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HomeMy WebLinkAboutNC0007064_Annual Report_20230327(> DUKE ENERGY APR 2 7 2023 Serial: RA-23-0089 Christopher Johnson, Chief, Water Sciences Section North Carolina Department of Environmental Quality Division of Water Resources 1621 Mail Service Center Raleigh, North Carolina 27699-1621 Subject: Brunswick Steam Electric Plant (BSEP), Unit Nos. 1 and 2 Duke Energy Progress, LLC 2020-2021 Biological Monitoring Report Dear Mr. Johnson: Brunswick Nuclear Plant 8470 River Road SE Southport, NC 28461-8869 Enclosed are three copies of the Brunswick Steam Electric Plant's 2020-2021 Biological Monitoring Report. The report summarizes the results of the monitoring program required by National Pollutant Discharge Elimination System Permit (NPDES) No. NC0007064. Biological monitoring during 2020-2021 reporting period continued to show a reduction in the number of entrained and impinged fish and shellfish resulting from the combination of flow minimization, fine -mesh screens, and the fish diversion structure. The fish return system continued to ensure that large numbers of the most valuable commercial species exhibit the greatest survival and were returned alive to the estuary. The report results indicate that operation of the BSEP continues to have no detectable adverse effect on the populations of fish, shrimp, and crabs residing in estuarine nursery areas. Please contact Mr. Kyle Hussey at (910) 832-3305, or Mr. Drew Petrusic (910) 832- 2728, if there are any questions concerning the data contained in this submittal. Sincerely, Jay Ratliff Plant Manager Brunswick Steam Electric Plant Cc: Kathy Rawls, NCDMF Director Enclosure: BSEP 2020-2021 Biological Monitoring Report (3 copies) ENCLOSURE Brunswick Steam Electric Plant 2020-2021 Biological Monitoring Report Brunswick Steam Electric Plant 2020-2021 Biological Monitoring Report J ` ' ,p Cape Fear River Estuary Water Resources Unit BRUNSWICK STEAM ELECTRIC PLANT 2020-2021 BIOLOGICAL MONITORING REPORT April 2023 Prepared by: DUKE ENERGY PROGRESS, LLC. Environmental Field Support - Water Resources New Hill, North Carolina Brunswick Steam Electric Plant 2020-2021 Biological Monitoring Report Preface This copy of the report is not a controlled document as detailed in the Environmental Science Field Program Quality Assurance Manual. Any changes made to the original of this report subsequent to the date of issuance can be obtained from: Manager Water Resources Duke Energy Progress, Inc. New Hill, North Carolina Duke Energy Progress, LLC i Water Resources Unit Brunswick Steam Electric Plant 2020-2021 Biological Monitoring Report Table of Contents Page Preface................................................................................................................................. i Tableof Contents.................................................................................... ii Listof Tables...................................................................................................................... iii Listof Figures..................................................................................................................... iv Listof Appendices.............................................................................................................. v ExecutiveSummary............................................................................................................ vi 1.0 INTRODUCTION............................................................................................... 1-1 2.0 MONITORING PROGRAM............................................................................... 2-1 2.1 Introduction.......................................................................................................... 2-1 2.2 Methods................................................................................................................ 2-1 2.3 Results and Discussion........................................................................................ 2-3 2.3.1 Water Quality....................................................................................................... 2-3 2.3.2 Dominant Species................................................................................................ 2-3 2.3.3 Seasonality and Abundance................................................................................. 2-4 2.3.4 Survival Estimates............................................................................................... 2-5 2.3.5 Annual Entrainment and Impingement Rate Comparisons ................................. 2-6 2.4 Summary and Conclusions.................................................................................. 2-7 3.0 REFERENCES.................................................................................................... 3-1 4.0 APPENDICES..................................................................................................... A-1 Duke Energy Progress, LLC ii Water Resources Unit Brunswick Steam Electric Plant 2020-2021 Biological Monitoring Report List of Tables Table Page 2.1 Representative species and life stages entrained and impinged at the Brunswick Steam Electric Plant showing spawning location and season ........... 2-9 2.2 Annual mean density and percent of total for the ten most abundant taxa/life stages collected during entrainment sampling at the Brunswick Steam Electric Plant, 2020-2021.................................................................................................. 2-10 2.3 Total number and percent of the ten most abundant taxa/life stages collected during larval impingement sampling at the Brunswick Steam Electric Plan, 2020-2021............................................................................................................ 2-11 2.4 Total number, total weight, and percent of total of the ten most abundant juvenile and adult organisms collected in the Brunswick Steam Electric Plant impingement samples, 2020-2021 ................... 2-12 2.5 Mean densities of selected larval taxa entrained and impinged at the Brunswick Steam Electric Plant, 2020................................................................. 2-13 2.6 Density (no./million m3) and modal length (min) for representative important taxa collected by month with juvenile and adult impingement sampling at the Brunswick Steam Electric Plant, 2021 .............................. 2-15 2.7 Mean percent survival and percent total number of larval organisms collected during larval impingement sampling at the Brunswick Steam Electric Plant, 2020-2021....................................................... 2-16 2.8 Mean percent survival and percent of total number of organisms collected during impingement sampling at the Brunswick Steam Electric Plant, 2020-2021............................................................................................................ 2-17 2.9 Mean annual percent reduction in the number of representative taxa entrained and reductions in impingement mortality at the Brunswick Steam Electric Plant, 1984-2021....................................................... 2-18 Duke Energy Progress, LLC iii Water Resources Unit Brunswick Steam Electric Plant 2020-2021 Biological Monitoring Report List of Figures Figure Page 1.1 Location of the Brunswick Steam Electric Plant near Southport, NorthCarolina..................................................................................................... 1-3 1.2 Location of the fish diversion structure, fish return flume, return basin, and sampling locations at the Brunswick Steam Electric Plant .................................. 1-4 2.1 Mean daily freshwater flow (curs) to the Cape Fear Estuary, 2020-2021......... 2-19 2.2 Annual mean daily freshwater flow to the Cape Fear Estuary, 2000-2021....... 2-19 2.3 Mean monthly intake canal water temperature, 2020-2021 ........................ 2-20 2.4 Mean monthly intake canal salinity, 2020-2021...................................... 2-20 2.5 Annual number of total organisms entrained at the Brunswick Steam Electric Plant and percent reduction from baseline entrainment estimates, 1979-2021............................................................................................................ 2-21 2.6 Annual number of Spot entrained at the Brunswick Steam Electric Plant and percent reduction from baseline entrainment estimates, 1979-2021............................................................................................................ 2-21 2.7 Annual number of Atlantic Menhaden entrained at the Brunswick Steam Electric Plant and percent reduction from baseline entrainment estimates, 1979-2021................................................................................. 2-22 2.8 Annual number of portunid crab megalops entrained at the Brunswick Steam Electric Plant and percent reduction from baseline entrainment estimates, 1979-2021............................................................................................................ 2-22 2.9 Annual number of commercial shrimp postlarvae entrained at the Brunswick Steam Electric Plant and percent reduction from baseline entrainment estimates, 1979-2021................................................................................. 2-23 2.10 Annual number of Atlantic Menhaden impinged at the Brunswick Steam Electric Plant and percent reduction from baseline impingement estimates, 1977-2021............................................................................................................ 2-23 2.11 Annual number of Bay Anchovy impinged at the Brunswick Steam Electric Plant and percent reduction from baseline impingement estimates, 1977-2021................................................................................. 2-24 Duke Energy Progress, LLC iv Water Resources Unit Brunswick Steam Electric Plant 2020-2021 Biological Monitoring Report List of figures (continued) Figure Page 2.12 Annual number of Spot impinged at the Brunswick Steam Electric Plant and percent reduction from baseline impingement estimates, 1977-2021............................................................................................................ 2-24 2.13 Annual number of flounder, Paralichthys spp., impinged at the Brunswick Steam Electric Plant and percent reduction from baseline impingement estimates, 1977-2021..................................................................... 2-25 2.14 Annual number of commercial shrimp (Brown, Pink, and White Shrimp) impinged at the Brunswick Steam Electric Plant and percent reduction from baseline impingement estimates, 1977-2021.............................................. 2-25 2.15 Annual number of blue crabs (all Callinectes spp. combined) impinged at the Brunswick Steam Electric Plant and percent reduction from baseline impingement estimates, 1977-2021..................................................................... 2-26 List of Appendices Appendix Page 1 Summary of historical environmental studies conducted in association with the Brunswick Steam Electric Plant, 1968-2021.......................................... A-1 2 Total number of larval organisms collected during entrainment and larval impingement sampling at the Brunswick Steam Electric Plant, 2020-2021........ A-3 3 Total number and biomass of juvenile and adult organisms collected during impingement sampling at the Brunswick Steam Electric Plant, 2020-2021........ A-7 Duke Energy Progress, LLC v Water Resources Unit Executive Summary Biological monitoring of the Cape Fear River Estuary has been conducted since the early 1960's. Prior to the installation of fine -mesh screens and the fish return system in 1983, data from intensive sampling from the 1970s through the 1990's indicated that operation of the Brunswick Steam Electric Plant had no measurable adverse effect on fish and shellfish populations in the Cape Fear River Estuary. More recent fish and shellfish population studies conducted during 2015 - 2018 indicated no declines in abundance of any species or shifts in species composition in the Cape Fear Estuary that were attributed to station operation. Entrainment and impingement studies through 2021 indicated that the Brunswick Steam Electric Plant intake modifications and operational measures continued to be effective in reducing the number of organisms affected by the withdrawal of cooling water from the Cape Fear Estuary. Evidence supporting this conclusion includes species composition and abundance of organisms entrained and impinged. The species composition and seasonality of organisms collected in the entrainment, larval impingement, and Juvenile/Adult impingement studies through 2021 were similar to previous years and corresponded to the natural seasonality of larval organisms in the Cape Fear Estuary. Anchovies, gobies, Spot, Atlantic Croaker, Atlantic Menhaden, commercial shrimp and crabs were the dominant larvae entrained and impinged. However, use of fine -mesh screens and seasonal flow reductions have reduced the potential risk of entrainment for all larval taxa. This is especially important for organisms that spawn in the near -shore and offshore ocean such as Atlantic Menhaden, Spot, Atlantic Croaker, mullet, flounder, commercial shrimp and crabs. These organisms may potentially be at more risk of being entrained since they are spawned offshore and pass by the plant intake to reach the nursery areas in the Cape Fear Estuary. Conversely, anchovies and gobies are at less risk since they are estuarine residents and spawning occurs throughout the entire estuary. Use of fine -mesh screens and flow reduction, reduced the mean annual numbers of all organisms entrained by 60-96%. Consistently greater annual reductions in entrainment were evident for mullet, flounder, Gobiosoma spp., commercial shrimp and swimming crab larvae. Except for Gobiosoma spp., all are valuable commercial taxa. Larvae that would have been entrained were returned alive by the fish return system to the Cape Fear Estuary in significant numbers. Based on historic survival estimates data, substantial numbers of the larvae tested for survival were returned alive to the estuary. The most valuable commercial taxa, flounder, shrimp and swimming crab larvae, exhibited the greatest survival (> 87%). Considered together, the fish diversion structure and fish return system have substantially reduced the impingement mortality of larger organisms due to cooling water withdrawal. The fish diversion structure excludes many of the larger fish and shellfish from entering the canal. Substantial numbers of fish and shellfish that do get into the intake canal and subsequently become impinged are returned alive to the estuary by the fish return system. Except for Bay Anchovy, reductions in the mean annual impingement mortality of the representative taxa ranged from 92- 99%. Historical fish population monitoring indicated no declines in the abundance of Bay Anchovy as a result of cooling water withdrawal. In addition to a reduction in numbers and mortality, a shift to the impingement of smaller finfish has resulted as well. This shift to smaller individuals is important because the larger individuals that are being excluded (saved) are the reproducing members of the population. In addition, the natural mortality rates of smaller individuals are relatively high compared to that of older, larger individuals so the loss of these earlier life stages results in a smaller loss to the spawning stock biomass. The species composition of organisms collected with impingement sampling also shifted to a greater percentage of shrimp Duke Energy Progress, LLC vi Water Resources Unit and blue crabs rather than larger finfish as a result of the fish diversion structure. This shift in species composition is significant since juvenile and adult shrimp and crabs exhibit excellent survival in the fish return system (> 90%). Results indicate that operation of the Brunswick Steam Electric Plant continues to have no adverse effect on the populations of fish, shrimp, and crabs residing in the Cape Fear Estuary. Station intake and operational modifications including fine -mesh traveling screens, fish return system, fish diversion structure, and seasonal flow minimization continue to be effective in reducing entrainment and impingement mortality after 38 years of operation (1983-2021). Ocean spawned organisms continue to successfully migrate past the station intake canal to populate Walden Creek and the upriver nursery areas. Organisms residing in the estuary are responding to environmental changes and not operation of the Brunswick Steam Electric Plant. Duke Energy Progress, LLC vii Water Resources Unit 1.0 INTRODUCTION Duke Energy Progress, LLC (DEP), formerly Progress Energy Carolinas, Inc. doing business as Carolina Power & Light Company, was issued a National Pollutant Discharge Elimination System (NPDES) permit in December 1974 for operation of the Brunswick Steam Electric Plant (BSEP). The permit allowed for once -through cooling water, withdrawn from the Cape Fear River Estuary (CFE), to be discharged into the Atlantic Ocean (Figure 1.1). A stipulation of the NPDES permit requires biological monitoring to provide sufficient information for a continuing assessment of power plant impacts on the marine and estuarine fisheries of the CFE. Data were reported annually and provide an assessment of the effectiveness of the fish diversion structure, fine -mesh screens, and seasonally based flow minimization in reducing the entrainment and impingement of organisms. Environmental studies associated with the BSEP began in 1968 before the plant began withdrawing cooling water from the estuary. Intensive physical, chemical, and biological studies of the estuary and near -shore ocean were conducted in the mid and late 1970s. These original studies were followed by a long-term monitoring program through the early 1990s aimed at monitoring fish and shellfish populations within the estuary and documenting the effectiveness of the intake modifications at reducing the entrainment and impingement of organisms. A more detailed summary of historical environmental studies can be found in Appendix 1. Intensive assessments throughout the 1970s, before the installation of fine -mesh screens and the fish return system, indicated that cooling -water withdrawal had no measurable adverse effect on fish, shrimp, and crab populations in the CFE (CP&L 1980). Annual entrainment and impingement rates were insignificant compared to the natural mortality rates of the estuary. Annual population levels in the CFE were determined by changing temperature, freshwater flow, and salinity patterns in the estuary (CP&L 1980). A stipulation of the renewed NPDES permit, issued in 1981, and subsequent permits, was the implementation of power station modifications to reduce entrainment and impingement of estuarine fish and shellfish at the cooling water intake structure. A permanent fish diversion structure was constructed across the mouth of the intake canal in November 1982 to reduce impingement by preventing larger fish and shellfish from entering the intake canal (Figure 1.2). In addition, the fish diversion structure has significantly reduced the numbers of threatened and endangered sea turtles entering the intake canal. To reduce the entrainment of larvae, 1-mm fine - mesh screens were installed on two of the four intake traveling -screen assemblies of each unit in July 1983 and on a third assembly per unit in April 1987. At that time, the NPDES permit required that three of the four intake traveling -screen assemblies on each unit be covered with fine -mesh screens. In August 2003, the NPDES permit required two full fine -mesh screens along with two 50% fine -mesh screens on the four intake traveling screens per unit. During January 2012, the NPDES permit required that the existing total number of fine -mesh screens per unit be distributed equally across the four intake traveling screen assemblies. This resulted in - identical traveling screens each having 8 coarse -mesh and 42 fine -mesh screen panels. Intake cooling water traveling screens are operated continuously. Organisms retained on either the fine mesh or coarse mesh traveling screen panels are gently washed into a fiberglass fish return system and are subsequently returned alive to the CFE (Figure 1.2). The fish return system was constructed and became operational during June 1983 and has remained operational since that time. Duke Energy Progress, LLC 1-1 Water Resources Unit Past data indicated that the impingement of large fish and shellfish of the CFE was reduced as a result of the 9.4-mm (3/8-inch) mesh screening on the fish diversion structure (CP&L 1984, 1985a, 1985b). Organisms small enough to enter the intake canal through the fish diversion structure may be impinged on the plant intake screens and returned to the CFE via a fish return flume or they may be entrained through the plant. Similarly, previous studies have documented a reduction in the entrainment of small organisms due to the installation of fine -mesh screens at the intake structure. Larval and juvenile organisms are returned to the CFE via the fish return flume (Hogarth and Nichols 1981; CP&L 1989). Under the current permit, a maximum discharge flow of 1,844 cubic feet per second (cfs) is allowed from December through March and 2,210 cfs is allowed from April through November with the ability to increase discharge to 2,235 cfs during the summer months (Jul -Sep). Seasonal flow minimization during December through March is a measure, in addition to fine -mesh screens, to reduce operational impacts on ocean spawned larvae recruiting to the estuarine nursery areas during that time of year. Beginning in 1994, DEP reduced the biological monitoring program with the concurrence of the North Carolina Department of Environment & Natural Resources. Based on almost two decades of operation with no detectable adverse impact on fish and shellfish populations in the CFE, the monitoring program was modified to concentrate on the impingement and entrainment of organisms. Fish population special studies conducted in the estuarine nursery areas during 2015-2018 indicated no declines in abundance of any target species compared to long-term data collected from the 1980s through 1993 even for Bay Anchovy, a species exhibiting poor survival in the fish return system (DEP 2020). The USEPA published a revised rule to implement §316(b) of the Clean Water Act in the Federal register on August 15, 2014 (USEPA 2014). DEP is moving forward with compliance activities required by the revised §316(b) rule. The purpose of this report is to provide an update of monitoring activities required by the existing NPDES permit. This report presents the 2020- 2021 larval, juvenile, and adult fish and shellfish entrainment and impingement data. Longer term trends (1977-2021) for selected, representative species are included to evaluate the effectiveness of the NPDES-required intake modifications designed to reduce the entrainment and impingement of aquatic organisms. Duke Energy Progress, LLC 1-2 Water Resources Unit r Brunswick Steam Electric Plant NORTH CAROLINA Elizabeth River Ocean Discharge Area �d /ae' creek Diversion Fish Return Structure Plant Site Flume Intake Canal Discharge Weir �l f c acAg � O c' d � Southport • e e O O e � 9 • fj+' N A 0 1 2 3 4 Miles 0 1.5 3 4.5 6 Kilometers Atlantic Ocean Figure 1.1 Location of the Brunswick Steam Electric Plant near Southport, North Carolina. Duke Energy Progress, LLC 1-3 Water Resources Unit EnUainnrertt SanNling Larval Intfrng R 5anpliixj Irrpirtgenierrt Sarryiliiig Discimrge Weir Fish Retrm Flume Fish Rextrn F1mte i F N A Walden Creek eeK C s �a(No Gum Log Branch Fish Return Fish .— Basin Diversion e Structure Intake Canal eti i r F`y � Plant Site Discharge Weir O.A. l� 0 1,250 I i 2,500 5,000 Feet I i I �p,a 0 0 375 750 1,500 Meters Ga� Figure 1.2 Location of fish diversion structure, fish return flume, return basin, and sampling locations at the Brunswick Steam Electric Plant. Duke Energy Progress, LLC 1-4 Water Resources Unit Brunswick Steam Electric Plant 2020-2021 Biological Monitoring Report 2.0 MONITORING PROGRAM 2.1 Introduction Entrainment sampling documented the species composition, seasonality, and abundance of larval and postlarval organisms passing through the cooling system. The larval impingement study evaluated the success of the fine -mesh screens in reducing entrainment of these organisms. Organisms collected with larval impingement sampling were organisms that would have been entrained without the use of fine -mesh screens. Juvenile and adult (J/A) impingement sampling documented species composition, densities, weights, and lengths of juvenile and adult organisms impinged on conventional 9.4-mm (3/8-inch) mesh traveling screens and provided evidence of the continued effectiveness of the fish diversion structure. Survival study results from previous years were presented to provide insight regarding the effectiveness of the return system for returning impinged organisms alive to the CFE (CP&L 1987, 1988). 