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HomeMy WebLinkAbout20001085 Ver 1_Mitigation Information_199710281 1 1 1 1 i 1 1 i GREATER SANDY RUN AREA WETLANDS MITIGATION DEVELOPMENT ENGINEERING STUDY 95-10 FINAL MITIGATION BANK PLAN Marine Corps Base, Camp Lejeune, North Carolina Naval Facilities Engineering Command DEWBERRY &'DAVIS in cooperation with TRIANGLE WETLAND CONSULTANTS, INC. October 28, 1997 _ GREATER SANDY RUN AREA WETLANDS MITIGATION DEVELOPMENT ENGINEERING STUDY 95-10 FINAL MITIGATION BANK PLAN Marine Corps Base, Camp Lejeune, North Carolina U Naval Facilities Engineering Command DEWBERRY &*DAVIS in cooperation with TRIANGLE WETLAND CONSULTANTS, INC. October 28, 1997 r_? 1 1 i 1 1 1 GSRA Wetlands Mitigation Development TABLE OF CONTENTS 1.0 INTRODUCTION 2.0 EXISTING CONDITIONS 2.1. INTRODUCTION 2.2 HYDROLOGIC REGIME 2.3 SOILS 2.4 VEGETATION 2.4.1 HGM Types 2.4.2 Plant Community Types 2.5 LOCATION OF HGM TYPES 3.0 MITIGATION BANK DEVELOPMENT 3.1 INTRODUCTION 3.2 HYDROLOGY 3.3 VEGETATION 3.4 SOILS 3.5 REMEDIATION MEASURES 3.5.1 Drainage Ditch Alteration 3.5.2 Planting Plan 3.6 MONITORING 3.6.1 Mitigation Implementation Sequence 3.6.2 Mitigation Implementation Record 3.6.3 Hydrology 3.6.4 Soils 3.6.5 Vegetation 3.6.6 Observation 3.6.7 Success Criteria 4.0 MANAGEMENT PROTOCOLS 4.1 CONTINGENCY PLANS 4.1.1 Herbivory 4.1.2 Fire 4.1.3 Noxious Vegetation 4.1.4 Drought/Storms 4.2 NATURAL RESOURCE MANAGEMENT 4.3 MITIGATION BANK INSTRUMENT 4.4 CREDITING/DEBITING/ACCOUNTING PROCEDURES 4.5 RESPONSIBLE SPONSOR 5.0 REFERENCES Mitigation Bank Plan TOC I 1 GSR,4 Wetlands Mitigation Development LIST OF FIGURES Figure 1 Vicinity Map Figure 2 Master Development Plan Figure 3 Figure 4 HGM Types within GSRA Proposed Pocosin and Burned Pine Plantation Mitigation Areas Figure 5 Proposed Bottomland Hardwood Mitigation Area Figure 6 Monitoring Well Locations in Proposed Mitigation and Surrounding Areas Figure 7 Pocosin Reference Well #2 Figure 8 Pocosin Reference Well #3 Figure 9 Pocosin Reference Well #12A Figure 10 April 1994 Photograph of Burned Pine Plantation Area Figure 11 Proposed Pocosin and Burned Pine Plantation Areas with NRCS Soils Delineations Figure 12 Proposed Bottomland Hardwood Area with NRCS Soils Delineations Figure 13 Proposed Pocosin and Burned Pine Plantation Mitigation Areas with Ditch Plug Locations Figure 13AWater Control Structures For Burned Pine Plantation Mitigation Area Figure 14 Proposed Bottomland Hardwood Mitigation Area with Timber Dam, Monitoring Well and Vegetation Plot Locations Figure 15 Timber Dam Detail Figure 16 Planting Plan for Burned Pine Plantation Mitigation Area Figure 17 Proposed Pocosin and Burned Pine Plantation Areas with Monitoring Well and Vegetation Plot Locations Figure 17AProposed Monitoring Well Locations in Sister Drain to Big Shakey Swamp Figure 18 Boundary of Big Shakey Swamp Figure 19 Boundary of the Pocosin and Burned Pine Plantation LIST OF TABLES Table 1. Summary of soil types within GSRA Table 2. Delineation of HGM and community types and subtypes at GSRA Table 3. Relative Species Mix for Burned Pine Plantation Mitigation Site SUPPORTING DOCUMENTS AVAILABLE UNDER SEPARATE COVER Phase I - HGM/Habitat Model Parameter Selection Report Phase II - HGM/Habitat Model Functional Analysis Mitigation Ratio Development Memorandum of Agreement Hydrologic Monitoring Reports ` Drainmod Study I Mitigation Bank Plan TOC 2 n 1 I GSRA Wetlands Mitigation Development 1.0 INTRODUCTION The Greater Sandy Run Area (GSRA) contains approximately 41,000 acres and is located to the southwest of the Marine Corps Base, Camp Lejeune (MCBCL) in Onslow County, North Carolina. - The property is bounded by U.S. Highway 17 to the east and southeast, State Road 50 to the southwest and west, and Padgett, Haws Run, Dawson Cabin, and High Hill Roads to the north (see Figure 1). This property was purchased in 1992 to alleviate deficiencies in training areas and available firing ranges at the MCBCL. The master plan for GSRA calls for ten training ranges and i ancillary support facilities (see Figure 2). Silvicultural activities dating back over four decades has left the majority of the GSRA ditched, drained and dominated by pine plantations at various stages of development. Due to the significant amount of degradation caused by prior land management practices, many of the areas once considered wetlands are now altered. In the GSRA, determining what qualifies as a jurisdictional wetland under the 1987 manual requires a fair amount of judgement. For instance, a ditched and drained pocosin system can still have the appropriate wetland vegetation and organic soil, but determining if the hydrologic indicators are present is where significant judgement is involved. This determination is key for judging if the area in question is a degraded but still viable wetland, or whether the hydrologic parameter for determining jurisdictional wetland status is absent. The MCBCL has worked diligently since January of 1994 to prepare and gain approval of a mitigation plan for the GSRA. During the course of the past two years, the MCBCL has worked side by side with the Corps of Engineers (COE) to collect the information necessary to decide the hydrologic regime of the potential Mitigation Banks. At great expense, the MCBCL placed 166 ground water monitoring wells throughout the Mitigation Banks based on a plan conceived and approved in conjunction with the COE Waterways Experiment Station (WES) in Vicksburg, Mississippi. In addition to the well placement, two methods currently under development by the COE were utilized for the wetland functional analysis, the Hydrogeomorphic Methodology (HGM) and Habitat Value Assessment (HVA). The HVA is based on the Wildlife Community Habitat Evaluation model. Field tours were conducted at critical stages in the development of the models to allow representatives from all interested regulatory agencies a chance to gain first hand knowledge of the plant communities and HGM types within the GRSA and participate in the selection of components to be included in the functional analysis. By working together, a mutual understanding of the existing GSRA ecosystem was reached along with mitigation efforts which may best serve the overall system. 11 1 Mitigation Bank Plan Page 1 1 1 1 1 1 r r i r i i GSRA Wetlands Mitigation Development J MOFFMANM J/ • , ?+ s I FOREST i • i ?. cgwm R. ? .......: -:::. CAMP \ EWE s ?rt 40 •. S AVOY BWI Al1EA ?? L : z".6 401 OHMS iswo w PON 0 1000 10000 21000 _-?. 4 Z : I 0 Figure 1 -- Vicinity Map Source: Greater Sandy Run Area Master Development Plan Multi Project Mitigation Area Plan Page 2 1 1 GSRA Wetlands Mitigation Development P-949 Multi-Purpose Training Range (MPI'R) SR-7 P-935B Multi-Purpose Machine Gun Range (MPMG) SR-3 OP- P-934B Multi-Purpose 3 Machine Gun Range P-935B Anti-Armour r (1VIPMG) SR-8 Tracking Range SR-4 -935 Anti-Amour P-1 king Range Tracking HIZ 1 V P-934A Multi-Purpose Gunnery Range ange SR-2 Gunnery Machine Gun Range (MPMG) SR-9 P-935A Infantry Squad Battle Course USBC) SR-1 P-934A Range Control & Range Maintenance P-935A Infantry Platoon OP-120 4 Buildings Battle Course (IPBC) Battalion Bivouac Area #I SR-6 Helicopter Drop Zone ' Ibrkey -8 OP ZZ Battalion Bivouac Area #2 P-933 Multi-Purpose Range Complex (MPTR) SR-10 jIRC.M ? 125' Observation lbwer ¦ Helicopter Landing Zone (MU O Battalion Bivouac Area 0.11 ¦ Strucare 5 - Access Road TacticaUPerimeter Road P-934A Mock Maintenance Tank Trail Building P-934A Mock Terminal D p ftopenY Line ` Clear Zone P-934A Mock ControlTower P-934A Mock Hangars OSurfhce Danger Zone 200' Microwave 'Rower Figure 2 -- Master Development Plan Source: Greater Sandy Run Area Master Development Plan ion Area Plan Mu ti Project MitigRt Page 3 GSRA Wetlands Mitigation Development 2.0 EXISTING CONDITIONS 1 2.1 INTRODUCTION Preliminary assessment of the GSRA was conducted during May 1995, during which more than 200 detailed sample plots were established. The sample plots were concentrated in areas with potential impacts due to new training facility construction and potential Mitigation Banks. The preliminary data included basal area of overstory species; coverage estimates of sapling, shrub, and herbaceous species; information regarding soil morphology; estimates of fire frequency/intensity; depth to water table; stand age; various wildlife habitat parameters; and distance to ditches. For a detailed account of all the information collected and analyzed, see the Phase I - HGM\HABITAT Model Parameter Selection report. The majority of GSRA was acquired from International Paper Company (36,500 acres). During the 1980's, International Paper Company intensively managed portions of the site for forest products and installed extensive ditch systems in the north pocosin, south pocosin, and wet mineral flats surrounding the pocosin areas. Many of the non-alluvial hardwood and alluvial hardwood forests were channelized prior to the 1980's, presumably to facilitate drainage and access to large diameter cypress (Taxodium distichum) in these stands. During the early 1990's, many pine stands were clear cut and abandoned. Presumably, this lack of site preparation and regeneration was due to the pending acquisition of GSRA by MCBCL. Today, many of these previously harvested pine stands have naturally regenerated to mixed pine-hardwood or hardwood stands. Although fire suppression has continued on GSRA, there have been several recent fires that have completely destroyed overstory pine trees. Specifically, pine plantations adjacent to the southern border of the south pocosin, in the central portion of P-949, and north of Moore's Ridge Road near U.S. Highway 17 have been altered by recent, intense fires. These burned areas are characterized by a dominant herbaceous/low shrub stratum with complete overstory mortality. 