MARTIN COUNTY BOARD OF COUNTY COMMISSIONERS

Transcription

1 MARTIN COUNTY BOARD OF COUNTY COMMISSIONERS 2401 S.E. MONTEREY ROAD STUART, FL DOUG SMITH Commissioner, District 1 September 17, 2015 Telephone: (772) Fax: (772) kfitzpat@martin.fl.us ED FIELDING Commissioner, District 2 ANNE SCOTT Commissioner, District 3 SARAH HEARD Commissioner, District 4 Samantha L. Rice Biologist, Project Manager U.S. Army Corps of Engineers 4400 PGA Boulevard, Suite 500 Palm Beach Gardens, Florida JOHN HADDOX Commissioner, District 5 Re: SAJ (Martin County, FL) Bathtub Reef Beach Park & Sailfish Point Beach Nourishment Dear Samantha: TARYN KRYZDA, CPM County Administrator MICHAEL D. DURHAM County Attorney The following comments are offered in response to the correspondence dated 20 July 2015 from the National Marine Fisheries Service, Habitat Conservation Division (NMFS/HCD) to the US Army Corps of Engineers, pursuant to the 18 June 2015 Public Notice of the abovereferenced permit application, with specific reference to Essential Fish Habitat (EFH) Conservation Recommendations. The specific recommendations are included below (in italics), for ease in reference. 1. The permit requires a buffer distance of no less than 100 feet between the Equilibrium Toe of Fill (ETOF) and nearshore hardbottom habitat. TELEPHONE WEB ADDRESS Response: Do not concur. The proposed beach fill as shown in the permit drawings reflects an ETOF that is substantially greater than 100 feet from the landward edge of the nearshore hardbottom along the majority of the project, narrowing to less than 100 feet toward the north end of the project area along northern Bathtub Reef Beach Park (BRBP). Along BRBP, the proposed fill is not greater in scope than that previously proposed and constructed under SAJ as previously reviewed by NMFS. In fact, the seaward extent of the proposed fill and ETOF is substantially less than the sand platform that presently exists along BRBP through natural, ephemeral sand transport processes. The proposed plan, including the limitation of sand placement to above the mean high water line along the northernmost end of the project (where the nearshore hardbottom reef conjoins the shoreline), is of lesser seaward extent than the sand beach that has historically and presently exists adjacent to, and landward of, the 1 of 22 eng2015l424.docx

2 nearshore hardbottom reef. It is not greater than the previously permitted limits of sand placement along the BRBP shoreline. 2. The permit requires implementation of a biological monitoring plan that clearly identifies the biological differences constituting a project impact. The NMFS request an opportunity to comment on the plan before it is considered final. Response: Partially concur. The proposed biological monitoring plan (16 Feb 2015; copy attached) identifies the biological and attendant physical differences constituting a project impact. In such regard, the plan has been accepted by the Florida Department of Environmental Protection as adequate for the purpose. Additional language can be added to describe the interpretation of statistical analyses used to detect significant changes in sediment cover and benthic community abundance/richness. These changes must be directly attributable to an increase in sand cover over hardbottom resulting from the nourishment project using a Before-After Comparison and evaluation of natural variability from the multiple pre-construction sediment surveys. The statistical analyses described in the plan are compliant with the standard data analyses required by the Department s Draft SOP for biological monitoring protocol. The plan describes the hardbottom monitoring that will be conducted before and following each nourishment event authorized under the project permit. The seagrass monitoring only applies to the initial project construction and dredging of Borrow Area A because the project represents a one-time use of Borrow Area A. 3. The permit requires clearly marking the MHWL in the field and having an independent contractor on-site to continuously verify no material is placed waterward of the MHWL in areas where the permitted construction template does not allow such placement. The NMFS request an opportunity to comment on the plan before it is considered final. Response: Partially concur. The Applicants appreciate the point stated by NMFS; however, the requirement that the project be constructed in accordance with the plans (permit drawings) along the MHWL area is not different than any other limiting requirement of the permit. The construction plans will specify and limit the placement and payment of fill to areas above the MHWL where applicable, and there is neither incentive nor reason for the Contractor to exceed such placement. The Payment and As-Built construction drawings of the project shall verify the placement of sand. If deemed appropriate, the Applicants will mark or otherwise indicate the location of the MHWL by a surveyor to elucidate its location 2 of 22 eng2015l424.docx