2.2 Methods Intake canal water temperature and salinity measurements were collected from the fish return flume during impingement sampling. Daily freshwater flow values presented in the report were downloaded from the United States Geological Survey website. Total freshwater input to the CFE was estimated using data from stream gaging stations in the Cape Fear (2105769), Northeast Cape Fear (2108000), and Black Rivers (2106500) according to the methods presented by Giese et al. (1979, 1985). The collection gear used for entrainment and impingement sampling has remained unchanged since 1984 (CP&L 1985a). Entrainment sampling was conducted in the discharge weir (Figure 1.2). Larval impingement and J/A impingement sampling were conducted in the fish return flume. The J/A impingement program included fish and shrimp > 41 turn, portunid crabs > 25 turn, and eels and pipefish > 101 mm. Impinged organisms smaller than these size limits would have been entrained without use of fine -mesh screens and were analyzed with the larval impingement sampling program. These size class cut-off lengths were determined from examination of historic entrainment and impingement length -frequency information. Densities calculated for all larval organisms were averaged to obtain a mean number per 1,000 m3 of water entrained through the plant per sampling date. Densities for J/A organisms impinged on each sampling date were calculated by dividing the total number of organisms collected by the volume of water pumped through the plant. Densities were expressed as the number per million cubic meters of water pumped through the plant during each 24-hour sampling period. Survival in the return system was determined for selected size classes of the dominant organisms that have been impinged at the BSEP in past years (CP&L 1985a, 1986, 1987, 1988). Studies conducted from 1984-1987 were designed to assess survival of larger organisms impinged on the traditional traveling screens and survival of the entrainable size classes of organisms impinged on the 1-mm fine mesh. Weekly survival studies were conducted initially. The frequency of studies was reduced to the major periods of abundance for selected species and size class during the latter two years of studies to target species and size classes where data was lacking. Acute and latent 96-hour survival was assessed. Results of the four -years of survival studies were Duke Energy Progress, LLC 2-1 Water Resources Unit Brunswick Steam Electric Plant 2020-2021 Biological Monitoring Report summarized in the 1987 Biological Monitoring Report (CP&L 1988) and reproduced in section 2.3.4 of this report. An overall assessment of reductions in entrainment due to fine -mesh screens, fish return system, and reductions in plant cooling -water flow was conducted using historical entrainment data collected from 1979 through 2021. However, data collected in 1983 was excluded from the analysis since fine -mesh screens and the fish return system were not fully operational for a portion of that year. Both intake modifications were completed during June 1983. Data prior to 1983 can be used to estimate annual numbers entrained during a period with no controls in place (i.e., no continuously rotating fine -mesh screens or fish return system). Mean daily entrainment densities were multiplied by design cooling water flow and summed to obtain an annual estimate of total number entrained. The design flow of 84.15 cubic meters per second (cros) is the rated flow of all main cooling water pumps per unit. Linear interpolation was used to estimate entrainment rates on non -sampling days. Annual numbers entrained after 1983 were calculated in a similar fashion with the exception that NPDES permitted cooling -water flow (i.e., reduced flow) was used. A calculated annual baseline entrainment rate was obtained by averaging the annual number entrained for the years 1979 through 1982. The estimated annual number entrained each year after 1983 was subtracted from the annual baseline estimate to obtain a percentage reduction from baseline due to the installation of fine -mesh screens, fish return system, and reduced cooling -water flow. A similar process allowed for the calculation of annual numbers impinged for comparison to a calculated baseline annual impingement rate. Two additional years of data, 1977 and 1978, were recovered from historical data sets for inclusion with the long-term comparisons. The period 1977- 1982 represents a period without impingement controls in place (i.e., no fish diversion structure, fish return system, or flow reductions). The calculated baseline impingement rates were obtained by averaging the annual number impinged from 1977-1982 with the exception that data from 1980 and 1981 were not used in the baseline calculation since a temporary fish diversion structure was in place during that time. The estimated annual number impinged each year after 1983 was subtracted from the annual baseline estimate to obtain a percentage reduction from baseline due to the installation of the fish diversion structure, fish return system, and reduced cooling -water flow. Impingement sampling only occurred during the last 6 months of 1983 because construction of the fish return system was in progress earlier that year. Because of this, results of impingement sampling during 1983 are presented but not included in the percentage reduction calculations. The inclusion of survival data allowed for an assessment of reductions in impingement mortality due to the fish diversion structure and the return system together for different species. Ten taxonomic groups were selected for the detailed comparisons of annual numbers entrained and impinged to a calculated baseline as described above (Table 2.1). These taxonomic groups were selected as representative taxa (RT) and life stages based upon 4 main criteria. First, they account for roughly 78% and 66%, respectively, of the larvae and nekton collected in the CFE during the original Cape Fear Studies conducted prior to 1980 (CP&L 1980). In addition, these organisms represent approximately 80% of the larvae and juvenile/adult organisms collected with entrainment and impingement sampling (CP&L 1980, CP&L 1985b, CP&L 1994, DEP 2019). Secondly, these taxonomic groups encompass the spectrum of life history strategies evident within the CFE with respect to spawning location and season. Estuarine dependent species representing both temporary and resident species are included within these taxonomic groups. The third Duke Energy Progress, LLC 2-2 Water Resources Unit Brunswick Steam Electric Plant 2020-2021 Biological Monitoring Report criterion for consideration is that the majority of these taxonomic groups, except for anchovies and gobies, are commercially and recreationally important species. Finally, there is precedent established for the use of these taxonomic groups as RT. Except for the addition of gobies (Gobiosoma spp.), blue crabs, and portunid crab megalops, these were the same taxonomic groups used by the principal investigators during the original Cape Fear Studies during the 1970's (CP&L1980). This is important in that use of these taxonomic groups provides a direct link back to the original studies conducted prior to 1980. The additional two taxa (gobies and portunid crabs) were included beginning in 1980 since relatively large numbers of these taxa may be entrained seasonally. Common names are used throughout the body of the report. The associated scientific names may be found in appendices 2-4. 2.3 Results and Discussion 2.3.1 Water Quality • Freshwater flow to the estuary during 2020-2021 mostly exhibited the typical seasonal patterns of higher freshwater flow during the winter/spring and lower freshwater flow during summer/fall. 2020 experienced two notable exceptions with high flow events in June and November. Heavy rainfall across central North Carolina in June and tropical Storm Eta in November caused flood like conditions in the Cape Fear River basins (Figure 2.1). The mean annual daily freshwater flow was 445 cros for 2020, representing the third highest since 2000, and 317 cros for 2021 (Figure 2.2). • Intake canal salinity ranged between 9 parts per thousand (ppt) and 37 ppt for 2020-2021 (Figure 2.3). Salinity is typically higher in the summer months when freshwater flow to the estuary is lower and decreases in the winter months when freshwater flow to the estuary is greatest. • Mean water temperature of the intake canal and exhibited the typical seasonal pattern of peak cooler temperatures in January/February and peak higher temperatures during July/August (Figure 2.3). The lowest water temperature (9.7°C) was recorded in January 2021 and the highest water temperature (30.7°C) was recorded in July 2020. 2.3.2 Dominant Species • Atlantic croaker, Gobiosoma spp., Anchoa spp., and Spot were the most abundant taxa collected in entrainment samples from both 2020 and 2021 (Table 2.2). Ctenogobious/Gobionellus spp., Penaeidae (postlarvae), and Atlantic Menhaden were also among the ten most numerous taxa entrained during both years. A complete species list showing total number collected can be found in Appendix 2. • Ten taxa (out of a total of 36 taxa) accounted for 97.6% of the total larval organisms collected in larval impingement samples from 2021 (Table 2.3). The most dominant larvae impinged on the fine -mesh screens for both 2020 and 2021 were Atlantic Croaker, Penaeidae (postlarvae), Anchoa spp., and swimming crab megalops. Spot, Gobooma spp., Atlantic Menhaden, and Silver Perch were also among the top ten larval taxa impinged during over both years. Although the relative ranking has varied, the same ten Duke Energy Progress, LLC 2-3 Water Resources Unit Brunswick Steam Electric Plant 2020-2021 Biological Monitoring Report most abundant taxa have generally dominated larval impingement samples each year since 1984. A substantial number of larvae impinged on the fine -mesh screens were returned alive to the CFE (section 2.3.4). A complete species list showing total number collected can be found in Appendix 2. • J/A impingement samples were numerically dominated by Brown Shrimp, White Shrimp, and Bay Anchovy during 2021 (Table 2.4). Additional taxa that were among the top ten collected include Atlantic Croaker, Star Drum, Spot, Threadfin Shad, Atlantic Menhaden, and Blue Crab. Considered together, Bay anchovy, commercial shrimp (Brown, White, and Pink), Atlantic Croaker, and Blue Crab were a significant percentage of the number and biomass impinged on the traveling screens. Prior to installation of the fish diversion structure in 1982, Atlantic Menhaden was consistently the top species collected in terms of number and biomass (CP&L 1980a, 1980b, 1982, 1983). Larger, Age 1+ finfish, such as Spot and Atlantic Croaker also comprised a significant portion of the number and biomass collected with impingement sampling prior to 1983. This shift in species composition after 1983 was a result of the exclusion of larger finfish by the fish diversion structure. This is significant because commercial shrimp and portunid crabs have become the more dominant taxa impinged other than Bay Anchovy. Both shrimp and crabs exhibit relatively high survival in the fish return system. A complete species list showing numbers and weights collected for all species can be found in Appendix 3. 