2.2 HYDROLOGIC REGIME Drainage from GSRA is mostly to the west, through Juniper Swamp Creek and Holly Shelter Swamp Creek. Great Sandy Run Pocosin is divided by a low sand ridge (Moore's Ridge Road) into the north pocosin and south pocosin. The north pocosin primarily drains into Holly Shelter Swamp Creek. However, the south pocosin drains into both Holly Shelter Swamp Creek and Juniper Swamp Creek. Much of the drainage on the eastern side of GSRA between the pocosin areas and U.S. Highway 17 flows into the pocosins. The impact area for P-949 drains into the north pocosin, and the impact area for P-933 flows into Juniper Swamp Creek. Other than the bottomland hardwood sites, the majority of GSRA is strongly influenced by seasonal precipitation and evapotranspiration. 1 I Mitigation Bank Plan Page 4 1 1 [l t t 1 L 1 L GSRA Wetlands Mitigation Development 2.3 SOILS GSRA is entirely within the Lower Coastal Plain Physiographic Province and is characterized by poorly drained, broad, interstream divides. Great Sandy Run Pocosin and White Oak Pocosin (Hoffman Forest) are examples of the thick organic deposits that have formed in some of these interstream divides within Onslow County. A variety of soil types occur within GSRA (Table 1). Foreston loamy fine sand is a non-hydric soil mapping unit, and Stallings loamy fine sand is a mapping unit with hydric inclusions. Both mapping units primarily support flatwoods plant community types. Croatan muck is a hydric mapping unit and primarily supports pocosin plant community types. Leon fine sand, Murville fine sand, and Torhunta fine sandy loam are hydric mapping units and primarily support flatwoods plant community types. Muckalee loam is a hydric mapping unit and supports both non-alluvial hardwood forest and alluvial forest types. Woodington loamy fine sand is a hydric mapping unit and supports both non-alluvial hardwood forest and flatwoods plant community types. Table 1. Summary of soil types within GSRA' Soil series Mapping Symbol Soil subgroup Croatan muck Ct Terric Medisaprists Foreston loamy fine sand FoA Aquic Paleudults Leon fine sand Ln Aeric Haplaquods Murville fine sand Mu Typic Haplaquods Muckalee loam Mk Typic Fluvaquents Stallings loamy fine sand St Aeric Paleaquults Torhunta fine sandy loam To Typic Humaquepts Woodington loamy fine sand Wo Typic Paleaquults ' Source: (Barnhill, 1992) 2.4 VEGETATION Field reconnaissance was conducted to determine the HGM and plant community types within the GSRA. A brief description of the types identified is listed below. For a detailed account of each type, see the Phase I - HGM\HABITAT Model Parameter Selection report. Mitigation Bank Plan Page 5 1 GSRA Wetlands Mitigation Development 2.4.1 HGM Types Wet Mineral Flats Wet mineral flats within the GSRA consist of broad flat/depressional areas with no apparent inlets or outlets. These areas generally correspond to the pine savanna and wet pine flatwoods plant community types of Schafale and Weakley (1990). Non-Alluvial Hardwood Forest Non-alluvial hardwood forests within the GSRA consist of narrow linear headwater areas along first order drainages adjacent to wet mineral flats. These first order drainages feed into both pocosin areas and larger second and third order alluvial bottomland hardwood forests. The non-alluvial hardwood forest type corresponds to the Coastal Plain small stream swamp, nonriverine wet hardwood forest, and nonriverine swamp forest plant community types of Schafale and Weakley (1990). Pocosin Pocosin areas within the GSRA consist of broad organic flats or ombrotrophic bogs. These areas correspond to the low pocosin, high pocosin, pond pine woodland, and bay forest plant community types of Schafale and Weakley (1990). Alluvial Bottomland Hardwood Forest Alluvial bottomland hardwood forests within the GSRA consist of second or third order streams with a defined channel and alluvial features such as stream levee, drift lines, and sediment deposits. These areas generally correspond to the coastal plain bottomland hardwoods (blackwater subtype) plant community of Schafale and Weakley (1990). 2.4.2 Plant Community Types The plant community types described here are the result of field reconnaissance of GSRA and generally follow the appropriate community types outlined in Schafale and Weakley (1990) (Table 2). These plant community descriptions facilitated recognition of HGM types in the field and provided a framework for location of detailed HGM study sites. I Mitigation Bank Plan Page 6 1 I GSRA Wetlands Mitigation Development r t 1 J 1 Table 2. Delineation of HGM and community types and Subtypes at GSRA HGM Type' HGM Indicators Subtype Wet mineral flats Mesic - wet mineral soils lacking spodic (PF04E, PF03/4E) mineral flat horizon but may have organic streaking (Woodington, Plant community type(s): Stallings, Torhunta) - pine savanna - pine plantation - high landscape position - pond pine woodland - early successional mineral flat Hydric - wet mineral soils with spodic (mixed,pine,hardwood) mineral flat horizon (Leon, Murville) - frequently burned areas mapped as Croatan muck - high landscape position Pocosin (PSS313g, PF03/4Cg) ----- - thick organic soils or histic epipedon (Croatan) Plant community type(s): - lack of flowing water - low pocosin - intermediate landscape position - high pocosin - includes high and low pocosin plant communities Non-alluvial bottomland hardwood forest ----- - minimal or no evidence of (PFOIAB) alluvial features but with flowing/standing water Plant community type: - organic muck or wet mineral - mixed bottomland hardwoods soils (Muckalee, Woodington) - intermediate to low landscape position. Alluvial bottomland hardwood ----- - alluvial features such as natural forest (PFOIAB) stream channel, drift lines, water marks, & sediment deposits Plant Community type: - organic muck soils (Muckalee) - mixed bottomland hardwoods - low landscape position ' Wetland classification(s) in parentheses according to Cowardin et al. (1979) I Mitigation Bank Plan Page 7 t u GSRA Wetlands Mitigation Development Pine savanna Pine savanna within GSRA is characterized by scattered overstory pines (longleaf, loblolly, and pond pine) and a low understory (<I m) dominated by shrubs or herbs. Pine savanna occurs on wet to dry soil types. Common shrub species include inkberry (Ilex glabra), dangle-berry (Gaylussacia frondosa), and horse-sugar (Symplocos tinctoria). The dominant herbaceous species is usually wiregrass (Aristida stricta), but a variety of other species may be present. Pine plantation 1 1 11 1 ri Extensive loblolly pine plantations have been established within the GSRA. Pond pine has become established in certain plantations and generally survives following intense wildfires. Longleaf pine is not a component of these stands. Depending on the degree of wetness and fire history, a variety of understory types have developed. In wet stands with infrequent or low intensity fire a high shrub stratum of red maple, red titi, gallberry holly (Ilex coriacea), inkberry holly, fetterbush (Lyonia lucida), and swamp blackgum becomes established. In drier stands with recent fire a low shrub stratum (<1m) of inkberry, dangle-berry, horse- sugar, and gale-leaf blueberry (Vaccinium tenellum) develops. Pond pine/bay flat The pond pine/bay flat can best be described as a pocosin-like plant community over a wet spodosol (Leon or Murville series). This community is characterized by scattered pond pine with a sapling stratum of loblolly bay (Gordonia lasianthus), sweetbay (Magnolia virginiana), and redbay (Persea borbonia). In recently burned areas a low shrub stratum develops and resembles the low pocosin type. Characteristic species include honey-cup, fetterbush, red chokeberry (Aronia arbutifolia), red titi, gallerry holly, and dahoon holly (Ilex cassine). Pond pine woodland Pond pine woodland is characterized by a higher density of pond pine than that of low or high pocosin, sometimes forming a closed canopy. This community type occurs on shallow organic deposits (<lm) and oligotrophic mineral soils. The understory and low shrub strata are characterized by the same species found in the low and high pocosin types. Mitigation Bank Plan Page 8 P I GSRA Wetlands Mitigation Development Early successional flatwoods The early successional flatwoods type encompasses a broad array of recently disturbed plant communities. These communities have either been