3 during construction (similar to that which is sometimes undertaken for dune renourishment in other locations), in which such cases verification by an independent contractor is not otherwise required nor necessary for permit compliance. Moreover, with timely approval of the permit application, construction of the project in present conditions shall require no placement along the north end of the project area (i.e., along the MHWL area) because the existing beach meets or exceeds the proposed sand placement template. 4. The permit requires movement of the transport barges be limited to corridors lacking hardbottom and coral habitat and the securing of all tow lines to avoid any contact with hardbottom or coral habitats. Response: Concur. The project is anticipated to be constructed by hydraulic pipeline (cutterhead) dredge, and not with hopper or transport barges. The dredge pipeline will be routed directly between the inlet borrow areas (Flood Shoal Borrow Areas A and C, and the St. Lucie Inlet Navigation Channel and Impoundment Basin) and the beach placement area; i.e., from the inlet to the beach. The dredge pipeline will therefore not cross, nor be placed adjacent to, the existing nearshore hardbottom resources. As such, the EFH recommendation is germane and consistent with the project plan. 5. The permit requires identification of pipeline corridors that avoid impacts to hardbottom habitat and require contractors to monitor the pipeline daily for leakage. Response: Concur. As described above, the project s proposed pipeline corridors will avoid hardbottom habitat. Additionally, the construction Plans & Specifications shall require that the Contractor monitor, and immediately address, any leakage from pipelines that would adversely impact turbidity or aquatic/hardbottom environs. We anticipate this additional information will assist you in addressing the Conservation Recommendations presented by NMFS in response to the project s Public Notice. Meantime, please let me know if you require any further information regarding this matter. Thank you. Sincerely, Kathy Fitzpatrick, P.E. Coastal Engineer, Martin County 3 of 22 eng2015l424.docx

4 Cc: Kevin Bodge, PE (Olsen Associates, Inc.) Cheryl Miller (Coastal Eco-Group, Inc.) E. J. Ewing (Sailfish Point POCCA) Att: Final Biological Monitoring Plan, February of 22 eng2015l424.docx

5 Final Biological Monitoring Plan Bathtub Beach/Sailfish Point Beach Nourishment Project February 16, INTRODUCTION The July 2014 and February 2015 pre-construction surveys of Bathtub Beach wormreef and nearshore hardbottom are to provide ecological and physical data to increase our understanding of the natural variability in the health, condition, spatial extent, and functions of the sabellariid wormreef (Phragmatopoma lapidosa) and nearshore hardbottom at Bathtub Beach. Phragmatopoma lapidosa is a keystone species in the intertidal and shallow subtidal hardbottom habitats at Bathtub Beach, the largest known wormreef in the southeastern United States. Martin County has supported surveys of the Bathtub Beach wormreef since Biological monitoring surveys of the wormreef and nearshore hardbottom were conducted in 2008 (pre-construction), and from 2010 through 2013, two surveys were conducted each year to evaluate the effects of the 2010 beach restoration project and subsequent emergency fill projects on these important nearshore habitats. Project History Since 2007, Bathtub Beach has been characterized by episodic and often catastrophic shoreline changes. The first of several dune breaching events occurred in October/November A total of 3,426 cubic yards (cy) of sand were trucked to Bathtub Beach for dune placement between 2007 and The 2010 Bathtub Beach Nourishment Project was constructed in March-April 2010 to provide a more long-term solution for maintaining a consistent beach along the park shoreline. Approximately 35,000 cubic yards of beach-compatible sand were placed along 1,500 ft of shoreline from approximately 337 ft south of FDEP R Monument R-34 to 128 ft north of R-36 (FDEP Permit No JC). Approximately six months after completion of the 2010 project, a combination of spring tides and persistently strong northeasterly winds caused significant beach fill losses along the restored shoreline. A breach, approximately 100 ft in width, occurred on October 5 and 6, 2010, and the dune crest receded between 15 and 25 ft along the project shoreline. Martin County conducted an emergency truck-haul dune fill project between October 6 and 9, 2010; approximately 4,525 cubic yards (cy) of fill were placed within the original dune template. A second breach occurred in the project area on November 13, 2010, and by November 27, 2010, approximately 3,307 cy of beach-compatible material had been placed to reconstruct the dune within the original project template. Similar to 2010, an extended period of elevated seas led to rapid shoreline losses in October 2011, and the dune breached at the north end of the project area. An emergency truck haul project was constructed between October 10 and November 10, 2011; 7,997 cy of sand were placed above MHW. An additional 800 cy of sand were placed in mid-december 2011 under a separate County emergency order declaration. In response to Hurricane Sandy in late October 2012, Martin County conducted a series of emergency truck-haul fills in November and 1 5 of 22

