20081317 Ver 1__20160314

FIFTH ANNUAL (2014) AND SUMMARY REPORT FOR THE
HELL SWAMP/SCOTT CREEK WATERSHED MITIGATION SITE
PANTEGO TOWNSHIP BEAUFORT COUNTY, NORTH CAROLINA
Prepared for:
PCS Phosphate Company, Inc.
Prepared by:
CZR Incorporated
February 2016

FIFTH ANNUAL (2014) AND SUMMARY REPORT FOR THE
HELL SWAMP/SCOTT CREEK WATERSHED MITIGATION SITE
PANTEGO TOWNSHIP
BEAUFORT COUNTY, NORTH CAROLINA
Prepared for:
PCS Phosphate Company, Inc.
Prepared by:
CZR Incorporated
February 2016

TABLE OF CONTENTS
1.0 PROJECT OVERVIEW..................................................................................................
1.1 History ...............................................................................................................
1.2 Location.............................................................................................................
1.3 Goals and Performance Criteria........................................................................
2.0 REQUIREMENTS..........................................................................................................
2.1 Normal Rainfall and Growing Season...............................................................
2.2 Hydrology..........................................................................................................
2.3 Vegetation.........................................................................................................
2.4 Hydrogeomorphic Monitoring of Streams and Valleys ......................................
2.6 Photographic Documentation............................................................................
3.0 SUMMARY RESULTS BY PARAMETER.....................................................................
3.1 Rainfall..............................................................................................................
3.2 Hydrology..........................................................................................................
3.2.1 QA/QC of Well Performance..........................................................................
3.2.2 Geomorphic Monitoring, Flow Events, and Annual Stream and Headwater
ValleySurveys................................................................................................
3.2.3 Hydroperiods..................................................................................................
3.2.3.1 Riparian Headwater Systems/Bottomlands............................................
3.2.3.2 Non -riparian Hardwood Flat....................................................................
3.2.4 Hydroperiod Comparison to Control Forests ..................................................
3.2.4.1 Plum's Pit...............................................................................................
3.2.4.2 Windley Tract..........................................................................................
3.2.4.3 Winfield Tract..........................................................................................
3.3 Vegetation.........................................................................................................
3.3.1 Tar Pamlico Riparian Buffer Areas.................................................................
3.3.2 All Vegetation Plots.........................................................................................
3.3.4 Volunteer Woody Vegetation..........................................................................
3.3.4.1 Tar -Pamlico Riparian Buffer...................................................................
3.3.4.2 All Vegetation Plots.................................................................................
3.4 Photographic Documentation............................................................................
4.0 MONITORING SUMMARY............................................................................................
4.1 Hydrology.................................................................................................................
4.3 Stream Flow and Consolidated Tar -Pamlico Buffers ...............................................
4.4 Vegetation................................................................................................................
5.0 SITE CLOSE OUT SUMMARY.....................................................................................
LITERATURE CITED...................................................................................................................
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Cover Photos: Top photo -view to the south showing proximity of site to Scott and Smith Creeks,
August 2014. Bottom photo -view to the north, showing several stream features
on the site, February 2014.
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Fifth Annual and Summary Report February 2016

LIST OF FIGURES
Figure 1 Hell Swamp Vicinity Map
Figure 2 Hell Swamp Monitoring Locations
Figure 3 Hell Swamp Mitigation Site Monitoring Locations on Soil Survey
Figure 4A Hell Swamp Restoration Area Well Locations on As Built LiDAR
Hell Swamp/Scott Creek Mitigation Site iii PCS Phosphate Company, Inc.
Fifth Annual and Summary Report February 2016
LIST OF TABLES
Table 1
Performance criteria, methods summary, and current status .....................................
T-1
Table 2a
Summary of monthly visual observations of flow in 2014 from upper Scott
Creek and its headwater systems (UT1 — UT7) and a tributary to Smith
Creek (UT8) at Hell Swamp........................................................................................T-4
Table 2b
Summary of visual observations of flow in 2014 from Bay City, Scarp,
Porter Creek, and Duck Creek....................................................................................
T-5
Table 3a
Wetland hydroperiods in 2014 of 94 riparian monitoring wells at Hell
Swamp restoration site during all rainfall conditions ...................................................
T-6
Table 3b
Wetland hydroperiods in 2014 of 110 non -riparian hardwood flat monitoring
wells at Hell Swamp restoration site and 14 nearby control wells during all
rainfallconditions......................................................................................................
T-17
Table 4a
Wetland hydroperiods in 2014 of 94 riparian monitoring wells at Hell
Swamp restoration site during WETS normal and below normal rainfall
conditions..................................................................................................................
T-30
Table 4b
Wetland hydroperiods in 2014 of 110 non -riparian hardwood flat monitoring
wells at Hell Swamp restoration site and 14 nearby control wells during
WETS normal and below normal rainfall conditions.................................................T-41
Table 5
Fifth annual (2014) survival of trees and shrubs planted in 123 0.22 -acre plots
and 19 0.017 -acre riparian buffer plots at Hell Swamp and volunteer
woody wetland stems counted in those plots in 2014 ..............................................T-54
Table 6
Survival of trees and shrubs by species planted in 19 0.017 -acre plots in
0 -50 -foot riparian buffer at Hell Swamp from baseline to fall 2014 ...........................
T-55
Table 7
Survival of trees and shrubs by species planted in 14 riparian 0.22 -acre
plots at Hell Swamp from baseline to fall 2014.........................................................T-56
Table 8
Survival of trees and shrubs by species planted in 109 0.22 -acre plots at
Hell Swamp from baseline to fall 2014.....................................................................T-57
Table 9
Survival of trees and shrubs by species planted in all 123 0.22 -acre plots at
Hell Swamp from baseline to fall 2014.....................................................................
T-58
Table 10
Volunteer woody stems in 142 Hell Swamp vegetation monitoring plots
during the fifth annual survey in 2014.......................................................................
T-59
Table 11 a
Summary of occurrence of wetland hydroperiods and drought status from
2010 to 2014 for riparian wells at Hell Swamp during all rainfall conditions.............T-60
Table 11 b
Summary of occurrence of wetland hydroperiods and drought status from
2010 to 2014 for non -riparian wells at Hell Swamp during all rainfall conditions
.....T-64
Table 12a
Summary of occurrence of wetland hydroperiods and drought status from
2010 to 2014 for riparian wells at Hell Swamp during WETS normal and
below- normal rainfall conditions..............................................................................T-69
Table 12b
Summary of occurrence of wetland hydroperiods and drought status from
2010 to 2014 for non -riparian wells at Hell Swamp during WETS normal
and below -normal rainfall conditions........................................................................T-73
Table 13
Summary of occurrence of hydroperiods, PDSI and PHDI drought status,
soil profiles for 23 wells at Hell Swamp that met the hydrology restoration
criterion 2010-2014, one well that met the criterion when 2015 data are
included, and were all shown as underlain by non -hydric soils on Beaufort
Countysoil survey.....................................................................................................T-78
Table 14
Summary of flow events recorded during monthly site visits from 2011 to April
2015 at Hell Swamp flow monitoring stations...........................................................T-82
Table 15
Numbers and species of woody stems counted in four Tar -Pamlico
riparian buffer plots in the unconstructed lower UT6 stream valley flow way ...........
T-83
LIST OF FIGURES
Figure 1 Hell Swamp Vicinity Map
Figure 2 Hell Swamp Monitoring Locations
Figure 3 Hell Swamp Mitigation Site Monitoring Locations on Soil Survey
Figure 4A Hell Swamp Restoration Area Well Locations on As Built LiDAR
Hell Swamp/Scott Creek Mitigation Site iii PCS Phosphate Company, Inc.