2.3.3 Seasonality and Abundance • Seasonal variations for larvae entrained and impinged in 2020 represent the seasonal patterns expected. Atlantic Menhaden, Spot, Atlantic Croaker, and Pinfish all ocean - spawned species, were most abundant during winter and early spring (Table 2.5). Atlantic Croaker also exhibited a fall recruitment period beginning in September. Estuarine -spawned species (e.g., anchovies, Gobiosoma spp., and silversides) were most abundant during the spring and summer. Seatrout were present during the spring and summer. Portunid crab megalops larvae were collected sporadically throughout the year. • Variation in the daily mean densities per month for larval organisms entrained and impinged were similar to seasonal variations observed in previous years and corresponded to the seasonality of larval fish in the CFE (Table 2.5). This observation is important since it indicates that recruitment to and within the estuary is functioning normally and has not been disrupted by cooling water withdrawal. Changes in peaks of abundance in entrainment and impingement of organisms are within the bounds of previous observations and can be influenced by environmental conditions such as changing freshwater flow to the estuary (Blumberg et al. 2004; Copeland et al. 1979; Lawler et al. 1988; Thompson 1989). • The seasonality of larger individuals collected during 2021 J/A impingement sampling were consistent with data collected from previous years and the natural seasonality reported for these species in the lower CFE by Schwartz et al. (1979). Results indicate that impinged finfish were mostly of young -of -year (YOY) or yearling individuals too small to be excluded by the fish diversion structure. Impingement of significant numbers Duke Energy Progress, LLC 2-4 Water Resources Unit Brunswick Steam Electric Plant 2020-2021 Biological Monitoring Report of larger fish has been virtually eliminated by the installation of the fish diversion structure. Bay Anchovy, collected year-round, was most abundant during the winter when past data indicated that most of the individuals in the population had grown to a size large enough to be impinged on the coarse -mesh traveling screens. Peak densities of brown and pink shrimp occurred during the summer recruitment period. White Shrimp density increased and peaked in August. Blue crabs (Callinectes spp.) were most abundant during summer and fall. • The seasonality for total number of all organisms impinged peaked in June and was driven by the large numbers of Brown Shrimp (Table 2.6). Star Drum, although not displayed on the table were responsible for the other peak in January. Additionally, White and/or Brown Shrimp were the dominant organism impinged for four months out of the year. Commercial shrimp are characterized by high survival rates (>90%) in the fish return system (CP&L 1987, 1988). 2.3.4 Survival Estimates • Seventeen of the impinged larval taxa were previously tested for survival from 1984- 1987 (CP&L 1988). Survival of Pinfish was estimated using data for Atlantic Croaker as a surrogate since Atlantic Croaker and Pinfish both recruit to the estuary during the winter months. These eighteen taxa accounted for approximately 88% of the total number collected with larval impingement sampling during 2020 and 65% during 2021 (Table 2.7). Survival during fast -screen rotation ranged from approximately 1% for anchovies (Anchoa spp. > 13mm) to approximately 96% for pink and white shrimp. Survival adjusted for controls was 100% for commercial shrimp postlarvae, portunid crab megalops, and blue crabs. • Eleven taxa of the dominant J/A organisms impinged were previously tested for survival during fast -screen rotation (Table 2.8; CP&L 1987, 1988). In addition, survival of Star Drum and Silver Perch was estimated using data for two closely related species (Atlantic Croaker and Spot) as surrogates. Data for blue crabs was used as a surrogate for Portunus spp. crabs. These fifteen taxa accounted for approximately 93% of the total number collected with J/A impingement sampling during 2020 and 92% during 2021 (Table 2.8). • Excluding Bay Anchovy, survival ranged from 16% for Atlantic Menhaden to 96% for blue crabs (Table 2.8). Survival adjusted for controls was 100% for commercial shrimp and blue crabs. The most valuable commercial species (shrimp and blue crabs) exhibited the highest survival rates. 2.3.5 Annual Entrainment and Impingement Rate Comparisons • The use of continuously rotating fine -mesh screens, fish return system, and reduced cooling water flow has successfully reduced the number of organisms entrained since 1983. Reductions in the mean annual number of RT entrained compared to a pre-1983 annual baseline entrainment ranged from 60% for spot to 96% for portunid crab megalops (Table 2.9). RT exhibiting relatively high reductions (79-95%) in the annual number Duke Energy Progress, LLC 2-5 Water Resources Unit Brunswick Steam Electric Plant 2020-2021 Biological Monitoring Report entrained compared to a calculated baseline include portunid crab megalops, flounder, mullet, commercial shrimp, Gobiosoma spp., and anchovies. Mean annual reductions in the number of total organisms entrained was relatively high at 71%. Moderate reductions (60-61%) in the annual number entrained were exhibited by Atlantic Croaker, Atlantic Menhaden, seatrout, and Spot. • Variability in the annual number entrained was evident and consistent with the natural variability of larvae within the estuary (Figures 2.5-2.9). Natural variability in recruitment and natural mortality were determined to be significantly greater than entrainment rates and there is no evidence of adverse effects on the annual distribution and abundance of organisms in the CFE due to cooling water withdrawal even prior to intake and operational modifications to reduce entrainment (CP&L 1980). Large-scale fluctuations in the number of larvae entering the estuary are natural and expected due to spawning success, offshore transport mechanisms, and climate conditions (Nelson et al. 1977, Norcross and Austin 1981, Norcross and Shaw 1984). In addition, changing freshwater flow patterns and temperature during recruitment to the CFE has a strong effect on the distribution of larvae within the estuary (Copeland et al. 1979, Lawler et al. 1988, Rogers et al. 1984, Thompson 1989, Weinstein 1979, Weinstein et al. 1979, 1980). Higher freshwater flow during the recruitment season of a species tends to limit dispersal of larvae to the upper estuary and increase the number and availability of larvae potentially entrained with the cooling water withdrawn from the lower estuary. The estimates of annual number entrained compared to baseline estimates have not been normalized for changes in larval recruitment, freshwater flow, or other environmental variables so variability is expected. The mean annual percent reduction values presented in Table 2.9 minimize the annual variability due to changing environmental conditions. Despite the annual variability evident for some taxa, there has been an overall reduction in the annual number of larvae entrained since 1983 for all RT. • Installation of the fish diversion structure, continuously rotating traveling screens, and fish return system has substantially reduced impingement mortality by reducing the numbers of organisms impinged and returning alive large numbers of those organisms that were impinged back to the CFE. Mean annual reductions in impingement mortality of RT since 1984 ranged from 34% for Bay Anchovy to > 99% for Atlantic Menhaden, and blue crabs (Table 2.9). Mean annual reductions in impingement mortality for all other RT was > 90% over 37 years of monitoring. • Consistently large reductions (99%) in the annual number impinged were evident for Atlantic Menhaden (Figure 2.10). A reduction in the annual number of Atlantic Menhaden impinged during 1979, 1980, and 1981 occurred as a result of temporary fish diversion structures installed for those years. A temporary, prototype fish diversion structure was installed and operational only during the period of abundance of Atlantic Menhaden early in 1979. Severe failure of the screens after the first few months in 1979 limited its effectiveness for other species (CP&L 1981). A more substantial prototype structure was in place during 1980 and 1981. • Bay Anchovy has been the numerically dominant species collected within impingement samples since 1984. Small to moderate reductions in the annual number of Bay Anchovy Duke Energy Progress, LLC 2-6 Water Resources Unit Brunswick Steam Electric Plant 2020-2021 Biological Monitoring Report impinged since 1984 were evident for some years and impingement rates were highly variable (Figure 2.11). This was not unexpected since most individuals of this species are small enough to pass through the 9.4-mm mesh screens installed on the fish diversion structure. Bay Anchovy is also characterized by poor survival on the traveling screens so little reduction in impingement mortality was noted for this species. While reductions in the mortality of Bay Anchovy was relatively poor, abundance has not declined over three decades of population monitoring conducted in the CFE (CP&L 1980, 1994, 2002; DEP 2017, 2019, 2020). • Spot and flounder are taxa that provide examples of some variability in the annual number impinged per year (Figures 2.12 & 2.13). When an estimate of survival of the remaining impinged fish is factored in, overall reductions in impingement mortality are greater than 80% per year for most years. • Shrimp and blue crabs exhibited high reductions (94-99%) in annual impingement mortality (Table 2.9). Shrimp are examples of organisms that are not as effectively excluded by the fish diversion structure (Figure 2.14). However, reduction in annual impingement mortality per year was > 90% due to the high survival rates (90-94%) for impinged shrimp. 2.4 Summary and Conclusions Biological monitoring of the CFE has been conducted since the early 1970's. Results of intensive sampling throughout the 1970s and the early 1980's, prior to installation of intake modifications to reduce entrainment and impingement, indicated that power station operations had no measurable adverse effect on fish and shellfish populations in the CFE. Entrainment and impingement studies through 2021 indicated that the BSEP intake modifications and operational measures were effective in reducing the number of organisms affected by the withdrawal of cooling water from the CFE. Evidence supporting this conclusion includes species composition and abundance of organisms entrained and impinged. The species composition and seasonality of organisms collected in the entrainment, larval impingement, and J/A impingement studies through 2021 were similar to previous years and corresponded to the natural seasonality of larval organisms in the CFE. Anchovies, gobies, Spot, Atlantic Croaker, commercial shrimp and crabs were the dominant larvae entrained and impinged. Use of fine -mesh screens has decreased the risk of entrainment for all larval taxa. This is especially important for organisms that spawn in the near -shore and offshore ocean such as Atlantic Menhaden, Spot, Atlantic Croaker, mullet, flounder, shrimp and crabs. These organisms may potentially be at more risk of being entrained since they are spawned offshore and are transported past the intake canal to the nursery areas in the CFE. Conversely, anchovies and gobies are at less risk since they are estuarine residents and spawning occurs throughout the entire estuary. Use of fine -mesh screens and flow reduction over three decades reduced the mean annual numbers of all organisms entrained by 60-96%. Consistently greater reductions in entrainment were evident for mullet, flounder, Gobiosoma spp., shrimp postlarvae and portunid crab megalops. Except for Gobiosoma spp., all are valuable commercial taxa. Larvae that would have been entrained were returned alive by the fish return system to the CFE in significant numbers. Based on historic survival estimates data, Duke Energy Progress, LLC 2-7 Water Resources Unit Brunswick Steam Electric Plant 2020-2021 Biological Monitoring Report substantial numbers of the larvae tested for survival were returned alive to the estuary. The most valuable commercial taxa, flounder, shrimp and swimming crab larvae, exhibited the greatest survival. Considered together, the fish diversion structure and fish return system have substantially reduced the impingement mortality of larger organisms due to cooling water withdrawal. The fish diversion structure excludes many of the larger fish and shellfish from entering the canal. Substantial numbers of fish and shellfish that do get into the intake canal and subsequently become impinged are returned alive to the estuary by the fish return system. Except for Bay Anchovy, reductions in the mean annual impingement mortality of the representative taxa ranged from 90- 99%. Recent and historical fish population monitoring in the CFE indicated no declines in the abundance of Bay Anchovy as a result of cooling water withdrawal. In addition to a reduction in numbers and mortality, a shift to the impingement of smaller finfish has resulted as well. This shift to smaller individuals is important because the larger individuals that are being excluded (saved) by the fish diversion structure are the reproducing members of the population. In addition, the natural mortality rates (predation, weather, tides, etc.) of smaller individuals is relatively high compared to the natural mortality rates of older, larger individuals, so many of the smaller individuals would not survive to maturity even in the absence of power station operation. The species composition of organisms collected with impingement sampling also shifted to