6 December Approximately 27, 140 cy were placed, followed by an additional 3,065 cy in early The sand source for all emergency dune projects was upland fill from Stewart Mine. Dredged material from maintenance dredging of the Sailfish Point navigational channel was placed on the southern end of Bathtub Beach Park and along the Sailfish Point shoreline in April-May 2011 (FDEP Permit No JN). The permit modification allowed for placement of up to 6,000 cy of material from just south of R-35 to just north of R-36. Objectives of the Proposed Surveys The complexity of nearshore habitats and physical conditions at Bathtub Beach greatly confounds the assessment of potential impacts from beach fill placement. In order to gain a better understanding of the natural variability in wormreef populations, shoreline erosion, and effects of sand movement over these nearshore hardbottom habitats, more intensive in situ sampling of the intertidal and shallow subtidal wormreef is needed. The proposed surveys are based on the monitoring data and recommendations presented in the post-construction monitoring reports for the 2010 Bathtub Beach Restoration Project. The 2010 monitoring program consisted of 4 permanent shore-perpendicular transects that extend 150 m from the nearshore hardbottom edge. Transect 1 is located furthest to the north with Transects 5, 7 and 9 located progressively to the south (Figures 1 and 2). The monitoring data show that the landward 50 m of the transects contain the habitats that are most likely to be affected by beach nourishment, and these habitats are the most biologically significant and exhibit the highest variability due to their close proximity to the shoreline. The 150-m crossshore transects and standard beach nourishment monitoring methods did not capture population changes and health/condition of the intertidal wormreef habitat, and the data collected offshore of the 50-m distance were not useful in interpreting changes in wormrock cover/extent related to fill placement along the shoreline. The surveys for the proposed nourishment project focus on the landward 50-m of the permanent transects with a substantial increase in sample size in the intertidal and shallow nearshore zone. Two surveys will be conducted in 2014/2015: a summer 2014 survey to evaluate the health and condition of the wormreef and nearshore hardbottom benthic community, fish diversity, and nearshore hardbottom edge/wormreef mapping, and a second survey in February 2015 to capture the second peak in wormrock recruitment. The February survey will consist of only nearshore hardbottom edge/wormreef edge mapping, sediment depth/line intercept monitoring, and wormrock quadrats; the benthic community will not be sampled during the February 2015 survey. The following objectives of the 2010 Biological Monitoring Plan will be addressed so that data can be compared to the historic dataset (2002 through 2013): Objective I (community level): To determine whether the nearshore hardbottom community at Bathtub Beach varies with time and sites sampled - Hypothesis 1A: The hardbottom community will be the same for all periods sampled. - Hypothesis 1B: The hardbottom community will be the same at four latitudes (transects) along the hardbottom. 2 6 of 22

7 Objective II (population level): To determine whether the condition and coverage of P. lapidosa at Bathtub Beach varies among seasons and sites sampled - Hypothesis 2A: The percentage of P. lapidosa will be the same for both seasons sampled. - Hypothesis 2B: The percentage of live, vacant, and damaged P. lapidosa will be the same across sites and seasons sampled Objective III: To estimate effects of future beach restoration projects on the baseline hardbottom community - Hypothesis 3A: Over time, and following the proposed beach renourishment project, the wormreef and nearshore hardbottom benthic community dynamics (variability in space and time) will remain within the same general ecological space as identified in the analysis of the baseline dataset. 2.0 METHODS 2.1 Sediment Depth Monitoring Sediment monitoring will include measurements of standing sediment on substrate and benthos at the four permanent 50-m transects. A ruler, graduated in centimeters (0 cm to 40 cm), will be pressed through the sediment until the ruler reaches refusal; sediment depth will be recorded to the nearest centimeter. Sediment accumulation will be assessed with repeated direct measurements at 1-m intervals starting at 0 m and ending at 50 m for a total of 51 samples/transect. A line-intercept method will be utilized to document sand patches and hardbottom exposure; sand patches where sediment depths in excess of 1 cm occur for a minimum distance of 0.5 m along the transect with no emergent biota will be recorded during this survey. Sediment depth at the four permanent transects will be compared spatially during each survey and to the 2010 monitoring program data where direct comparison can be made. 2.2 Video Documentation The purpose of the video surveys is to provide a permanent record of benthic community conditions at the time of the survey. Video transects will be conducted using a Sony HD video camera in an underwater housing unit. A survey tape will be stretched the length of each 50-m transect. Digital video of the benthic community along each transect will be taken at a height of 40 cm and will progress no faster than five (5) m per minute. The video record will include a slate with all pertinent information including project name, transect name and date for reference. A 360 landscape view at the start and end of each transect will be completed. Since the wormreef is typically exposed during low-tide events, video surveys will be planned for high-tide events. The video record will also include landscape and close-up video of benthos. 3 7 of 22