recently clear cut or burned by intense wildfire. Depending on the composition of overstory and understory species prior to disturbance, these communities are regenerating to a variety of flatwoods types (pine, hardwood, or mixed). The successional pathway of these communities will depend on a variety of factors including frequency of fire and site wetness. Low pocosin/high pocosin i d f h i h e vegetat on an t g t o These two plant community types are distinguished based on the he depth of organic layer (Weakley and Schafale, 1991). Low pocosins occur on deep organic deposits (>lm) and are characterized by a low shrub stratum (<1.5m ht.) of honey-cup, i fetterbush, red titi, dohoon holly, and galberry holly. High pocosins occur on shallower organic deposits (<lm) or oligotrophic mineral soils and are characterized by vegetation between 1.5m and 3.Om in height with scattered pond pine. The plant community is dominated by a high shrub stratum of loblolly bay, sweetbay, redbay, red titi, and dahoon holly with a low shrub stratum of honey-cup and fetterbush. Swamp blackgum forest The swamp blackgum forest type occurs within the alluvial and non-alluvial hardwood forest types. We concluded that this forest type is the result of "high-grading" or selective logging of large cypress and Atlantic white-cedar (Chamaecyparis thyoides) trees within these stands. Although some cypress and red maple occur as a codominant species, these stands are mostly dominated by swamp blackgum. The sapling stratum is usually dominated by red titi, red maple, sweetbay, swamp blackgum, redbay, and American holly (Ilex opaca). The understory is composed of Virginia willow (Itea virginica), highbush blueberry (Vaccinium corymbosum), sweet pepperbush (Clethra alnifolia), chain fern (Woodwardia spp.), and greenbriar (Smilax spp.). Mixed deciduous bottomland hardwood forest This plant community type occurs within the alluvial and non-alluvial hardwood forest types. In these stands swamp blackgum is present as a canopy species mixed with red maple, cypress, sweetgum, loblolly pine, sweetbay, and American holly. The sapling stratum is usually dominated by red titi, red maple, swamp blackgum, redbay, and American holly. The understory is composed of Virginia willow, highbush blueberry, sweet pepperbush, chain fern, and greenbriar. Mitigation Bank Plan Page 9 L 1 1 ri r, 1 GSRA Wetlands Mitigation Development Cypress bay forest Cypressibay forest occurs on shallow organic deposits and oligotrophic mineral soils. The overstory is dominated by cypress, loblolly bay, red titi, sweetbay, red bay, swamp blackgum, red maple, and pond pine. The understory is composed of those species found in the latter three plant community types. 2.5 LOCATION OF HGM TYPES Based on the extensive field data collected, 14 key locations were identified as being representative of the different HGM types within GSRA. Of the 14, ten are located within GSRA, three on main base (reference sites), and one within the proposed NCDOT right-of-way. Quantitative data was collected at all 14 sites and index equations developed for scaling the hydrologic, biogeochemical, and habitat functions of the different HGM types. From the detailed information, HGM types were then identified for areas within the training range clear zones identified on the GSRA master development plan (see Figure 3). Pine plantations dominate the HGM type which may experience impacts from range construction. Since a bedded pine planation is not a natural community type, replacing it was not viewed as the best alternative to benefit the over all system. In order to assess HGM functional values across wetland types, a direct comparison of the different HGM types was required. To accomplish this comparison, it was necessary to slightly modify the HGM approach currently being formulated by Brinson and Rheinhart. For an explanation of the HGM methodology and results, see the Phase II HGM\Habitat Model Functional Analysis report. 3.0 MITIGATION BANK DEVELOPMENT 3.1 INTRODUCTION The purpose of creating the GSRA Mitigation Bank is to provide compensatory mitigation for unavoidable non-tidal freshwater wetland impacts. The goal of the Mitigation Bank is to provide benefits on a system-wide basis by returning a more natural hydro period to the mitigation areas which in turn will enhance the associated downstream systems. The hydrologic regime of the major drainage systems, Holly Shelter and Juniper Creek Swamps, has been severely altered by the past forest management practices. The systems are "flashy," that is, stormwater runoff is conveyed through and offsite in an expedient fashion. Subsurface water storage is limited, leading to higher fluctuation in groundwater levels than natural systems. The Mitigation Bank constitutes a portion of the headwaters of both systems. By modifying the current drainage patterns back to a more natural state, the stormwater will have a chance to infiltrate and discharge over a longer period of time. Mitigation Bank Plan Page 10 1. 1 1 1 r f 1 1 1 1 Ll 1 LEGEND CUTOVER / BURNED - MGM DESCRIPTION PINE (PF-4) . MGM DETAILED PLOT ASSIGYEN PLANT COYYUNTITES / MGM TYPES ABH(C) ALLUVIAL BOTTOMLAND HARDWOOD FOREST (CHANNLIZED) NBH - NONALLUVIAL BOTTOMLAND HARDWOOD WMF H/D) WET MINERAL FLAT/HYDRIC/DITCHED WYF(Y3 WET YINERAL FLAT/ MESIC POC D POCOSIN DITCHED Dw6ow ! awls FIGURE 3. HGM TYPES WITHIN GSRA wr To mu 1 1 1 1 GSRA Wetlands Mitigation Development The proposed GSRA Mitigation Bank consists of three restoration sites; two are located in and adjacent to the southern portion of the south pocosin. The third is located south of Range P-933 within the Big Shakey Swamp (see Figures 4 and 5). All three areas are extensively ditched and the burned pine plantation area has only sparse vegetation. An existing road (Watershed Road) bisects the pocosin and burned pine plantation areas. The road acts as the high point and water drains from it to both the pocosin and pine plantation. The pocosin area drains to Holly Shelter Swamp, whereas the pine plantation and Big Shakey Swamp areas drain to Juniper Creek Swamp. The Big Shakey Swamp area will be restored\enhanced by placing timber dams at 400 foot intervals within the existing channel. The dams will allow the system to detain water and realize overbank flooding conditions similar to the historical natural state. The pocosin area will be restored by placing ditch plugs at key points throughout the extensive ditch network. The plugs will help elevate the groundwater back to the levels experienced prior to the area being drained for silvicultural activities. The surface and groundwater levels in the burned pine plantation will be enhanced by plugging the existing ditches at key locations and by placing a temporary water control structure at an existing culvert location. This combination will allow the natural hydrology to return, while allowing the actual surface water level to vary based on actual field conditions. This feature is important as this area will also be replanted with cypress and various oak and pine species. The vegetation planted will need time to become established prior to completely inundating the area. The planting plan calls for a bottomland hardwood area surrounded by a combination of pond pine and long leaf pine. A more detailed account of the remediation measures for the Mitigation Bank may be found in Section 3.5 of this plan. The restoration sites contain the following acreage: Restoration Site Area (acres) High/low pocosin 886.8 Burned pine plantation: Pine Flatwood 135.5 Bottomland hardwood 84.8 Big Shakey Swamp 143.4 Total 1250.5 1 I Mitigation Bank Plan Page 12 1 1 1 1 1 1 1 C V 3 Z > o a?i ? J v C7 U p Z ° I Q N z W F n w It U a Q m z s r W QO W z to ?O 8 z - _ j L L- 3 U) - d W d = M 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 U ? Z N L J a? 0E U Z Z`ZZ w J 0 W Z Z Of ¢ gZ O Lo r ?