20071843 Ver 1_Corps of Engineer Correspondence_20150720

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DEPARTMENT OF THE ARMY
WILMINGTON DISTRICT, CORPS OF ENGINEERS JUL D
69 DARLINGTON AVENUE 2 U 2015
WILMINGTON, NORTH CAROLINA 28403 -1343
DENR - WATER RESOURCES
TRANSPORTATION PERMITTING UNIT
REPLY EN ION OF: July 16, 2015
Regulatory Division
Action ID. SAW - 2003 -00682
Mr. DeCarol Williamson and
Ms. LaDane- Williamson
Stone Farm Investment, LLC
11 Causeway Drive
Ocean Isle Beach, North Carolina 28469
Dear Sir and Madame:
This letter serves to confirm the Corps' evaluation, in coordination with the Interagency
Review Team (IRT), of the May 2014 Year 2 and May 2015 Year-3 annual monitoring reports ,
for Phase II & III of Stone Farm Mitigation Bank (Bank) located north of Georgetown Road (SR
1163) and east of Seaside Road (SR 1165), adjacent to the Little Caw Caw Canal /Creek and
Drowned Bay, east of Calabash, Brunswick County, North Carolina. Please reference the 5th
January 2009 executed Mitigation Banking Instrument (MBI), the 10th October 2013 executed
Amendment to the MBI, and our May 8, 2013 evaluation letter of the Year 1 monitoring report.
Also, reference my July 9, 2015 onsite inspection 'with Mr. Wes Fryar of Land Management
Group and Ms. Emily Greer of our office.
Phase II (Year 2 and Year 3):
The overall review of the vegetation data shows that Phase II is meeting the performance
standards. However, there are a few of the vegetation plots that cause some concerns. Out of the
29 plots, Plots 2, 8, and 17 failed to satisfy the success criteria regarding single volunteer species
not comprising of more than 50% of the total composition at year 2 or 3. In addition to this, Plot
3, 8, and 17 displays a survival rate of 53 %, 60 %, and 59 %, respectively, at the end of year three.
During the onsite inspection, it was observed that there were sections along the upper portion of
the Main Stem that exhibit sparse vegetative cover, likely due to type of soil, construction
compaction, and the absence of topsoil being brought in prior to planting. It is_ noted that the
vegetation'that is present within these areas, excluding the planted stems, are species that favor
wetter environments. At this time, no recommendations or remedial actions are being made for
these areas. Our office will continue to monitor the progress of these areas. For future
monitoring reports, please provide the original, or as= built, planted stem counts in the total
columns for each plot in Table 4. This allows for a quick survival rate calculation of the entire
plot. It is noted that Table 4C includes the total as -built number for each tree species, which does
provide value in determining the survival rate for each species type in each plot.

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In review of the hydrology data, our office concurs that all (14) of the wells in Phase II
have met the success criteria, noting that the initial concerns with Well 12 have been nullified
with the results of replacement Well 12 (Pairing). Our office also agrees with the provided
stream data results, summarized in Table 8 of Year 2 and 3 reports, demonstrating the bankfiill
events occurring within normal and above normal conditions throughout 2013 and 2014. The
requested additional information in the May 8, 2013 letter greatly assisted in our evaluation of
the streams conditions and level of function. One requested addition to this information is the
inclusion, or overlay, of the As -built stream profile in the "Cross Section" drawing: This will
help the IRT to observe any changes overtime and to determine the magnitude or significance of
those changes. In evaluating the stream data, there were significant differences between Year 2
and 3 reports in the data listed under `Bankfull Dimensions ". For example, the Year 2 report has
the bankfull width at 47.5 feet and the width -depth ratio at 44.0 for Mainstem 1, while Year 3
shows a width of 17.8 feet and the width -depth ratio at 8.0. These differences are shown on
several the streams and their reaches. Please provide an explanation of these differences and/or
if there were changes in the calculation of this data.
In the overall evaluation of Year 2 and Year 3 monitoring information for Phase II, the
Corps has determined that the vegetation and hydrology performance standards have been met
and the combined scheduled credits (30 %, or 58.6 wetland credits and 3,068 stream credits) for
both monitoring years are therefore released. The combined credits, under Task 3.2 and 3.3 as
depicted in Tables 3b, 3c, and 3d of the Amended MBI, comprise of 31.4 riparian (non - riverine)
wetland credits, 27.3 non - riparian wetland credits and 3,068 linear feet of stream credits.
To date, the cumulative total of credits released for Phase II is the following: 73.1 riparian
(non - riverine) wetland credits, 63.5 non - riparian wetland credits, and 9,203 linear feet of stream
credits.
Phase III:
The Corps acknowledges the overall hydrology improvements for Wells 5, 6, and 7 above
Plug 92 and concurs that all three, including Wells 1, 2, and 3, have met the success criteria
under normal conditions for the 2013 and 2014 monitoring years. However, our office has
continuing concerns with the performance of Well 8 since the first year of monitoring. For years
two and three, the only times of the growing season Well 8 met the full 32 day performance
standard was during above normal rainfall periods. Please be reminded that the criteria of 12
percent of the growing season are for "under periods of normal rainfall ". Additionally, the peak
periods coinciding with heavy rainfall events displayed rather sharp declines, especially when
compared to other well responses during the same event. The results of Well 8 appear to reflect
some drainage influence from the 3.5 to 4.0 -foot deep ditch that is located within approximately
75 feet of its location. The mitigation area surrounding Well 8 is designated as a combination of