8 2.3 In Situ Quadrat Monitoring The benthic community will be sampled at the four permanent transects using point intercept quadrats. A 0.5 m 2 quadrat will be used to sample 7.5 m 2 along each 50-m transect (15 quadrats per transect) for a total sample area of 30 m 2. In each quadrat, percent cover of substrate and type (bare rock, rhodoliths/rubble, sand) will be recorded. The maximum sand thickness and the maximum physical relief of hardbottom will be measured from the lowest to highest point in the quadrat (both in cm). Within each quadrat, visual estimates of percent cover and genus/species identification will be performed in situ for the following biological groups: macroalgae (overall percent cover and percent cover of individual genera), cyanobacteria, sponges (with a separate assessment of percent cover of encrusting sponges including Cliona spp. and Pione lampa), tunicates, zoanthids, hydroids, sabellariid wormrock (P. lapidosa) with notation of percent live/damaged/dead), octocorals (genus level), and scleractinian corals (species level). Each colony of octocoral and stony coral will be identified, and the maximum height or width will be measured to the nearest cm. The smallest size recorded is 1 cm for individuals less than or equal to 1 cm. Abnormal conditions of each colony will be recorded, e.g., bleaching, disease, and stress. All urchins within quadrats will be identified and counted. Quality assurance/quality control (QA/QC) of the quadrat-based data will be performed by qualified marine biologists trained in the Standard Operating Procedures. Data will be reviewed by the team to ensure consistency in species identification and percent cover assessments. 2.4 Fish Surveys Fish diversity will be assessed during the summer survey by conducting fish counts along the 0 to 20 m segment and 30 to 50 m segment of each transect (intertidal habitat and shallow subtidal). Fish counts will be conducted within 1 m of either side of the transect line during high tide: species, number, and size category of all fish will be recorded (0-10 cm, cm, >25 cm) for comparison to the historic dataset. 2.5 Wormreef Surveys In order to provide a more robust dataset to understand natural variability in the wormreef population and if/how natural variability is affected by beach fill placement, m 2 quadrats will be haphazardly sampled over the entire wormreef in the project area during the July 2014 and February 2015 surveys. GPS coordinates will be recorded at each original quadrat location, and a second quadrat will be sampled at each location by tossing the quadrat at a random heading from the original quadrat. Within each wormrock quadrat, percent cover will be assessed for: 1) live undamaged wormrock (overall percent cover and percent cover of new recruits/juveniles), 2) damaged wormrock 3) dead wormrock/vacant mounds 4 8 of 22

9 2.6 Physical Mapping of Wormreef and Hardbottom Edge The nearshore hardbottom edge between FDEP Range Monuments R-34 and R-36 will be mapped by a scientists during a wading survey using a handheld Trimble XH Differential GPS with decimeter accuracy. Two edges will be mapped: the edge of low-relief exposed hardbottom, typically intermixed with a surface rubble component, and the edge of the live sabellariid wormreef. Mapping of the hardbottom edge will be conducted during preconstruction in July 2014, February 2015, June/July 2015, and immediately prior to project construction in late fall/winter 2015; 4 pre-construction surveys in total. A Hobo temperature logger and Odyssey conductivity/temperature logger were installed at the permanent transects in July These loggers record salinity and temperature hourly. The loggers are retrieved for data download and returned to the field as conditions allow. Laser Survey of Worm Reef Two laser scanning surveys of the emergent wormreef are being conducted to capture the periods of highest biomass/recruitment peaks of P. lapidosa. The first survey was done in July 2014, and the second is planned for February 2015 (postponed from January 2015 due to poor weather conditions during the extreme low tide). These surveys are performed using a Leica ScanStation P20. The survey is conducted at extreme low tide in calm conditions in order to capture the maximum extent of wormreef exposure. The data provide a snapshot of the entire reef at the time of the survey with georeferenced elevation data to provide a 3-D image of the emergent reef. The data will allow the County to track the spatial footprint and elevation of the wormreef in relation to shoreline changes and measure the accretion/erosion of the reef over time. 2.7 Summer 2015 Pre-Construction Survey A second pre-construction survey of the Bathtub Beach project area will be conducted in June/July 2015 according to the methods described above. The second pre-construction survey will include benthic community quadrat sampling, video transects, wormrock quadrats, sediment depth and line intercept sampling, and fish surveys. This pre-construction survey will conducted in conjunction with the comprehensive pre-construction survey of the Sailfish Point project area discussed in Section 3.0. The timing and frequency of the post-construction surveys for the Bathtub Beach/Sailfish Point Beach Nourishment Project are presented in Section SAILFISH POINT PROJECT AREA -BASELINE SURVEY OF NEARSHORE HARDBOTTOM A baseline survey of nearshore hardbottom in the Sailfish Point project area was conducted in September Five permanent cross-shore transects are located at the following locations and extend 150 m east from the landward edge of exposed hardbottom at the time of establishment: R36+300, R37+100, R37+800, R39+400, and R (Figure 3). Because the edge of nearshore hardbottom is located a considerable distance from the shoreline (typically ranging from approximately 80 m to more than 120 m), a cross-shore distance of 150 m was approved by the FDEP prior to transect establishment. Transect locations were selected in consultation with the FDEP. 5 9 of 22

