ML031250059
ML031250059 | |
Person / Time | |
---|---|
Site: | Saint Lucie ![]() |
Issue date: | 05/01/2003 |
From: | Jefferson W Florida Power & Light Co |
To: | Document Control Desk, Office of Nuclear Reactor Regulation |
References | |
L-2003-111 | |
Download: ML031250059 (51) | |
Text
Florida Power & Light Company, 6501 S. Ocean Drive, Jensen Beach, FL 34957 FPL May 1, 2003 L-2003-1 11 10 CFR 50.4 U. S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555 Re: St. Lucie Units 1 and 2 Docket Nos. 50-335 and 50-389 2002 Annual Environmental Operating Report In accordance with Section 5.4.1.2 of the St. Lucie Units 1 and 2 Environmental Protection Plans (EPP), enclosed is the Annual Environmental Operating Report for the calendar year 2002.
Positive features of this year's report include: 1) turtle canal mortalities were well within limits of the current biological opinion; 2) the primary barrier net was upgraded in 2002;
- 3) the intake canal was dredged in the area of the turtle barrier nets to reduce current velocities; 4) the plant continues to show no impact on local sea turtle nesting populations; 5) the Taprogee ball loss remains low since the start-up of the system and
- 6) turtle walk information and response to turtle strandings in the area are also summarized in the report.
The turtle net improvements should further limit sea turtle mortalities in the future.
Should there be any questions on this information, please contact George Madden at 772-467-7155.
Vice Preident St. Lucie Plant WJ/GRM Enclosure CLD an FPL Group company
St Lucie Units 1 and 2 Docket Nos. 50-335 and 50-389 L-2003-111 Enclosure FLORIDA POWER & LIGHT COMPANY ST. LUCIE PLANT ANNUAL ENVIRONMENTAL OPERATING REPORT 2002 FLORIDA POWER & LIGHT COMPANY JUNO BEACH, FLORIDA QUANTUM RESOURCES, INC.
PALM BEACH GARDENS, FLORIDA
St. Lucie Units I and 2 Docket Nos. 50-335 and 50-389 L-2003-111 Enclosure ENVIRONMENTAL OPERATING REPORT TABLE OF CONTENTS PART I 1.0 EXECUTIVE
SUMMARY
iii 1.1 Introduction iii 1.2 Turtle Nesting Survey iii 1.3 Intake Canal Monitoring iii 1.4 Other Sea Turtle Protection Activities iv 1.5 Section 7 Consultation and Biological Opinion iv
2.0 INTRODUCTION
1 2.1 Background 1 2.2 Area Description 1 2.3 Plant Description 1 3.0 SEA TURTLE PROGRAM 3 3.1 Introduction 3 3.2 Materials and Methods 5 3.2.1 Nesting Survey 5 3.2.2 Intake Canal Monitoring 5 3.3 Results and Discussion 8 3.3.1 Nesting Survey 8 3.3.1.1 2002 Loggerhead Nesting Summary 8 3.3.1.2 Spatial Distribution of Loggerhead Turtle Nests 8 3.3.1.3 Long-Term Trends in Loggerhead Turtle Nesting 9 3.3.1.4 Seasonal Patterns of Loggerhead Turtle Nesting 10 3.3.1.5 Predation on Loggerhead Turtle Nests 10 3.3.1.6 2002 Green and Leatherback Nesting Summary 11 3.3.1.7 Trends in Green and Leatherback Turtle Nesting 11 3.3.2 Intake Canal Monitoring 12 3.3.2.1 2002 Canal Capture Summary 12 3.3.2.2 Relative Abundance and Temporal Distribution 12 i
St. Lucie Units 1 and 2 Docket Nos. 50-335 and 50-389 L-2003-111 Enclosure 3.3.2.3 Size Class Distributions 13 3.3.2.4 Sex Ratios 13 3.3.2.5 Capture Efficiencies 13 3.3.2.6 Barrier Net Maintenance 14 3.3.2.7 Relative Condition 15 3.3.2.8 Mortalities 16 3.3.2.9 Recapture Incidents 17 3.3.3 Other Sea Turtle Protection Activities 17 3.3.4 Summary 18 4.0 LITERATURE CITED 20 5.0 FIGURES 23 6.0 TABLES 36 PART II
1.0 INTRODUCTION
40 2.0 SEA TURTLE MONITORING AND ASSOCIATED ACTIVITIES 40 3.0 TAPROGGE CONDENSER TUBE CLEANING SYSTEM OPERATION 40 4.0 OTHER ROUTINE REPORTS 41 5.0 TABLES AND FIGURES 42 ii
St. Lucie Units 1 and 2 Docket Nos. 50-335 and 50-389 L-2003-111 Enclosure 1.0 EXECUTIVE
SUMMARY
1.1 INTRODUCTION
The St. Lucie Plant is an electric generating station on Hutchinson Island in St. Lucie County, Florida. The plant consists of two nuclear-fueled 850 net MWe units; Unit 1 was placed on-line in March 1976 and Unit 2 in April 1983. This document has been prepared to satisfy the requirements contained in Appendix B, Environmental Protection Plan (EPP), to St. Lucie Units 1 and 2 Facility Operating Licenses DPR-67 and NPF-16.
This report primarily discusses environmental protection activities related to sea turtles as required by Subsection 4.2 of the EPP. Other routine annual reporting requirements are addressed in Part II.
1.2 TURTLE NESTING SURVEY Since monitoring began in 1971, there have been considerable year-to-year fluctuations in sea turtle nesting activity on Hutchinson Island. However, data collected through 2002 have shown no long-term reductions in nesting on the island and power plant operation has had no significant effect on nesting near the plant. Low nesting activity in 1975 and again in 1981-1983 in the vicinity of the plant was attributed to nighttime construction activities associated with installation of plant intake and discharge structures. Nesting returned to normal or above normal levels following both periods of construction. During 1991, daytime construction activities associated with velocity cap repairs had no apparent effect on nesting. Formal requirements to conduct nesting surveys expired in 1986, but this program has been continued through 1998 with agreement from federal and state agencies. In 1998, the continuation of the nesting survey program, as well as several other sea turtle protection activities, was mandated as part of the biological opinion and incidental take statement issued by the National Marine Fisheries Service (NMFS). An amendment to the Environmental Protection Plan was approved in 1999, which also included this requirement. This requirement remained in place in accordance with the most recent biological opinion issued by NMFS in May 2001.
1.3 INTAKE CANAL MONITORING Since plant operation began in 1976, 8509 sea turtles (including recaptures) representing five different species have been removed from the intake canal. The majority of the turtles captured (57%) were loggerheads. Variation in the number of turtles found during different months and years, including dramatic increases in green turtle captures in recent years, have been attributed primarily to natural variations in the occurrence of turtles in the vicinity of the plant, rather than to operational influences of the plant itself. The majority of turtles removed from the intake canal (about 97%) were captured alive and released back into the ocean. Ongoing evaluations and improvements to the canal capture program have substantially reduced mortalities of entrapped sea turtles during recent years. Turtles confined between the barrier net and ill
St. Lucie Units I and 2 Docket Nos. 50-335 and 50-389 L-2003-111 Enclosure intake headwalls typically reside in the canal for a relatively short period prior to capture, and most are in good to excellent condition when caught. However, in recent years, fresh scrapes have been observed on over 50 percent of the sea turtles captured at the intake canal. These scrapes are likely due to biofouling inside the intake pipe and occur during transport into the canal system.