Fifth Annual and Summary Report February 2016

Figure 4B
Hell Swamp Control Forest Well Locations on 2004 LiDAR
Figure 5
2014 Hell Swamp and WETS Rainfall
Figure 6
Hell Swamp Mitigation Site Monitoring Wells -2014 Longest Hydroperiods and
Estimated Hydrologic Zones During All Rainfall Conditions
Figure 7
Hell Swamp Mitigation Site Monitoring Wells -2014 Longest Hydroperiods and
Estimated Hydrologic Zones During WETS Normal and Below Normal Rainfall
Conditions
Figure 8
Pine Removal at Hell Swamp Mitigation Site in 2014
Figure 9
Hell Swamp Jurisdictional Areas Prior to Construction
Figure 10
Hell Swamp Annual Rainfall Compared to WETS Aurora
Figure 11
Hell Swamp Well Locations on Mapped Non -hydric Soils
Figure 12A
Hell Swamp Mitigation Site Riparian Buffer Zones under Consolidated Tar Pamlico
Buffer Rule on Aerial Photograph
Figure 12B
Hell Swamp Mitigation Site Riparian Buffer Zones under Consolidated Tar Pamlico
Buffer Rule
Figure 13
Proposed Mitigation Yield for Hell Swamp/Scott Creek Mitigation Site
APPENDICES
A 2014 Hydrogeomorphic Stream Surveys and Cross Section Measurements
B Flow Summary (final stream surveys and 2010-2015 observations [videos on thumb drive
only])
C Stem Counts All Plots and Lower UT6 Buffer Plot Data
D Selected Fifth Annual (2014) Restoration Site Photographs
E 2015-2016 Soil Profile Photographs (thumb drive only)
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Fifth Annual and Summary Report February 2016

1.0 PROJECT OVERVIEW
1.1 History. The 1,297 -acre Hell Swamp/Scott Creek Watershed mitigation site is a
significant component of the compensatory mitigation for unavoidable impacts to wetlands and
waters as authorized by Section 404 Permit Action ID 200110096 and the Section 401 Water
Quality Certification DWQ #2008-0868, version 2.0. CZR Incorporated (CZR) of Wilmington, NC
monitors hydrology and vegetation of the Hell Swamp site, as well as three other nearby sites
(Windley, Plum's Pit, and Winfield) used as hydrological controls. Hydrogeomorphic monitoring
of the stream valleys is conducted by Baker Engineering. Restoration activities at Hell Swamp
were authorized by the NC Division of Coastal Management and Coastal Area Management Act
(CAMA) major development permit 83-09 as well as the NC Division of Land Resources Erosion
and Sediment Control Permits, which were issued for 11 separate phases and further described
in the As Built Report (CZR 2010) and the Baseline and First Annual Report (CZR 2011). Work
occurred from 1 July 2009 until 22 June 2010 and began in areas not subject to CAMA or Section
404 jurisdiction. Planting occurred from February to May 2010, after each phase of restoration
earthwork was completed; planted species and densities are described in CZR 2010.
1.2 Location. The Hell Swamp site is located within the Pamlico Hydrologic Unit
03020104 of the Tar -Pamlico river basin within the Pungo Creek subbasin and encompasses
almost the entire Scott Creek watershed and a portion of the watersheds of Smith Creek and
Broad Creek. Located on the southwest side of Seed Tick Neck Road (SR 1714) in Beaufort
County, the site is approximately 2 miles east-southeast (straight-line distance) of the town of
Yeatesville, Pantego Township, North Carolina (Figure 1).
1.3 Goals and Performance Criteria. The primary goal of the project was to restore a
self-sustaining functional watershed and wetland/stream complex to allow surface flow to move
through vegetated wetlands before reaching any stream. Mitigation yields are estimated and
performance criteria are described for the project in detail in the Compensatory Mitigation Plan for
Restoration of Hell Swamp/Scott Creek Watershed (CZR 2009). Performance criteria and current
status are summarized in Table 1. Over time the Hell Swamp site was expected to successfully:
reestablish approximately:
• 19,783 linear feet (LF) of zero and first -order stream, including the
restoration of six riparian headwater systems and three low energy
streams;
• 21 acres of Tar -Pamlico riparian buffer
• 58 acres of riparian forested hardwood wetland (headwater forest,
bottomland hardwood forest and riverine swamp forest), with some
additional enhancement potential; and
• 808 acres of non-riverine hardwood flat; and
preserve or rehabilitate approximately:
• 40 acres of non-riverine hardwood flat including a 34 -acre "state or
regionally significant" mature hardwood flat;
• 28 acres of riverine swamp forest/bottomland hardwood forest;
• 18 acres of non-riverine hardwood flat; and
• 200 acres of areas mapped as uplands on the county soil survey.
An additional 103 acres underlain by hydric soils were included as "potential non -
wetland" areas due to drainage effects from perimeter ditches that must remain open.
Approximately 34 acres at the head of the Scott Creek watershed is mature non-riverine wet
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Fifth Annual and Summary Report February 2016

hardwood forest underlain by Cape Fear soil (the Windley tract) and preserved to help mitigate
for permitted mine impacts to the Bonnerton non-riverine wet hardwood area. The Plum's Pit
tract (Arapahoe soil, hardwood forested wetland) and the Winfield tract (Augusta, Tomotley, and
Roanoke soils) are other nearby hardwood forested wetlands at similar elevations to portions of
Hell Swamp and underlain by soil series mapped on Hell Swamp as shown on the Beaufort
County Soil Survey (Kirby 1995). All three tracts were monitored as hydrologic controls for the
restored hydrology of applicable areas at the Hell Swamp site (Figure 1).
2.0 REQUIREMENTS
2.1 Normal Rainfall and Growing Season. An onsite continuous electronic rain
gauge is downloaded once a month and its data are used in conjunction with data from nearby
automated weather stations (i.e., NOAA's Aurora site because the Belhaven site was not active in
2014) to determine normal rainfall during the monitoring period. Hell Swamp data were
compared to the WETS range of normal precipitation to determine if Hell Swamp rainfall was
within the normal range. The WETS data "define the normal range for monthly precipitation and
normal range for growing season required to assess the climatic characteristics for a geographic
area over a representative time period" and come from National Weather Service Cooperative
Network stations (http://www.wcc.nres.usda.gov/climate/wets doc.html, accessed 30 March,
2015). The range of normal precipitation for this report refers to the 30th and 70th percentile
thresholds of the probability of having onsite rainfall amounts less than or higher than those
thresholds. The range of normal and the 30 -day rolling total data lines begin on the last day of
each month and the 2014 WETS -Aurora monthly precipitation total is plotted on the last day of
each month. The WETS data includes 30 years of historical rainfall data.
Under the 2010 regional guidance from the Corps of Engineers for wetland hydroperiods,
the normal growing season for Beaufort County is 28 February to 6 December or 282 days
(WETS table for Beaufort County first/last freeze date 28° F 50 percent probability) (US Army
Corps of Engineers 2010). At the suggestion of the Corps' Washington regulatory field office,
data collected between 1 February and 28 February provide important information related to
analyses of site hydrology during the early growing season, but are not part of the hydroperiod
calculation for success.
2.2 Hydrology. Figure 2 depicts the locations of hydrology monitoring equipment. All
well locations are also depicted on the Beaufort County Soil Survey sheet 9 (Figure 3) and on
LiDAR (Figures 4A and 4B). To document surface storage, hydrology in the restored riparian
headwater system, and hydroperiods of all wetland types on the site, 110 semi -continuous
electronic Ecotone water level monitoring wells (manufactured by Remote Data Systems, Inc. or
RDS) were deployed at a density of approximately 1 well/10 acres in the non -riparian wetland flat
areas at the start of the 2010 growing season. An additional 14 wells within the expected riparian
zone (installed at the start of the 2010 growing season) and 80 wells in 40 arrays across the
stream valleys measure the hydrology of the riparian stream systems and bottomlands (94
riparian wells). The 80 wells were installed throughout the 2010 growing season, and therefore,
many did not record spring wetland hydroperiods that year. Forty (40) gauges (beta models) to
record low flow events were also installed either within or near each of these stream arrays in
early 2011. However, the flow gauges were removed in 2013 due to a decrease in reliability, but
monthly visits to the arrays continued. Each stream valley array consisted of a well on either side
of the perceived valley and a flow gauge in the valley where flow had been evident or seemed
likely based on the topography of the valley and surrounding area. The arrays are approximately
500 feet apart (along the long axis) in each valley (at least 3 arrays per 1,000 -foot reach;
upstream, center, downstream). Observations at the site of the flow gauge during well downloads
and semi-annual stream surveys, rainfall, and geomorphic position are used to document
evidence of flow.
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At the longest monitored control site (Windley tract), three electronic wells, each paired
with a manual well, have been monitored since March 2007. Four electronic wells have been
monitored in Plum's Pit since October 2010 and seven electronic wells have been monitored in
the Winfield tract since July 2011 (Figures 3 and 4B).
Electronic wells are downloaded once a month and the data (readings every 1.5 hours)
evaluated on an annual basis to document wetland hydroperiods. Wetland hydroperiods are
calculated by counting consecutive days with water level at least 12 inches below the soil surface
during the growing season under normal or below normal rainfall conditions. Data from the
Windley, Plum's Pit, and Winfield sites are used to compare to hydrology at applicable areas at
Hell Swamp. Because of differences in maturity and disturbance characteristics of the mitigation
site, these data will not be used for strict success or performance parameters, only to confirm
local/regional hydrological response to precipitation. Visual observations of flow conditions at the
valley arrays are recorded. No control site for the flow parameter has been identified, although
observational data from another nearby PCS mitigation site (Bay City) and from other sites
monitored for other PCS projects (Scarp, Porter Creek, and Duck Creek) are included with this
report to show how other sites functioned during the year.