- Lj 0 m Q LLJ O O 03 dcr W 0 3 rr Z V1 I W W 2 ? J m D JAJa oZ W N ?C) WN " ?ZZ = m z Q U.Q. Cl- Of N m Q o ? V) 0 W N w J Y W Q Z = Z N I (N a U m CL = m m to Q Z. i r V) W Y ? a W = Z C? m 1 L? 1 1 1 GSRA Wetlands Mitigation Development 3.2 HYDROLOGY There is an ongoing groundwater hydrology study being conducted for the proposed Mitigation Bank. The latest hydrologic monitoring report covers the timeframe from, 1 February to 1 July 1996. In addition, this baseline data can assist in determining the remediation requirements necessary to restore each area to a fully functional wetland. Figure 6 shows the location of the wells in the proposed mitigation and surrounding areas. Based on the well data, the majority of the proposed pocosin mitigation area would not meet the hydrologic requirements to be classified as a wetland during the "normalized" rainfall periods or during any portion of the data collection period. The only wells which met the Corps criterion during the latest timeframe were 21E, 21I, and 23A. This was due to the placement of ditch plugs in the vicinity of these wells during the winter of 1995 and spring of 1996. The pocosin reference wells 1 and 2 have qualified as meeting the requirements since the inception of the monitoring program, with well 2 also meeting the criterion during the latest timeframe. By reviewing the data for reference wells, a distinct difference can be noted in the groundwater levels and the reaction to a rainfall event for these areas versus the ditched pocosins (see Figures 7, 8, and 9). The reference areas maintain a groundwater level near 12 inches below surface on a regular basis which then rises in response to a rainfall event and maintains that higher level for a longer period than the ditched areas. The proposed burned pine plantation mitigation area showed the tendency to have wetland hydrology at the initiation of the monitoring period in October, 1994 and during the spring and early summer of 1996. The data reflects that the northwest corner of the mitigation area does meet the Corps hydrologic criterion. A field inspection yielded that this area normally would be drained by a ditch system and downstream culvert, but due to lack of maintenance and debris blocking the culvert, the drainage system is not functioning properly. The mitigation area downstream of the culvert is visibly drier. This observation leads to the conclusion that plugging the ditches and/or placing control structures at culvert locations will effectively restore the hydrologic regime to the entire mitigation area. There are nine monitoring wells located within Big Shakey Swamp. Wells 13-1 through 13-8 during the first full year of monitoring, showed that during periods of normal rainfall, the area would not meet the wetland hydrologic requirements. The well data also indicates the ditching pattern successfully drains the area quickly. In periods of higher than normal rainfall, the area has a tendency to remain wet for longer periods of time. This may indicate the ditch capacity is exceeded and the excess water is discharged into the overbank areas. By strategically plugging the ditches, this overbank flooding should occur on a frequent basis, returning the natural hydrology to the system. During the monitoring period from 1 February to 1 July 1996, wells 13-2, 13-3, 13-5 and 13-7 displayed wetland hydrology. All of these wells measure the groundwater, whereas wells 13-4, Mitigation Bank Plan Page 15 1 1 1 1 F] 1 1 1 GSRA Wetlands Mitigation Development 13-8 and 13-9 measure surface water. This is important to consider since the latter wells are located nearest the channel and do not meet the hydrologic criterion. This indicates, for this region of the mitigation area, that the channel is adept in lowering the water table and reducing any potential surface water storage.. To evaluate the effectiveness of the channel on water table Drayton, a brief DRAINMOD model was developed by Dr. Devendra M. Amatya. This study indicated that for about 2.1 inches/day of precipitation runoff, the channel could reduce the water table elevations for a distance of approximately 200 feet. Based on the results of this study and field observations, the ditched area north of the southern most well transect ( wells 13-1 to 13-4), could be enhanced by placing timber dams at about 400 foot intervals. The limits of the enhancement area are set at a distance of 200 feet from the centerline of the channel. While the mitigation area located south of the referenced well transect has not been monitored, field observations indicate it is significantly drier than the northern area. For this area, timber dams will be placed at approximately 400 foot intervals. This should allow for longer detention time, greater overbank flooding and increase the water table elevations. The historic mapping for the Muckalee Loam (Mk) soils series has been used as a guide in establishing the boundaries for the southern two-thirds of the mitigation area. The mitigation area varies from the Mk soils boundary to include two tributary fingers. A distance of 200 feet from the centerline of each tributary was established for these areas. The upper extent of the finger areas were limited to the historical floodplain limit. To the south of the tributaries, the mitigation area was set using a combination of the Mk soils line and a distance of 200 feet from the centerline of the channel. As before, the extent of the mitigation area was limited to the historical floodplain limit. This mitigation area will be monitored for both surface water inundation and groundwater levels. It is the intention of MCBCL to enhance and continue intensive monitoring of all three mitigation areas. The monitoring will continue through the entire period of restoration activities, culminating when the Corps Hydrologic criterion is met. Mitigation Bank Plan Page 16 1 1 1 1 1 1 i 1 1 1 1 1 1 1 1 1 1 1 1 C/) o cn OS6 U p < Z w 3 M C7 g Z w J O z U) a: L, 0?a0 03 w In J 3 ; LLZEr ? 0 (? ? Q ~ Q Z O s 2 Rk gYg esw ? 3 Y • ??, s ; !L. ?? = E ? s a i : ab3 ?? a ` s 0 9 • Q' 6 w W w N U ? ?• J; w 3 K { 3 a a 0 w o CL ?- w c • O s z O Z O F u 0 0 O T N,C. RT, w 50 u : 0 s N 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 GSRA Wetlands Mitigation Development (sepui) JJBJUIBa ?i. M ? 1 i\ >'N CD CD Q 3 o? mr cc 3> m 10 -4ew-80 CO 56-Jdd 6Z O LO Figure 7 -- Pocosin Reference Well #2 Source: Geo-Marine, Inc. Multi Project Mitigation Area Plan Page 18 CV Cn It (say0ui) yldea 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 GSRA Wetlands Mitigation Development (seyoui) llejuiea L O d' M N O 'S6-?eW-9l M 56-AeW-60 a M Uy- 0 V 56-?ceW-Zp ? ROD (D CD 0D 4-0 e v ss-ode sz O O O O O O O' S fi-Jdy-g L N CY) Lid (seyoui) yjdea Figure 8 -- Pocosin Reference Well #3 Source: Geo-Marine, Inc. Multi Project Mitigation Area Plan Page 19 1 1 1 1 1 1 1 1 1 1 1 1 1 1 i 1 1 1 GSRA Wetlands Mitigation Development (sayoui) lle juiea LO ct M N O 96-AeW-O L 56-AeW-£0 oa N Q ? L m> 2 56-Jd"Z 56-Jctd-6 L 96-Jdd-Z L G v CO 96-Jdvf-9O m s6-JeW-6Z CO g6-JeW-ZZ o : 56-JeW-S L R 56-JBW-80 96-JeW-LO O O O O O O O N CV) LO (say0ui) yldaQ Figure 9 -- Pocosin Reference Well #12A Source: Geo-Marine, Inc. Multi Project Mitigation Area Plan Page 20 GSKA Wetlands Mitigation Development 3.3 VEGETATION The pocosin and hardwood bottom areas have established vegetation similar to that described in Section 2.4. Selective logging in the Big Shakey Swamp has slightly altered species composition. The majority of Atlantic white cedar and large cypress have been removed, leaving swamp blackgum as the dominate species. The pine plantation area burned in August 1993. Figure 10 is a photograph of the area taken in April 1994. 3M 'r, rr F ' .`R. Figure 10 -- April 1994 Photograph of Burned Pine Plantation Area This area has some natural regeneration but is largely dominated by bracken fern. Llulti Project litigation Area Plan Page 21 I GSR,4 Wetlands Mitigation Development 3.4 SOILS There are six types of soils within the proposed Mitigation Bank, Croatan muck (Ct), Leon fine sand (Ln), Torhunta fine sandy loam (To), Muckalee loam (Mk), Murville fine sand (Mu), and Woodington loamy fine sand (Wo) (see Figures 11 and 12). All of these soil types are considered hydric by the ' National Technical Committee of Hydric Soils List. The vast majority of area is Crotan muck, a nearly level, very poorly drained soil. Infiltration is moderate and surface runoff is very slow. Permeability is moderate and available water capacity is high. This soil has a high organic matter content in the surface layer and has high volume change when it dries. The seasonal high water table is at or near the surface. This soil is subject to rare flooding. Torhunta's soil characteristic are similar to Croatan muck, with the exception of ponding water on the surface during the winter months. Muckalee loam is a poorly drained soil located on floodplains. It has the same infiltration and permeability characteristics as Croatan muck, but its available water capacity is medium. The organic matter content in the surface layer varies from high to low. The seasonal high water table ranges from 0.5 to 1.5 feet below the surface. Murville fine sand has the same infiltration, permeability, and water capacity characteristics as Muckalee loam. Organic matter content in the surface layer is high. The seasonal water table is at or near the surface and water ponds on the surface during the winter. Woodington loamy fine sand is similar to Murville with the exception of the seasonal high water table ranges from 0.5 to 1.0 foot below the surface and is only subject to occasional ponding of surface water in low areas. Leon fine sand is a poorly drained soil usually located on uplands near broad interstream divides. Infiltration is rapid and surface runoff is slow. Permeability is rapid in the surface layer and moderate in the subsoil. Available water capacity is low. The seasonal high water table is at or near the surface. ' The fire which occurred in August 1993 burned away the peat layer (Croatan muck) in the pine plantation area. The substrate now consists of mostly mineral soil. Given the loss of 6 - 8 inches of soil in the fire, restoring the hydrology to the area may actually result in surface flooding and open water in the area. To minimize any potential flooding problems, the water levels in this area will be controlled by ditch plugs and\or water control structures at culvert locations. The ditch plugs and water control structures can be adjusted to accommodate for field conditions present throughout the restoration period. The soil types identified have and are capable of supporting the proposed wetland systems. 