A 5-inch mesh barrier net completed in January 1996 substantially reduced sea turtle residence times in the intake canal. However, during major influxes of seaweed and jellyfish this net experienced design failure and caused mortalities. To prevent this problem, FPL constructed a new improved barrier net with additional structural support.
Construction of this net was completed in November 2002. The improved design and net material should withstand the seaweed and jellyfish events that caused previous design failure of the old barrier net. Additionally, dredging of the intake canal (completed in 2002) has reduced current velocities around the new barrier net. These actions should significantly reduce the potential for sea turtle mortalities in the plant's intake canal.
In correspondence relevant to the Incidental Take Statement of the May 2001 Biological Opinion there is language that turtle injury or mortality in the canal shall be counted when "resulting from plant operation." In response to this requirement, a qualified veterinarian is utilized to determine cause of death or injury in cases that are not readily apparent.
1.4 OTHER SEA TURTLE PROTECTION ACTIVITIES As participants in the Sea Turtle Stranding and Salvage Network (STSSN), Quantum Resources biologists routinely respond to sea turtle strandings in St. Lucie and Martin Counties. During 2002, biologists responded to 10 sea turtle strandings. All stranding reports were sent to Florida Fish and Wildlife Conservation Commission (FFWCC).
In addition, FPL conducted 17 public service turtle walks during the 2002 nesting season. This program allowed 609 members of the public to be exposed to relevant sea turtle protection issues and, in most cases, to actually view a nesting loggerhead sea turtle.
1.5 SECTION 7 CONSULTATION AND BIOLOGICAL OPINION In 1999, FPL exceeded their anticipated incidental take limit established by the 1997 Biological Opinion (BO) set forth by NMFS. This required reinitiation of consultation under Section 7 of the Endangered Species Act. As part of this consultation, FPL, through Ecological Associates Inc., submitted a report entitled "Physical and Ecological Factors Influencing Sea Turtle Entrainment Levels at the St. Lucie Nuclear Power Plant:
1976-1998." NMFS received the report in March 2000 and considered this new information when developing the new Opinion. On May 4, 2001, NMFS issued it's BO as part of the reinitiation of consultation subsequent to the 1997 BO.
iv
St. Lucie Units 1 and 2 Docket Nos. 50-335 and 50-389 L-2003-111 Enclosure In the new Opinion there were a number of changes, most importantly the incidental take statement. This, in summary, stated that FPL will exceed their take limits for a calendar year if: more than 1000 sea turtles are captured, or 1 percent or more of the total number of loggerhead and green turtles (combined) are injured or killed causal to plant operation, or more than two Kemp's Ridley sea turtles are injured or killed causal to plant operation, or if any hawksbill or leatherback sea turtles are injured or killed causal to plant operation. In a case where 1 percent of the combined loggerhead and green turtle captures are not a whole number, it is rounded up (e.g. 1% of 520 combined captures equals a take limit of 6). If any of these events occur, reinitiation of a Section 7 consultation will be required.
V
St. Lucie Units I and 2 Docket Nos. 50-335 and 50-389 L-2003-111 Enclosure
2.0 INTRODUCTION
2.1 BACKGROUND
This document has been prepared to satisfy the requirements contained in Appendix B, Environmental Protection Plan, to St. Lucie Unit 1 and 2 Facility Operating Licenses DPR-67 and NPF-16, respectively.
St. Lucie Units 1 and 2 use the Atlantic Ocean as a source of water for once-through condenser cooling. Since 1971, the potential environmental effects resulting from the intake and discharge of this water have been the subject of FPL sponsored biotic studies at the site. Jurisdiction for sea turtle studies is with the NRC, which is considered to be the lead federal agency relative to consultation under the Endangered Species Act. Previous results dealing with sea turtle studies are contained in 19 annual environmental operating reports covering the period from 1983 through 2001. This report describes the 2002 environmental protection activities related to sea turtles, as required by Subsection 4.2 of the St. Lucie Units 1 and 2 Environmental Protection Plans.
2.2 AREA DESCRIPTION The St. Lucie Plant is located on a 457-hectare site on Hutchinson Island on Florida's east coast (Figures 1 and 2). The plant is approximately midway between Ft. Pierce and St. Lucie Inlets. It is bounded on the east side by the Atlantic Ocean and on the west side by the Indian River Lagoon. Hutchinson Island is a barrier island that extends 36 km between inlets and attains its maximum width of 2 km at the plant site.
Elevations approach 5 m atop dunes bordering the beach and decrease to sea level in the mangrove swamps that are common on the western side. The Atlantic shoreline of Hutchinson Island is composed of sand and shell hash with intermittent rocky promontories protruding through the beach face along the southern end of the island.
Submerged coquinoid rock formations parallel much of the island off the ocean beaches. The ocean bottom immediately offshore from the plant site consists primarily of sand and shell sediments. The Florida Current, which flows parallel to the continental shelf margin, begins to diverge from the coastline at West Palm Beach. At Hutchinson Island, the current is approximately 33 km offshore. Oceanic water associated with the western boundary of the current periodically meanders over the inner shelf, especially during summer months.
2.3 PLANT DESCRIPTION The St. Lucie Plant consists of two 850 net MWe nuclear-fueled electric generating units that use near shore ocean waters for the plant's once-through condenser cooling system. Water for this system enters through three submerged intake structures located about 365 m offshore (Figure 2). The intake structures are equipped with a velocity cap to minimize fish entrainment. Water passes through these structures and I
St. Lucie Units I and 2 Docket Nos. 50-335 and 50-389 L-2003-111 Enclosure into submerged pipes (two 3.7 m and one 4.9 m in diameter) running under the beach.
It then passes into a 1,500 m long intake canal, which transports it to the plant. After passing through the plant, the heated water is discharged into a 670 m long canal that leads to two buried discharge pipelines. These pass underneath the dunes and along the ocean floor to the submerged discharges, the first of which is approximately 365 m offshore and 730 m north of the intake.
2
St. Lucie Units I and 2 Docket Nos. 50-335 and 50-389 L-2003-111 Enclosure 3.0 SEA TURTLE PROGRAM
3.1 INTRODUCTION
Hutchinson Island, Florida, is an important rookery for the loggerhead turtle, Caretta caretta, and also supports nesting of the green turtle, Chelonia mydas, and the leatherback turtle, Dermochelys coriacea. State and federal statutes protect all three species. The federal government has classified the loggerhead turtle as a threatened species. The leatherback turtle and the Florida nesting population of the green turtle are listed by the federal government as endangered species. It has been a prime concern of FPL that the St. Lucie Plant would not adversely affect the Hutchinson Island rookery. Because of this concern, FPL has sponsored monitoring of marine turtle nesting activity on the island since 1971.
Daytime surveys to quantify nesting, as well as nighttime turtle tagging programs, were conducted in odd numbered years from 1971 through 1979. During daytime nesting surveys, nine 1.25 km-long survey areas were monitored five days per week (Figure 3).
The St. Lucie Plant began operation in 1976; therefore, the first three survey years (1971, 1973, and 1975) were pre-operational. Though the power plant was not operating during 1975, St. Lucie Plant Unit No. I ocean intake and discharge structures were installed during that year. Installation of these structures included nighttime construction activities conducted offshore from and perpendicular to the beach.
Construction had been completed and the plant was in full operation during the 1977 and 1979 surveys.