a greater percentage of shrimp and blue crabs rather than larger finfish as a result of the fish diversion structure. This shift in species composition is significant since juvenile and adult shrimp and crabs exhibit excellent survival in the fish return system (> 90%). Results indicate that operation of the BSEP continues to have no detectable adverse effect on the populations of fish, shrimp, and crabs residing in the CFE. Station intake and operational modifications including fine -mesh traveling screens, fish return system, fish diversion structure, and seasonal flow minimization continue to be effective in reducing entrainment and impingement mortality after over many decades of operation. Interannual variability in species distribution and abundance is driven by environmental variables with no detectable effect of facility cooling water withdrawal. Duke Energy Progress, LLC 2-8 Water Resources Unit Brunswick Steam Electric Plant 2020-2021 Biological Monitoring Report Table 2.1 Representative species and life stages' entrained and impinged at the Brunswick Steam Electric Plant showing spawning location and season. Entrainment Impingement Spawning location¶ Spawning season§ Anchovies (Anchoa spp.) Bay Anchovy E, NSO SP, SU Atlantic Menhaden Atlantic Menhaden OSO W Spot Spot OSO W Atlantic Croaker Atlantic Croaker OSO W Seatrout (Cynocion spp.) Seatrout E, NSO SP, SU, F Mullet (Mugil spp.) Mullet OSO W Flounder (Paralichthys spp.) Flounder OSO W Gobiosoma spp E SP, SU Shrimp (Litopenaeus spp, Shrimp postlarvae Farfantepenaeus spp.) OSO SP, SU Portunid crab megalops Blue crabs (Callinectes spp) NSO F 'Larval and juvenile life stages are smaller size classes of organisms typically entrained with the cooling water whereas sub adult and adult size classes of organisms are larger organisms impinged on traditional 9.4 mm mesh traveling screens. ¶Spawning location designations are estuarine (E), near -shore ocean (NSO), and offshore ocean (OSO). §Spawning season designations are winter (W), spring (SP), summer (SU), and fall (F). Duke Energy Progress, LLC 2-9 Water Resources Unit Brunswick Steam Electric Plant 2020-2021 Biological Monitoring Report Table 2.2 Annual mean density (no./1000 m3) and percent of total' for the ten most abundant taxa/life stages collected during entrainment sampling at the Brunswick Steam Electric Plant, 2020-2021 (ranking based on 2021 results). 2020 2021 Annual Mean Annual mean Taxon density Percent density Percent Gobisoma spp. 27.2 13.1 33.4 24.2 Anchoa spp. (<13mm) 5.1 2.5 25.5 18.5 Atlantic Croaker 85.3 41.1 19.1 13.9 Anchoa spp. (>13mm) 31.4 15.1 17.8 12.9 Spot 26.2 12.6 10.4 7.5 Commercial ShrimpT postlarvae 7.9 3.8 9.1 6.6 Silversides 1.3 0.6 8.4 6.1 Oenogobius/Gobionellus spp. 2.1 1.0 3.2 2.3 Silver Perch 10.5 5.1 1.9 1.4 Atlantic Menhaden 1.9 0.9 2.0 1.4 Other taxa (n = 26 for 2021) (n = 32 for 2020) 8.6 4.1 8.0 5.8 Total organisms' 207.5 100.0 134.0 100.0 'Total may vary from summation due to rounding of individual taxon. I� Brown, Pink, and White Shrimp. Duke Energy Progress, LLC 2-10 Water Resources Unit Brunswick Steam Electric Plant 2020-2021 Biological Monitoring Report Table 2.3 Total number+ and percents of the ten most abundant taxa/life stages collected during larval impingement sampling at the Brunswick Steam Electric Plant, 2020-2021 (based on ranking for 2021). 2020 2021 Taxon Total number+ Percent Total number' Percent Atlantic Croaker 6,247,504 38.4 5,365,068 37.0 Anchoa spp. (<13mm) 149,968 0.9 3,870,890 26.7 Commercial Shrimp? Postlarvae 4,388,782 27.0 1,854,416 12.8 Spot 1,715,800 10.6 779,108 5.4 Gobisoma spp. 279,541 1.7 721,383 5.0 Swimming Crabs (megalops) 713,796 4.4 527,535 3.6 Anchoa spp. (>:Omm) 414,119 2.5 368,502 2.5 Silver Perch 1,148,515 7.1 362,379 2.5 Gobinellus/Ctenogobious spp. 184,974 1.1 201,739 1.4 Atlantic Menhaden 161,296 1.0 113,830 0.8 Other taxa (n = 36 for 2021) 1,157,945 7.1 347,840 2.4 (n = 39 for 2020) Total8' 16,250,976 100.0 14,512,690 100.0 +Total number is a sum of the twelve sampling -day totals. 'ITotal may vary from summation due to rounding of individual taxon. ? Brown, Pink, and White Shrimp. Duke Energy Progress, LLC 2-11 Water Resources Unit Brunswick Steam Electric Plant 2020-2021 Biological Monitoring Report Table 2.4 Total number, total weight, and percent of total of the ten most abundant juvenile and adult organisms collected in the Brunswick Steam Electric Plant impingement samples, 2020-2021. 2020 Taxon Number' Percent& Weight (kg)' Percent' White Shrimp 61,089 51.1 328.0 57.8 Bay Anchovy 25,514 21.3 31.1 5.5 Brown Shrimp 15,727 13.1 33.9 6.0 Blue Crab 3,111 2.6 81.2 14.3 Pink Shrimp 2,590 2.2 4.7 0.8 Striped Anchovy 1,804 1.5 10.2 1.8 Atlantic Croaker 1,494 1.2 16.9 3.0 Spot 874 0.7 5.9 1.0 Atlantic Menhaden 845 0.7 13.6 2.4 Threadfin Shad 841 0.7 2.0 0.3 Other taxa (n = 73) 5,726 4.8 40.5 7.1 Total 119,616 100.0 568.0 100.0 2021 Taxon Number' Percent& Weight (kg)' Percent' Brown Shrimp 19,371 32.8 69.8 19.5 White Shrimp 14,053 23.8 61.3 17.2 Bay Anchovy 9,031 15.3 11.8 3.3 Atlantic Croaker 3,893 6.6 89.0 24.9 Star Drum 2,719 4.6 7.8 2.2 Spot 2,089 3.5 11.4 3.2 Threadfin Shad 1,505 2.5 6.9 1.9 Atlantic Menhaden 1,407 2.4 37.3 10.4 Blue Crab 900 1.5 21.7 6.1 Lesser Blue Crab 727 1.2 1.9 0.5 Other taxa (n = 63) 3,329 6.0 38.0 11.0 Total 59,024 100.0 357.0 100.0 'Numbers and weights are sums of the twelve sampling day totals. Percentages may not add up to 100 due to rounding. Duke Energy Progress, LLC 2-12 Water Resources Unit Brunswick Steam Electric Plant 2020-2021 Biological Monitoring Report Table 2.5 Mean densities (mean no./1000 m3 per sampling day) of selected larval taxa+ entrained and impinged (1-mm fine mesh) at the Brunswick Steam Electric Plant, 2020. Month Taxa Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Atlantic Menhaden* Larvae entrained 6.7 89 24 15 0 0 0 0 0 0 0 0 Larvae impinged 2.2 14 4.5 15 0 0 0 0 0 0 0 0 Spot* Larvae entrained 96 1,658 122 3.1 0 0 0 0 0 0 0 0 Larvae im in ed 12 335 16 16 0 0 0 0 0 0 0 0 Atlantic Croaker* Larvae entrained 558 3,482 364 474 22 0 0 0 1 3.1 1 140 11,026 72 Larvae impinged 90 624 65 177 8.3 0 0 0 1 1.0 1 5.5 1 406 8.6 Pinfish Larvae entrained 24 86 3.1 0 0 0 0 0 0 0 0 0 Larvae impinged 1.6 37 0.4 0.3 0 0 0 0 0 0 0 0.1 Seatrout* Larvae entrained 0 0 0 0 34 1 12 1 13 1 13 0 0 0 0 Larvae impinged 0 0 0 0 7.3 3.2 1.6 0.2 0 0 0 0 Mullet* Larvae entrained 0 3.1 0 0 0 0 0 0 3.2 0 0 0 Larvae impinged 0 0 0 0.3 0.3 0 0 0 0 0 0 0 Silversides . - � • - � 000��0000000 Anchoa spp. (>_13mm)* Larvae entrained 10 14 11 3.2 134 1,425 38 237 58 50 30 14 Larvae impinged 0.3 7.7 0 0 13 40 0.7 3.3 5.4 1.9 19 1.3 Anchoa s <13mm * Larvae entrained 0 0 0 3 287 20 3.4 53 0 0 0 0 Larvae impinged 0 0 0 1.9 24 6.7 0.5 0.2 0 0 0 0 Gobiosoma s * Larvae entrained 0 0 0 0 1,374 348 91 122 16 9.4 0 0 Larvae impinged 0 0 0 0 49 6.0 2.7 1.7 2.4 0.3 0 0 Duke Energy Progress, LLC 2-13 Water Resources Unit Brunswick Steam Electric Plant 2020-2021 Biological Monitoring Report Table 2.5 (continued) Month Taxa Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Oenogobious/Gobionellus spp. Larvae entrained 0 6.4 3.1 6.1 19 54 3 3.1 3.3 22 10 19 Larvae impinged 0 1.0 0.9 5.4 5.7 5.4 0.7 0.2 0.4 1.0 18 2.6 Shrimp postlarvae* Larvae entrained 41 41 78 32 51 102 6.1 56 44 25 72 19 Larvae impinged 1 47 147 48 93 133 208 29 37 34 24 148 25 Hardback Shrimp Larvae entrained 111 0 0 0 0 0 0 0 6.2 0 Larvae impinged 1 0 1 0 0 0 0.3 0 0.1 0.1 4.8 1.0 Portunid crab megalops* Larvae entrained 0 0 0 21 55 16 6.7 0 6.4 38 10 2.9 Larvae impinged 1.9 0.6 0.2 32 38 49 4.7 0.6 0.3 11 12 7.4 Total all organisms Larvae entrained 739 5,654 608 1 632 2,853 2,003 184 512 143 309 1,175 128 Larvae im pinged 1 159 1,183 176 1 299 474 302 38 48 41 38 511 1 47 Selected taxa comprised > 1% of the total number sampled in either entrainment or larval impingement sampling and/or historically representative important taxa (RT) indicated by an asterisk. Duke Energy Progress, LLC 2-14 Water Resources Unit Brunswick Steam Electric Plant 2020-2021 Biological Monitoring Report Table 2.6 Density (no./million m3) and modal length (mm) for representative important taxa collected by month with juvenile and adult impingement sampling at the Brunswick Steam Electric Plant, 2021. Month Taxa Jan Feb Mar Apr May Jun Jul Aug Sept Oct Nov Dec Atlantic Menhaden densityl 111 1 89 1 12 1 < 1 I < 1 1 2.4 1 2.6 1 2.8 1 2.1 1 0 1 <1 1 0 modallengtN 80 1 105 1 110 1 IN I IN I IN I IN I IN I IN I - I IN I- Spot densityl 56 1 5.5 1 6.6 1 11 1 238 1 38 1 8.4 1 20 1 3.8 1 1.5 1 0 0 modal length 1 80 1 75 1 70 140,50 1 40 1 45 1 60 1 55 190,1101 IN I - - Atlantic Croaker densityl 518 1 70 1 44 1 32 1 5.0 1 72 1 15 1 8.1 1 5.2 1 < 1 1 0 1 0 modal len 110 1 110 1 110 1 55 1 120 1 50 1 80 1 75 1 80 1 IN I - I - Flounder densityl <1 I <1 1 0 1 0 1 0 1 0 1 <1 I <1 I <1 1 0 1 0 0 modal lengtN IN I IN I - I - I - I - I IN I IN I IN I - I - - Seatrout - �®000®000000 - m®aaamaaaaaa White Shrimp densityl 98 1 0 1 4.6 1 3.1 1 1.0 1 3.6 1 168 1 1,366 1 125 1 707 1 43 1 6.0 modallen 80 1 - 180,1201 155 1 IN I IN 1 55 1 75 1 75 1 100 1 70 1 90 Brown Shrimp densityl 0 0 1 0 1 0 1 76 12,754 1 585 1 50 1 33 1 47 1 1.0 < 1 modal lengtN - - I - I - 1 45 1 70 1 85 1 65-70 1 65 1 50 1 IN IN Pink Shrimp densityl 7.3 1 0 1 0 1 0 1 <1 1 0 1 4.2 1 4.8 1 1.1 1 2.3 1 1.9 < 1 modallen IN - - - IN - 50 40 IN IN IN I IN Blue crabs 9.7 5.2 44 12 11 77 41 46 1.4 40 16 6.3 Bay anchovya' 821 180 141 43 382 114 2.2 9.3 0 0 2.9 11 Total organisms 2,424 456 297 121 738 3,163 879 1,639 272 815 70 29 Length -frequency analysis was not conducted on blue crab, and Bay Anchovy data. §IN= insufficient size range collected for determination of modal length. Duke Energy Progress, LLC 2-15 Water Resources Unit Brunswick Steam Electric Plant 2020-2021 Biological Monitoring Report Table 2.7 Mean percent survival' and percent of total number of larval organisms collected during larval impingement sampling at the Brunswick Steam Electric Plant, 2020-2021. Taxa Intake Screens Mean percent survival Adjusted Intake Controls Screens¶ Percent total number 2020 2021 Atlantic Croaker 34 87 39 38.4 37.0 Shrimp postlarvae 90 89 100 27.0 12.8 Spot 29 86 34 10.6 5.4 Portunid megalops 87 86 100 4.4 3.6 Anchoa spp. > 13 0.7 NC 0.7 2.5 2.5 Ctenogobius spp. 15 NC 15 1.1 1.4 Atlantic Menhaden 3.2 39 8.0 1.0 0.8 Flounder spp. 93 97 96 0 0.4 Hardback Shrimp 79 89 89 0.2 0.2 Blue crabs 92 92 100 0.6 0.2 Pinfish§ 34 87 39 1.1 0.2 Mullet 70 92 76 < 0.1 0.1 Weakfish 13 54 24 0.3 0.1 Jacks 36 NC 36 < 0.1 < 0.1 Prionotus spp. 90 97 93 0.1 < 0.1 Planehead Filefish 70 NC 70 < 0.1 < 0.1 Pink and white shrimp 96 93 100 0.3 < 0.1 Percent total number collected 88 65 +Mean present survival values include data collected during 4 years of intake screen survival studies conducted from 1984-1987. Results are presented in CP&L 1987 and 1988 (fast -screen rotation). ¶Survival results were adjusted for control mortality when control results were available. An entry of NC for control data indicates that no control data were collected. Adjusted intake screen survival was estimated by dividing the treatment survival by the control survival to account for competing sources of mortality. The adjusted intake screen survival was truncated to 100 in cases where the calculated value exceeded 100. § The survival percentage for pinfish is an estimate based upon data for a similar species, croaker. Duke Energy Progress, LLC 2-16 Water Resources Unit Brunswick Steam Electric Plant 2020-2021 Biological Monitoring Report Table 2.8 Mean percent survival' and percent total number of organisms collected during impingement sampling at the Brunswick Steam Electric Plant, 2020-2021. Taxa Intake Screens Mean percent survival Adjusted Intake Controls Screens¶ Percent total number 2020 2021 Brown Shrimp 90 80 100 13 33 Shrimp (pink & white) 94 93 100 53 24 Bay Anchovy 4.9 73 6.7 21 15 Atlantic Croaker 45 93 48 1.2 6.6 Star Drum§ 45 93 48 0.2 4.6 Spot 60 98 61 0.7 3.5 Atlantic Menhaden 16 67 24 0.7 2.4 Blue crabs 96 92 100 2.6 1.5 Blackcheek Tonguefish 83 98 85 0.4 0.5 Silver Perch§ 60 98 61 0.1 0.2 Mullet 92 92 100 0.1 0.2 Weakfish 35 54 65 0.1 0.2 Portunus spp. § 96 92 100 0.0 < 0.1 Flounder 71 97 73 < 0.1 < 0.1 Percent total number collected 93 92 + Mean present survival values include data collected during 4 years of intake screen survival studies conducted from 1984-1987. Results are presented in CP&L 1987 and 1988 (fast -screen rotation). ¶ Survival results were adjusted for control mortality. Adjusted intake screen survival was estimated by dividing the treatment survival by the control survival to account for competing sources of mortality. The adjusted intake screen survival was truncated to 100 in cases where the calculated value exceeded 100. § Survival percentages for Portunus spp., star drum, and silver perch are estimates based upon data for similar species (blue crabs, croaker, spot, respectively). Duke Energy Progress, LLC 2-17 Water Resources Unit Brunswick Steam Electric Plant 2020-2021 Biological Monitoring Report Table 2.9 Mean annual percent reduction in the number of representative taxa entrained and reductions in impingement mortality at the Brunswick Steam Electric Plant, 1984-2021+. Entrainment J/A Impingement Percent Percent reduction reduction Anchovies 79 Bay Anchovy 34 Atlantic Menhaden 60 Atlantic Menhaden 99 Spot 61 Spot 96 Atlantic Croaker 60 Atlantic Croaker 92 Seatrout 61 Seatrout 92 Mullet 90 Mullet 98 Flounder 92 Flounder 90 Gobiosoma spp 80 Shrimp postlarvae 82 Shrimp 94 Portunid crab megalops 96 Blue crabs 99 Total organisms 75 'Baseline entrainment and impingement rates for years without reduction controls in place used data from 1979-1982 for entrainment and 1977-1979, and 1982 for impingement. (Impingement data from 1980 and 1981 was exclude from the baseline calculations since a temporary fish diversion structure was in place those years.) Duke Energy Progress, LLC 2-18 Water Resources Unit Brunswick Steam Electric Plant 2020-2021 Biological Monitoring Report Figure 2.2 2,000 1,600 tn E v 1,200 LL- G1 3 800 s a� L 400 0 Figure 2.1 -'0' �Jv pJO 41 OLD �OJ O-'G 2021 2020 Mean daily freshwater flow (cros) to the Cape Fear Estuary, 2020-2021. 