10 Transects were permanently established using a stainless steel long rod (90-cm high) at the 0-m mark along the nearshore hardbottom edge. Stainless-steel short rods (60-cm high) were installed at 5 m, and stainless steel eyebolts (30-cm high) were installed at the 10-m mark and every 10 m to 140 m in areas of exposed hardbottom. A stainless steel long rod was installed at 150 m to denote the end point of each transect. Pins were not installed in sand gaps between hardbottom tracts. Where significant sand gaps occurred, a short rod was placed at the landward and seaward edges of exposed hardbottom. DGPS coordinates were recorded at the start (0 m) and end points (150 m), and at several permanent markers along the transects (Table 2). Hardbottom monitoring protocol followed the methods described in authorized biological monitoring plan for the 2010 Bathtub Beach Restoration Project (FDEP Permit No JC). The nearshore hardbottom edge between R-36 and R-42 was mapped in September 2010, June 2011, and June Two pre-construction hardbottom edge surveys are planned for 2015: one in February 2015 and the second in June/July A third pre-construction hardbottom edge survey will be conducted immediately prior to construction of the proposed Bathtub Beach/Sailfish Point Beach Nourishment Project. Nearshore hardbottom edge mapping methods follow FDEP standard operating procedures; scientific divers tow a taut-line buoy with an attached DGPS antenna, which transmits continuous positions to HYPACK hydrographic survey software on board the survey vessel. During all surveys, the non-towing diver collects video data to document the nearshore hardbottom edge and dominant epibiota and physical habitat conditions. 3.1 Summer 2015 Pre-Construction Survey Sailfish Point Project Area The proposed beach nourishment project extends from R ft. in Bathtub Beach Park to approximately R ft. in Sailfish Point. The project has been designed to avoid long-term impacts from beach fill equilibration; however, the projected equilibrium toe of fill is within 30 m of the nearshore hardbottom edge at R-36, and within 5 to 6 m of the low-relief hardbottom/ rubble edge at R-35. The turbidity mixing zone at the beach fill site during project construction will not extend over nearshore hardbottom; turbidity monitoring will be performed at the edge of exposed hardbottom to minimize potential adverse impacts from elevated turbidity and sedimentation during fill placement. Based on the close proximity of hardbottom resources to the projected equilibrium toe of fill and potential for long-shore fill movement, two additional 150-m permanent transects are proposed: one at R and a second at R The proposed transect locations are shown in Figure 3. Transect locations will be adjusted in the field at the time of establishment to capture the maximum extent of cross-shore hardbottom in these locations. The pre-construction survey of the Sailfish Point project area will be conducted in conjunction with the Bathtub Beach project area survey in June/July Twenty 0.5 m 2 quadrats will be permanent established and sampled along each transect for a total transect sample area of 10 sq. m 2. Quadrats will be distributed along each transect such that at least 2.5 m 2 of area is sampled in the following zones: 0-30 m; m; m; and m. The northeast 6 10 of 22