A modified daytime nesting survey was conducted in 1980 during the preliminary construction of the ocean discharge structure for St. Lucie Plant Unit 2. During this study, four of the previously established 1.25 km-long survey areas were monitored.
Additionally, eggs from turtle nests potentially endangered by construction activities were relocated.
Every year from 1981 through 2002, 36 one-km-long survey areas comprising the entire island were monitored seven days a week during the nesting season (Figure 3).
Beginning in 1994, the southern half of the island has been surveyed by Ecological Associates of Jensen Beach, Florida, and their data are included in this report. The St.
Lucie Plant Unit 2 discharge structure was installed during the 1981 nesting season.
Offshore and beach construction of the Unit 2 intake structure proceeded throughout the 1982 nesting season and was completed near the end the 1983 nesting season.
Construction activities associated with installation of both structures were similar to those conducted when Unit 1 intake and discharge structures were installed. Eggs from turtle nests potentially threatened by construction activities were relocated.
During 1991, another major offshore construction project was undertaken to replace damaged velocity caps on the three intake structures. A large elevated platform, from which repair activities were conducted, was erected around the three structures.
Construction occurred throughout the nesting season. However, in contrast to previous 3
St. Lucie Units 1 and 2 Docket Nos 50-335 and 50-389 L-2003-111 Enclosure offshore projects, work was restricted almost entirely to daylight hours, nighttime lighting of the work area was minimal, and no equipment or materials were used on the beach.
A sea turtle protection plan implemented in support of the project included caging of nests along a 1,500 m section of beach west of the platform and release of hatchlings to unaffected areas to the north and south. This plan was intended to mitigate any negative effects potentially resulting from required safety and navigational lighting on and near the platform.
Requirement 4.2.1 of the NRC's St. Lucie Unit 2 Appendix B Environmental Protection Plan was complete with submission of the 1986 nesting survey data (ABI, 1987). The nesting survey was continued voluntarily through 1998 with agreement from federal and state agencies. In 1998, the continuation of the nesting survey program, as well as the participation in the Sea Turtle Stranding and Salvage Network and Public Service Turtle Walks were mandated as part of the biological opinion and incidental take statement issued by the National Marine Fisheries Service. An amendment to the Environmental Protection Plan was approved in 1999, which included these requirements. Results of the 2002 nesting survey are presented in this report and discussed in relation to previous findings.
In addition to monitoring sea turtle nesting activities and relocating nests away from plant construction areas, removal of turtles from the intake canal has been an integral part of the St. Lucie Plant environmental monitoring program. Turtles entering the ocean intake structures are entrained with cooling water and rapidly transported through the intake pipes into an enclosed canal system where they must be manually captured and returned to the ocean. Since the plant became operational in 1976, turtles entrapped in the intake canal have been systematically captured, measured, weighed, tagged, and released.
Previous publications and technical reports have presented findings of the nesting surveys, nest relocation activities and canal capture program (ABI, 1994)(Quantum, 1995 through 2001). Results of studies to assess the effects of thermal discharges on hatchling swimming speed have also been reported (ABI, 1978). In July 1994, responsibility for sea turtle research and conservation activities was transferred from Applied Biology, Inc. to Quantum Resources, Inc. Methodologies employed in both the nesting surveys and canal capture operations remained essentially unchanged so that data collected in 1994 through the present are directly comparable to previous years data. The purpose of this report is to: 1) present 2002 sea turtle nesting survey data and summarize observed spatial and temporal nesting patterns since 1971, 2) document and summarize predation on turtle nests since 1971, and 3) present 2002 canal capture data and summarize comparable data collected since 1976.
4
St. Lucie Units I and 2 Docket Nos. 50-335 and 50-389 L-2003-111 Enclosure 3.2 MATERIALS AND METHODS 3.2.1 Nesting Survey Methodologies used during turtle nesting surveys on Hutchinson Island are described in earlier reports (ABI 1994). In 2002, similar methods were used and surveys were designed to allow comparisons with these previous studies.
In 2002, only areas C - S were surveyed by Quantum Resources biologists (Figure 3).
Ecological Associates, Inc. surveyed areas A - C as part of a beach renourishment project south of Ft. Pierce inlet. Data from those areas as well as the south end of Hutchinson Island were supplied by Ecological Associates, Inc. and were used to provide whole island nesting totals in Figures 6, 8, and 9.
From mid-March 2002 through April 14, 2002, several preliminary nest surveys were conducted along Hutchinson Island in areas C - S. Eight leatherback nests were recorded in areas C - S prior to the beginning of formal nesting surveys on April 15, 2002. From April 15, 2002 through September 15, 2002, nest surveys were conducted on a daily basis. The last nest recorded in area C - S was a green turtle nest on September 11, 2001. Biologists used all terrain vehicles to survey the island each morning. New nests, non-nesting emergences (false crawls), and nests destroyed by predators were recorded for each of the 1-km-long survey areas A - S (Figure 3).
Data collected from beach nesting surveys were reported to the Florida Fish and Wildlife Conservation Commission (FFWCC) as part of the FFWCC Index Nesting Beach Survey and the Statewide Nesting Beach Survey. In a cooperative effort, data from stranded turtles found during beach surveys were routinely provided to the Florida Department of Environmental Protection and the National Marine Fisheries Service (NMFS) through the Sea Turtle Stranding and Salvage Network.
3.2.2 Intake Canal Monitoring Most turtles entrapped in the St. Lucie Plant intake canal were removed by means of large-mesh tangle nets fished near the intake canal headwalls at the extreme eastern end of the intake canal (Figure 2). Nets used during 2002 were from 30 to 40 m in length, 3 to 4 m deep and composed of 40 cm stretch mesh multifilament nylon. Large floats were attached to the surface, and unweighted lines used along the bottom.
Turtles entangled in the nets generally remained at the water's surface until removed.
Since its inception in 1976, the canal capture program has been under continual review and refinement in an attempt to minimize both entrapment time and injuries/mortalities to entrapped sea turtles. Prior to April 1990, turtle nets were usually deployed on Monday morning and retrieved on Friday afternoon. During periods of deployment, the nets were inspected for captures at least twice each day (mornings and afternoons).
Additionally, St. Lucie Plant personnel checked the nets periodically, and biologists were notified immediately if a capture was observed. Sea turtle specialists were on call 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> a day to retrieve captured turtles from the plant intake canal system.
5
St. Lucie Units I and 2 Docket Nos. 50-335 and 50-389 L-2003-111 Enclosure Beginning April 1990, after consultation with NMFS, net deployment was scaled back to daylight hours only. Concurrently, surveillance of the intake canal was increased and biologists remained on site for the duration of each day's netting activities. This measure decreased response time for removal of entangled turtles from nets and provided an opportunity to improve daily assessments of turtle levels within the canal.
Records of daily canal observations were compared with capture data to assess capture efficiencies.
In 1978, a barrier net at the AMA bridge was constructed to confine turtles to the easternmost section of the intake canal, where capture techniques have been most effective. This net is constructed of large diameter polypropylene rope and has a mesh size of 20.3 cm x 20.3 cm. A cable and series of large floats are used to keep the top of the net above the water's surface, and the bottom is anchored by a series of concrete blocks. The net is inclined at a slope of 1:1, with the bottom positioned upstream of the surface cable. This reduces bowing in the center and minimizes the risk of a weak or injured turtle being pinned underwater by strong currents.