500 450 400 £ 350 v 3 300 0 250 L G1 3 200 s 150 L LL 100 50 0 ooa ti °p °p oo' °0 oz% °& °'P °'y titi y3 oti° °y5 °ti6 °y1 °yw °ti9 °y0 oyti ti ti 101 101 1 1 1 1 ti ti tio1°ti ti ti ti ti ti ti ti Annual mean daily freshwater flow to the Cape Fear Estuary, 2000-2021. Duke Energy Progress, LLC 2-19 Water Resources Unit Brunswick Steam Electric Plant 2020-2021 Biological Monitoring Report 35 30 _ 25 V 3 20 i Q 15 E H 10 5 0 Figure 2.3 40 35 30 Q 25 20 N 15 10 5 0 Figure 2.4 00 'SJN NJv "pP "v Oo '04 'Do- t 2020 t 2021 Mean monthly intake canal water temperature (IC) 2020-2021. 4p 1 NJN NJ\, PJc� S�Q OLD �Ov O�c. t 2020 t 2021 Mean monthly intake canal water salinity (ppt) 2020-2021. Duke Energy Progress, LLC 2-20 Water Resources Unit Brunswick Steam Electric Plant 2020-2021 Biological Monitoring Report 9,000 N c 8,000 7,000 E -- 6,000 5,000 4,000 W 3,000 L .8 2,000 E = 1,000 Z 0 MIN f � 100 80 60 40 W 20 y �i 0 ►� 47 47 b RI Ri bJ OJ dl df ✓1 O Q C O Q A A A A A A Number entrained — — Percent reduction Baseline ,7 Figure 2.5 Annual number of total organisms entrained at the Brunswick Steam Electric Plant and percent reduction from baseline entrainment estimates, 1979-2021. 900 800 0 700 E 600 500 '70 400 W 300 200 E 100 Z 0 1�1 ! N I 4%� r t 11 rt � ,� � r t rt I t l tr � M Ir t j 11 d 100 80 C 60 0 40 t� 20 a 0 "Oki c� a-i rn rn �' o 0 0 o a n n r'n. w r! rn a, as rn rn rn as o� o� a Q v v v v Q Q Q v v —� Number entrained - - Percent reduction Baseline Figure 2.6 Annual number of Spot entrained at the Brunswick Steam Electric Plant and percent reduction from baseline entrainment estimates, 1979-2021. Duke Energy Progress, LLC 2-21 Water Resources Unit Brunswick Steam Electric Plant 2020-2021 Biological Monitoring Report N 0 E L W z 160 140 120 100 80 60 40 20 0 100 80 r_ 0 60 j 40 W 20 a 0 rn W ar w w ci o� rn W w °f N N N �V N N N N N N N A A A A A A A A A A A Figure 2.7 Annual number of Atlantic Menhaden entrained at the Brunswick Steam Electric Plant and percent reduction from baseline entrainment estimates, 1979-2021. 1200 D 1000 E 800 oa 600 L W 400 L 200 E 2 0 '9 R] Q7 O} g W Q? W 4 O a O d rl rl+ r1. TM n rw Number entrained — — Percent reduction Baseline 100 80 0 60 40 t� L 0 Figure 2.8 Annual number of portunid crab megalops entrained at the Brunswick Steam Electric Plant and percent reduction from baseline entrainment estimates, 1979-2021. Duke Energy Progress, LLC 2-22 Water Resources Unit Brunswick Steam Electric Plant 2020-2021 Biological Monitoring Report � 600 r_ 500 E .0 400 a 300 L w 200 L 100 E z 0 100 C 80 ❑ 60 40 L 20 0- - �0 —♦ Number entrained Percent reduction Baseline Figure 2.9 Annual number of commercial shrimp postlarve entrained at the Brunswick Steam Electric Plant and percent reduction from baseline entrainment estimates, 1979-2021. 12.0 N 0 ❑ 10.0 �E 8.0 6.0 Cn r_ E 4.0 cD 2.0 a E :3 0.0 z R N R N N N N ry N T T T F T T T T T T T f+ Number impinged — -A — — Percent reduction fish diversion structure Baseline Percent reduction fish diversion structure and return system 100 80 r- 60 :3 a v 40 v sa 20 iZ Figure 2.10 Annual number of Atlantic Menhaden impinged at the Brunswick Steam Electric Plant and percent reduction from baseline impingement estimates, 1977-2021. Duke Energy Progress, LLC 2-23 Water Resources Unit Brunswick Steam Electric Plant 2020-2021 Biological Monitoring Report •-� 10.0 N Q 9.0 8.0 E. 7.0 10 6.0 Ch 5.0 a 4.0 3.0 2.0 1.0 :1 0.0 z a ti ►.°y ci � � � a°io o a', a', � a a o a o a = � � � �' ti Number impinged — -A — — Percent reduction fish diversion structure Baseline —rA Percent reduction fish diversion structure and return system 100 80 C 0 60 a� 40 w C G7 20 L a 0 Figure 2.11 Annual number of Bay Anchovy impinged at the Brunswick Steam Electric Plant and percent reduction from baseline impingement estimates, 1977- 2021. C 0 .0 v� C Q E W M E z 1.6 1.4 1.2 1'0 0.8 0.6 0.4 0.2 0.0 190 r t ! IS ff —� Number impinged — $ — — Percent reduction fish diversion structure Baseline i Percent reduction fish diversion structure and return system 100 80 C 0 ca 60 'o 0 40 C 20 iz 0 Figure 2.12 Annual number of Spot impinged at the Brunswick Steam Electric Plant and percent reduction from baseline impingement estimates, 1977-2021. Duke Energy Progress, LLC 2-24 Water Resources Unit Brunswick Steam Electric Plant 2020-2021 Biological Monitoring Report 0.07 N c 0.0s 0.05 0.04 = 0.03 a E 0.02 a`r 0.01 n 00 100 80 c 60 40 c L 20 d in Z h COm w`" w. ao ; c` ci ate, �i' CID - Number impinged — — — Percent reduction fish diversion structure Baseline Percent reduction fish diversion structure and return system A� rt 4 r t r Figure 2.13 Annual number of flounder, Paralichthys spp., impinged at the Brunswick Steam Electric Plant and percent reduction from baseline impingement estimates, 1977-2021. — 4.0 !r D 3.5 E 3.0 2.5 r 2.0 E 1.5 L 1.0 E 0.5 00 100 80 0 60 40 w L 20 d � 0 !� Cs —0 M h r• 4> >+ �, t+ ey V] 6� r+ m w uo w m os a a �- •• ,- •• •• N m yr rn A a wr w v� m v� °' N N N nor N N N s�v nqr ry nqi l+ A t+ A A A ►+ 7+ A A A —� Humber impinged — — — Percent reduction fish diversion structure Baseline Percent reduction fish diversion structure and return system i dr N M � s 11 rs * it t � rr+ r r + r r s + + r Figure 2.14 Annual number of commercial shrimp impinged at the Brunswick Steam Electric Plant and percent reduction from baseline impingement estimates, 1977-2021. Duke Energy Progress, LLC 2-25 Water Resources Unit Brunswick Steam Electric Plant 2020-2021 Biological Monitoring Report 1.5 N 0 E 1.0 Cn i` 0.5 L E M 0.0 Z d i� 11 � M Number impinged — -A — — Percent reduction fish diversion structure Baseline —A Percent reduction fish diversion structure and return system 100 80 r- 60 40 C C] 20 a 0 Figure 2.15 Annual number of blue crabs (all Callinectes spp. combined) impinged at the Brunswick Steam Electric Plant and percent reduction from baseline impingement estimates, 1977-2021. Duke Energy Progress, LLC 2-26 Water Resources Unit 3.0 REFERENCES Blumberg, A. F., D. J. Dunning, H. Li, D. Heimbugh, and W. R. Geyer. 2004. Use of a particle tracking model for predicting entrainment at power plants on the Hudson River. Estuaries. 27 (3): 515 - 526. CP&L. 1980. Brunswick Steam Electric Plant, Cape Fear Studies Interpretive Report. Carolina Power & Light Company, New Hill, NC. _.1982. Brunswick Steam Electric Plant annual biological monitoring report, 1981. Vol 1. Carolina Power & Light Company, New Hill, NC. .1984. Brunswick Steam Electric Plant annual biological monitoring report, 1983. Carolina Power & Light Company, New Hill, NC. _.1985a. Brunswick Steam Electric Plant annual biological monitoring report, 1984. Carolina Power & Light Company, New Hill, NC. . 1985b. Brunswick Steam Electric Plant Cape Fear Studies, Interpretive Report. Carolina Power & Light Company, New Hill, NC. . 1986. Brunswick Steam Electric Plant annual biological monitoring report, 1985. Carolina Power & Light Company, New Hill, NC. 1987. Brunswick Steam Electric Plant annual biological monitoring report, 1986. Carolina Power & Light Company, New Hill, NC. 1988. Brunswick Steam Electric Plant annual biological monitoring report, 1987. Carolina Power & Light Company, New Hill, NC. 1989. Brunswick Steam Electric Plant annual biological monitoring report, 1988. Carolina Power & Light Company, Southport, NC. 2002. Brunswick Steam Electric Plant annual biological monitoring report, 2001. Carolina Power & Light Company, New Hill, NC. Copeland, B. J., R. G. Hodson, and R. J. Monroe. 1979. Larvae and postlarvae in the Cape Fear Estuary, North Carolina, during operation of the Brunswick Steam Electric Plant, 1974-1978. North Carolina State University, Raleigh, NC. DEP. 2017. Brunswick Steam Electric Plant annual biological monitoring report, 2013-2015. Duke Energy Progress, LLC, New Hill, NC. 2019. Brunswick Steam Electric Plant annual biological monitoring report, 2016. Duke Energy Progress, LLC, New Hill, NC. 2020. Brunswick Steam Electric Plant annual biological monitoring report, 2017-2018. Duke Energy Progress, LLC, New Hill, NC. Duke Energy Progress, LLC 3-1 Water Resources Unit . 2021. Brunswick Steam Electric Plant annual biological monitoring report, 2019. Duke Energy Progress, LLC, New Hill, NC. Giese, G. L., H. B. Wilder, and G. G. Parker, Jr. 1979. Hydrology of major estuaries and sounds of North Carolina. United States Geological Survey. Water resources investigations 79-46. Raleigh, NC. 1985. Hydrology of major estuaries and sounds of North Carolina. United States Geological Survey. Water -supply paper 2221. Alexandria, Va. Hogarth, W. T. and K. L. Nichols. 1981. Brunswick Steam Electric Plant intake modifications to reduce entrainment and impingement losses. Carolina Power & Light Company, New Hill, NC. Lawler, J. P., M. P. Weinstein, H. Y. Chen and T. L. Englert. 1988. Modeling the physical and behavioral mechanisms influencing the recruitment of spot and Atlantic croaker to the Cape Fear Estuary. Am. Fish. Soc. Sym. 3: 115-131. Nelson, W. R., M. C. Ingham, and W. E. Shaaf. 1977. Larval transport and year class strength of Atlantic menhaden, Brevoortia tyrannus. Fish. Bull. U. S. 75: 23-42. Norcross B. L., and H. M. Austin. 1981. Climate scale environmental factors affecting year -class fluctuations of Chesapeake Bay croaker, Micropogonias undulatus. Va. Inst. Mar. Sci. Spec. Sci. Rep. 110: 87 pp. Norcross B. L., and R. F. Shaw. 1984. Oceanic and estuarine transport of fish eggs and larvae: a review. Tran. Am. Fish. Soc. 113: 153-165. Rogers S. E., T. E. Targett, and S. B. Van Sant. 1984. Fish nursery use in Georgia salt -marsh estuaries: The influence of springtime freshwater conditions. Tran. Am. Fish. Soc. 113: 595-606. Schwartz, F. J., P. Perschbacher, L. Davidson, C. Simpson, D. Mason, M. McAdams, K. Sandoy and J. Duncan. 1979. An ecological study of fishes and invertebrate macrofauna utilizing the Cape Fear River Estuary, Carolina Beach Inlet, and adjacent Atlantic Ocean, 1973-1977. BSEP Cape Fear Studies, Volume XIV. Report to Carolina Power & Light Co., Institute of Marine Sciences, University of North Carolina, Morehead City, NC. Thompson, T. E. 1989. Factors limiting the movement of spot, Leiostomus xanthurus, into a freshwater-oligohaline tidal marsh. Master's thesis. Department of Biological Sciences, University of North Carolina at Wilmington, Wilmington, N.C. United States Environmental Protection Agency (USEPA). 2014. National Pollution Discharge Elimination System -Final regulations to establish requirements for cooling water intake structures at existing facilities and amend requirements at phase I facilities; Final rule, 79 Federal Register, pp 48,300 - 48,439. Duke Energy Progress, LLC 3-2 Water Resources Unit Weinstein, M. P. 1979. Shallow marsh habitats as primary nurseries for fishes and shellfishes, Cape fear River, North Carolina. Fish. Bull. 77:339-357. Weinstein, M. P. 1979. Larval retention study, Cape Fear River, 1978. BSEP Cape Fear studies, Volume X. Report to Carolina Power & Light Company. Lawler, Matusky & Skelly Engineers, Pearl River, NY. Weinstein, M. P., S. L. Weiss, R. G. Hodson, and L. R. Gerry. 