2.3 Vegetation. The fifth annual survey of the 123 0.22 -acre planted tree and shrub
monitoring plots occurred in October and November 2014 and represents a 2 percent sample of
the restoration area (Figure 2). Smaller (0.017 -acre) planted tree and shrub monitoring plots
were also surveyed at 19 stream arrays to provide an estimate of stem density in the potential
riparian buffer areas. (Under the new consolidated riparian buffer rules, some of the 123
vegetation plots will also serve to demonstrate stem density in the areas of expanded buffer width
allowed under the new rule.) Annual monitoring for three nuisance species [red maple (Acer
rubrum), sweet gum (Liquidambar styraciflua), and loblolly pine (Pinus taeda)] occurred 2011-
2013 and the results are in the yearly reports (CZR 2012, 2013, 2014). In accordance with the
mitigation plan for year 5 (2014), woody volunteer species were also documented in the
vegetation plots during the fall vegetation survey.
2.4 IHydrogeomorphic Monitoring of Streams and Valleys. The headwaters of Scott
Creek, the main drainage that flows through the site, are almost completely contained onsite, and
flow traverses to the downstream extent of the property at NC Route 99, where the creek flows
through a road culvert and eventually discharges to Pungo Creek, a tributary to the Pungo River.
For this report, the main channel is divided into Upper Scott Creek (USC), which contains the
constructed single thread channel and the zero order valley upstream, and Lower Scott Creek
(LSC) which contains the historic swamp never put into agricultural production. Several coastal
plain headwater valleys (UT1 — UT8) were identified, using LiDAR, historical aerials, and
knowledge of the site (Figures 2 and 3). Seven of these valleys are tributaries to Scott Creek and
one is a tributary to Smith Creek (UT8). Two cross sections in the Scott Creek single thread
channel stream segment are measured annually during the monitoring period; cross sections in
the other valleys were measured in the second (2011) and fifth (2015) stream monitoring year.
2.5 New Consolidated Buffer Rules. The NC Environmental Management
Commission (EMC) adopted Rule 15A NCAC 02B .0295, "Mitigation Program Requirements for
the Protection and Maintenance of Riparian Buffers", on 9 May 2013. On 18 July 2013, the Rules
Review Commission (RRC) approved the Rule, however since more than 10 letters of objection
were received, the Rule was sent to the General Assembly. A stakeholder group was formed by
the NC Division of Water Resources (DWR) as requested by the NC Department of Environment
and Natural Resources. The stakeholder group, consisting of members from the NC
Environmental Restoration Association, PCS Phosphate Company, Inc. NC Department of
Transportation, NC Ecosystem Enhancement Program, and DWR, met several times during late
2013 and early 2014, came to a consensus, and provided buffer rule recommendations in a
stakeholder report released 10 April 2014. Section 1 of Session Law 2014-95 disapproved the
rule adopted by the EMC and stated that a temporary rule should be passed by the EMC that was
mostly identical to recommended rules offered in the stakeholder report. The EMC began
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Fifth Annual and Summary Report February 2016

updating the temporary rule on 14 August 2014 and had a comment period from 14 August to 12
September 2014; a public hearing was held on 28 August 2014. The Temporary Rule 15A NCAC
02B .0295 was adopted on 30 September 2014 and became effective 24 October 2014. The six
previous riparian buffer mitigation rules (15A NCAC 02B .0242, .0244, .0252, .0260, .0268, and
.0609) were repealed since they are proposed to be consolidated and replaced by 15A NCAC
.02B .0295. A public hearing on a permanent rule was held on 12 March 2015 with a comment
period opened until 17 April 2015. The rule became permanent 1 September 2015; however,
buffer mitigation for this project was approved by DWR under the Temporary Rule.
The new consolidated buffer rule allows for mitigation within the same eight -digit HUC at
a 1:1 mitigation ratio or in an adjacent eight -digit HUC at a 2:1 mitigation ratio. The new rule also
allows for alternative buffer mitigation options not included in the previous rule including: coastal
headwater stream/valley mitigation; restoration, enhancement, and preservation of buffers on
non -subject streams; and preservation of buffers on subject streams. In non -urban areas, stream
buffer widths that are wider than 30 feet to 100 feet will be given full credit, while buffers that
extend 100 to 200 feet from the stream will be given 50 percent credit. Vegetation in the buffer
should include 260 stems per acre at monitoring year five with a minimum of four native
hardwood tree species or four native hardwood tree and shrub species; no one species should
account for more than 50 percent of stems. Volunteer native woody stems may be included to
meet the vegetation requirements. Alternative vegetation plans may be approved by DWR after
factors such as site wetness and plant availability are considered. Projects that have been
constructed and are within the required monitoring period on the effective date of the new rule are
eligible for use as alternative buffer mitigation. Buffer mitigation projects that have completed
monitoring and have been released by DWR on or before the effective date of the rule are
acceptable for use as alternative buffer mitigation for 10 years from the effective date of the rule.
Buffer mitigation used for buffer mitigation credit cannot also be used for nutrient offset or wetland
mitigation credits.
2.6 Photographic Documentation. Twenty (20) permanent photo point locations
were established at random well locations and five were established along the perimeter of the
restoration area (Figure 2). Photographs were taken in the four cardinal directions as well as an
additional direction to capture as much of the vegetation plot as possible unless it was already
captured in the other four photos. Photographs at the fixed-point stations were taken in July
2010 (baseline) and each subsequent fall during the monitoring period. Fifth year annual
photographs were taken in November 2014.
3.0 SUMMARY RESULTS BY PARAMETER
3.1 Rainfall. Total rainfall recorded at the Hell Swamp rain gauge for 2014 was
53.07 inches (about 10 inches more than 2013) and total rainfall recorded at the nearby PCS
Duck Creek monitoring site was 43.08 inches (about 7 inches more than 2013). The WETS 30 -
year range of normal data shown on Figure 5 is derived from the latest available data set and
comprises the years 1971-2000. The 30 -day rolling total of Hell Swamp 2014 rainfall was
considered within WETS normal range or below normal for most of the year (Figure 5). However,
rainfall from June 19 to July 31 was substantially higher and was considered above normal.
Wetland hydroperiods were adjusted to exclude those days.
The US Drought Monitor (http://droughtmonitor.unl.edu) provides a synthesis of multiple
indices and impacts and reflects the consensus of federal and academic scientists on regional
conditions on a weekly basis (updated each Thursday). Using an area -weighted average, North
Carolina's Beaufort County experienced abnormally dry drought conditions the last four weeks of
the 2014 growing season.
3.2 Hydrology. The first full year of post -restoration hydrology data for the entire site
was 2011 because construction activities prevented all wells from being installed at the start of
the 2010 growing season. However, wells were installed as soon as construction in an area was
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Fifth Annual and Summary Report February 2016

complete, so data were collected during a large portion of the 2010 growing season over most of
the site. (All but two of the non -riparian wells were installed by the end of March 2010, but only
12 of the riparian wells were installed by then). Tables depicting 2014 daily well readings and
rainfall are included on a companion thumb drive to this report.
3.2.1 QA/QC of Well Performance. In 2011, approximately one third of the
Hell Swamp wells were tested for performance according to monitoring requirements specified in
ERDC TN -WRAP -05-2 (US Army Corps of Engineers 2005). The testing was described in the
second annual (2011) monitoring report (CZR 2012). In 2013, an additional 24 of the untested
wells were tested and all met the performance criteria. No wells were tested in 2014.
3.2.2 Geomorphic Monitoring, Flow Events, and Annual Stream and
Headwater Valley Surveys. Two cross sections (7 and 8) in the single thread channel of upper
Scott Creek were established at baseline and are measured annually. The fifth annual
measurement of those two cross sections occurred in January 2015 and no areas of concern
were identified. Sixteen additional cross-sections (out of the original 34 from the first year) were
surveyed for the fifth year of stream/valley monitoring. Each cross section exhibited minor
differences from as -built conditions, but those differences are expected in newly constructed
restoration sites. Although there have been some notable changes, there are no areas of
concern and the cross-sections appear to be stable. The channel and floodplain changes
observed along the cross sections are attributed to flood deposition, soil settlement, maturation of
vegetation, and slight differences in survey rod point locations. Appendix A contains the
complete Baker geomorphic report, which includes a figure showing the location of all cross
sections and the profiles of each cross section measured in 2015 in addition to previous cross
section depictions.
Monthly observations at flow monitoring stations documented active flow at least
once at 33 of the 40 observation points, which also means active flow was documented
somewhere in every stream or headwater valley in 2014 except for UT2 and UT5 (Table 2a). The
other sites exhibited similar flow events (Table 2b). Photographs and video of flow taken during
monthly site visits are also included only on the companion thumb drive to this report.
The first stream/valley survey occurred 27 January 2011 when each headwater
valley was walked to determine the locations for installation of the low flow gauges. During that
survey, flow of varying amounts and depths was noted in almost all the valleys and at almost
every gauge location. A second stream survey was conducted at the end of the year (30
November — 1 December 2011). Active flow was occurring during the second stream survey at
UT8 and Lower Scott Creek, but was not discernible in other valleys, although water was present.
However, evidence of past flow events was noted during the second stream survey in UT3, UT6,
UT7, UT8, and Upper Scott Creek (sorting, deposition, shallow channel features, debris/wrack,
and braids or meanders). Refer to Appendix B of the second annual report (CZR 2012) for a
summary of the two surveys, selected photos, and map of documented stream features.