In the past, the integrity of the barrier net was occasionally compromised, and turtles were able to move west of AlA. These turtles were further constrained downstream by an underwater intrusion detection system (UIDS) consisting, in part, of a large barrier positioned perpendicular to the north-south arm of the canal (Figure 2). The UIDS security barrier has a mesh size of 22.9 cm x 22.9 cm. Prior to completion of the UIDS in December 1986, turtles unconfined by the AIA barrier net were usually removed from the canal at the intake wells of Units 1 and 2 (Figure 2). There they were retrieved by means of large mechanical rakes or specially designed nets. Following construction of the UIDS barrier, only the smallest individuals were able to reach the intake wells.
Improvements made to the AMA barrier net during 1990 have effectively confined all turtles larger than 32.5 cm carapace length (28.7 cm carapace width) to the eastern end of the canal.
In response to the large numbers of small green turtles encountered in the intake canal in recent years, an improved design, small mesh barrier net was erected east of the AMA barrier net and was completed in January 1996. This barrier net was designed to confine all turtles with a carapace width greater than 18 cm to the extreme eastern portion of the intake canal. However, the integrity of this net was often compromised by incursions of seaweed, drift algae, jellyfish and siltation. During these events water velocities around the net increased dramatically creating a compromised net slope that caused several sea turtle mortalities. To address this design problem and to further alleviate mortalities FPL constructed a new net, with stronger mesh and added support structures. Dredging of the canal east of the AMA net was also conducted to minimize water velocities around the new barrier net. Construction was completed in November 2002. These improvements should enable the new net to withstand the events that caused design failure of the old barrier net, thus reducing the potential for sea turtle mortalities.
6
St. Lucie Units 1 and 2 Docket Nos. 50-335 and 50-389 L-2003-111 Enclosure Formal daily inspections of the intake canal were made to determine the numbers, locations, and species of turtles present. Surface observations were augmented with periodic underwater inspections, particularly in and around the barrier nets.
In addition to the use of tangle nets, dip nets and hand captures using snorkel and SCUBA were also employed. Long handled dip nets employed from small boats, the canal banks, and headwall structures were moderately effective in capturing turtles with carapace lengths of about 30 cm or less. Divers were employed to hand capture turtles whenever underwater visibility permits, and this technique has proven highly effective in the capture of turtles of all sizes, particularly less active individuals often found partially buried in the sediment in the vicinity of the barrier nets. Hand capture efforts have had a significant impact in reducing entrapment times for turtles in the intake canal.
Regardless of capture method, all turtles removed from the canal were identified to species, measured, weighed, tagged, and examined for overall condition (wounds, abnormalities, parasites, etc.). Beginning in July 1994, all turtles captured have been photographed dorsally and ventrally prior to release, and the photographs retained for future reference. Additionally, beginning in July 2001, Passive Integrated Transponder tags (PIT tags) were injected subcutaneously into the right front flipper of all captured turtles as outlined in the Biological Opinion issued by NMFS in May 2001. Healthy turtles were released into the ocean the same day of capture. Sick or injured turtles were treated and occasionally held for observation prior to release. When treatment was warranted, turtles were transported to an approved rehabilitation facility after consultation with FFWCC.
Resuscitation techniques were used if a turtle was found that appeared to have died recently. Beginning in 1982, necropsies were conducted on dead turtles found in fresh condition. All fresh dead turtles were held on ice for inspection and necropsy by FFWCC or frozen for future necropsy as per FFWCC direction.
Florida Power & Light Company and Quantum Resources, Inc., continued to assist other sea turtle researchers in 2002. Since the program began, data, specimens and/or assistance have been given to the Florida Department of Environmental Protection, National Marine Fisheries Service, US Fish and Wildlife Service, Marine Turtle Specialist Group, US Army Corps of Engineers, Smithsonian Institution, South Carolina Wildlife and Marine Resources Division, Center for Sea Turtle Research (University of Florida), Florida Atlantic University, University of Central Florida, Texas A & M University, University of Rhode Island, University of South Carolina, University of Illinois, University of Georgia, Virginia Institute of Marine Science, Duke University Marine Lab, Western Atlantic Turtle Symposium, South Atlantic Fishery Management Council, Florida Marine Fisheries Commission, Harbor Branch Oceanographic Institution and the National Research Council.
7
St. Lucie Units 1 and 2 Docket Nos. 50-335 and 50-389 L-2003-111 Enclosure 3.3 RESULTS AND DISCUSSION 3.3.1 Nestinq Survey 3.3.1.1 2002 LoQgerhead Nesting SummarV In 2002, 6426 loggerhead turtle nests were recorded in the 36 one-kilometer segments comprising Hutchinson Island. This figure is a slight departure from the 2001 nesting year, but is in accordance with a general increase in loggerhead turtle nesting on Hutchinson Island since surveys began in 1971 (Figure 4).
3.3.1.2 Spatial Distribution of Loggerhead Turtle Nests From 1981 through 2002, 36 one-km-long segments comprising the island's coastline have been surveyed. The distribution of nests among these 36 survey areas has shown an increase in nesting from north to south along the northern half of the island (ABI, 1987, 1994). Though beach dynamics may sometimes affect the selection of nesting sites by loggerhead turtles, relationships between spatial nesting patterns and specific environmental conditions are often difficult to establish because of the interrelationship of the factors involved.
Not all ventures onto the beach by a female turtle culminate in successful nests. These "false crawls" (non-nesting emergences) may occur for many reasons and are commonly encountered at other rookeries. Davis and Whiting (1977) suggested that relatively high percentages of false crawls might reflect disturbances or unsatisfactory nesting beach characteristics. Therefore, certain factors may affect a turtle's preference to emerge on a beach, while other factors may affect a turtle's tendency to nest after it has emerged. An index, which relates the number of nests to the number of false crawls in an area, is useful in estimating the post-emergence suitability of a beach for nesting. In the present study this index is termed "nesting success" and is defined as the percentage of total emergences that result in nests (Figure 5).
Historically, the pattern of loggerhead emergences on the island has paralleled the distribution of nests (ABI, 1987, 1994) and nesting success has lacked gradients.
However, in recent years zones A through C have experienced lower nesting success due to beach renourishment activities conducted just south of Ft. Pierce Inlet. This temporary drop in nesting success has been reported at other renourished beaches throughout Florida (Steiniteet al. 1998; Herren, 1999).
A variety of environmental factors (i.e., offshore bottom contours, distribution of reefs, type and extent of dune vegetation, and human activity on the beach at night) may effect loggerhead turtle emergence patterns and several have been reported to affect emergence patterns on Hutchinson Island (ABI, 1988, 1989). Undoubtedly, a combination of factors accounts for the overall distribution of emergences and therefore the overall nesting pattern on the island.
8
St. Lucie Units 1 and 2 Docket Nos. 50-335 and 50-389 L-2003-111 Enclosure Nesting surveys on Hutchinson Island were initiated in response to concerns that the operation of the St. Lucie Plant might negatively impact the local sea turtle rookery.
Previous analysis, using log-likelihood tests of independence (G-test; Sokal and Rohlf, 1981) demonstrated that the construction of the plant's offshore intake and discharge structures significantly reduced nesting at the plant site during construction years --
1975, 1981, 1982, 1983 (ABI, 1987). However, nesting at the plant consistently returned to levels similar to or greater than those at a control site in years following construction. During 1991 when offshore construction was restricted almost entirely to daylight hours, nests were more abundant at the plant site than at the control site. Data collected through 2002 have shown that power plant operation exclusive of nighttime intake/discharge construction has had no apparent effect on nesting.