1979. Retention of three taxa of postlarval fishes in an intensively flushed tidal estuary, Cape Fear River, North Carolina. Fish. Bull. 78(2):419-436. Weinstein, M. P., S. L. Weiss, and M. E. Walters. 1980. Multiple determinants of community structure in shallow marsh habitats, Cape Fear River estuary, North Carolina. Mar. Biol. 58:226-243. Duke Energy Progress, LLC 3-3 Water Resources Unit APPENDICES Appendix 1. Summary of historical environmental studies conducted in association with the Brunswick Steam Electric Plant, 1968-2021. As part of the initial nuclear licensing efforts Carolina Power & Light Company (CP&L, predecessor to Progress Energy Carolinas, Inc and subsequently Duke Energy Progress, LLC) commenced environmental impact studies in 1968. Physical/chemical studies included dye and flow studies, water chemistry, and thermal studies. Biological studies included phytoplankton, zooplankton, benthos and larval fish and shellfish diversity, distribution and abundance studies in the main stem of the estuary. Juvenile and adult fish and shellfish population studies were also conducted in the estuary. Special emphasis was placed on Walden Creek and Snow's Marsh adjacent to the plant's intake canal. Entrainment and impingement studies were also conducted after Unit 2 came online in 1974. In addition, thermal tolerance, swimming performance studies and marsh productivity studies were conducted. Studies were expanded and intensified in 1976 to address the potential adverse impact on the entire estuary by the intake under full 2-unit operation. These comprehensive studies were developed through an interagency review group assembled at CP&L's initiative and included representatives of the EPA, NRC, National Marine Fisheries Service, United States Fish and Wildlife Service, North Carolina Division of Marine Fisheries, North Carolina Division of Environmental Management (predecessor to NC DENR), and CP&L. Exhaustive dye tracer, hydrographic, tidal, temperature, and salinity studies were conducted to model estuarine flow dynamics relative to plant intake flows. Various gear efficiency and sampling methodology studies were conducted to ensure that statistically valid data were collected. The biological studies were modified to provide adequate data concerning the larval, juvenile, and adult fish and shellfish populations having the greatest potential to be adversely affected by plant operation. In addition to weekly entrainment and impingement studies, population studies were conducted in the near -shore ocean, main stem estuary, estuarine shallows, and tidal creek nursery areas from below Southport, NC upstream to the vicinity of Wilmington, NC. Specific criteria studied included species composition plus spatial, seasonal, and inter -annual abundance as well as age, growth, dietary, and tagging studies. The principal investigators from CP&L, NCSU, Institute of Marine Science and Lawler, Matusky and Skelly consultants used results of these studies to determine the mechanisms by which larvae enter and are retained in this intensively flushed estuary and to provide insight regarding the lack of any detectable adverse environmental impact on fish and shellfish populations due to cooling water withdrawal. Results of these studies were compiled in the 20 volume Cape Fear Studies. Beginning in 1980 and continuing through 1993, CP&L conducted a long-term Biological Monitoring Program that would provide for the continued assessment of the impact that the cooling water withdrawal might have on the Cape Fear River Estuary. Using historic biological study results as a guide, particular emphasis was placed on marine fisheries. With some modification, these Biological Monitoring Studies were a continuation of the studies conducted since 1976, thus, allowing for long-term trending of results. Certain studies were also expanded or added to address the effectiveness of the circa 1983 intake modifications in reducing the number of organisms entrained and impinged. Beginning in 1984, a larval impingement study was conducted in addition to the standard entrainment and impingement studies as Duke Energy Progress, LLC A-1 Water Resources Unit Appendix 1. continued. another means to assess the success of fine -mesh screens in reducing entrainment of larvae. Larval fish sampling was conducted in the ship channel and the mouths of two major tidal creek nursery areas. A larval fish discrete depth sampling study was conducted to better understand the distribution of larvae during recruitment to the estuary and to validate the standard larval fish study. A marsh nursery study using trawl, seine, and rotenone sampling was conducted to assess recruitment to and use of the tidal creek nursery areas with special interest placed on Walden Creek adjacent to the Plant's intake canal and several nursery areas upstream of the intake canal. Sampling stations also included a location in the fish return basin. This station along with a special tagging study demonstrated that juvenile fish and shellfish used the return basin as a shallow water nursery area in a fashion similar to the headwaters of a natural tidal creek. A nekton study using trawl and gill net sampling was conducted to assess the populations of juvenile and adult fish and shellfish that could potentially be subject to impingement at the plant intake structure. Sampling stations in the CFE ranged from below Southport, NC to the vicinity of Wilmington, NC. Several sampling stations in the intake canal were used as an additional means of assessing the success of the fish diversion structure in reducing impingement. Survival studies were conducted in the fish return system to assess the success of the return system in returning larval, juvenile, and adult organisms alive to the estuary. A weekly temperature and salinity study was conducted along the main stem of the estuary because historic results indicated that freshwater flow, salinity, and temperature were the main determinants of fish and shellfish distribution and abundance in the estuary. Beginning in 1994 and continuing through the current permit cycle, the biological monitoring program was significantly reduced with the concurrence of State regulatory and resource agencies. Because of almost two decades of data demonstrating that the cooling water withdrawal has no adverse impact to the fish and shellfish populations in the estuary, the monitoring program was reduced to concentrate on entrainment and impingement only. This allowance was based on the fact that if the impingement mortality and entrainment performance remains relatively consistent then the environment remains protected. Sampling frequency was reduced to monthly sampling and results demonstrated the continuing effectiveness of the intake modifications in reducing entrainment and impingement of fish and shellfish. Periodic special study trawl surveys conducted in the marsh/tidal creek nursery areas continued to show no adverse impact on the recruitment to and use of these nursery areas by juvenile fish and shellfish. Duke Energy Progress, LLC believes over three decades of biological and environmental monitoring has resulted in one of the most extensive and informative data bases concerning our nation's estuaries. These data can provide valuable insight regarding the ecology of our nation's estuaries and facilitate compliance with the 2014 existing facility 316(b) regulation. Duke Energy Progress, LLC A-2 Water Resources Unit Appendix 2. Total number+ of larval organisms collected during entrainment (BE) and larval impingement (LI) sampling at the Brunswick Steam Electric Plant, 2020. Scientific name Common name 2020 BE LI Anguillidae Freshwater eels Anguilla rostrate American Eel 0 0 Elopidae Tarpons Elops saurus Ladyfish (lepto.) 6 89 Megalops atlanticus Tarpon (lepto.) 1 3 Ophichthidae Snake eels Myrophis punctatus Speckled Worm Eel 9 254 Myrophis punctatus (lepto.) Speckled Worm Eel (lepto.) 0 40 Ophichthus gomesii Shrimp Eel 1 14 Clupeidae Herrings Brevoortia tyrannus Atlantic Menhaden 43 448 Engraulidae Anchovies Anchoa < 13mm Anchoa < 13mm 117 417 Anchoa> 13mm Anchoa> 13mm 628 1.150 Anchoa mitchilli Bay Anchovy 90 0 Anchoa hepsetus Striped Anchovy 1 0 Belonidae Needlefishes Strongylura manna Atlantic Needlefish 1 0 Exocoetidae Flying fishes Hemiramphus spp. Halfbeaks 1 0 Syngnathidae Pipefishes Syngnathus fuscus Northern Pipefish 2 85 Syngnathus lomsumae Chain Pipefish 0 23 Syngnathus. spp. Pipefish 0 0 Triglidae Searobins Prionotus spp. Searobin 1 32 Prionotustrihulus Bighead Searobin 0 0 Atherinidae Silversides Menidia menidia Atlantic Silverside 0 0 Atherinidae Silversides 30 72 Gerridae Mojarras Gerridae Mor arras 8 36 Eucinostomus argenteus Spotfm Mojarra 0 0 Haemulidae Grunts Orthopristis chrysoptera Piglish 14 176 Sciaenidae Drums Bairdiella chrysoura Silver Perch 238 3,190 Cynoscion nehulosus Spotted Seatrout 6 22 Cynoscion regalis Weakfish 17 132 Menticirrhus spp. Kingfish spp. 1 28 Leiostomus xanthurus Spot 610 4,766 Menticirrhus americanus Southern Kingfish 0 36 Pogonias cromis Black Drum 5 52 Micropogomas undulates Atlantic Croaker 1,939 17,354 Sciaenops ocellatus Red Drum 7 2 Stellifer lanceolatus Star Drum 1 25 Pomatomidae Bluefish Pomatomus saltatrix Bluefish 0 0 Cyprinodontidae Killifishes Fundulus majahs Striped Killifish 1 0 Duke Energy Progress, LLC A-3 Water Resources Unit Appendix 2. continued Scientific name Common name 2020 BE LI Fundulus heteroclitus Mummichog 0 6 Fundulus spp. 0 4 Gobiesocidae Clingfishes Gohiesox strumosus Skilletfish 1 48 Sparidae Porgies Archosargus prohactocephalus Sheepshead 0 4 Lagodon rhomboids Pinfish 36 499 Carangidae Jacks Caranx hippos Crevalle Jack 0 8 Selene vomer Lookdown 0 0 Mugilidae Mullets Mugil cephalus Striped Mullet 1 4 Mugil curema White Mullet 1 4 Blenniidae Combtooth blennies Blennidae Combtooth blennies 6 32 Eleotridae Sleepers Dormitator maculatus Fat Sleeper 0 4 Eleotridae Sleepers I Gobiidae Gobies Gohiosoma spp. 621 777 Microgohius spp. 1 0 Ctenogohius/Gohionellus spp. 47 514 Bothidae Lefteye flounders Citharichthys spp. 3 13 Paralichthys spp. 0 12 Soleidae Soles Trinectes maculatus Hogchoker 1 58 Cyprinidae Minnows Notemigonus crysoleucas Golden Shiner 1 0 Cynoglossidae Tongueflshes Symphurus plagiusa Blackcheek Tonguefish 1 0 Symphurus spp. 5 21 Monacanthidae Fileflsh Stephanolepis hispidus Planehead Filefish 0 5 Poecilliidae Live bearers Gamhusia holihrooki Eastern Mosquitofish 0 12 Diodontidae Porcupine fishes Chilomycterus schoepft Striped Burrfish 0 1 Invertebrates Loliginidae Pencil squids Lilliguncula hrevis Atlantic Brief Squid 0 0 Penaeidae Prawns Commercial shrimp" (postlarve) Shrimp larvae 180 12,305 Trachypenaeus constrictus Hardback Shrimp 3 83 Portunidae Swimming crabs Portunid crab megalops 49 1,983 Portunid crab > l Omm 4 263 Callinectes spp. Blue Crab (> 10mm <20mm) 0 15 Limulidae Horseshoe crabs Limulus polyphemus Atlantic Horseshoe Crab 0 16 'Numbers represent total number collected (per 2-minute LI sample / per 5-minute BE sample) summed over all samples. "Commercial shrimp refer to White, Brown, and Pink Shrimp of genus Farfantepenaeus and Litopenaeus. Duke Energy Progress, LLC A-4 Water Resources Unit Appendix 3. Total number+ of larval organisms collected during entrainment (BE) and larval impingement (LI) sampling at the Brunswick Steam Electric Plant, 2021. Scientific name Common name 2021 BE LI Anguillidae Freshwater eels Anguilla rostrate American Eel 4 16 Elopidae Tarpons Elops saurus Ladyfish (lepto.) 2 18 Megalops atlanticus Tarpon (lepto.) 0 0 Ophichthidae Snake eels Myrophis punctatus Speckled Worm Eel 0 27 Myrophis punctatus (lepto.) Speckled Worm Eel (lepto.) 