3.5 REMEDIATION MEASURES 1 1 3.5.1 Drainage Ditch Alteration Each mitigation area: pocosin, burned pine plantation and Big Shakey Swamp, have been thoroughly ditched and drained. Ditches in the pocosin and burned pine plantation will be plugged at locations which correspond to about a three inch difference in gradient (see Figure 13). The ditch plugs will be constructed using on-site bank spoil whenever possible. If necessary, borrow material of sand/loam and sand/sandy loam composition will be imported. The ditch plugs will be armored with rip rap for protection against the anticipated higher water levels. In addition to the ditch plugs, a temporary water control structure will be placed at an Mitigation Bank Plan Page 22 1 I GSRA Wetlands Mitigation Development existing culvert location within the burned pine plantation (see Figure 13). The water control structure incorporates pvc pipes at multiple elevations such that surface water elevations can be manipulated at six inch intervals. Depending on how the system responds to the initial controls placed, a key ditch plug can be modified to include surface water control (see Figure 13A). Once the desired water level is achieved, the water control structure(s) will be replaced by a permanent earthen dam constructed to the identified elevation. The dam will be constructed out of the same materials as the ditch plugs. Timber dams will be placed in the drainage ditch bisecting Big Shakey Swamp (See Figure 14 for dam locations). The dams will be constructed out 6" x 6" pressure treated timbers (see Figure 15). Timber dams are a permanent, low maintenance way to promote greater detention and over bank flooding. Minor adjustments of the dams, either in location or vertical height, can be made depending on how the system responds to the initial dam placement. I I 1 1 1 Mitigation Bank Plan Page 23 t 1 1 1 1 1 b 1 1 1 i t 1 1 Z z zZ cU ? Z¢3? 0 8:5 C V a W W c. Z 2 H d W Q 0 vv z Nam G?odZJ ?J 3 ?W 00 OWQN E a. z (n v o cr C9U am?z z ??? Z J c J ?Z C ?r p J g z G d U J _ZO~ c C J a J U a O CL O o r U c = J c J ? W Z C.) ?y J C C9 J w z Z O z o- a. qto z"m !3 O H O H W z z z O Y O H ?' 3 ti O O 3 H U O LL. O Z +' 4 a H Q G. 1 1 f 1 1 t 1 U Z C v d N 'y L- J 0) vE a? r W 2 W 3 o uj ? QZ J 0 ,,, D W M F- J 4. W N N 0 a..oX a.?z A 1 1 1 r 1 P-j z Z Z Z O = Z o N 5 °? ? I Q ?O 5 Z o C ) < g n >? Z ?- w ?O?Q- ? e T N p p o z v a s Z I U a- w J C: 7 C) Zo 3a W O W C , z O ? m t: _ 0 Of Z cn° W w a- Wa 7 D z - W = 3 0 Z::D J J J x m x O s w IL 3 (_? Lli a- O a 3 N ? ? I 1 1 Q = O L o o xz(? . . ti 0z C7U OfC) m z --?0 z? _ Jc? vz J :D - L J = pOfL j .? ? Dd z Z I/ Z 1 a x m W o ? / ? i / - J ? ? Z a a _ /I I i I / ? h? U ? I I I / ? Z NW I/I / /? z III 0 Q / Na N , / O / z e w 0 // . i u w ji = U Z? U Q = / Wa ? ? VI QU Y 3 V W V r Z a a / // /? 1 LLJ ` W a 5 0 W z N go>2 ZK I? 1 ~ QIz ? d0 W Z ~ / I LL LJ Z D L . z I 0 ? . Z a. `/?1 I / L_L 1 I I/ - `O? / Q i / 0 0 I O / 1 i ' f i--? ? ? < i / - 1l N H- DO: ice' ??Q'?? ?? ? ?\ I _ ----- / z / / Q.. a- c? 1 1 i % ? ? ? O ? ? `? ? ? ? ?? ?? ? ?? ?? ?? / V) Z w O U Q U Z w ° o U a O ¢ : co , p ° z w J Z 0 O a: Q I I U W O° p i Z J Q ?ZW O z l W Q c0 X N W W C? D7 o W = Q WI Q p J =I p 0 v F- W UI W C, z 0 CL cc 0 (n F- p j _ w ' O C N M -Lnl 3dld ??d „Z L 3NM331N33 '? F• I . I Z Z O l W o MMJ v o ? U o (d)ll) 3dId ?d „9 3N1-12J31N33 W > Q d O 0 C 0 17 C) _ ? D UI T v J ° Z Q U = ? a_ U W n a_ E z _ ° O 0 U U Z Q CD >OZ ° W W .-. W 0 ?i b LLJ 0- Q U ZI o F ° O o 3: Q U ? W ° ccl I o ? a. W W -? ° Q > W a_ Q ?I -.• W ,i o M MA N, _ W 0- i o C'3 > I LLLJ J o o _ 0'I ip I/ a_ UI F- 01 1 1 t r U ? z v c J a? v C7 U z ° za Zo gZ? QU Q{ 3 H W o o< J O '- W r-acr Z =Z o IWtrm0m?0 RIC ?- ? 3 Of z NO 00 ap? 0 Br. 3:: 0 a0: 204 > Z dop 1 m a o VI r? 1 w v I Y ? m • I a / ru 2 O w t 1 r 1 1 I zg 41 11 i < bi'j- a ° Z will cb$ La W La W gild! M? v N n N F- 2 _ = O _ O F J J W W Z Z cr O 3 = U O +,£•xoadde-? GSRA Wetlands Mitigation Development 3.5.2 Planting Plan The overall Mitigation Bank is composed of three mitigation areas, and only the burned pine plantation area will be subjected to vegetative restoration. Remediation measures for this area will be accomplished in the following sequence: T 1) Adjust/maintain drainage system to dry out entire Mitigation Bank. 2) Provide planting sites at ten (10) foot intervals by use of a v-plow to offset coarse woody debris into the inter-row position. Use of a harrow may be required to restore soil tilth within the planting rows. 3) Plant vegetation. Vegetation will be planted by hand. 4) Plug ditches as indicated in Section 3.5.1. Due to the loss of 6-8" of soil in this area, it may be necessary to postpone the plugging of ditches until the plantation is deemed able to withstand increased soil saturation/inundation. Groundwater levels in this area may need to be adjusted to avoid excessively wet conditions. Based on an inventory of the reference pocosin and pine flat and bottomland hardwood wetland systems, a planting prescription of overstory tree and shrub species will be planted r. in Pond Pine, Longleaf Pine, Cypress, Water Oak, Overcup Oak and Swamp Chestnut Oak. Plants will be established at a 6 x 10 foot spacing (726 plants/acre). Tree and shrub mixtures will be matched to specific hydrologic strata within the planting area. Species mixtures will follow elevational gradients to simulate natural tolerances to wetland conditions. r 1 Our strategy of planting 726 tree/acre should provide adequate insurance of meeting the required plant survival even under severe abiotic and biotic conditions. No ground cover plants will be planted given the potential seed viability within the surface soils. It is likely that there will be high germination of indigenous pocosin shrub species and ground flora due to frequent flooding events and close proximity to propagules. Based upon species composition of overstory trees on reference sites, a planting guide is provided in Table 3 and Figure 16. 11 Mitigation Bank Plan Page 30 1 GSRA Wetlands Miti ation Development 1 1 1 1 1 Table 3. Relative Species Mix for Burned Pine Plantation Mitigation Site Majority Pond Pine & Cypress and Multi Species Long Leaf & Long Leaf Pine Water Oak Bottomland Pond Pine Combination Hardwood 73.7 Acres 61.8 Acres 13.1 acres 71.1 Species Plant Species Plant Species Plant Species Plant Type Per Type Per Type Per Type Per Acre Acre Acre Acre Long 544 Long Leaf 97 Cypress 581 Cypress 73 Leaf Pond 97 Pond Pine 629 Water Oak 145 Water Oak 218 Pine Willow Oak 145 Swamp 145 Chestnut Oak Overcup Oak 145 The species listed in Table 3 were chosen for their compatibility to the hydro period and fire regime intended for this area. It has been noted that fire management will be part of the concerns of operation the Mitigation Bank. Excessive fuel loads in conjunction with training and operations activities would provide a potentially hazardous situation for MCBCL personnel. Therefore, species such as Atlantic White Cedar were not considered due to their intolerance to fire. 1 I Mitigation Bank Plan Page 31 1 1 r 1 1 r 1 1 1 1 1 1 1 cU 3 Z v a?i ? J vE C7 U z $ 3 W oZujw. ?- Z g :5 to Z CI- z? Z i $ z rn s w ?waZ -tj gg 8s 3 0za? I R E D - U- Z p Cf3z? of Igo ? m m r r \ z0 , % ` ?%`` .? % % i i L/l 100, -uj a- CL .,i- 1 .1 ` *4b w 1 GSRA Wetlands Mitigation Development Use of Preemergent herbicides will be applied by a licensed applicator in strict adherence to labeling following planting. In every instance, the planting stock will be obtained from the State Forest Service and/or forest industry nurseries. The seed sources for the plant material will be obtained from within the North Carolina Coastal Plain, and when available, genetically improved seedlings will be obtained. Only the highest quality 1/0 or 2/0 seedlings will be obtained for planting. The seedlings will be hardened with well developed fibrous root systems and healthy buds. At the nursery, seedlings will be packaged in groups of 100 to 200 in Kraft seedling bags. Bags will be stored between 1 to 4° centigrade making certain that the temperature does not dip below freezing. Planting will be conducted during the dormant season. In all cases, a MCBCL staff member or qualified consultant will be on site to supervise the planting job. 3.6 MONITORING Background Monitoring provides an accounting of ecosystem processes to ensure that functioning wetlands are established. This is an important Mitigation Bank objective. Performance of the Mitigation Bank is assessed by comparing monitored data from mitigation sites relative to undisturbed, reference wetland habitats. The intensity of monitoring varies with the degree of disturbance at the Project site and the probability of successfully achieving targeted wetland functions (White, et al., 1991). Our monitoring program will evaluate structural and functional indicators of each wetland parameter of the mitigation effort. Plot locations for monitoring of vegetative mitigation success criteria will be co-located with selected groundwater monitoring wells (see Figures 14 & 17). At each selected well location a vegetation plot will be established to baseline initial conditions. Three additional wells will be established in an undisturbed sister drain of Big Shakey Swamp with comparable watershed characteristics and drainage basin size (see Figure 17A) to aid in comparing the hydro period for the restored Big Shakey Swamp to a natural system. 