For each subsequent survey, all the headwater valleys at Hell Swamp were
walked from the downstream end to the upper reaches to document active flow with video (if
possible), or evidence of past flow with photographs and GPS data. The third and fourth surveys
in 2012 occurred 27 June and 11 and 13 December 2012 and the findings were described in
Appendix B of the third annual report (CZR 2013). Also, video of flow from the December survey
at various locations was included on the companion CD to that report. Active low flow in various
water depths was observed in Lower Scott Creek and portions of Upper Scott Creek (single
thread and above) in both the June and December surveys. During the June survey, no active
flow or water was observed in any of the headwater valleys and no video was taken of Lower or
Upper Scott Creek, as flow was of low velocity and would not be easily seen in a video. The
winter survey occurred over two days in December with nearly 1.5 inches of rainfall occurring
between the two days. The 11 December 2012 survey day was much like the June survey with
the exception of flow video recorded in Lower Scott Creek near the mouth of UT6. There were no
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Fifth Annual and Summary Report February 2016

other observations of active flow or water in any of the other valleys on that day except UT6.
After the 12 December rain event, the stream crossing between Lower Scott Creek and Upper
Scott Creek was revisited on 13 December 2012 and active flow video was recorded. Several
videos of active flow were also recorded for UT8. In addition to active flow, physical features
noted during stream surveys in 2012 included bed and bank, sediment transport and/or scour,
sediment sorting, debris wrack, and matted vegetation parallel to downstream flow.
The fifth and sixth surveys occurred 9-10 July and 10-11 December 2013. Every
valley contained water, even if only confined to its lower end. Active flow in varied water depths
was visible and documented with video in all the headwater valleys with the exception of UT2.
Active flow was documented for the first time in the project's history near the mouth of UT5 during
the December survey. In addition to the 10-11 December survey visit, biologists returned to the
valleys of UT5 and UT6 the following week on December 18 in an attempt to re -acquire flow
video lost due to corrupted files. Flow was documented where conditions were similar to those
during the 10-11 December survey. In addition to active flow, physical features noted during
stream surveys in 2013 included bed and bank, sediment transport and/or scour, sediment
sorting, debris wrack, and matted vegetation parallel to downstream flow.
The seventh survey (fourth year of stream monitoring) occurred 8 October 2014.
As is typical of many stream restoration projects without a tree canopy, over the years of
monitoring, the density and diversity of herbaceous vegetation continued to increase most in the
Hell Swamp coastal plain headwater stream valleys and the single -thread channel of Scott Creek.
Herbaceous vegetation remains sparse in the lowest Scott Creek segment downstream of the
junction with UT6. Some features noted in earlier stream surveys have become more obscure
due to colonization of herbaceous vegetation. The 2014 survey in the upper end of UT3 (the
portion west of constructed stream crossing along old farm road) and UT6, in UT7, and upper
Scott Creek was postponed to February 2015 due to the density of herbaceous vegetation which
made it very difficult to confidently determine evidence of previous flow events.
The most downstream section of lower Scott Creek was in shallow bank full
condition during the October 2014 survey, but flow was low to none; water depths ranged from 3
to 5 inches. The stream crossing along the old farm road at the upstream end of lower Scott
Creek showed no flow where the flow path enters the swamp; water depth was 2 to 3 inches. No
flow or evidence of flow was seen in UT1, UT2, UT4, and UT5. In UT3, narrow flow paths were
visible between 2B and 3B flow gage locations. Between 3B and 5B the flow path continued, but
there was no water or other evidence of flow as in past surveys (no debris packs).
During the February 2015 survey, flow was documented in some of the portions
of UT3 upstream of the stream crossing. In UT6 during the October 2014 survey, video was
taken of flow and characteristics of the narrow persistent channel at the bottom of the stream
valley, just upstream and at the junction with lower Scott Creek swamp and the filled farm ditch.
During the February 2015 survey, flow was documented in most of the upper valley of UT6 and
UT7 and some channel segments were documented in UT6. In UT8, segments of flow and/or
flow paths have been documented at several locations along the valley during every survey,
including the October 2014 survey. Vegetation was growing in the entire length of the single -
thread channel of Scott Creek but in some areas was oriented downstream. Also evidence of
flow was documented in several locations along the channel.
At the February 2015 survey, a clear channel with flow was evident in the vicinity
of USC -11 B to USC -10B and persisted to USC -813. Also, at the February 2015 survey, as noted
in previous surveys, in the upper Scott Creek stream valley, downstream from USC -713, although
the valley slope flattens and the channel becomes more distributed and less confined, low flow
was evident across the entire valley all the way to the constructed stream crossing and beyond.
Additionally, throughout most of the upper Scott Creek valley, other evidences of flow were seen
such as scour, sorting, and distinct channels. The detailed stream survey, along with photos, is
contained in Appendix B.
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Until the planted trees and shrubs reach enough height to shade the valleys,
development of dense herbaceous vegetation will continue to occur in many areas. This
herbaceous layer can attenuate flow events and reduce velocity below the point of scour and can
also obscure recognition or prevent formation of other incipient channel formation features.
Therefore, flow is presumed to have occurred with enough frequency in some valleys to maintain
persistent flow paths over the years although flow was not always observed in these paths at the
monthly check (e.g., middle UT1, UT3, and UT7 valleys).
3.2.3 Hydroperiods. In 2014, the majority of all wells exhibited wetland
hydroperiods regardless of rainfall conditions and when abnormally high rainfall is excluded (June
19 -July 31) (Tables 3a, 3b, 4a, 4b, and Figures 6 and 7). Most wells had several wetland
hydroperiods throughout the year and various other days scattered throughout the growing
season where water levels were -12 inches or shallower. The reported hydroperiods at a few
locations were possibly shorter than what actually occurred due to well malfunctions. (The wells
are identified on Figures 6 and 7.) These gaps are shown on the monthly tables that depict 2014
daily noon well readings and rainfall included on the companion thumb drive to this report.
3.2.3.1 Riparian Headwater Systems/Bottomlands. During all rainfall
conditions in 2014, most (78 out of 94) of the wells considered "riparian" (located within a stream
or headwater valley) exhibited a wetland hydroperiod greater than 12.5 percent of the growing
season (Table 3a, Figure 6), nine more wells than 2013 (in 2013 the amount also increased from
the previous year). Two wells did not exhibit a wetland hydroperiod greater than 6 percent.
However, only one of those wells did not record a wetland hydroperiod at all and the other one (in
a soil mapped on the soil survey as upland) exhibited a wetland hydroperiod slightly above the
minimum 14 days. The shorter hydroperiods may be due to microtopography or that a well is
located slightly upslope of the riparian valley edge, or to drawdown by the adjacent stream
hydrology. Also, there might be small, non -hydric soil inclusions along valley axes.
When excluding the time period during above normal rainfall, only two
wells were categorized in the next drier hydrologic zone, but they still had wetland hydroperiods
(Table 4a, Figure 7). Some, but not most, of the other wells had reduced wetland hydroperiods,
but not enough to be categorized in a drier zone. All but one of the riparian wells also measured
water tables shallower than -12 inches continuously between 1 February and 27 February (Table
3a).
3.2.3.2 Non -riparian Hardwood Flat. During all rainfall conditions in
2014, only one of the 110 wells located in non -riparian areas out of the valleys did not exhibit a
wetland hydroperiod (two less than last year) and most wells exhibited a wetland hydroperiod
greater than 12.5 percent of the growing season (103 wells, many more than in 2013) (Table 3b,
Figure 6). Five of the 103 wells recorded a continuous wetland hydroperiod for the entire growing
season. The short wetland hydroperiods or lack of a wetland hydroperiod might be due to
microtopography. When excluding the time period with above normal rainfall, only the five wells
with the continuous wetland hydroperiod for the entire growing season were categorized in the
next drier hydrologic zone (Table 4b, Figure 7). Most other wells were already below wetland
water level depths during that time period. All wells also measured water tables shallower than -
12 inches continuously from 1 February through 27 February.
In the wetland enhancement area (the wetland "tongue" upslope of upper
Scott Creek), where pre -construction data exists for two wells (HS16 and HS17), those wells
have recorded longer hydroperiods post -construction.
3.2.4 Hydroperiod Comparison to Control Forests.
3.2.4.1 Plum's Pit. All four wells were drier in 2013 than in 2012, but
they were slightly wetter in 2014 than in 2013. Similar to the hydroperiods of wells at Hell
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Swamp, the longest wetland hydroperiod at each Plum's Pit well occurred before the period of
above normal rainfall (Tables 3b, 4b, and Figures 6 and 7). All of the wells recorded wetland
water tables many more days other than the consecutive days of their hydroperiods (Tables 3b
and 4b). Three wells also measured water tables shallower than -12 inches from 1 February
through 27 February and the fourth well recorded those levels for 22 days in that period (Table 3b
and 4b). These wells recorded similar hydrologic patterns as other wells in similar topographic
positions at Hell Swamp.