2 1 Ophichthus gomesii Shrimp Eel 0 4 Clupeidae Herrings Brevoortia tyrannus Atlantic Menhaden 26 316 Alosa spp. Engraulidae Anchovies Anchoa < 13mm Anchoa < 13mm 623 10,752 Anchoa> 13mm Anchoa> 13mm 438 1,024 Anchoa mitchilli Bay Anchovy 0 Anchoa hepsetus Striped Anchovy 0 Belonidae Needlefishes Strongylura manna Atlantic Needlefish 0 0 Syngnathidae Pipefishes Syngnathus fuscus Northern Pipefish 0 8 Syngnathus lomsumae Chain Pipefish 1 44 Syngnathus. spp. Pipefish 0 0 Triglidae Searobins Prionotus spp. Searobin 0 0 Prionotustrihulus Bighead Searobin 0 1 Atherinidae Silversides Menidia menidia Atlantic Silverside 0 0 Atherinidae Silversides 208 36 Gerridae Mojarras Gerridae Mor arras 5 5 Eucinostomus argenteus Spotfm Mojarra 0 0 Haemulidae Grunts Orthopristis chrysoptera Piglish 16 83 Sciaenidae Drums Bairdiella chrysoura Silver Perch 47 1,007 Cynoscion nehulosus Spotted Seatrout 24 8 Cynoscion regalis Weakfish 18 27 Menticirrhus spp. Kingfish spp. 0 1 Leiostomus xanthurus Spot 207 2,164 Menticirrhus americanus Southern Kingfish 0 0 Pogonias cromis Black Drum 4 11 Micropogomas undulates Atlantic Croaker 408 14,903 Sciaenops ocellatus Red Drum 2 5 Stellifer lanceolatus Star Drum 9 5 Pomatomidae Bluefish Pomatomus saltatrix Bluefish 0 0 Cyprinodontidae Killifishes Fundulus majahs Striped Killifish 0 0 Duke Energy Progress, LLC A-5 Water Resources Unit Appendix 3. continued Scientific name Common name 2021 BE LI Ephippidae Spadefishes Chaetodipterus faker Atlantic Spadefish 0 0 Gobiesocidae Clingfishes Gohiesox strumosus Skilletfish 13 29 Sparidae Porgies Archosargus prohactocephalus Sheepshead 1 32 Lagodon rhomboids Pinfish 13 79 Carangidae Jacks Caranx hippos Crevalle Jack 1 0 Selene vomer Lookdown 0 0 Carangidae Jacks 0 1 Mugilidae Mullets Mugil cephalus Striped Mullet 1 0 Blenniidae Combtooth blennies Blennidae Combtooth blennies 17 62 Eleotridae Sleepers Dormitator maculatus Fat Sleeper 1 5 Gobiidae Gobies Gohiosoma spp. 817 2,004 Microgohius spp. 10 4 Ctenogohius/Gohionellus spp. 77 560 Bothidae Lefteye flounders Citharichthys spp. 3 34 Paralichthys spp. 3 161 Soleidae Soles Trinectes maculatus Hogchoker 6 12 Cynoglossidae Tonguefishes Symphurus plagiusa Blackcheek Tonguefish 0 12 Monacanthidae Filefish Stephanolepis hispidus Planehead Filefish 1 5 Stromateidae Butterfish Perprilus spp. 0 1 Synodontidae Lizardfish Synodus foetens Inshore Lizardfish 0 5 Tetraodontidae Pufferfish Sphoeroides maculatus Northern Puffer 0 13 Invertebrates Penaeidae Prawns Commercial shrimp" (postlarve) Shrimp larvae 201 5,151 Farfantepenaeus duorarum Pink Shrimp 0 14 Trachypenaeus constrictus Hardback Shrimp 4 74 Portunidae Swimming crabs Portunid crab megalops 30 1,465 Portunid crab > l Omm 2 95 Callinectes spp. Blue Crab (> 10mm <20mm) 0 3 Limulidae Horseshoe crabs Limulus polyphemus Atlantic Horseshoe Crab 0 26 'Numbers represent total number collected (per 2-minute LI sample / per 5-minute BE sample) summed over all samples. "Commercial shrimp refer to White, Brown, and Pink Shrimp of genus Farfantepenaeus and Litopenaeus. Duke Energy Progress, LLC A-6 Water Resources Unit Appendix 4. Total number+ and biomass (g) of juvenile and adult organisms collected during impingement sampling at the Brunswick Steam Electric Plant, 2022. 2020 Total number Total weight (g) Scientific name Common name Dasyatidae Skates Dasyatis Sabina Atlantic Stingray 4 1,091 Dasyatis say Bluntnose Stingray 0 0 Gymnura micrura Smooth Butterfly Ray 3 326 Anguillidae Freshwater eels Anguilla rostrata American Eel 3 78 Elopidae Tarpons Elops saurus Ladyfish 1 112 Ophichthidae Snake eels Myrophis punctatus Speckled Worm Eel 1 21 Ophichthus gomesii Shrimp Eel 1 210 Clupeidae Herrings Alosa aestivalis Blueback Herring 196 901 Brevoortia tyrannus Atlantic Menhaden 845 13,644 Dorosoma cepedianum Gizzard Shad 312 902 Dorosomapetenense Threadfm Shad 841 1,956 Opisthonema oglinum Atlantic Thread Herring 741 4,352 Rachycentridae Cobia Rachycentron canadum Cobia Engraulidae Anchovies Anchoa hepsetus Striped Anchovy 1,804 10,178 Anchoa mitchilli Bay Anchovy 25,514 31,123 Synodontidae Lizardfishes Synodus foetens Inshore Lizardfishes 12 1,325 Gadidae Codfishes Urophycis jloridana Southern Hake 2 25 Urophycis regia Spotted Hake 265 1,140 Ophidiidae Cusk-eels Ophidion welshi Crested Cusk-Eel 25 166 Ophidion marginatum Striped Cusk-Eel 10 92 Batrachoididae Toadfishes Opsanus tau Oyster Toadfish 14 143 Gobiesocidae Clingfishes Gohiesox strumosus Skilletfish 2 16 Exocoetidae Flying fishes Hemiramphus spp. 33 40 Cyprinodontidae Killifishes Fundulus heteroclitus Mummichog 0 0 Fundulus majahs Striped Killifish 51 161 Atherinidae Silversides Memhras martinica Rough Silverside 191 404 Menidia menidia Atlantic Silverside 9 16 Menidia heryllina Inland Silverside 0 0 Syngnathidae Pipefishes Syngnathus fuscus Northern Pipefish 24 33 Syngnathus louisianae Chain Pipefish 23 38 Gerridae Mojarras Diapterus auratus Irish Pompano 126 1,056 Eucinostomus argenteus Spotfin Mojarra 21 182 Eucinostomus gula Silver Jenny 134 1,357 Duke Energy Progress, LLC A-7 Water Resources Unit Appendix 4. continued 2020 Total number Total weight (g) Scientific name Common name Trighade Searobins Prionotus spp. 0 0 Prionotus evolans Striped Searobin 0 0 Prionotus scitulus Leopard Searobin 5 15 Prionotus trihulus Bighead Searobin 148 626 Prionotus carolinus Northern Searobin 0 0 Pomatomidae Bluefishes Pomatomus saltatrix Bluefish 20 57 Carangidae Jacks Caranx hippos Crevalle Jack 12 452 Caranx latus Horse -Eye Jack 0 0 Selene vomer Lookdown 24 525 Trachinotus carolimrs Florida Pompano 1 21 Belonidae Needlefishes Strongylura manna Atlantic Needlefish 9 18 Lutjanidae Snappers Lutjanus griseur Gray Snapper 45 253 Centrachidae Sunfishes Lepomis macrochirus Bluegill 0 0 Centrarchus macropterus Flier 48 131 Lepomis gulosus Warmouth 67 180 Haemulidae Grunts Orthopristis chrysoptera Pigliish 0 0 Sparidae Porgies Archosargusprohactocephalus Sheepshead 20 418 Lagodon rhomhodies Pinfish 449 5,469 Sciaenidae Drums Baridiella chrysoura Silver Perch 78 300 Cynoscion nehulosus Spotted Seatrout 14 21 Cynoscion regalis Weakfish 237 1,088 Leiostomus xanthurus Spot 874 5,871 Menticirrhus americanus Southern Kingfish 0 0 Menticirrhus littoralis Gulf Kingfish 40 278 Micropogomas undulates Atlantic Croaker 1,494 16,853 Pogonias cromis Black Drum 0 0 Sciaenops ocellatus Red Drum 0 0 Stellifer lanceolatus Star Drum 221 900 Ephippidae Spadefishes Chaetodipterus faker Atlantic Spadefish 4 710 Mugilidae Mullets Mugil cephalus Striped Mullet 11 37 Mugil curema White Mullet 56 93 Blenniidae Combtooth blennies Hypsohlennius hentz Feather Blenny 5 21 Hypsohlennius ionthas Freckled Blenny 31 82 Chasmodes hosquianus Striped Blenny 9 18 Gobiidae Gobies Ctenogohius oceanicus Highfin Goby 47 258 Ctenogohius holesoma Darter Goby 20 60 Duke Energy Progress, LLC A-8 Water Resources Unit Appendix 4. continued 2020 Total number Total weight (g) Scientific name Common name Trichiuridae Snake mackerels Trichiurus lepturus Atlantic Cutlassfish 90 1,195 Stromateidae Butterfishes Pepnlus alepidotus Harvestfish 1 30 Pepnlus tri acanthus Butterfish 109 464 Bothidae Lefleye flounders Ancylopsetta quadrocellata Ocellated flounder 17 143 Citharichthys spilopterus Bay Whiff 47 427 Etropus crossotus Fringed flounder 477 3,056 Paralichthys lethostigma Southern flounder 33 2,035 Scophthalmidae Turbots Scophthalmus aquosus Windowpane Flounder 1 6 Soleidae Soles Trinectes maculatus Hogchoker 33 176 Cynoglossidae Toungeflshes Symphurus plagiusa Blackcheek Toungefish 499 2,446 Balistidae Triggerfishes/Filesfishes Monacanthus hispidus Planehead Filefish 9 36 Tetraodontidae Puffers Chdomycterus schoepfi Striped Burrfish 5 942 Sphoeroides maculates Northern Puffer 6 133 Lagocephalus laevigatus Smooth Puffer 3 21 Scombridae Mackerels Scomheromorus maculatus Spanish Mackerel 0 0 Poecilliidae Live bearers Gamhusia holihrooki Eastern Mosquitofish 16 45 Serranidae Groupers Epinephlus itajara Goliath Grouper 20 119 Invertebrates Loliginidae Pencil squids Lilliguncula hrevis Atlantic Brief Squid 14 41 Limulidae Horseshoes Crabs Limulus polyphenmus Atlantic Horseshoe Crab 0 0 Squillidae Mantis shrimps Squilla empusa Mantis Shrimp 90 1,847 Alpheidae Snapping shrimps Alpheus sp. Snapping Shrimp 0 0 Penaeidae Prawns Farfantepenaeus aztecus Brown Shrimp 15,727 33,885 Farfantepenaeus duorarum Pink Shrimp 2,590 4,734 Luopenaeus setiferus White Shrimp 61,089 328,025 Xiphopeneus sp. Atlantic Seabob 0 0 Trachypeneus constrictus Hardback Shrimp 0 0 Palaemonidae Macrohrachium sp. Portunidae Swimming crabs Callinectes sapidus Blue Crab 3,111 81,245 Callinectes similis Lesser Blue Crab 406 875 Callinectes spp. Swimming crabs 2 7 Portunidae 'Numbers and biomass represent total number and weight collected per 24-hour sample summed over all sample dates. Duke Energy Progress, LLC A-9 Water Resources Unit Appendix 5. Total number+ and biomass (g) of juvenile and adult organisms collected during impingement sampling at the Brunswick Steam Electric Plant, 2021. 2021 Total number Total weight (g) Scientific name Common name Dasyatidae Skates Dasyahs Sabina Atlantic Stingray 14 4,323 Gymnura micrura Smooth Butterfly Ray 2 287 Carcharhinidae Requiem Sharks Rhizoprionodon terraenovae Atlantic Sharpnose Shark 1 182 Ophichthidae Snake eels Myrophis punctatus Speckled Worm Eel 22 344 Ophichthus gomesii Shrimp Eel 10 445 Clupeidae Herrings Alosa aestivalis Blueback Herring 149 743 Alosa pseudoharengus Alewife 1 7 Brevoortia tyrannus Atlantic Menhaden 1,407 37,274 Dorosoma cepedianum Gizzard Shad 9 129 Alosa sapidissima American Shad 68 686 Dorosomapetenense Threadfm Shad 1,505 6,902 Opisthonema oglinum Atlantic Thread Herring 217 2,193 Engraulidae Anchovies Anchoa hepsetus Striped Anchovy 198 699 Anchoa mitchilli Bay Anchovy 9,031 11,840 Synodontidae Lizardfishes Synodus foetens Inshore Lizardfishes 5 379 Gadidae Codfishes Urophycis jloridana Southern Hake 12 44 Urophycis repa Spotted Hake 110 607 Ophidiidae Cusk-eels Ophidion welshi Crested Cusk-Eel 6 42 Batrachoididae Toadfishes Opsanus tau Oyster Toadfish 7 34 Gobiesocidae Clingfishes Gohiesox strumosus Skilletfish 26 96 Umbridae Mudminnows Umbra pygmaea Eastern Mudminnow 5 24 Cyprinodontidae Killifishes Fundulus heteroclitus Mummichog 10 39 Fundulus majahs Striped Killifish 8 10 Atherinidae Silversides Memhras martinica Rough Silverside 252 883 Menidia menidia Atlantic Silverside 8 35 Syngnathidae Pipefishes Syngnathus fuscus Northern Pipefish 18 37 Syngnathus louisianae Chain Pipefish 18 46 Gerridae Mojarras Eucinostomus argenteus Spotfin Mojarra 15 71 Eucinostomus gula Silver Jenny 40 230 Trigliade Searobins Prionotus trihulus Bighead Searobin 30 100 Pomatomidae Bluefishes 15 4,511 Pomatomus saltatrix Bluefish Duke Energy Progress, LLC A-10 Water Resources Unit Appendix 5. continued 2021 Total number Total weight (g) Scientific name Common name Carangidae Jacks Caranx hippos Crevalle Jack 7 409 Belonidae Needlefishes Strongylura manna Atlantic Needlefish 1 98 Lutjanidae Snappers Lutjanus griseur Gray Snapper 4 14 Centrachidae Sunfishes Centrarchus macropterus Flier 11 34 Sparidae Porgies Archosargus prohactocephalus Sheepshead 7 46 Lagodon rhomhodies Pinfish 104 1,100 Sciaenidae Drums Bandiella chrysoura Silver Perch 139 2,574 Cynoscion nehulosus Spotted Seatrout 7 40 Cynoscion regalis Weakfish 49 3,253 Leiostomus xanthurus Spot 2,089 11,371 Menticirrhus americanus Southern Kingfish 12 43 Menticirrhus saxatilis Northern Kingfish 7 21 Micropogomas undulates Atlantic Croaker 3,893 89,046 Pogonias cromis Black Drum 12 689 Stellifer lanceolatus Star Drum 2,719 7,799 Mugilidae Mullets Mugil cephalus Striped Mullet 18 89 Mugil curema White Mullet 30 82 Blenniidae Combtooth blennies Hypsohlennius hentz Feather Blenny 7 35 Hypsohlenniusionthas Freckled Blenny 8 28 Gobffdae Gobies Ctenogohis oceanicus Highfin Goby 20 80 Trichiuridae Snake mackerels Trichiurus lepturus Atlantic Cutlassfish 24 297 Stromateidae Butterfishes Peprilus alepidotus Harvestfish 2 82 Peprilus triacanthus Butterfish 76 953 Bothidae Lefleye flounders Ancylopsetta quadrocellata Ocellated flounder 18 37 Citharichthys spilopterus Bay Whiff 372 3,131 Etropus crossotus Fringed flounder 92 271 Paralichthys lethostigma Southern flounder 17 3,068 Soleidae Soles Trinectes maculatus Hogchoker 33 114 Cynoglossidae Toungefishes Symphurus plagmsa Blackcheek Toungefish 276 868 Tetraodontidae Puffers Chilomycterus schoepfi Striped Burrfish 17 285 Scombridae Mackerels Scomheromorus maculatus Spanish Mackerel 10 10 Duke Energy Progress, LLC A-11 Water Resources Unit Appendix 5. continued 2021 Total number Total weight (g) Scientific name Common name Invertebrates Loliginidae Pencil squids Lilliguncula brevis Atlantic Brief Squid 448 2,314 Squillidae Mantis shrimps Squilla empusa Mantis Shrimp 27 191 Penaeidae Prawns Farfantepenaeus aztecus Brown Shrimp 19,371 69,795 Farfantepenaeus duorarum Pink Shrimp 121 166 Litopenaeus setiferus White Shrimp 14,053 61,277 Trachypeneus constrictus Hardback Shrimp 39 39 Portunidae Swimming crabs Callinectes sapidus Blue Crab 900 21,709 Callinectes similis Lesser Blue Crab 727 1,859 Callinectes spp. Swimming crabs 7 35 'Numbers and biomass represent total number and weight collected per 24-hour sample summed over all sample dates. Duke Energy Progress, LLC A-12 Water Resources Unit