'L 1 1 Mitigation Bank Plan Page 33 1 1 1 1 1 1 1 w 1 1 t U Z T 4) v a?i y ? J °E C7 U f?i z Z ? s F ? 4 ? w ° Z +(A 3 zzoo <pKa Z?<- o o O g 2!R z v)a01-O w? ?aw?c9Q LL. N 30-J a° 0w N Q Oaw? ama3 1 J W Z 3aa za3 a'Z W ncor H N O G H° W ZQ N Q C 3 N'?y g-2ZN ?J 3 Z ? N O in ,v 0 'D E L- 0 O V 'o a? t\ \ 1 ti i 1 11 1 1 1 1 GSRA Wetlands Mitigation Development 3.6.1 Mitigation Implementation Sequence Following is the mitigation implementation sequence for the Mitigation Bank: ? Location and full description of monitoring plots. ? Final planting map showing planting zones by species within restoration areas. ? Establishment and location of groundwater monitoring wells. ? Location of vegetation sampling plots. - Measurement of vegetation will be based on 1/20th of an acre plot size and will include the information gathered on the following field data sheet. VEGETATIVE MONITORING DATA SHEET Researchers Transect ID Recorder _ Plat Number GENERAL What cover type is present (According to Cowardin et al)? If Upland, specify type (i.e. Pine, Planted Pine, Field) Date If forested, most trees are (D.B.H.): <6" 6-18" >18" TREE LAYER (Consists of woody plants > 20 ft. Tall, excluding vines) Average Height of all Trees (estimate representative tree) Ft. Overstory Trees (At Least 80% of height of tallest tree) Other D.B.H. Estimates (to nearest r- T- Mean density of trees per acre Mitigation Bank Plan Page 36 1 i 1 1 1 f A 1 1 ?l 1 1 GSRA Wetlands Mitigation Development Understory Tree (Less than 80% of height of tallest tree) D.B.H. Estimates (to nearest r- 7-- Mean density of trees per acre SHRUB LAYER (Woody plants 3-20 ft. Tall; including vines) HERB LAYER (Herbaceous plants, 3 ft. Tall) PERCENT COVER (Visual Estimates) Canopy cover of all trees Canopy cover of overstory trees Canopy cover of understory trees Canopy cover of shrubs Canopy cover of trees and shrubs combined Percent cover in the ground layer: (Less than 3 feet above the ground) Overall litter depth in Number of tree stumps (> 6 in diameter, > 1 ft. tall) Number of logs (> 6 in diameter, > 3 ft. Long) _ Mitigation Bank Plan Page 37 Leaf litter _ Woody debris Live vegetation 1 1 r Ll 1 1 f A 1 A GSRA Wetlands Mitigation Development SNAGS (D.B.H. Estimates, must be at least 6 ft. Tall) HYDRAULIC FEATURES Is there evidence of standing water on the plot? Yes No Max. Depth Are the following present on the plat? Water Marks Yes No Drift Lines Yes No Sediment Deposits Yes No Drainage Patterns Yes No Water Stained Leaves Yes No Other (explain) A description and verification of hydrological connections Approval of the Mitigation Implementation Record Notebook Mitigation work will be done by Camp Lejeune personnel or a qualified contractor as appropriate. 3.6.2 Mitigation Implementation Record A written Mitigation Implementation Record (MIR) will serve as a record for all activities during construction regarding soils, hydrology, and plant establishment. This MIR will be in notebook form with all tasks clearly defined by tabs and will be submitted to the appropriate regulatory agency(s) following completion of each of the tasks. All monitoring data will be summarized and graphically presented for submission as part of the MIR. Initial work will include evaluation of the Mitigation Bank for compliance with the design criteria and for agreement with permit conditions and Mitigation Bank objectives. Baseline data has been collected on the Mitigation Bank location: hydrology, substrate, and vegetation. Differences between the design and actual implementation will be documented during the Mitigation Bank's implementation phases and mid-course corrections will be made as necessary. Modifications to the original design are often necessary as unexpected conditions are encountered. When necessary, such changes will be noted and brought to the immediate attention of the regulatory agencies and new/revised Mitigation Bank specifications submitted as part of the permanent record for the MIR. Once the as-built assessment is complete, differences between what was planned and what was built will be evaluated by the permitting agencies. If modifications to the Mitigation Bank are necessary, the as-built assessment will be updated in the MIR to reflect these Mitigation Bank Plan Page 38 1 1 GSRA Wetlands Miti ation Development changes. When the evaluation is final, the as-built assessment will become the permanent record in the MIR to enable comparison with future Mitigation Bank assessments. Obtaining functional wetlands on the restoration portion of the Mitigation Bank will require measurement and analyses of the following: 1 3.6.3 Hydrology Water depth will be measured in the mitigation areas both as a function of inundation above ground, and depth below ground using wells constructed of PVC plastic, equipped with pre- programmed data recorders to read water depth four times daily (at 0600, 1200, 1800, and 0000 hours) with a 128-day wrap-around monitoring cycle. The micro-processor electronic components and power supply are all enclosed within the weatherproof head portion of the device. Well locations have been established on the site which encompass the slight variation in topography, soils, and distance from perimeter ditches. Indirect indicators will also be recorded according to the Federal Interagency Committee for Wetland Delineation, 1987 Federal Manual for Identifying and Delineating Jurisdictional Wetlands (W.I., 1991). Measurements will occur weekly (initial growing season) following installation of monitoring wells for the first year, and at two month intervals (dormant season) and weekly (growing season) until regulatory release. Rainfall events will be included within the MAR. to facilitate a correlation of precipitation conditions at the time of well measurement. 3.6.4 Soils In the Mitigation Bank, soil taxonomy will be determined by excavation of a pit to depth of flooding. Mainsail color will be determined for chrome and hue for both matrix and mottles (W.I., 1991) for each soil horizon to a depth of 40 inches at each sample plot location. Soil texture will be determined for each soil horizon using textural triangle and based upon feel. Soils will be classified into the appropriate series. All soil amendments such as fertilizer or lime (if applied) will be documented and activity monitored by soil analysis. 3.6.5 Vegetation Tree planting locations and establishment requirements are included in this mitigation plan (see Sections 3.5.2). Survival, numbers of stems per acre by species, and tree height will be measured at the end of each growing season as part of the vegetation analysis just prior to leaf fall for the duration of the monitoring period. 3.6.6 Observation The Mitigation Bank will be photographed from permanent photo stations and changes in any of the above variables will be recorded and included in each MIR annual report. The cost of post-construction assessments varies dramatically with the methods and intensity Mitigation Bank Plan Page 39 1 1 GSRA Wetlands Miti ation Development of data collection. To obtain acceptable accuracy at a reasonable cost, the establishment of permanent sampling plots at selected monitoring well locations will be used to facilitate routine assessments. Visits to permanent plots in wetland forest creations or restorations are not likely to significantly affect the physical integrity of the wetland for any of the assessment proposed in this plan (Candela et al. 1992). Sampling in these plots will be nondestructive. Sampling stations will be established within planting unit subdivisions (e.g., pocosin, pine flatwood and hardwood bottom habitat types).. An annual report summarizing current year's assessments and monitoring data will be submitted to the Mitigation Bank Review Team (MRBT) each December. Additionally, the report will include the groundwater monitoring data for each individual well. The report will indicate if corrections are required or if more comprehensive monitoring is needed to interpret wetland conditions. The report will also document significant changes at the site from the as-built conditions since the last routine assessment was submitted. The annual assessment should be filed with the permanent Mitigation Bank records so that it is available for future reference. Following the review of the Annual Reports or field review by the regulatory agencies, modifications may be recommended for implementation. 