3.2.4.2 Windley Tract. The 2014 wetland hydroperiods were similar to
2013 hydroperiods. Two of the wells only had a wetland hydroperiod before the above normal
rainfall but the third well also had a short wetland hydroperiod after the above normal rainfall time
period (Tables 3b and 4b). All of the wells recorded wetland water tables many more days other
than the consecutive days of their hydroperiods (Tables 3b and 4b). Two of the wells also
measured water tables shallower than -12 inches from 1 February through 27 February while the
third one measured those depths for 26 days (Table 3b). These wells recorded similar hydrologic
patterns as other wells in similar topographic positions at Hell Swamp.
3.2.4.3 Winfield Tract. In 2014, during all rainfall conditions, only one of
the seven wells did not exhibit a wetland hydroperiod (Table 3b, Figure 6) and it has not had a
wetland hydroperiod since monitoring began. All wells recorded water tables shallower than -12
inches at other times than the longest hydroperiod and four wells recorded those levels for most
or all of February (Tables 3b and 4b). The longest wetland hydroperiods occurred before the time
period of above average rainfall (Table 4b.) These wells recorded similar hydrologic patterns as
other wells in similar topographic positions at Hell Swamp.
3.3 Vegetation. The yearly treatment to control the invasive common reed
(Phragmites australis) occurred 11 and 12 August 2014 using a combination of Glyphosate and
Imazapyr. Treatments were applied in the lower, unplanted swampy area of Scott Creek, the
lower end of the UT6 and UT7 valley, the lower end of UT5, and along the filled former
agricultural channel, for a combined total of approximately 16.5 acres. This was the fifth year of
treatment and as the density of the reed was less than previous years, the applicator determined
that a second treatment in 2014 was not necessary. An additional small area (approximately 20ft
by 20ft) along the perimeter road in the southeast edge of the property was also treated in
August. The reed appears diminished and occurs in only spotty patches in the areas that have
been treated.
The Corps determined that three tree species can outcompete young planted trees at a
mitigation site due to their quick growth and need to be monitored as nuisance species to ensure
they do not take over a mitigation site. The three species are loblolly pine (Pinus taeda), red
maple (Acer rubrum), and sweetgum (Liquidambar styracif/ua). Results of the first nuisance
monitoring survey, which occurred in the second year (2011) of site monitoring, indicated that
when all three species were combined, they represented 47.8 percent of the 180 stems counted
in the 123 nuisance plots. The amount of loblolly pine was identified as a potential problem in
three plots. For more information see the second annual (2011) report (CZR 2012). Results of
the second nuisance monitoring survey, which occurred in the third year (2012) of site monitoring,
indicated that when all three species were combined, they represented 40 percent of the 370
stems counted in the 123 nuisance plots. The 2012 monitoring showed that other species not
considered nuisance trees were establishing themselves, reducing the percentage of the
nuisance trees. Furthermore, in 2012, six plots contained 78 percent of the nuisance stems.
Results of the third nuisance monitoring survey, conducted in 2013, were similar to those in 2012.
Nuisance stems comprised 38.5 percent of all stems in the nuisance plots in 2013. The average
heights of red maple and sweet gum were less than the average height of the planted stems and
the average height of pine was the same as the planted stems. When all three species were
combined, the average height was less than the average height of the planted stems. Again, the
majority of nuisance stems (70.1 percent) were in six plots, although one of the plots from 2012
was not listed in the top six in 2013 and one plot that was not listed in 2012 was listed in 2013 in
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the top percent. Five of the six plots in 2013 contained 67.2 percent of the pine stems, one plot
contained 92.3 percent of the maple stems, and one plot contained 66.0 percent of the sweet
gum stems. (Only one of the six contained more than one nuisance species.) The rest of the
nuisance stems were scattered across the plots. The six plots are all on the edges of Hell
Swamp adjacent to existing pine stands or mixed forest, where invasions of nuisance species are
more likely to occur.
In November of 2013, a site visit and aerial photos were used to identify 25 polygons with
a higher density of pine trees than other areas. In February 2014, 20 of those polygons
(approximately 18.2 acres) were selected and flagged for pine removal (Figure 8). The flagged
polygons did not delineate all pines in an area, but did contain the densest concentrations of
pines that were taller than 3 feet, a height threshold thought most competitive with the planted
trees. Slade Landscaping cut down all pines in the 20 polygons which were >3 feet tall in March
2014.
By use of only the number of planted stems that were unquestionably alive in the 142
monitoring plots, the most conservative estimate of survival is presented. Many stems may
appear dead or questionable, but based on prior monitoring experience, a stem needs to appear
dead (or not be found) for two sampling events before it is counted as dead. Tables 5 through 10
document current survival of all vegetation plots and buffer plots compared to baseline and are
described in more detail in the sections below.
In summary, in 2014 the density of all planted trees was 350 unquestionably alive stems
per acre; the density of all unquestionably alive planted shrubs was 12 stems per acre; and the
density of all trees, shrubs, and unknown planted stems that were unquestionably alive was 362
stems per acre (Table 5). Excluding the unknowns, volunteer woody wetland non -nuisance
stems increase the tree density per acre by 96 to 447 and the volunteer woody wetland shrub
stems increase the shrub density per acre by 491 to 503 (Table 10). The vegetation information is
discussed by each category in the sections below. Appendix C contains the number of stems that
were alive in each plot for the baseline sampling event and for the fall 2014 survey.
3.3.1 Tar Pamlico Riparian Buffer Areas. The 19 original 0.017 -acre buffer
plots were established within what was then considered the riparian buffer footprint (0-50 feet
either side perpendicular from the centerline of the stream edge or headwater valley center). The
new consolidated Tar -Pamlico riparian buffer rule allows a wider footprint for potential buffer
credit of up to 200 feet each side.
In previous Hell Swamp annual monitoring reports, the data from the vegetation
plots anchored at the 14 wells considered riparian (those wells located within the 100 -foot wide
Valley 2 planting zone) were calculated as riparian stem data. However, in preparation of this final
report, it was noticed that the plots associated with five of those 14 wells are actually oriented
outside the 100 -foot valley. Additionally, for this final report PCS elected to propose for buffer
credit only the 0-100 feet of available Tar Pamlico riparian buffer on each side and to end the
restored upper Scott Creek stream valley at stream array 11 (USC -11). As a result, 1) one plot
from UT8 valley (HS -116) and one plot from UT4 valley (HS -92) were eliminated as potential
buffer plots as they are located almost entirely in the 100 -200 -foot buffer area of the stream/valley
and 2) the two vegetation plots within the upper Scott Creek valley upstream of USC -11 are also
eliminated (HS -17 and HS -18). For this report, to reflect status of buffer stems beyond 50 feet,
data from 14 of the 123 0.22 -acre monitoring plots that fell within 0-100 feet of the buffer zone
were added to the 19 original buffer plot data (a total of 33 buffer plots at 3.4 acres).
Coincidentally, while the number of plots representative of the riparian area is still 14, as in
previous reports, some plots were not included in riparian vegetation data in those previous
reports.
Overall survival of planted trees that were unquestionably alive in the 19 0.017 -
acre riparian buffer plots from baseline (mid -summer 2010) to fall 2014 was 74 percent, with a
corresponding density of 628 trees per acre (Table 6), slightly less stems than last year. Sweet
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bay (Magnolia virginiana), red bay (Persea palustris), water tupelo (Nyssa aquatica), sweet
pepperbush (Clethra alnifolia), and titi (Cyrilla racemiflora) had the lowest survivals (47, 14, 40,
38, 40 percent, respectively) (Table 6). Nine of the 19 planted tree species had 80 percent or
greater survival, with seven of the nine at 100 percent (Table 6). Only two shrub species
(Leucothoe [genus changed to Eubotrys] racemosa and Virginia willow [Itea virginica])
represented by only a few stems were found in the original 19 riparian buffer plots, which is likely
due to the overall low density of shrubs across the site and the small size of the buffer plot.
Overall survival of shrubs in these 19 plots from baseline (mid -summer 2010) measurement to fall
2014 was 67 percent for stems that were unquestionably alive with a corresponding density of 25
planted shrubs per acre (Table 6), the same as last year.
Within the 14 0.22 -acre plots located within the 0-100 foot Tar Pamlico riparian
buffer zone, overall survival of planted trees from baseline (mid -summer 2010) to fall 2014 was
80 percent for stems unquestionably alive, with a corresponding density of 348 stems per acre
(Table 7). Out of the confidently identified tree species, red bay and sweet bay had the lowest
survival in 2014 (12 and 27 percent, respectively). Survival of American holly (Ilex opaca) was
not that much higher at 38 percent. Survival of eight of the 17 planted tree species was 90
percent or greater and four of these eight were 100 percent. Overall survival of shrubs from
baseline (mid -summer 2010) to fall 2014 was 65 percent for stems that were unquestionably
alive, with a corresponding density of 10 shrubs per acre in these 14 plots (Table 7). Virginia
willow (Itea virginica) was the most common shrub in the plots.