11 corner of the quadrat will align with a particular meter mark on the transect, and a pin will be installed to mark the location of this meter mark. An additional pin/marker will be installed at the northwest corner of the quadrat. This method will facilitate repeated sampling of the same quadrat in successive surveys. Benthic community, digital video transects, and sediment depth/line intercept monitoring methods are described in Section 2 of this plan; fish surveys will not be conducted at the Sailfish Point transects. Sand patches where sediment depths in excess of 1 cm occur with no emergent biota for a minimum distance of 0.5 m along the transect will be recorded during the line intercept survey. Repeated sediment depth measurements will be conducted every 1 m along the 150-m transects except for larges sand patches and troughs in excess of 0.5 m in width. Sediment depth will be measured at one point, in the middle of the patch, if the patch is 0.5 m to 1.5 meters wide, and at three points if the patch width is over 1.5 m (0.5 m from each edge into the patch and in the middle of the patch. The western and eastern edge of each sand patch/trough will be recorded during the line-intercept survey. 3.2 Pre-Construction Sediment Monitoring Surveys Sailfish Point Project Area Three sediment line intercept and sediment depth surveys will be conducted at the 7 Sailfish Point transects prior to project construction. One survey will be conducted during installation of the additional 2 transects and rehab of the existing 5 transects in May/June 2015, and the second sediment survey will be conducted during the pre-construction benthic survey during the late summer A third sediment depth and line-intercept survey will be conducted immediately prior to project construction in the fall/winter months. 4.0 BATHTUB BEACH/SAILFISH POINT PROJECT AREA- POST CONSTRUCTION SURVEYS Post-construction surveys of the benthic community will be conducted annually during the summer months (May through September) immediately following construction, and 1 year, 2 years, 3 years, and 5 years post-construction. If no impacts are detected during the 3-year postconstruction event, monitoring will be discontinued. The entire Bathtub Beach/Sailfish Point project area shall be monitored during one survey. In addition to the annual comprehensive survey of the benthic community with quadrat assessments, sediment monitoring, and hardbottom edge mapping, two additional sediment depth and line-intercept monitoring events will be conducted annually during the postconstruction survey period for a total of 3 sediment monitoring events/year at the 11 transects in the project area. One survey will be conducted in late spring/early summer; the second survey will be conducted in the late summer/early fall; and the third survey will be conducted in the late fall/winter for comparison to seasonally similar pre-construction surveys. The nearshore hardbottom edge will be mapped twice/year: once during the summer months and once in the fall/winter. 5.0 DATA ANALYSES AND REPORTING A comprehensive pre-construction report of the Bathtub Beach/Sailfish Point project area will be submitted to the FDEP and USACE within 90 days of completion of all pre-construction field 7 11 of 22

12 surveys in Data analyses and interpretation will include comparison of the preconstruction surveys to historic survey data and monitoring data for the 2010 Bathtub Beach Nourishment Project when possible. The FDEP JCP Compliance Officer will be notified at the commencement and completion of each annual post-construction monitoring event. All monitoring data will be submitted to FDEP within 60 days following completion of data collection for the survey year (final sediment monitoring event). This includes a PDF file containing the scanned field datasheets, Excel spreadsheets with quadrat and sediment depth/line intercept data, ArcGIS shapefiles of the hardbottom edge, video transects, and still photo library. Annual post-construction reports will be submitted to the FDEP and USACE within 90 days of survey completion for the year. Annual reports will include a map of hardbottom habitat in the project area with the permanent transects and diver-mapped nearshore hardbottom edge overlaid onto recent aerial photography. Hardbottom exposure and sand cover will be interpreted and delineated in annual aerial photography using ArcGIS. Image enhancement tools in ArcMap will be applied to the aerial photo raster images to aid in manual interpretation of exposed hardbottom. Univariate statistics will be performed using the statistical software package STATISTICA v12. Data will be tested for normality, and if data are not normally distributed, transformations will performed to attempt to normalize the data. If normality assumptions are not satisfied after transformation, the non-parametric equivalent of ANOVA (Kruskal Wallis) or two way repeated measures ANOVA (Friedman) will be used. Standing sediment depth, line intercept, and artificial reef sediment depth, comparisons between survey times are conducted using a repeated measures, paired sample analysis. Multivariate analyses will be performed utilizing PRIMER v6 software (Clarke and Gorley, 2006). Abundance data will be transformed prior to analysis to homogenize variance. Bray-Curtis similarity indices, derived from transformed data, will be used to construct non-metric, multi-dimensional scaling plots. To test for significant differences in benthic community structure between surveys and transects, analyses of similarity (ANOSIM) will be conducted, and similarity percentage analyses (SIMPER) will be used to evaluate specific taxa responsible for differences between clusters of the dominant taxa of 22

13 Table 1. Transect location information for the four permanent transects in the Bathtub Beach Project Area, R-34 to R-36. Transect Eyebolt X Y Latitude (N) Longitude (W) of 22

14 Table 2. Detailed location information for the five permanent cross-shore transects in the Sailfish Point Project Area of 22