3.6.7 Success Criteria Monitoring efforts will continue for five years or until the following standards are attained, whichever comes earlier: u 1 1 1 I Vegetation For the burned Pine Plantation Mitigation Area, a mean density of 320 planted trees per acre are growing within the burned pine plantation mitigation site consisting of the preferred canopy species which average 3 years of age, based on a permanent 1/20th acre circular plots at each monitoring station. Natural regeneration recruitment by species will also be measured using the same circular plots. Any changes to the vegetation composition of pocosin, pine flatwood or hardwood bottom systems will be noted. Hydrology Big Shakey Swamp, Pocosin and Burned Pine Plantation Mitigation Areas: Hydrological conditions, as determined by visual observation and monitoring wells will meet the 1987 Corps Manual. Mitigation Bank Plan Page 40 1 GSRA Wetlands Mitigation Development 4.0 MANAGEMENT PROTOCOLS 4.1 CONTINGENCY PLANS When implementing this mitigation plan there may be circumstances beyond normal mitigation practices that requires additional effort and the possible outlay of resources. Experience over the years has indicated that occurrences such as herbivory of planted seedlings, intense competition by herbaceous growth, fire, storms, drought, etc. can compromise stated success criteria. Therefore it is essential to be able to manage for the occurrence of such unforeseen circumstances before the mitigation project becomes a failure. Several of the most frequent contingency actions are identified below: 4.1.1 Herbivory There are many examples of mitigation projects where herbivory reached critical levels and rendered all planting attempts useless. The best way to manage such problems is to be cognizant of all potential pests. Beavers, nutria, rats, rabbits, insects, and deer can all be controlled, but they must be closely monitored by continuous on-site reconnaissance during the entire establishment period (2 to 3 years). Beavers and nutria must be eliminated if succulent seedlings are to survive on sites adjacent to potential water courses. Rats and rabbits are best controlled by raptor predation by keeping the planting row free from vegetation. Selective herbicides used following planting are best suited to ensuring rodents are controlled naturally during the initial establishment years. Many times a follow up herbicide application is necessary to ensure rats are controlled into the second growing season. Insects can significantly limit initial growth attainment of planted seedling, but rarely kill mitigation plantings outright. When insects prove to be a constant threat to planting stock, appropriate pesticides can be applied to ensure adequate control. The key to managing insect herbivory is not to overreact and make an unnecessary application that have other deleterious effects elsewhere in the ecosystem. Deer are obviously best controlled by hunting. On sites where hunting is not a viable option, solar electric fencing has proven quite effective. 4.1.2 Fire The best way to manage wild fire is to have the mitigation site incorporated into a forest management plan that has a comprehensive way of dealing with wild fire. At the GSRA site there are adequate measures already provided that will attempt to limit the destructive forces of fire. These measures include prescribed fire and Best Management Practices for fighting wild fires. During high hazard periods the GSRA will come under the same oversight that all of the other Base holdings are subject to. If fire does kill mitigation plantings, the site will be assessed for survival and reestablishment of vegetation will be undertaken. fl Mitigation Bank Plan Page 41 L GSRA Wetlands Mitigation Development 4.1.3 Noxious Vegetation There is no way of predicting the types of vegetation that might become established on mitigation sites. The best control of noxious growth is to predict early competition of weeds and by using selective herbicides at the time of establishment within the planting rows. Several herbicide applications may be necessary, but moderation should be shown given the beneficial effects of having the site totally vegetated and the protection that light competition afford the newly planted seedlings. 4.1.4 Drought/Storms Early and prolonged drought during the growing season can render any planting attempt a failure. Survival after the first year will have to be assessed and replanting considered if survival approaches success criteria. Prolonged storms can often have the opposite effects of drought by inundating seedling and eliminating the possibilities for normal growth. There is often little that can be done to eliminate excess water given the location of most mitigation sites close to the water table or open water. In stances where storms knock out ditch plugs or other structures, a post storm assessment needs to be made immediately to ensure that appropriate measures are undertaken to ensure hydrologic criteria are met. Remedial activities will be reported to the Corps of Engineers to ensure modifications are consistent with overall objectives of the mitigation project. 4.2 NATURAL RESOURCE MANAGEMENT Camp Lejeune's Multiple Use Natural Resources Management Plan has been a highly effective means of coordinating the various natural resource elements that Camp Lejeune must manage. At Greater Sandy Run, the key elements to natural resource management will include forest and wildland fire, endangered species, wetlands, cultural resources, and wildlife (game and non-game). Execution of Camp Lejeune's natural resource plan is done largely through the proper review and coordination of the base forestry operations, managed by Camp Lejeune's Forestry Division. To ensure continued effectiveness in coordinating Camp Lejeune's natural resource concerns, Camp Lejeune will integrate the GSRA Mitigation Bank into its Multiple Use Natural Resources Management Plan and Camp Lejeune's forestry operations. This will allow for the most effective means of establishing successful pine plantations hardwood bottoms, fire management, and endangered species management. 4.3 MITIGATION BANK INSTRUMENT This Mitigation Bank will require an instrument as documentation of agency concurrence on the objectives and administration of the area. The instrument for the GSRA Wetland Mitigation Bank will describe the physical and legal characteristics of the area, and how the area will be established and operated. It is envisioned that a Memorandum of Agreement (MOA) will be signed upon I Mitigation Bank Plan Page 42 GSRA Wetlands Mitigation Development acceptance of this mitigation plan by the area sponsor and signatory agencies. Whenever this area is to be used for wetland filling discharges requiring Section 404 authorization, the MOA will become part of the permit. 4.4 CREDITING/DEBITING/ACCOUNTING PROCEDURES Credits represent the accrual or attainment of aquatic functions at the Mitigation Bank; debits represent the loss of aquatic functions at an impact or project site. Credits are to be debited from this area when they are used to offset aquatic resource impacts requiring Section 10/404 permits. The Hydrogeomorphic method approach for wetland functional assessment was used to determine the debit ratios required for proposed discharge activities in aquatic resources. The HGM functional analysis quantitatively adjusted the ratio's established for the Mitigation Bank as follows: Pocosin restoration site: 1:1 Pine Flat restoration site: 1:1 Bottomland Hardwood restoration site: 1:1 General Guidelines published by EPA recommend a 2:1 ratio for restoration activities. This suggested ratio is general in nature and was not intended for inclusion in every mitigation strategy. In fact, the proposed pine flat Mitigation Bank is restoring a burned pine plantation to include both a long leaf/pond pine and hardwood bottom system, vital habitat types which have nearly vanished from the area. This adds even more overall value to the proposed Mitigation Bank. The comprehensive field studies that accompany this mitigation plan far outweigh the general guidelines suggested by EPA for setting mitigation ratios. Based on numerical methods established by HGM along with the insight gained from regulatory personnel during numerous site visits, the following ratio's are identified for the Mitigation Bank: Mitigation Site Ratio Pocosin 1.5:1 Burned Pine Plantation: Pine Flat 1.5:1 Bottomland Hardwood 3.0:1 ' Big Shakey Swamp 3.0:1 The boundary for the areas compensating for NCDOT projects R-2406 and U-2107 have been identified within the Big Shakey Swamp and pocosin mitigation areas. An agreement between NCDOT and the Corp's set the compensation area for each project. The mitigation acreage provided by NCDOT for the impacts resulting from the referenced projects was not based on the ratios established above. I Mitigation Bank Plan Page 43 1 GSRA Wetlands Miti ation Development The exact size and configuration of the Mitigation Bank can be found in Figures 18 and 19. The MCBCL will establish and maintain an accounting system to document the activity of the Mitigation Bank. Each time an approved debit transaction occurs at the