Density for all planted tree and shrub species unquestionably alive after the fall
2014 survey in the smaller buffer plots was 653 stems per acre (Table 6) and in the larger plots it
was 472 stems per acre (Table 7). When data from all plots within the 0-100 foot buffer zone are
combined, density for all planted tree and shrub species unquestionably alive is 517 (1,759 alive
stems/3.4 acres) (Tables 6 and 7).The current densities are much higher than the 260 stems
required for success (wetland or buffer restoration criteria). The smaller plots contain nine tree
species with survival of 80 percent or greater, which results in a diverse habitat, especially with
the five other planted tree species represented in the zone with a survival of 50-79 percent.
Survival for seven of the 19 tree species planted is 100 percent. In the 14 larger riparian plots,
eight tree species had a >_90 percent survival, with three more not far behind, which also
contributes to a diverse habitat. No single species is represented by more than 50 percent in any
of the 33 riparian buffer plots.
3.3.2 All Vegetation Plots. Previous monitoring reports for this site have split
the vegetation data from the 123 plots into riparian and non -riparian categories based on the
assumption that each plot anchored at a "riparian" well represented conditions in a stream valley.
As stated in Section 3.3.1 above, some plots were erroneously included in the riparian category in
these reports. For this final report all stem data from all 123 0.22 -acre plots have been presented
in various combinations without reference to hydrological status or geomorphic location in order
for the site vegetation to be evaluated in its entirety (Tables 7, 8, and 9). (As stated above, data
from the 19 small buffer plots and the 14 other plots considered riparian (the 14 0.22 -acre plots
located within the 0 -100 -foot valley) were used alone to calculate stem density in the Tar -Pamlico
riparian buffer area).
Overall survival of planted trees unquestionably alive in the 109 0.22 -acre plots
not used in the buffer from baseline (mid -summer 2010) to fall 2014 was 83 percent, with a
corresponding density of 343 trees per acre (Table 8). Out of the 24 confidently identified tree
species, five species had low survivals ranging from 13 to 55 percent and eight species had 90
percent or greater survival, one of which was 100 percent-possumhaw (Ilex decidua) (Table 8).
Overall survival of planted shrubs from baseline (mid -summer 2010) to fall 2014
was 78 percent for stems that were unquestionably alive, with a corresponding density of 12
shrubs per acre (Table 8). Swamp rose (Rosa palustris) had the lowest survival (0 percent), but
was represented by only one stem, and was followed by spicebush (Lindera benzoin, 20 percent)
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and possumhaw viburnum (Viburnum nudum, 33 percent) (Table 8). Swamp doghobble
(represented by one stem) had the highest survival (100 percent) and five other species had
greater than 80 percent survival.
Density in the 109 plots for all planted trees and shrubs combined after the 2014
survey was 355 stems per acre for all species unquestionably alive (Table 8), which is higher
than the required 260 stems. The site is diverse with 14 tree species and six shrub species with
a greater than 80 percent survival. A total of 35 planted tree and shrub species are
unquestionably alive.
When all 123 0.22 -acre plots are combined, survival of planted trees and shrubs
unquestionably alive is 80 percent with a density of 359 stems per acre by the fall of 2014 with 20
of the 35 species planted at a survival of >_80 percent (Table 9).
3.3.4 Volunteer Woody Vegetation. Volunteer woody stems 12 inches or taller were
counted by species and tallied separately from the planted stems in the plot. Upland species and
nuisance species (sweet gum, red maple, and loblolly pine) were not counted towards stem
density for wetland restoration success. However, the 2014 consolidated buffer rules allows
inclusion of all volunteer woody stems regardless of wetland or nuisance status. Table 10 shows
the tally of the volunteer and woody planted stems in the 142 vegetation plots and results are
described in more detail below in the two categories (buffer plots and non -buffer plots).
3.3.4.1 Tar -Pamlico Riparian Buffer. In the 14 riparian 0.22 -acre and the 19
0.017 -acre plots, woody volunteer stem density was 326 trees per acre (large and small species)
and 850 shrubs per acre for a total of 1,176 stems per acre (Table 10). In the plots, 13 tree
species were represented by approximately 1,110 stems (Table 10). The most numerous
species were wax myrtle and loblolly pine. Sixteen stems of buttonbush (wetland shrub) were
documented but the rest of the shrub stems were of groundsel tree.
3.3.4.2 All Vegetation Plots. Four small and 14 large wetland non -nuisance
tree species were represented by approximately 2,594 stems in the 123 0.22 -acre plots (Table
10). Total volunteer tree stems of all species was 9,935. The most numerous volunteer tree
species were wax myrtle and loblolly pine. Fifteen of the tree species and approximately 25
percent of the stems have a wetland status and are not considered nuisance species. Five shrub
species were represented by approximately 13,286 stems, all were wetland species, and none
were nuisance species (Table 10). Volunteer woody wetland stem density was 587 per acre
(Table 10).
When the volunteer woody wetland tree stems are added to the planted tree
unquestionably alive stems, density of trees in the 142 plots totals 476 trees per acre (Table 5).
When the volunteer woody wetland shrub stems to the planted shrub stems unquestionably alive
density of shrubs totals 510 shrubs per acre (Table 5). When volunteer and planted trees and
stems are combined across the 142 plots wetland stem density is 986 per acre (Table 5).
3.4 Photographic Documentation. A few photos representative of 2014 conditions
are paired with baseline photos at the same location for comparison (Appendix D). More are
available upon request.
4.0 MONITORING SUMMARY
For reference, Figure 9 depicts the jurisdictional features on the Hell Swamp site prior to
restoration activities. This figure was included in the mitigation plan for the site submitted with the
CAMA major permit (shown as Figure 6 in Appendix D of the CAMA permit).
4.1 Hydrology. Post -restoration wetland vegetation monitoring began in 2010, but
hydrology and flow monitoring for success officially began January 2011. However, most wells
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outside the valleys were installed by March 2010. According to WETS rainfall estimates, 30 -day
rolling total rainfall amounts for 2014 were within normal range for most of the year, with only a
few periods of below normal and above normal rainfall (Figure 5). One of the periods of above
normal rainfall (June 19 -July 31) was high enough for a long enough time to cause the exclusion
of wetland hydroperiods during that time period. According to the US Drought Monitor, the last
four weeks of the growing season were classified as abnormally dry drought conditions. In 2014,
all but two wells on the entire Hell Swamp site, including those in the nine headwater valley
systems, recorded wetland hydroperiods during periods of normal or below normal rainfall.
Total annual rainfall collected at the on-site rain gauge over the over the five years of
monitoring is compared to the WETS Aurora data (+/- 30 percentiles and average for the period)
in Figure 10. Over the five years of monitoring (includes 2010), 94.6 percent of non -riparian wells
and 92.4 percent of riparian wells had a wetland hydroperiod for three or more years (data
collected during abnormally high rainfall was excluded when applicable) (Tables 11a and 11b
depict hydroperiods during all rainfall conditions and Tables 12a and 12b depict hydroperiods
during normal or below rainfall). As shown on Table 12a and Table 12b, during the monitoring
years nine wells did not meet the hydrology success criterion. Three of these wells (11, 94 and
120) experienced no wetland hydroperiods and the other six (43, 51, 66, 79, 91, and 122) had
wetland hydroperiods but did not meet the hydrology success criterion between 2010-2014
monitoring years. Wells at Plum's Pit, Windley and Winfield control forests recorded wetland
hydroperiods comparable to hydroperiods of similarly located Hell Swamp wells. Over the five
years of monitoring at the Windley control forest, all three wells have had a wetland hydroperiod
for all years and at Plum's Pit, three of the four wells had a wetland hydroperiod all years, while
one had a wetland hydroperiod for four of the five years (Table 12b). The Winfield wells have
only been installed for three full growing seasons and when only those years are considered, five
of the seven wells had a wetland hydroperiod all three years, while one had a wetland
hydroperiod two of three years, and one has not had a wetland hydroperiod (Table 12b).
4.2 Wells with Wetland Hydrology underlain by Non -Hydric Soil on Soil Survey. A total of
26 well locations at Hell Swamp are shown in the Beaufort County Soil Survey as underlain by
either Dragston or Augusta soil map units, both non -hydric soils (Figure 11). Analysis of the soil
descriptions taken during original well installation and the wetland hydroperiods during normal
rainfall or below over the monitoring years (including early 2015) indicate 23 of these locations
have met the hydrology restoration criterion. The soils at these 23 locations were likely hydric at
the time of well installation (the top 12 inches of soil with chroma of 1 or 2) and have either
become more hydric since, or have changed in response to increased periods of saturation. Of
these 23 locations, many are near a mapped boundary between a hydric and non -hydric soil map
unit (either Augusta/Tomotley, Dragston/Portsmouth, or Drag ston/Ara pahoe) (Figure 11).