15 11 15 of 22

16 R-34 R-35 T 1 T 5 T 7 Meters T 9 R-36 Diver Mapped Nearshore Hardbottom Edges May 2012 June 2013 January 2014 June 2012 Delineated Hardbottom 50 m Transects Bathtub Beach 2012, 2013, and 2014 Hardbottom Edges and 2014 Permanent Transects June 2012 Hardbottom was Delineated Between R Monuments R-34 and R-36 by Coastal Eco-Group Inc. June 2012 Aerial Photography Figure 1 16 of 22

17 R-34 R-35 T 1 T 5 T 7 Meters T 9 R-36 Diver Mapped Nearshore Hardbottom Edges May 2012 June 2013 January 2014 June 2012 Delineated Hardbottom 50 m Transects Bathtub Beach 2012, 2013, and 2014 Hardbottom Edges and 2014 Permanent Transects June 2012 Hardbottom was Delineated Between R Monuments R-34 and R-36 by Coastal Eco-Group Inc. July 2013 Aerial Photography Figure 2 17 of 22

18 R-36 R-37 R-38 R-40 R-41 R Permanent 150 m Transects 2014 Proposed 150 m Transects June 2011 Diver Mapped Hardbottom Edge June 2013 Diver Mapped Hardbottom Edge July 2013 Delineated Hardbottom Edge R Meters Permanent and Proposed Monitoring Transects in the Sailfish Point Project Area July 2013 Aerial Photography Figure 3 18 of 22

19 BATHTUB BEACH/SAILFISH POINT BEACH NOURISHMENT PROJECT FINAL SEAGRASS MONITORING PLAN- FEBRUARY 16, 2015 This plan is designed to evaluate potential impacts to seagrass beds within 150 m (492 ft) of Borrow Area A for the proposed Bathtub Beach/Sailfish Point Beach Nourishment Project. Figure 1 provides the locations of seagrass beds within 150 m of Borrow Area A. The western half of Borrow Area A and the seagrass beds on the flood shoal are located within the Jensen Beach to Jupiter Inlet Aquatic Preserve, Outstanding Florida Waters (Figure 2). A summary of seagrass bed areas within the 150-m turbidity mixing zone is shown in Table 1. Beds 1 and 2 are located more than 150 m from the edge of the borrow area. Bed 5, comprised of patchy to moderate cover of H. johnsonii, is located approximately 100 ft. (30 m) from Borrow Area A and entirely within the 150-m mixing zone. Review of monitoring data from projects at St. Lucie Inlet indicated that ~3.4 NTUs is the maximum difference in natural background variability expected at the flood tidal shoals during a single tide cycle. Turbidity monitoring data from the 2010 dredging of the flood shoal indicate that expected turbidity elevations during dredging are expected to be minimal and should not result in sediment accumulation on seagrass beds. All compliance turbidity readings were < 0.5 NTU higher than background at distance of 150 to 165 m from the dredge. Table 1. Total size of Beds 2 through 5 and seagrass areas within 150-m of Borrow Area A and distance to seagrass bed edge from Borrow Area A. Bed Total Bed Area Area w/in 150-m mixing zone Distance of bed edge to mixing zone 2 9,229 ft 2 (857 m 2 ) ft. (247 m) 3 113,325 ft 2 (10,528 m 2 ) 16,894 ft 2 (1,570 m 2 ) 328 ft. (100 m) 4 27,183 ft 2 (2,525 m 2 ) 25,758 ft 2 (2,393 m 2 ) 230 ft. (70 m) 5 11,672 ft 2 (1,084 m 2 ) 11,672 ft 2 (1,084 m 2 ) 100 ft. (30 m) Total Area 161, 409 ft 2 (14,995 m 2 ) 54,324 ft 2 (5,047 m 2 ) Survey methods Seagrass beds within the turbidity mixing zone are intertidal and dominated by Halophila johnsonii, a dynamic species with a rapid growth rate and high turnover rate. All seagrass beds within 150 m of Borrow Area A (Beds 3, 4 and 5) will be mapped immediately prior to project construction. Bed edge and patch locations will be delineated using a Trimble GeoXH GPS with decimeter accuracy. Although sediment deposition from elevated turbidity is not expected to result in adverse impacts based on the 2010 turbidity monitoring data, seagrass beds within 150- m from Borrow Area A will be evaluated prior to and immediately following dredging to ensure that seagrasses are not adversely impacted by dredging-related sedimentation and turbidity of 22