3.3.1.3 Long-Term Trends in Loggerhead Turtle Nesting Various methods were used during surveys prior to 1981 to estimate the total number of loggerhead nests on Hutchinson Island based on the number of nests found in the nine 1.25 km-long survey areas (ABI, 1980a). Each of these methods was subsequently found to consistently overestimate island totals (ABI, 1987). Since whole-island surveys began in 1981, it has been possible to determine the actual proportion of total nests deposited in the nine areas. This has allowed extrapolation from the nine survey areas to the entire island for years 1981 to 2000. In 2001, these nine 1.25 km sections were abandoned and whole island surveys were conducted in the existing 36 one-kilometer segments.
From 1981 through 1993, the total number of nests in the nine areas varied from 32.5 to 35.6% of the total number of nests on the island. This is slightly higher than the 31.3%
that would be expected based strictly on the proportion of linear coastline comprised by the nine areas. Using the 13-year mean of 33.81%, estimates of the total number of nests on Hutchinson Island can be calculated by multiplying the number of nests in the nine areas by 2.958. This technique, when applied to the nine survey areas during the 13 years in which the entire island was surveyed, produced whole-island estimates within 5.3% of the actual number of nests counted. Because the proportion of nests recorded in the nine survey areas remained relatively constant over the last 13 years, this extrapolation procedure provides a fairly accurate estimate of total loggerhead nesting for years prior to 1981, and is used to generate data points for 1971 through 1979 in Figure 6.
It is clear that loggerhead nesting activity on Hutchinson Island fluctuates considerably from year to year (Figure 6). Annual variations in nest densities are also common at other rookeries, and probably result from non-annual reproductive behavior. No relationships between total nesting activity and power plant operation or intake/discharge construction were indicated by year-to-year variations in total nesting on Hutchinson Island.
9
St. Lucie Units 1 and 2 Docket Nos. 50-335 and 50-389 L-2003-111 Enclosure 3.3.1.4 Seasonal Patterns of Loggerhead Turtle Nesting The loggerhead turtle nesting season usually begins between mid-April and early May, attains a maximum during June or July, and ends by mid-September (ABI, 1987).
Nesting activity during 2002 followed this same pattern.
Cool water intrusions frequently occur over the continental shelf of southeast Florida during the summer (Smith, 1982). These intrusions may have been responsible for the temporary declines in loggerhead turtle nesting activity previously observed on Hutchinson Island (ABI, 1994). Though natural fluctuations in temperature have been shown to affect temporal nesting patterns on Hutchinson Island, there has been no indication that power plant operation has affected these temporal patterns (ABI, 1988).
3.3.1.5 Predation on Loggerhead Turtle Nests Since nest surveys began in 1971, raccoon predation has been a major cause of turtle nest destruction on Hutchinson Island. Researchers at other locations have reported raccoon predation levels as high as 70 to nearly 100 percent (Hopkins et al., 1979).
Raccoon predation of loggerhead turtle nests on Hutchinson Island has not approached this level during any study year, though levels for individual 1.25 km-long areas have been as high as 80 percent. Overall predation rates for survey years 1971 through 1977 were between 21 and 44 percent, with a high of 44 percent recorded in 1973. A pronounced decrease in raccoon predation occurred after 1977 and overall predation rates for the nine areas have not exceeded 10 percent since 1979. A decline in predation rates on Hutchinson Island may be attributable to trapping programs, construction activities, habitat loss, and disease.
During 2002, raccoon predation levels increased on the island. Raccoons in areas A -
S (Figure 7) depredated a total of 163 loggerhead nests. The bulk of these raccoon predations occurred in areas N - S and were thought to be caused by a small number of animals. As in previous years (ABI, 1994), the predation of turtle nests was primarily restricted to the more undeveloped portions of the island.
Ghost crabs have been reported by numerous researchers as important predators of sea turtle nests (Hopkins et al., 1979; Stancyk, 1982). Though turtle nests on Hutchinson Island probably have been depredated by ghost crabs since nesting surveys began in 1971, quantification of ghost crab predation did not begin until 1983.
Overall predation rates by ghost crabs have varied from 0.1 to 2.1 percent from 1983-2002. During 2002, 20 loggerhead nests in areas A - S were depredated by ghost crabs (Figure 7). Nests destroyed by a combination of raccoon and ghost crab predation have been included as raccoon predations in previous discussions. When these combination predations are included as crab predations, the overall predation rates by ghost crabs range from 0.1 to 4.7 percent. During 2002, 26 such combination predations were recorded. However, due to the cryptic nature of these predators, ghost 10
St. Lucie Units 1 and 2 Docket Nos. 50-335 and 50-389 L-2003-111 Enclosure crab predation in areas A - S is potentially much greater than what has been presented here.
3.3.1.6 2002 Green and Leatherback Nesting Summary In 2002, 502 green turtle and 151 leatherback turtle nests were recorded in the 36 one-km segments comprising Hutchinson Island. The green turtle nest total represents a whole island record and a substantial increase from the previous high nesting year of 2000 (Figures 8 and 9). Although year to year fluctuations are common, the general trend since 1971 may reflect an increase in the number of nesting females of both species in the Hutchinson Island area.
3.3.1.7 Trends in Green and Leatherback Turtle Nestinq Green and leatherback turtles nest on Hutchinson Island, but in fewer numbers than loggerhead turtles. Prior to 1981, both survey (nine 1.25 km-long sections) and inter-survey areas were monitored for the presence of green and leatherback nests. Thirty-one kilometers of beach from area 1 south to the St. Lucie Inlet were included in that effort. During whole-island surveys from 1981 through 1993, only 2.6 percent (7) of the leatherback nests (n=266) and only 1.4 percent (12) of the green turtle nests (n=831) were recorded on the five kilometers of beach north of area 1. Therefore, previous counts of green and leatherback nests within the 31 kilometers surveyed probably were not appreciably different from total densities for the entire island. Based on this assumption, green and leatherback nest densities may be compared among all survey years, except 1980, when less than 15 kilometers of beach were surveyed.
Since surveys began in 1971, the number of nests observed on the island has ranged from 5 to 502 for green turtles and from I to 232 for leatherbacks (Figures 8 and 9).
Temporal nesting patterns for these species differ from the pattern for loggerhead turtles. Green turtles typically nest on Hutchinson Island from mid-June through the first or second week of September. Leatherback turtles usually begin nesting in March or April and continue to nest through early to mid-July. Considerable fluctuations in green turtle nesting on the island have occurred among survey years (Figure 8). This is not unusual since there are drastic year-to-year fluctuations in the numbers of green turtles nesting at other breeding grounds (Carr et al., 1982). Despite these fluctuations, data collected through 2002 suggest an overall increase in nesting since 1971 and may reflect an increase in the number of nesting females in the Hutchinson Island area.
Similar to previous surveys, green turtles nested in greater numbers along the southern half of the island.
Leatherback turtle nest numbers for 2002 represent another high year and are consistent with an increase in nesting densities on Hutchinson Island during recent years (Figure 9). This increase in leatherback nesting has not only been reported for Hutchinson Island but for nesting beaches to the north and south and may reflect an overall increase in the number of nesting females on the Atlantic coast of Florida.
