Juniper Tract Draft Mit Plan comment memo_LMG References

DEPARTMENT OF THE ARMY
WILMINGTON DISTRICT, CORPS OF ENGINEERS
69 DARLINGTON AVENUE
WILMINGTON, NORTH CAROLINA 28403-1343
June 8, 2021
CESAW-RG/Jessop
MEMORANDUM FOR RECORD
Action ID: SAW-2019-01067 Lower Cape Fear Umbrella Bank - Juniper Tract
SUBJECT: Juniper Tract Draft Mitigation Plan IRTComment Memo
NC Division of Water Resources Comments (Erin Davis):
1. Page 10, Section 4.13— Is it possible to narrow down the year of the "recent thinning" activity?
Or at least before X year based on available aerials? Also, cant his area please be called out on
the existing conditions figure. (Similar request for "recent clear cut" activity mentioned on page
19 and "recently logged" area mentioned on page 25.) pp• 10, 19, 25; Fig. 9
2. Page 20, Table 1— Please confirm the proposed entrenchment value is accurate.
Confirmed. The entrenchment value is correct.
3. Page 26, Section 6.A.2— Please include the proposed native riparian seed mix. (Similar request
for native wetland seed mix under Section 6.B.3.) pp. 27, 34
4. Page27, Section 6.13.1—DWR appreciates that site -specific baseline groundwater data was
collected. Please indicate whether 2019 was a "typical rainfall year". p.28
5. Page28, Section 6.13.1—Please confirm the "wetland hydrologic criterion" references the
proposed mitigation credit hydroperiod not just the minimal jurisdictional hydroperiod. The
difference between a 5% and 12% hydroperiod goal may lead to different results on the
effective drainage ditch fill depth. p.29, App. F
6. Page 29, Section 6.13.2— DWR is concerned with the proposed headwater streams having
watersheds as small as 39 acres being at risk for maintaining flow and bed and bank features
and end up trending more towards a wetland feature. See note at end of comments.
7. Page 36, Section 7 —
a. Quantitative data should alsoinclude surfaceflow data for headwatervalley and single -
thread stream reaches. p• 39
b. DWR requests redline as -built drawings identifying any construction deviations from the
approved mitigation plan, including any changes in planted species and quantities.

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8. Page 39 —To be consistent with the 2016 IRTGuidance, DWR recommends a March 151 growing
season start date for the wetland hydrology success criterion. However, we encourage LMG to
collect February groundwater data for potential monitoring report discussion.
p. 41; This has been resolved in discussions with USACE (Jordan Jessop and Mickey Sugg).
9. Page 40 — DWR supports the requested exception to the 2% vegetative monitoring area
requirement based on the site size and uniformity within proposed community types.
10. Page 45, Table 10 —Is fencing proposed for this site? If not, please update with signage damage.
p. 47; Table 13
11. Page 57, Section 9.C—A copy of the draft conservation agreement, preliminaryacceptance
letter by the proposed easement holder and proposed endowment/long-term management
costs were not included in the appendices for I RT review. Please confirm these items will be
included in the Final Mitigation Plan. Are any deviations to the 2020 USACE conservation
easement agreement template language anticipated? p•60
12. Figures— Please confirm that the proposed Mitigation Bank Boundary is consistent with the
proposed conservation easement boundary. Any proposed external easement breaks should not
be included within the bank boundary (e.g. utility easements). Please clearlycall out any roads
and/or trails that are proposed to remain (or be added) within the conservation easement.
Figs. 1-15
13. Figures 1-4— It was initially very confusing having two boundary legend items considering
Juniper Tract is identified in the mitigation plan as the name of the Mitigation Bank.
Additionally, the boundaries appear to overlap except in the northern area. Since the Tax Parcel
Boundary is identified on Figure 4 and it provides better visibility of where the parcel and bank
boundaries overlap, DWR requests that the Tract Boundary be removed from the other figures.
Figs. 1-15
14. Figure 4 & Appendix D aerials — Should the "Site" call out reference the tax parcel or mitigation
bank boundary?
Fig. 4, App. D
15. Figure 12 — DWR requests two additional wetland restoration wells adjacent to the first order
stream restoration reach.
Fig. 13
16. Watershed delineation figure — Apologies if I missed this information, but please make sure to
include a figure showing the watershed a real associated with UT1, UT2 a nd H ickma n Bra nch
restoration reaches (39 acres, 275 acres, etc.).
App. L
17. Appendix E — Please in a location map for the included eight boring logs representative of the
530 acres of wetland credit area. For future reference, DWR has been requesting that the soil
investigation map include all soil check points to capturethe full field assessment effort, notjust
the subset of representative boring log (and photo) points.
App. E
18. Appendix G — DWR requests a summarytable of the well data growing season hydroperiods %.
App. G