20 The entire seagrass area within the turbidity mixing zone will be visually assessed during the pre-construction survey for documentation of baseline conditions and overall health. Quantitative transects will be established in Beds 3, 4, and 5 such that a minimum of 1% of the bed areas within the turbidity mixing zone are sampled. Transects will be sampled with 1-m 2 gridded quadrats, subdivided into cm x 10 cm cells; each 10 cm x 10 cm cell will be examined for presence/absence of seagrass by species (i.e. frequency of occurrence). Presence of macroalgae, epiphytes, cyanobacteria/ Lyngbya sp. within each cell will be recorded, and substrate conditions and sedimentation/burial of seagrass shoots will be noted. All quadrats will be photo-documented and georeferenced with GPS coordinates for comparison to the immediate post-construction survey. The immediate post-construction survey will be conducted no later than ten (10) days from completion of dredging in Borrow Area A. Survey methods will be identical to the preconstruction survey. The visual reconnaissance survey of the entire bed areas within the turbidity mixing zone will be repeated to identify any areas of unexpected direct mechanical damage or sedimentation/burial impacts. Turbidity monitoring will be performed at the edge of Seagrass Beds 1 through 5 during dredging of Borrow Area A. If a turbidity reading in excess of 3.4 NTUs above background is recorded at any of these locations during dredging operations, the seagrass beds in the area of the elevated reading shall be visually inspected by marine scientists within 48 hours of the elevated reading. The bed edge at the location of the elevated reading will be mapped using a Trimble GeoXH GPS for comparison to the pre-construction survey, and the quantitative transects/ quadrats will be sampled. If the post-construction survey reveals burial of seagrasses from dredging of Borrow Area A, additional post-construction surveys will be conducted to document recovery of seagrass beds. The duration and extent of post-construction monitoring will depend on the significance of sedimentation/burial impacts recorded during the immediate post-construction survey. A mitigation plan will be developed if permanent and/or long-term impacts are discovered during the post-construction surveys. Reporting An immediate post-construction report shall be submitted to the Department and the U.S. Army Corps of Engineers within 30 days of completion of the immediate post-construction survey. The report shall provide a summary of the pre-construction and post-construction mapping surveys, quantitative quadrat data, and an evaluation of project-related impacts. ArcGIS maps and shape files of seagrass beds will be submitted with electronic copies of all photoquadrats of 22

21 -2 LEGEND Observations of a single to a few rooted shoots of HJ and HW Halophila johnsonii - mean BB cover of 1.6 Continuous mixed bed of HJ and HW - overall mean score BB score of 2.5 Patchy mixed bed of HJ and sparse HW - overall mean BB cover of 0.5 Continuous mixed bed of HW (dominant) and HJ - overall mean BB cover of 2.5 Sparse HW/HJ Patchy HW/HJ Patchy HW/Sparse HJ Continuous HW (dominant) and sparse HJ Continuous HW (dominant) and HJ Continuous HJ (dominant) and HW Continuous SF (dominant) and HW Sparse HJ Dense SF patches and sparse HW Proposed Turbidity Mixing Zone -6 NOTES Reconaissance survey conducted on 6/23/14 Seagrass mapping conducted on 8/6, 8/7, 8/14, 8/20, and 8/21/14 Date of aerial survey: October 2013 Date of inlet bathymetric survey: August 2013 HJ = Halophila johnsonii HW = Halodule wrightii SF = Syringodium filiforme MLW area above -1.5' NAVD 88 Inside Borrow Area A = 61,095.7 sq. ft. / 1.4 ac. Outside Borrow Area A = 237,113.2 sq. ft. / 5.4 ac " = 300' SURVEY AREA LIMITS BED 1-2 BED ' 100.0' A BED 3 BED 4-2 A A ' BED ' ' A2-2 BORROW AREA A -4-4 A3 Bathtub Beach/Sailfish Point Beach Restoration Project Detailed View of Seagrass Beds within Proposed 150-m Turbidity Mixing Zone and Distances to Adjacent Bed Edges DRAWN BY: J. EVERS CHECKED BY: C. MILLER SCALE: 1" = 300' HARDBOTTOM EDGE SURVEY DATE: SEE NOTES JOB NUMBER 8410 FIGURE No of 22

22 ³ Borrow Area A Borrow Area C Legend JensenBeachJupiterInletAqPres Miles Borrow Areas Federal Navigation Channel Figure 2. Location of Borrow Areas A and C within the Jensen Beach to Jupiter Inlet Aquatic Preserve Bathtub Beach/Sailfish Point Beach Nourishment Project Coordinate System: NAD 1983 StatePlane Florida East FIPS 0901 Feet Projection: Transverse Mercator Datum: North American 1983 False Easting: 656, False Northing: Central Meridian: Scale Factor: Latitude Of Origin: Units: Foot US 22 of 22