11
St. Lucie Units I and 2 Docket Nos. 50-335 and 50-389 L-2003-111 Enclosure 3.3.2 INTAKE CANAL MONITORING Entrainment of sea turtles at the St. Lucie Plant has been attributed to the presumed physical attractiveness of the offshore structures housing the intake pipes rather than to plant operating characteristics (ABI, 1980b and 1986). The velocity caps, which are supported above the openings to each intake pipe, eliminate vertical water entrainment and substantially reduce current velocities near the structures by spreading horizontal draw over a wider area. Even when both units are operating at full capacity, turtles must actively swim into the mouth of one of the pipes before they encounter current velocities sufficiently strong enough to entrain them. Consequently, a turtle's entrapment relates primarily to the probability that it will detect and subsequently enter one of the intake structures.
3.3.2.1 2002 Canal Capture Summary In 2002, 636 sea turtles were captured in the intake canal of the St. Lucie Plant.
Captures included 292 green turtles, 341 loggerheads and 3 hawksbills (Table 1).
3.3.2.2 Relative Abundance and Temporal Distribution Since intake canal monitoring began in May 1976, 4835 loggerhead (including 374 recaptures), 3581 green (including 962 recaptures), 24 leatherback, 36 Kemp's ridleys, and 33 hawksbill captures have taken place at the St. Lucie Plant. Annual catches for all species combined ranged from a low of 33 in 1976 (partial year of plant operation and monitoring) to 933 in 1995.
Historically, loggerheads have been the most abundant species in the canal Since 1977, the first full year of plant operation, the number of loggerheads captured each year ranged from 62 in 1981 to 393 in 1998 (Figure 10). Numbers have exhibited considerable year-to-year fluctuations with no persistent trends evident, although recent years data are suggestive of a possible increasing trend.
The number of green turtles captured each year since 1977 have ranged from 3 in 1979 to a record high of 673 in 1995 (Figure 10). The increasing number of captures over recent years reflects an increase in the number of turtles inhabiting the nearshore coastal area near the plant. Green turtle captures decreased slightly in 2002, but were still well above the long term average. Additional years of capture data will be required before any long-term trends can be established.
During 2002, the monthly catch of loggerheads ranged from 10 (October) to 51 (March),
with a monthly mean of 28.4 (Table 2). Over the entire history of the capture program, monthly catches have ranged from 0 to 87, with the greatest number of captures occurring during July 1996.
During 2002, the monthly catch of green turtles ranged from 15 (April) to 40 (June), with a monthly mean of 24.3 (Table 3). The March 1996 catch of 147 green turtles is the 12
St. Lucie Units 1 and 2 Docket Nos. 50-335 and 50-389 L-2003-111 Enclosure largest number of captures, for any species, for any month on record. In the past, seasonal abundance patterns of green turtles have typically been much more pronounced than for loggerheads, with over 50 percent of all captures occurring between January and March. From 1995 through 2002, however, no such seasonal pattern was evident, with captures distributed more or less evenly throughout the year.
Catches of leatherbacks, hawksbills and Kemp's ridleys have been infrequent and scattered throughout the years. Each species has shown rather pronounced seasonal occurrences; over 60 percent of all leatherbacks were captured in March and April, over 60 percent of the hawksbills were captured between July and September, and almost 90 percent of the Kemp's ridleys were caught between December and April.
3.3.2.3 Size-Class Distributions The size-class distribution for loggerheads removed from the intake canal in 2002 is presented in Figure 11. The size class distribution for green turtles removed from the intake canal in 2002 is presented in Figure 12. ABI (1994) presents size-class data for turtles removed from the intake canal from 1976-1993. The hawksbills captured in 2002 were two juveniles and one adult female (Witzell, 1983).
3.3.2.4 Sex Ratios Of the 341 loggerheads captured in 2002 for which straight line carapace lengths are available, 229 were juveniles with a straight line carapace length (SLCL) less than or equal to 70 cm, 53 were adults (SLCL > 85 cm) and 59 were transitional (SLCL 71-85 cm) (Hirth, 1980). The latter group probably includes both mature and immature individuals. Of the 53 individuals classified as adults for which sex was recorded, 43 were females and 9 were males, with females predominating by a ratio of 5:1.
Of the 292 green turtles captured in 2002 for which straight line carapace lengths are available, 283 were juveniles or sub-adults (SLCL < 83 cm) and 9 were adults (SLCL >
83 cm)(Whitherington and Ehrhart, 1989). Of the 9 individual adult green turtles captured, 4 were female and 5 were male; a ratio of 1:1. ABI (1994) discusses sex ratio data for previous years for both species mentioned here.
3.3.2.5 Capture Efficiencies Netting methodologies have been under continual review and refinement as net materials, configurations, and placement has been varied in an effort to minimize sea turtle entrapment times. Additionally, alternative capture techniques have been evaluated, and potential deterrent systems tested in the laboratory. Current capture procedures have proven to provide a safe, efficient, and cost-effective program for removing entrapped turtles from the intake canal.
Formal daily inspections of the intake canal are conducted every day that capture nets are deployed, and the number, location and relative size of entrapped turtles are 13
St. Lucie Units 1 and 2 Docket Nos. 50-335 and 50-389 L-2003-111 Enclosure recorded on field observation forms. Better utilization of currents and eddies, adjustments to tethering lines, multi-net deployments and increased efforts to hand capture turtles have contributed to reduced entrapment times during recent years.
Entrapment times may be extended for turtles swimming past the AlA barrier net (ABI, 1987). Because capture efforts west of the AlA bridge were generally less effective than those near the intake headwalls, most turtles breaching the AlA barrier net were not caught until they entered the intake wells of Units 1 and 2. Several times during 2002 the effectiveness of the primary 5" barrier net (east of the AlA net) was compromised due to holes or large influxes of drift algae. During these events, some turtles were able to breach the primary barrier net and only the larger turtles were effectively contained east of the AlA net. During these brief occurrences, special nets were set between the two barrier nets and divers were used in an effort to capture turtles stuck in the 150 meters of canal between the two barrier nets. In 2002, 16 of the 636 (2.5 percent) turtles captured at the intake canal were captured between the two barrier nets; 10 loggerheads and 6 green turtles.
Because of their relatively small sizes, virtually all the turtles reaching the intake wells are green turtles. During 2002, 5 of the 292 green turtle captures (1.7 percent) occurred at the intake wells. The substantial decrease in the percentage of captures at the plant intake wells compared to the 1995 figure of 14.5 percent is attributed to the effectiveness of the small mesh barrier net installed east of AIA in January 1996. The new 5-inch barrier net which was installed November 2002 has better support structures, stronger mesh material, and should further reduce the percentage of turtles captured at the intake wells.
During 2002, 99.2 percent of all turtles entrapped in the canal were captured east of the AlA bridge, 540 by tangle nets and 39 by hand or dip net capture. The effective confinement of turtles east of AlA has been a major contributor to the high capture efficiency achieved during recent years. The installation of an improved barrier net completed in November 2002 should further increase capture efficiency by more effectively confining turtles of all sizes to an even smaller area, closer to the headwalls.
3.3.2.6 Barrier Net Maintenance Barrier net maintenance is critical in reducing the opportunity for mortalities in the plant intake well area and in reducing residence times for turtles in the intake canal system.
Daily inspections are performed from a small boat to remove floating debris and to repair holes near or at the water surface. A formal inspection is conducted quarterly, including hole repair, debris removal, and airlift dredging of accumulated silt, if needed.