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19. Sheet 1—The legend includes a proposed ford crossing icon. I didn't see this feature on the plan
view sheets, please confirm whether ford crossings are proposed for this site. If so, please
include a typical detail for this feature.
App. L - The symbology for a ford crossing has been removed from all plansheets.
20. Sheet 2B—The plan view sheets do not include call out locations for the floodplain interceptor.
DWR is concerned with hardening of the restored stream banks. Please consider alternative
bank stabilization options before placing riprap. Any areas where riprap is installed during
construction should be identified on the as -built drawings.
Understood.
21. Sheets 9, 11 & 13 — Please confirm whetherthe requested strea m credit extends through the
proposed 50-100' rock channels on UT1, UT2 and Hickman Branch. DWR does not support
issuing stream restoration credit for proposed rock channels.
All corresponding text, figs. and appendices have been updated to show credits do not include
ck ram s.
22. DV�/�t encourpages adding more woody material tostream and wetland credit areas as habitat
enhancement features (e.g. woody riffles, tree throws).
Understood.
U.S. Army Corps ofEngineers Comments (Casey Haywood):
1. Pleaseconfirm thatyou are measuring the headwater valley by the centerofthe valley, in a
sthhraight line. Credit must be calculated usingvalley length, not stream centerline measurements.
The prroposbedizero ordersstre�aam crtedits nave Been ca�cuMbd based on the zero -order stream corridor
2. Itewoull(T ele'lcpTulsts�aodnd a no e ins Sec ion C� anKL reedi eDeteSrrriination and Use: that wetland
credit proposed in conjunction with the zero order stream project, was not generated within the
100-ft corridor where the stream is expected to develop. It looks like this area was indicated on
the maps as "zeroorder stream corridor". This could also be annotated on Table 11.
p. 51; Table 14
3. Figure 12: Wetland gauges appearto be in clusters of small transects. Please note that wetland
gauges should be an accurate representation of the different soils, topographic variations, and
vegetation communities on the site. Gauges should also be placed at the center and edges of the
wetlands.
Fig. 13
4. Figure 13 indicates the zeroorder stream corridor as 8 acres; however, the other maps indicate
the area as 7.8acres. Please update
Fig. 14
5. Please include more discussion on grading depths in the Proposed Grading section.
p. 30
6. February 15t is not appropriate for the start of the growing season and should occur no earlier
than March 15t
p. 41; This has been resolved in discussions with USACE (Jordan Jessop and Mickey Sugg).
U.S. Army Corps ofEngineers Comments (Jordan Jessop):
1. Regarding the selected pine removal in the southwest wetland area (discussed on page
34 of the draft mitigation plan), will there be any plantings done in these areas?
The selected pine removal has been removed from the Mitigation Plan.

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2. Are there any concerns about soil constraints (such as compaction, low -quality soil
conditions) in the borrow pit area that will be planted as a basin cypress wetland, which
may impact planting success?
The borrow pit planting has been removed from the Mitigation Plan.
3. The proposed restored riparian wetland area is mapped as Murville, please revise the
proposed hydroperiod performance standard to 16% for this area.
See email sent to Jordan Aug. 26, 2021: The riparian wetland is mapped as Pantego on the NRCS soil
survey. Nick Howell, our licensed soil scientist, mapped the area as Kinston. Pantego has a suggested
Wetland Saturation Range of 12-16% in the table from the 2016 guidance. Kinston is not listed but is
taxonomically most similar to Chastain, which also has a suggested range of 12-16%. Therefore, we
believe that our current proposed criterion of 14% is appropriate
Comment 6: As discussed in Section 6.13.1, it is not anticipated that that the zero -order streams will have defined
bed and bank features. Zero -order stream restoration will be accomplished by re-establishing shallow, linear valleys
which will direct sheet flow toward the first order, single -thread streams. The valleys will also be contoured to
maintain positive drainage to prevent backwater or ponding characteristic of a linear wetland. It is also worth
noting that LMG has identified zero -order reference reaches that have contributing drainage areas as low as 20
acres.