Mitigation Bank, the MCBCL will submit a statement to the MBRT. An annual summary of all activity will also be provided to the MBRT. 1 4.5 RESPONSIBLE SPONSOR The MCBCL will be responsible for assuring the success of the Mitigation Bank. This responsibility is clearly documented in the MOA. The operational life of the Mitigation Bank is the period during which the terms and conditions of the MOA are applicable, and signatories of the MOA are applicable and responsible for carrying out its provisions. The operational life of the Mitigation Bank will terminate at the point when (1) compensatory mitigation credits have been exhausted or the activity is voluntarily terminated with written notice by the sponsor under the terms of the MOA, and (2) it has been determined that the fully debited area is functionally self-sustaining to the degree specified in this Mitigation Plan. It is the intent of MCBCL to develop all of the Pocosin and Big Shakey Swamp mitigation areas upon approval of this plan. The MCBCL intends to restore the burned pine plantation in two phases. This phasing will allow for adjustments to be made, if required, to ensure the restoration measures implemented are as successful as possible. The first phase will contain 110.04 acres (the four most eastern blocks of the mitigation area) and will be developed upon approval of this plan. The remaining area will be developed within three years of plan approval. The Mitigation Bank will be protected to effectively prevent harmful activities that would jeopardize its continued conservation purpose. 1 1 t Mitigation Bank Plan Page 44 A t 1 i 1 1 1 1 1 1 1 1 s i BOUNDARY FOR NCDOT PROJECT R-2406 PT. NORTHING EASTING 2000 292549 .808 2433819 .634 2001 291567 .987 2433941 .040 2002 291197 .054 2434083 .310 2003 289695 .929 2433724 .845 3002 289480 .562 2433926 .601 2004 288743. 248 2434617 .320 2005 1 288726. 774 434732. 654 2065 88432. 073 434639. 491 2066 88417. 141 435319. 180 2060 288582 .772 2435315 .757 3001 289754 .031 2434218 .517 2061 289812 .342 2434163 .891 2062 291224 .637 2434501 .144 2063 291665 .589 2434332 .018 2064 292450 .405 2434234.972 BOUNDARY FOR BIG SHAKEY SWAMP MITIGATION AREA PT. NORTHING EASTING 2000 292549.808 2433819.634 2001 291567.987 2433941.040 2002 291197.054 2434083.310 2003 289695.929 2433724.845 2004 288743.248 2434617.320 2005 288726.774 2434732.654 2006 288378.702 2434628.299 2007 287641.124 2434704.500 2008 287424.734 2434598.432 2009 287049.900 2434600.322 2010 286615.601 2434784.542 2011 286204.234 2434849.008 2012 286148.520 2434739.853 2013 286476.332 2434173.689 2014 286293.821 2433942.624 2015 286114.195 2433969.092 2016 285941.890 2434376.253 2017 285422.932 2433934.594 2018 285182.165 2433577.104 2019 284910.177 2433338.043 2020 284551.347 2433518.800 2021 284948.532 2433910.255 2022 285172.505 2434248.721 2023 285668.890 2434675.829 2024 285786.605 2434908.746 2025 284740.028 2435029.656 2026 283771.233 2435877.297 2027 283222.662 2435860.312 2028 283106.846 2436051.198 2029 283197.988 2436259.568 2030 283336.060 2436269.384 2031 283288.780 2436628.703 2032 283479.851 2436864.165 2033 283674.193 2436948.638 2034 283710.656 2436453.073 2035 284230.631 2436086.441 2036 284468.646 2435843.483 2037 284548.881 2435711.514 2038 284932.355 2435556.227 2039 285199.014 2435377.457 2040 285341.187 2435596.680 2041 285455.964 2435718.036 2042 285671.668 2435761.096 2043 285824.275 2435728.474 2044 285986.012 2435438.786 2045 286712.194 2435194.766 2046 286855.671 2435175.194 2047 286897.409 2435293.943 2048 146 2435404.861 2049 1 286957.409 2435434.871 2050 287094.749 2435411.383 2051 287277.353 2435147.790 2052 287477.418 2435175.194 2053 287680.894 2435596.680 2054 287888.284 2435759.793 2055 288009.586 2435737.608 2056 287709.588 2435413.995 2057 287777.415 2435231.304 2058 288051.713 2435316.128 2059 288222.575 2435339.616 2060 288582.772 2435315.757 2061 289812.342 2434163.891 2062 291224.637 2434501.144 2063 291665.589 2434332.018 2064 292450.405 2434234.972 BOUNDARY FOR NCDOT PROJECT U2107 PT. NORTHING EASTING 2065 288432 .073 2434639. 491 3003 288335 .703 2434626. 572 2006 288378 .702 2434628. 299 2007 287641 .124 2434704 .500 2067 287601 .404 2434678 .336 2068 287439 .194 2435144 .730 2052 287477 .418 2435175. 194 2053 287680 .894 2435596 .680 PT. NORTHING EASTING 2054 287888.284 2435759.793 2055 288009.586 2435737.608 2056 287709.588 2435413.995 2057 287777.415 2435231.304 2058 288051.713 2435316.128 2059 288222.575 2435339.616 '?90 337 ' 1943.1,196 1 H2066 8417.141 28 1 2435319.180 2000 2064 M mcn rno v ao 0) M t 00 -t ,t M N 200 2063 MITIGATION AREA FOR NCDOT PROJECT Z u' R-2406 200 2062 43.00 ACRES / N W +E 2k61 s 2 MITIGATION AREA ?• 206 FOR NCDOT PROJECT 66 02107 004 15.00 ACRES '2059 3058 2055 .2054 20 0 .53 2051 2009 2050 49 48 45 201 2013 '2015 2016 2044 2024 2043 3 2042 017 / ? 2041 2018. 022 &Q2 9 1 7 20 03 6 2035 2034 2033 032 2030 , FIGURE 18. BOUNDARY OF BIG SHAKEY SWAMP NOT TO SCALE Drwrbw., & Davb f 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 f 1 BOUNDARY FOR POCOSIN MITIGATION AREA PT. NORTHING EASTING 4000 301827 .778 2449952 .059 4001 304357 .585 2444629 .363 4002 306725 .470 2445728 .052 4003 308993 .958 2440955 .171 4004 306622 .363 2439864 .275 4005 306081 .607 2441002 .022 4006 303827 .349 2439914 .013 4015 299558 .727 2448895 .171 BOUNDARY FOR BURNED PINE PLANTATION MITIGATION AREA PT. NORTHING EASTING 4007 303175.901 2441011.131 4008 300769.966 2439867.606 4009 299223.299 2443121.737 4010 301629.235 2444265.262 4003 4004 BOUNDARY FOR NCDOT PROJECT R-2406 PT. NORTHING EASTING 4011 302413.557 2442888.616 4012 304663.233 2443986.273 4013 305514.268 2442195.708 4014 303286.221 2441125.576 4016 303002.468 2441722.590 4017 302974.163 2441709.112 BOUNDARY FOR NCDOT PROJECT U2107 PT. NORTHING EASTING 4014 303286.221 2441125.576 4016 303002,468 2441722,590 4017 302974,163 2441709,112 4018 303545.203 440507.641 4019 305162.107 2441286.761 4020 304875.838 2441889.070 4002 4005 POCOSIN MITIGATION AREA 4013 /-MITIGATION AREA 4019 FOR NCDOT PROJECT R-2406 4020 4012 113.00 ACRES 4001 40061 4018 MITIGATION AREAS 40b67 FOR NCDOT PROJECT U2107 4011 28.00 ACRES BURNED PINE PLANTATION 4008 MITIGATION AREA 4009 4010 POCOSIN MITIGATION AREA N W +E S 4015 4000 FIGURE 19. BOUNDARY OF POCOSIN AND BURNED PINE PLANTATION NOT TO SCALE Dsmr! ono & Davis GSRA Wetlands Mitigation Development 5.0 REFERENCES Brinson, M.M. A hydrogeomorphic classification for wetlands. U.S. Army Corps of Engineers, WES, Tech.. Rpt. WRP-DE-4, 79 pp. Bouma, J. 1983. Hydrology and soil genesis of soils with aquic moisture regimes. p. 253-281. In L.P. Wilding et al. (ed.) Pedogenesis and soil taxonomy. I. Concepts and interactions. Elsevier, Amsterdam, Netherlands Cowardin, L.M., V. Carter, F.C. Golet, and E.T. LaRoc. 1979. Classification of wetlands and deepwater habitats of the United States. U.S. Fish and Wildlife Service. OBS, Washington, DC. FWS/OBS 79/31. 103 pp. Daniels, R.B., H.J. Kleiss, S.W. Buol, H.J. Byrd, and J.A. Phillips. 1984. Soil Systems in North Carolina. Bulletin 467, North Carolina Agricultural Research Service, North Carolina State University, Raleigh, NC, 77 p. Dunne T. and L. B. Leopold. 1978. Water in Environmental Planning. W.H. Freeman and Company, NY. Faulkner, S.P., W.H. Patrick, Jr., and R.P. Gambrell. 1989. Field techniques for measuring wetland soil parameters. Soil Sci. Soc.Am. J. 53:883-890. Gambrell, R.P., and W.H. Patrick, Jr. 1978. Chemical and microbiological properties of ' anaerobic soils and sediments. p. 375-423. In Plant life in anaerobic environments. Ann Arbor Sci. Publ. Ann Arbor, MI. Kentula, M.E., R.P. Brooks, S.E. Gwin, C.C. Holland, A.D. Sherman, and J.C. Sifneos. 1992. And approach to improving decision making in wetland restoration and creation. Edited by A.J. Hairston, U.S. Environmental Protection Agency, ' Environmental Research Laboratory, Corvallis OR. 151 pp. McKee, W.H. Jr., 1978. Rust on iron rods indicated depth of soil moisture. Site productivity symposium, U.S. Dept. of Agric, Atlanta, GA 286-291 pp. S.C.S. 1992a. Engineering Field Handbook. U.S.D.A. Soil Conservation Service Publication 210-EFH, i Washington D.C. S.C.S. 1986. Soil Survey Report of Camp Lejeune, NC. USDA Soil Conservation Service, 1984. 1 Mitigation Bank Plan Page 47 r. 1 1 1 1 1 1 P" 1 1 GSRA Wetlands Mitigation Development Veprreaskas, M.J. 1992. Redoximorphic Features for Identifying Aquic Conditions. Tech. Bull. No. 301. NCARA, N.C. State University, Raleigh 33 pp. Wetland Training Institute, Inc. 1991. Field Guide For Wetland Delineation: 1987 Corps of Engineers Manual. WTI 91-2. 133 pp. White, T.A., J.A. Allen, S.F. Mader, D.L. Mengel, D.M. Perison and D.T. Tew (eds.). 1991. MiST: A methodology to classify pre-project mitigation sites and develop performance standards for construction and restoration of forested wetlands. Results an EPA-sponsored workshop. Region IV Wetlands Planning Unit. U.S. Environmental Protection Agency. 85 pp. WU. 1993. Installing monitoring wells/piezometers in wetlands. Waterways Res. Prog. Note HY lA 3.1 14pp. oAgaffey\wetlands\mitbank L fin Mitigation Bank Plan Page 48