Maintenance conducted in 2002 included the repair of any holes in the mesh discovered during the daily and quarterly inspections and extensive debris removal and airlift dredging of accumulated sediment. In November 2002, the construction of the improved barrier net was completed. This new net has improved structural support, stronger mesh material, and includes a venturi silt removal system at the base of the 14
St. Lucie Units I and 2 Docket Nos. 50-335 and 50-389 L-2003-111 Enclosure net. In theory, this silt removal system should eliminate the frequency of maintenance airlift dredging.
During 2002, the primary barrier net was lowered below the surface of the water on three occasions. These events occurred during four days in August, one day in September and four days in October. The first event was caused by large influxes of drift algae into the canal system. This caused the slope of the barrier net to be compromised and ultimately fail. During this sea weed event, divers were quickly brought in to free the net of debris and return it to normal working order. The second and third net lowering events were associated with the construction and installation of the new small mesh barrier net.
3.3.2.7 Relative Condition Turtles captured alive in the intake canal of the St. Lucie Plant were assigned a relative condition based on weight, activity, parasite infestation, barnacle coverage, wounds, injuries, and any other abnormalities which might affect overall vitality. During 2002, 91.8 percent (313) of all loggerheads found in the canal were alive and in good condition. Only 8.2 percent (28) of all loggerhead captures involved individuals in fair or poor condition. Of the 292 green turtles removed from the intake canal during 2002, 97.0 percent (283) were in good condition, 2.1 percent (6) were in fair or poor condition and 1.0 percent (3) were dead. Conditions for all other sea turtles captured at the intake canal in 2002 were categorized as good.
Relative condition ratings can be influenced by a number of factors, some related and others unrelated to entrainment and/or entrapment in the intake canal. A rating of good indicates that turtles have not been negatively impacted by their entrapment in the canal, at least as evidenced by physical appearance. Although ratings of fair or poor imply reduced vitality, the extent to which entrainment and entrapment is responsible is often indeterminable. In some instances, conditions responsible for lower ratings, such as boat collision or fisheries gear entanglement injuries obviously were sustained prior to entrainment. However, recently turtles have been found with fresh scrapes and cuts, incurred during entrainment, which in some cases have had a negative effect on their relative condition rating.
Of the 633 live removals during 2002, 612 were released into the ocean on the day of capture. Fifteen loggerheads and three green turtles in obvious ill health or suffering serious injuries were transported to either Sea World of Florida, the Marinelife Center of Juno Beach, the Turtle Hospital in Marathon, or to Clearwater Aquarium for treatment and rehabilitation. None of these injuries were determined to be causal to plant operation. Eleven green turtles with fibropapilloma tumors were captured and released from the canal in 2002.
15
St. Lucie Units 1 and 2 Docket Nos. 50-335 and 50-389 L-2003-111 Enclosure 3.3.2.8 Mortalities Sea turtle mortalities have been closely monitored throughout the life of the canal capture program in an attempt to assign probable causes and take appropriate remedial action to minimize future occurrences. Previous analyses of capture data identified drowning in nets (AlA barrier net, UIDS barrier, and tangle nets), drowning in the intake pipes during periods of reduced intake flow, injuries sustained from dredging operations and injuries sustained from the mechanical rakes used in the intake wells as probable mortality factors (ABI, 1987)(FPL, 1995). Although difficult to quantify, the entrapment and subsequent demise of injured or sick turtles has probably accounted for a portion of observed mortalities.
Over the entire monitoring program history, 140 (2.9 percent) of the 4835 loggerheads and 66 (1.8 percent) of the 3581 green turtles entrapped in the canal were found dead.
Mortalities spanned the range of size classes for loggerheads (SLCL = 47.5-103 cm),
while all green turtle mortalities involved juveniles less than 42 cm in length. The four Kemp's ridley mortalities documented at the plant during 1987 and 1988 were the only deaths for this species to date; no dead leatherback or hawksbill turtles have been recovered at the St. Lucie Plant.
Modifications to capture procedures, improvements to barrier nets and virtual elimination of low flow conditions within the intake pipes have resulted in a substantial reduction in sea turtle mortalities over the life of the canal capture program. Mortality rate, expressed as the percentage of total captures involving dead animals, declined from 7.8 percent during the period 1976 - 1984 to 1.8 % since 1984, and less than 1.0 percent since 1990 (Table 1).
In 2002, three green turtles were removed dead from the intake canal, for an overall mortality rate of 0.47%. Two of these three mortalities were causal to power plant operation and went against the take limit established under the current Section 7 Biological Opinion set forth by NMFS. The two causal green turtle mortalities occurred on May 27 and June 2, 2002. The first turtle was found on the 5-inch barrier net apparently drowned. The turtle was transported to a veterinarian for necropsy. The second turtle was found dead in one of the tangle nets used for removing turtles from the canal. It apparently became severely entangled in the bottom line of the net and drowned before biologists were able to retrieve it. This turtle was also sent to a veterinarian for necropsy. A third green turtle was found dead on the barrier net on July 18, 2002. This turtle had severe injuries caused by monofilament line, wire and hooks imbedded into the base of the left front flipper. It was moderately decomposed when found and probably came into the canal either dead or in a moribund condition. This mortality was not considered causal to power plant operation.
In 1999 FPL, exceeded their anticipated incidental take limit established by the 1997 Biological Opinion (BO) set forth by NMFS. This required reinitiation of consultation under Section 7 of the Endangered Species Act. As part of this consultation FPL, through Ecological Associates Inc., submitted a report entitled "Physical and Ecological 16
St. Lucie Units 1 and 2 Docket Nos. 50-335 and 50-389 L-2003-1 11 Enclosure Factors Influencing Sea Turtle Entrainment Levels at the St. Lucie Nuclear Power Plant:
1976-1998." NMFS received the report in March 2000 and considered this new information when developing the new Opinion. On May 4, 2001, NMFS issued it's BO as part of the reinitiation of consultation subsequent to the 1997 BO. In the new Opinion, there were a number of changes, most importantly, the incidental take statement. This in summary, stated that FPL will exceed their take limits for a calendar year if: more than 1000 sea turtles are captured, or 1 percent or more of the total number of loggerhead and green turtles (combined) are injured or killed causal to plant operation, or more than two Kemp's Ridley sea turtles are injured or killed causal to plant operation, or if any Hawksbill or leatherback sea turtles are injured or killed causal to plant operation. In a case where 1 percent of the combined loggerhead and green turtle captures are not a whole number it is rounded up (e.g. 520 combined captures =
take limit of 6). If any of these events occur, reinitiation of a Section 7 consultation will be required.
3.3.2.9 Recapture Incidents Since the St. Lucie Plant capture program began, most turtles removed from the intake canal have been tagged and released into the ocean at various locations along Hutchinson Island. Consequently, individual turtles can be identified as long as they retain their tags. Over the history of the program at the St. Lucie Plant, 1336 recaptures (374 loggerheads and 962 green turtles) has occurred, and a number of turtles have been recaptured more than once. The recapture rate for green turtles in 2002 was 51.0 percent and the recapture rate for loggerheads was 7.3%. The large number of green turtle recaptures probably reflects the saturation of the local green turtle aggregation by turtles tagged at the St. Lucie Plant. Several other turtles with tag scars have also been recovered, indicating that the actual number of recaptures may be higher. The use of PIT tags, which was mandated by the current BO issued by NMFS, should alleviate any future loss of data due to tag tear outs. Occasionally, turtles are captured that have been tagged by other researchers. There were four such captures in 2002. All of these were green turtles, one from the University of Central Florida's study site in Sebastian, one of an adult male originally hatched out and tagged in Jensen Beach in 1987 and two green turtles that have yet to be accounted for.