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enhancement and preservation and encompasses approximately 15 acres. During the onsite
inspection, it was observed that the ordinary high water mark along the ditch bank was over 2.0
feet below the adjacent ground elevations, which is likely to reflect a drainage influence within
the location of the well. For this area, our office recommends two options: (1) initiate
modifications, such as installing ditch plugs or backfilling the majority of the ditch, in order to ,
increase the area's ability to retain additional hydrology, or (2) recalculate, with input from the
Corps and IRT, the credit types and amounts based on the drainage influence from the ditch. The
other option is continue to monitor the area to observe how the well responses in year 4 and 5.
Please provide our =office with any corrective plans or contact our- office for further consideration..
on options in this area.
Additionally for Phase 111, the July 9th inspection revealed that Plug #1 continues to show
signs of erosion along its northern bank within the area noted during my November 7, 2013
onsite inspection with Land Management Group. This on -going erosion has serious long -term
potential to increase head - cutting in the ditch plug and/or within4he adjacent targeted wetland
restoration, which would compromise the mitigation area. It is strongly recommended that
corrective or remedial measures to secure and stabilize Plug## 1 and its bank from any additional
erosion needs to be implement as early as possible. Please be aware that '. failure to provide long-
term stability in this area may result in the withholding of,fulre credits.'
Based on Year 2 and 3 results for Phase IIl, it has been determined that 25% (or 21.25
credits) of the available 30% combined non - riparian wetland credits, as depicted in Task 3.2 and
3.3 of Table 3e in the Amended MBI, are released for compensatory mitigation use. The
remaining 5% (or 4.25 credits) will continue to be withheld based on the uncertainty of the area
surrounding Well 8 and its success to retain the appropriate levels of hydrology during normal
rainfall periods.
With the Year 2 and 3 combined 25% credit release, Phase III's cumulative total released
to date is 55.25 non - riparian wetland credits.

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Please be reminded of your obligations pursuant to the 10th October 2013 Amendment to
the MBI, which includes the submittal of a debit ledger within 30 days from the final sell of any
credit; and to continue maintenance inspections throughout the bank in order to evaluate the
condition and stability of all earthen plugs and in- stream structures. Should you have any
questions, please do not hesitate to contact me at telephone [phone].
Sincerely,
Mickey Sugg, Project Manager
ington Regulatory Field Officc
Copies Furnished: .
Mr. DeCarol Williamson
Stone Farm Investment, LLC
2618 New Village Way
Wilmington, North Carolina 28405
Ms. Ladane Williamson
Ocean Isle Investment Co.
11 Causeway Drive
Ocean Isle, North Carolina 28469
Mr. Christian Preziosi
Land Management Group, Inc.
3805 Wrightsville Avenue, Suite 15
Wilmington, North Carolina 28403
Ms. Maria Dunn
North Carolina Wildlife Resources
Commission
943 Washington Square Mall
Wilmington, North Carolina 27889
Ms. Cyndi Karoly
Division of Water Resources -
North Carolina Department of Environment
and Natural Resources
Program Development Unit
1617 Mail Service Center
Raleigh, North Carolina 27699 -1617
Mr. Fritz Rohde
National Marine Fisheries Service
Pivers Island
Beaufort, North Carolina 28516
Ms. Kathy Matthews
U.S. Fish and Wildlife Service
Fish and Wildlife Enhancement
Post Office Box 33726
Raleigh North Carolina 27636 -3726

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Mr. Todd Bowers
U.S. Environmental Protection Agency
Wetlands Regulatory Section- Region IV
61 Forsyth Street, S.W.
Atlanta, Georgia 30303 -8960
Ms. Debbie Wilson
North Carolina Division of
Coastal Management -
127 Cardinal Drive Extension
Wilmington North Carolina 28405 -3845
Ms. Holly Snider
North Carolina Division of
Coastal Management
127 Cardinal Drive Extension
Wilmington North Carolina 28405 -3845
Ms. Chad Coburn
Division of Water Quality
North Carolina Department of Environment,
and Natural Resources
127 Cardinal Drive Extension
Wilmington, North Carolina 28405
Mr. Travis Wilson
North Carolina Wildlife Resource
Commission
1718 Highway 56 West
Creedmoor, North Carolina 27522
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