To document the analysis for the wells that met hydrology success criterion but are
shown as within a mapped non -hydric soil unit, post -restoration soil profiles were described using
a Dutch auger and 2000 Munsell Soil Color Chart (Revised Washable Edition), national hydric soil
indicators noted per the Field Indicators of Hydric Soils in the United States (USDA 2010), and
photographs of the profiles taken at 17 of the 23 locations in late 2015/early 2016. While use of
the USDA 2010 national field indicators was not common practice at the time of monitoring well
installation, the document states that the indicators are most useful at the upland/wetland
boundary during delineations and that interior soils of wetlands often lack any of these indicators.
Table 13 repeats the hydroperiods and drought status information for each of these 23 wells from
Table 12a or 12b, shows the well installation soil profile descriptions for each of the 23, and the
post -restoration profile descriptions for the 17 locations revisited. For the six locations that were
not revisited, a hydric soil indicator was assigned based on the soil profile at installation and
changes noted in many of the 17 new profiles (e.g., lower chromas since installation, low-chroma
horizons thickened, and/or other evidence of increased saturation and its concomitant effects on
iron reduction/depletion); assigned indicators are shown in italics in Table 13. Soils at 22
locations contained at least one national hydric soil indicator and soil at the one location which
lacked a national indicator (well 65) shows a response to post -restoration increase in saturated
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conditions. The recent soil profile photographs of the 17 locations are included as Appendix E
only on the thumb drive which accompanies this report.
Of the nine wells which failed to meet the hydrology restoration success criterion between years
2010-2014 (wells 11, 43, 51, 66, 79, 91, 94, 120, and 122), five were among the 26 wells shown
within a mapped non -hydric soil unit (wells 11, 66, 79, 91, and 122). Well data collected in 2015
for the nine wells which did not meet the hydrology success criterion were analyzed for wetland
hydroperiods which occurred prior to cessation of monitoring. Five of the nine wells (43, 51, 66,
91, and 122) experienced a 2015 wetland hydroperiod during normal or below rainfall; the
hydroperiods ranged from 12.4 percent to 19.5 percent (28 February — 4 April and 28 February —
24 April). When the 2015 hydroperiods are added to the 2010 — 2014 data shown in Table 12b,
five of the nine wells failed to meet the >50 percent criterion (wells 79 and 122 had only two years
with wetland hydroperiods: wells 11, 94, and 20 had none).
4.3 Stream Flow and Consolidated Tar -Pamlico Buffers. As in previous monitoring years,
evidence of flow (e.g., braided patterns, channel formation, flowing water, sediment sorting,
vegetation oriented parallel to flow direction, lack of vegetation in persistent flow path, bed and
bank) continued to be seen in many areas of most of the headwater stream valley systems, as
well as the single -thread channel of Scott Creek. By April 2015, out of the 40 locations in the
stream valleys that were visited monthly, 30 met minimum restoration success criteria for flow
and all streams or headwater valleys qualify for buffer mitigation. Figure 12A (aerial photo base)
and 12B (non -aerial base) depict streams/valleys and Tar -Pamlico riparian buffers calculated
based on stem data and documented flow observed during annual stream surveys, well checks,
or recorded by the low flow gauges before their removal. Upper Scott Creek and the majority of
the headwater streams met the zero to first order, or first or second order stream restoration
criteria; however, in a few locations within some valleys, flow was observed more than once
during normal rainfall or below, but was not documented with a frequency to meet the zero to first
order stream restoration criteria (yellow dots on Figure 12A/B). However, in some instances (e.g.,
in UT3, UT6, and UT8), observed flow upstream from the lower flow frequency locations met the
success criteria. In these situations, water in the entire valley was presumed to flow downslope
and therefore, the buffers are depicted as restored. For other low frequency locations (e.g.,
topmost flow observation location in USC, upper portions of UT1, UT2, and UT7 and all of UT4,
flow was either inferred to have occurred based on conditions during previously observed events
(see next paragraph), or the channel was considered ephemeral under 15A NCAC 02B.0295 (m)
(2) (G) of the October 2014 temporary consolidated buffer rule. Buffer restoration at these other
low frequency locations are depicted as Inferred flow/ephemeral buffer restoration on Figure
12A/B.
The appendix table of observed flow from each annual report was used to build the
summary of events shown in Table 14. The effect of flow attenuation from herbaceous
colonization in some valleys is evident over time in this table, as the number of easily observed
flow events often decreased over time (Table 14; number on left side of "P'). To analyze the
evolution of these systems, these appendix tables were studied as a group for this summary. It
was evident that when herbaceous vegetation was absent or nascent (first two years), low flow
was more confidently, and/or frequently noted, and sometimes at rather shallow depths. It was
also noted that in later years, sometimes at greater depths, the observer was unable to discern
flow. Therefore, because valley slope did not change and base flow or storm water flow in
ephemeral channels continues downslope, it is logical to conclude that at depths greater than
when low flow was originally and easily noted, flow is inferred to have occurred although
obscured and/or attenuated by vegetation. These inferred flow events in the headwater valleys
are added to the observed events and the total is shown on the right side of the "P' in Table 14.
This analysis increases the number of locations that meet the minimum restoration success flow
criteria to 38. The remaining two locations had several observed or inferred flow events but did
not meet the minimum flow criteria (UT43-4B and UT4-1 B). For USC -313 and USC -413, in the
constructed single thread channel, the flow success criterion is per 2003 Stream Mitigation
Guidelines (two bankfull events in separate years) as opposed to the headwater valley
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requirement. For these two locations, both criteria are shown in Table 14. Appendix B of this
report contains tables of information about 2014-2015 rainfall prior to monthly observations of
flow, 2014-2015 flow observations, and list of 2014-2015 selected flow videos; the appendix also
contains all flow videos and selected photos from 2010-2013. (Flow videos are found only on the
thumb drive which accompanies this report.)
Restoration design for the entire UT6 headwater stream valley was for a narrower, more
constricted valley flow way than existing conditions; however, at the time of restoration activities
at Hell Swamp in 2009/2010, wetness in the existing wetland in the most downstream portion of
the UT6 valley prevented any construction. With no construction, the two stream well arrays and
low flow gauges originally planned for monitoring what was anticipated to be the narrow stream
valley in the most downstream portion of UT6 were never installed (UT6-1 and UT6-2) and no
buffer plots were established to monitor vegetation at or below the UT6-3 well array. No
construction resulted in a wider, wetter, swampier stream valley in this portion of UT6 with longer
periods of ponded water or low flow and densely colonizing herbaceous vegetation than originally
planned. When the restored flow from UT7 and upper UT6 reaches the lower UT6 valley, it loses
velocity and spreads out across the wider unconstructed flow way. Lower more diffuse flow has
been difficult to observe or discern in the swampy vegetation and deeper water depths but is
inferred to continue throughout the lower UT6 valley. At the very bottom of UT6, flow becomes
constricted again and has formed a narrow, permanent channel just upstream of its connection
with Scott Creek (repeatedly documented in annual stream surveys).
Under these conditions, the outside edge of the wider headwater valley/flow way became
the inside edge of the woody riparian buffer along the unconstructed portion of the UT6 stream
valley. As there were no small buffer plots in lower UT6 and only one planted stem monitoring
plot within the UT6 valley (plot 82), to further document buffer restoration CZR biologists
photographed conditions in the unconstructed lower valley on 16 December 2015 and collected
stem data in the riparian buffer (0-100 feet) beyond the valley/flow way edge.
Four rectangular 0.06 -acre plots (two plots each side in the lower UT6 valley) were
marked and all planted and volunteer woody stems within the rectangle counted. The outer edge
of the valley/flow way (and inside edge of the plot) was determined to be at either a visible
topographic change and/or a change in vegetation (e.g., a combination of either less, or no,
Juncus and Typha and more woody stems). The plots were 25 x 100 feet with the narrow edge
parallel to valley axis at the outer edge of the valley/flow way and the long edge perpendicular.
Plots A and B were along the east side of lower UT6 and plots C and D were along the west side.
The two most upstream plots (B and C) were located about halfway to the UT6-3 monitoring
array. A figure showing the locations of the four UT6 plots and representative photographs with
explanatory captions to show conditions within the unconstructed lower UT6 valley on 16
December 2015 are included in Appendix C.
