actions/features in the final design plan.
19. Sheet 2.00 - Either on the design sheet or in the mitigation plan text, please indicate that the
proposed BMPs are designed to not require long-term maintenance.
20. Sheet 2.01 - Please confirm that the proposed rock sill is being installed over existing bedrock.
21. Sheets 2.02 & 2.03 - These BMPs are described as ponds in Section 6.6. Are they designed to
wet year-round? They are not included in the planting plan, but please confirm at minimum the
side slopes will be vegetated. DWR would like to see planting within the BMP ponds if possible.
22. Sheet 3.0 - Please consider a wetland planting zone replacement species for American Holly,
which is FACU. Also, have you had success planting Helesia tetraptera in restoration wetland
areas? I was not able to identify its wetland indicator status.
23. Design Plans - Please include an overall fencing plan indicating existing and proposed fencing
and approximate locations of anticipated gates.
WRC Comments, Travis Wilson:
1. 1 like the site -specific culvert crossing details shown in the back of the plans. They were also
depicted in the plan view, however they were not identified in the plan profiles. For review

purposes it is beneficial to record the culvert invert elevations on the profiles as well as the road
crossing elevation.
2. "Outlet stabilization" is shown for each outlet in the plan view detail. A note should be included
in this detail to embed the stone into the stream bed substrate. Any outlet protection should
function more as an armored plunge pool or bedrock and not a rip rap dissipater pad.
BROWNING.KIMB Digitally signed by
BROWN INGXIMBERLY.DANIEL
ERLY.DANIELLE.1 LE.1527683510
Date: 2020.06.25 15:05:43
527683510-04'00'
Kim Browning
Mitigation Project Manager
Regulatory Division

REPLY TO
ATTENTION OF:
Regulatory Division
DEPARTMENT OF THE ARMY
WILMINGTON DISTRICT, CORPS OF ENGINEERS
69 DARLINGTON AVENUE
WILMINGTON. NORTH CAROLINA 28403-1343
July 14, 2020
Re: NCIRT Review and USACE Approval of the NCDMS Lyon Hills Mitigation Site / Wilkes
Co./ SAW-2018-01784/ NCDMS Project # 100085
Mr. Tim Baumgartner
North Carolina Division of Mitigation Services
1652 Mail Service Center
Raleigh, NC 27699-1652
Dear Mr. Baumgartner:
The purpose of this letter is to provide the North Carolina Division of Mitigation Services
(NCDMS) with all comments generated by the North Carolina Interagency Review Team
(NCIRT) during the 30-day comment period for the Lyon Hills Draft Mitigation Plan, which closed
on May 24, 2020. These comments are attached for your review.
Based on our review of these comments, we have determined that no major concerns
have been identified with the Draft Mitigation Plan, which is considered approved with this
correspondence. However, several minor issues were identified, as described in the attached
comment memo, which must be addressed in the Final Mitigation Plan.
The Final Mitigation Plan is to be submitted with the Preconstruction Notification (PCN)
Application for Nationwide permit approval of the project along with a copy of this letter. Issues
identified above must be addressed in the Final Mitigation Plan. All changes made to the Final
Mitigation Plan should be summarized in an errata sheet included at the beginning of the
document. If it is determined that the project does not require a Department of the Army permit,
you must still provide a copy of the Final Mitigation Plan, along with a copy of this letter, to the
appropriate USACE field office at least 30 days in advance of beginning construction of the
project. Please note that this approval does not preclude the inclusion of permit conditions in
the permit authorization for the project, particularly if issues mentioned above are not
satisfactorily addressed. Additionally, this letter provides initial approval for the Mitigation Plan,
but this does not guarantee that the project will generate the requested amount of mitigation
credit. As you are aware, unforeseen issues may arise during construction or monitoring of the
project that may require maintenance or reconstruction that may lead to reduced credit.

Thank you for your prompt attention to this matter, and if you have any questions
regarding this letter, the mitigation plan review process, or the requirements of the Mitigation
Rule, please call me at 919-554-4884, ext 60.
Sincerely,
Digitally signed by
BROWN ING•KIMBERLY• BROWNING.KIMBERLY.DANIELLE.
DAN I ELLE.1527683510 1527683510
Date: 2020.07.14 13:15:55-04'00'
Kim Browning
Mitigation Project Manager
for Tyler Crumbley
Enclosures
Electronic Copies Furnished:
NCIRT Distribution List
Kelly Phillips, Paul Wiesner—DMS
Jeff Keaton—WEI