To meet the riparian buffer 260 stem/acre success density, at least 16 woody stems were
needed within each of the four buffer plots A - D, a minimum clearly exceeded (Table 15). A total
of 15 species were counted in the plots and the dominants were groundsel tree, loblolly pine, and
wax myrtle. While the four plots are dominated by volunteer woody species, the two upstream
plots contained more diversity and more planted stems, a trend which was apparent as the valley
edge was walked on 16 December. The biologists crossed UT6 at the UT6-3 array to access the
west side, and as they walked the entire valley edges below UT6-3, it was apparent that many
more planted stems were easily visible within the 0-100 foot buffer in the area of the valley
upstream of plots B and C. Based on the increasing numbers of planted stems, year 5 planted
stem density in tree plot 82 (-324/acre; the only vegetation plot in the vicinity of the UT6 valley),
and the data collected in buffer plots A and B, it was determined that additional buffer plots were
not needed above the UT6-3 array or between the UT6-3 array and plots B and C. Of general
interest, during the December visit, it was noted that within the 100 -foot buffer on the west side of
lower UT6, the first 25 or 30 feet appeared to be dominated by herbaceous species compared to
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Fifth Annual and Summary Report February 2016

the east side where woody shrubs were consistently present within the first several feet of the
buffer.
Therefore, with a combination of observed or inferred flow, and/or ephemeral
characteristics, in conjunction with stem counts, all streams or headwater valleys demonstrate
flow and that Tar -Pamlico riparian buffers have been either restored or preserved. As previously
noted, for the Hell Swamp mitigation site, only the first 100 feet of the available buffer mitigation is
proposed as shown on Figure 12A/B.
4.4 Vegetation. Overall survival of unquestionably alive trees in the 109 non -riparian
hardwood flat plots from baseline (mid -summer 2010) survey to fall 2014 was 83 percent, with a
corresponding density of 343 trees per acre and overall survival of shrubs was 78 percent, with a
corresponding density of 12 shrubs per acre. Survival and density in the non -riparian hardwood
flat areas for all trees and shrubs combined after the 2014 survey was 80 percent and 355 stems
per acre for all species unquestionably alive. Only three tree species are each more than 10
percent of the total and they compose 40 percent of the tree stems. When all 123 of the larger
plots are combined, survival and density of planted trees is 83 percent and 347 stems per acre
with shrub survival at 77 percent and 10 stems per acre. After adding the volunteer woody
wetland stems to the planted stems in the 123 plots, density of trees and shrubs combined is 944
stems per acre.
Overall survival of planted trees unquestionably alive in the small riparian plots from
baseline (mid -summer 2010) to fall 2014 was 74 percent, with a corresponding density of 628
trees per acre and overall survival of shrubs was 67 percent, with a corresponding density of 25
shrubs per acre. No one tree species dominates the area; five tree species are each more than
10 percent of the total stems and together compose 66.7 percent of the tree stems. Overall
survival of planted trees unquestionably alive in the large riparian plots from baseline (mid-
summer 2010) to fall 2014 was 80 percent, with a corresponding density of 348 trees per acre
and overall survival of shrubs was 65 percent, with a corresponding density of 10 shrubs per
acre. No one tree species dominates in these riparian plots either; four tree species are each
more than 10 percent of the total stems and together compose 62.1 percent of the tree stems. In
both the large and the small buffer plots, Virginia willow was the dominant shrub species.
Density in all 33 riparian buffer plots for all planted species unquestionably alive after the
2014 survey was 375 trees per acre and 12 shrubs per acre. After adding the volunteer woody
wetland stems to the planted stems, density in the riparian areas totaled 701 trees per acre and
861 shrubs per acre.
All planted areas are currently above density success requirements and survival of
several species of trees is high, equating to a diverse suite of habitats across the site. With the
high success rate of the planted trees after five years of monitoring and the not -too -wet, not -too -
dry conditions across the site (documented for four full years at all wells, five years at most non -
riparian wells), the Hell Swamp Mitigation Site has been restored to a functional coastal plain
headwater stream and wetland complex. Stream flow has been observed in most tributaries
during most years. Many mammals, amphibians, reptiles, and birds have been observed at the
site, including black bears, rabbits and other rodents, various waterfowl, bobwhite quail, American
bittern, short -eared owl, rough legged hawk, and bald eagles.
5.0 SITE CLOSE OUT SUMMARY
The USACE visited the site 29 January 2007 to confirm Section 404 jurisdictional areas around
Scott Creek. After that visit PCS added additional tracts of land which had more wetland areas
near Scott Creek and a small section near Smith Creek. Those areas were delineated by CZR
and confirmed by USACE, except for a few areas, on 8 May 2008. Additional waters of the US
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Fifth Annual and Summary Report February 2016

were also identified at that time. The additional wetland boundaries were adjusted according to
USACE direction and upper limits of waters of the US were flagged. The adjustments were
confirmed by USACE on 21 May 2008 and the Windley tract was evaluated. The jurisdictional
determination for the entire site was signed by the USACE on 29 July 2008 (Action ID SAW -
2008 -02014). The NC Division of Water Quality (now Division of Water Resources [NCDWR])
also visited the site in 2007/2008, agreed with the USACE jurisdictional wetlands/waters, and also
claimed an additional 2,382 linear feet of jurisdictional stream (ditched portion of upper Scott
Creek) (Figure 9).
As agreed by USACE and NCDWR representatives on 28 May 2015, monitoring at Hell Swamp
could cease and a final field visit for close out would occur in late 2015 or early 2016. Based on
the observations and data presented in previous monitoring reports and this summary report, the
Hell Swamp/Scott Creek mitigation site has met the performance criteria for the vegetative
(planted, volunteer, and nuisance stems) and hydrologic (wetland and flow) components as
specified in Table 1.
In preparation for the final field visit, an estimated mitigation yield for the site is shown in Figure
12A/B (Tar -Pamlico riparian buffers) and Figure 13 (wetland, stream, and coastal plain headwater
valley in addition to riparian buffers). Monitoring data indicate that the project has successfully
provided 1,025.93 acres of wetland restoration (agricultural fields and 2.69 acres along eastern
edge of Windley tract), 67.01 acres of wetland enhancement (existing wetland swamp forest of
lower Scott Creek and wetlands at the very top of upper Scott Creek referred to as the "tongue"
and along the northern edge of site), 25.31 acres of wetland preservation (the non-riverine wet
hardwood forest in the Windley tract), 4,655 linear feet of stream restoration of upper Scott Creek,
12,882 linear feet of coastal plain headwater stream restoration (UT1 — UT8), 6,015 linear feet of
stream enhancement (lower Scott Creek), 166 linear feet of stream preservation (Smith Creek),
90.68 acres of Tar -Pamlico riparian buffer restoration (0-100 feet either side), and 1.5 acres of
Tar -Pamlico riparian buffer preservation (lower Scott Creek and UT 8 downstream of Pungo
Creek Road) under the October 2014 Tar -Pamlico consolidated buffer rules (i) and (m); no buffer
acres are counted in the wetland acres Figures 12 and 13).
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LITERATURE CITED
CZR Incorporated. 2009. Compensatory Mitigation Plan for Restoration of Hell Swamp/Scott
Creek Watershed.
CZR Incorporated. 2010. As -Built Report for the Hell Swamp/Scott Creek Restoration Site.
CZR Incorporated 2011. Baseline and First Annual Report for the Hell Swamp/Scott Creek
Restoration Site.
CZR Incorporated 2012. Second Annual (2011) Report for the Hell Swamp/Scott Creek
Restoration Site.
CZR Incorporated 2013. Third Annual (2012) Report for the Hell Swamp/Scott Creek Restoration
Site.
Kirby, Robert M. 1995. The soil survey of Beaufort County, North Carolina. Natural Resources
Conservation Service, USDA.
U.S. Army Corps of Engineers. 2002. Regulatory guidance letter (RGL) 02-02. Guidance on
Compensatory mitigation projects for aquatic resource impacts under the Corps
regulatory program pursuant to Section 404 of the Clean Water Act and Section 10 of the
Rivers and Harbors Act.
U.S. Army Corps of Engineers, EPA, NC Wildlife Resources Commission, and NC Division of
Water Quality. 2003. Stream Mitigation Guidelines. Wilmington, NC.
U.S. Army Corps of Engineers. 2005. Technical Standard for Water -Table Monitoring of Potential
Wetland Sites. WRAP Technical Notes Collection (ERDC TN -WRAP -05-2.) U.S. Army
Engineer Research and Development Center, Vicksburg, MS
U.S. Army Corps of Engineers and NC Division of Water Quality. 2007. Draft information on
stream restoration with emphasis on the coastal plain. 4 April supplement to USACOE,
et al. 2003.
U.S. Army Corps of Engineers. 2008. Regulatory Guidance Letter (RGL) 08-03. Minimum
monitoring requirements for compensatory mitigation projects involving the restoration,
establishment, and/or enhancement of aquatic resources.
U.S. Army Corps of Engineers. 2010. Regional supplement to the Corps of Engineers wetland
delineation manual: Atlantic and Gulf coastal plain region. Version 2.0. J.S. Wakeley,
R.W. Lichvar, and C.V. Noble, eds. ERCD/EL TR -08-30, Vicksburg, MS.
U.S. Department of Agriculture, Natural Resources Conservation Service. 2010. Field Indicators
of Hydric Soils in the United States, Version 7.0. L.M. Vasilas, G.W. Hurt, and C.V.
Noble (eds.). USDA, NRCS, in cooperation with the National Technical Committee for
Hydric Soils.
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