3.3.3 OTHER SEA TURTLE PROTECTION ACTIVITIES As participants in the Sea Turtle Stranding and Salvage Network (STSSN), Quantum Resources biologists routinely respond to sea turtle strandings in St. Lucie and Martin Counties. During 2002, biologists responded to 10 sea turtle strandings. All stranding reports were sent to Florida Fish and Wildlife Conservation Commission (FFWCC).
In addition, FPL conducted 17 public service turtle walks during the 2002 nesting season. This program allowed 609 members of the public to be exposed to relevant sea turtle protection issues and, in most cases, to actually view a nesting loggerhead sea turtle.
17
St. Lucie Units 1 and 2 Docket Nos. 50-335 and 50-389 L-2003-111 Enclosure 3.3.4
SUMMARY
A gradient of increasing loggerhead turtle nest densities from north to south along the northern half of Hutchinson Island has been shown during most survey years. This gradient may result from variations in beach topography, offshore depth contours, distribution of nearshore reefs, onshore artificial lighting, and human activity on the beach at night. Low nesting activity in the vicinity of the power plant during 1975 and from 1981 through 1983 was attributed to nighttime construction activities associated with installation of power plant intake and discharge structures. Nesting returned to normal or above normal levels following both periods of construction. During 1991, daytime construction activities associated with velocity cap repairs had no apparent effect on nesting. Statistical analyses indicate that power plant operation, exclusive of nighttime construction, has had no significant effect on nest densities near the plant. In 2002, 6426 loggerhead turtle nests were recorded on Hutchinson Island. There have been considerable year-to-year fluctuations in loggerhead nesting activity on Hutchinson Island from 1971 through 2002. Fluctuations are common at other rookeries and may result from non-annual reproductive behavior. No relationship between total nesting on the island and power plant operation or intake/discharge construction was indicated.
Temporal nesting patterns of the Hutchinson Island population may be influenced by natural, large scale fluctuations in water temperature, such as those produced by the cool water intrusions that frequently occur over the continental shelf of southeast Florida during the nesting season. However, localized fluctuations in water temperature associated with power plant operation have had no apparent effect on nesting.
Since nesting surveys began in 1971, raccoon predation has been one of the major causes of turtle nest destruction on Hutchinson Island. From 1971 through 1977, overall predation rates in the nine survey areas were between 21 and 44 percent.
However, a pronounced decrease in raccoon predation occurred after 1977, and overall predation rates in the nine survey areas have not exceeded ten percent since 1979. In 2002, raccoon predation in areas N - S showed a dramatic increase from previous years, but overall predation rates for areas A - S were still well below 10%. Decreased predation by raccoons probably reflects a decline in the raccoon population. More years of survey data will be required to determine if the extremely low level of raccoon predation in 1996 through 2002 is an isolated occurrence or part of a continuing trend.
Due to their cryptic nature, ghost crab predation on turtle nests may be more significant than previously documented.
During 2002, 502 green turtle (record year) and 151 leatherback turtle nests were recorded on Hutchinson Island. Nesting activity by these two species has exhibited considerable annual fluctuations, as has been recorded at other rookeries, but has remained relatively high during recent years. This may reflect an overall increase in the number of nesting green and leatherback turtles in the Hutchinson Island area.
18
St. Lucie Units 1 and 2 Docket Nos. 50-335 and 50-389 L-2003-111 Enclosure During 2002, 341 loggerheads, 292 green turtles, and 3 hawksbills were removed from the St. Lucie Plant intake canal. Since monitoring began in May 1976, 4835 loggerhead, 3581 green, 24 leatherback, 33 hawksbill and 36 Kemp's ridley turtles have been captured and tagged. Over the life of the monitoring program, annual catches for loggerhead turtles have ranged from 33 in 1976 (partial year of plant operation and monitoring) to a high of 393 in 1998. Yearly catches of green turtles have ranged from 0 in 1976 to 673 in 1995. Differences in the number of turtles entrapped during different years and months are attributed primarily to natural variation in the occurrence of turtles in the vicinity of the offshore intake structures, rather than to plant operation characteristics.
Size-class distributions of loggerhead turtles removed each year from the canal have consistently been predominated by juveniles between 50 and 70 cm in straight-line carapace length. Over 65 percent of all green turtles entrapped in the canal were juveniles 45 cm or less in length. For both species, the largest number of captures for all years combined occurred during winter. These seasonal peaks have generally been more pronounced for green turtles, but since 1995, green turtle captures have tended to be distributed more or less evenly throughout the year. The sex ratio of adult loggerheads caught in the canal continued to be biased towards females.
During 2002, about 95 percent of all loggerheads and green turtles removed from the canal were categorized by physical appearance as being in good condition. However, fresh scrapes incurred during transport through the intake pipe have increasingly been noted on the carapace and soft tissue of captured sea turtles. Once in the canal, turtles confined east of the new barrier net had very brief residency times. Thus, the relative condition of most turtles was not affected by their entrapment.
During 2002, three mortalities were recorded in the intake canal. Two of these mortalities were causal to power plant operation, but were well short of the take limits set forth in the current Biological Opinion. Program modifications, including continual surveillance of tangle nets during periods of deployment, improvements to the integrity of the barrier net system and greater effort to hand capture turtles have contributed to a substantial decline in sea turtle mortalities during recent years. The design and construction of an improved barrier net completed in January 1996 was expected to reduce mortalities and entrapment times for turtles in the intake canal. Data since then indicate that the new barrier net configuration has been highly effective in excluding turtles from the plant intake wells, but has not been as effective in reducing the overall mortality rate as anticipated. Improvements to the barrier net design, including stronger mesh material, additional support structures, and dredging of the canal east of AlA were completed in November 2002. These modifications are expected to reduce the potential for sea turtle mortality dramatically.
19
St. Lucie Units I and 2 Docket Nos. 50-335 and 50-389 L-2003-111 Enclosure 4.0 LITERATURE CITED
- 1. ABI (Applied Biology, Inc.), 1978. Ecological monitoring at the Florida Power & Light Company St. Lucie Plant, Annual Report 1977. Volumes I and 11. AB-101.
Prepared by Applied Biology, Inc. for Florida Power & Light Company, Miami.
1980a. Florida Power & Light Company, St. Lucie Plant Annual Non-Radiological Environmental Monitoring Report 1979. Volumes II and l1l, Biotic monitoring, AB-244. Prepared by Applied Biology, Inc. for Florida Power & Light Company, Miami.
1980b. Turtle Entrainment Deterrent Study, AB-290. Prepared by AppliedBiology, Inc. for Florida Power & Light Company, Miami.
1986. Florida Power & Light Company, St. Lucie Unit 2 Annual Environmental Operating Report 1985. AB-563. Prepared by Applied Biology, Inc. for Florida Power & Light Company, Juno Beach.
1987. Florida Power and Light Company, St. Lucie Unit 2 Annual Environmental Operating Report 1986. AB-579. Prepared by Applied Biology, Inc. for Florida Power & Light Company, Juno Beach.
1988. Florida Power & Light Company, St. Lucie Unit 2 Annual Environmental Operating Report 1987. AB-595. Prepared by Applied Biology, Inc. for Florida Power & Light Company, Juno Beach.
1989. Florida Power & Light Company, St. Lucie Unit 2 Annual Environmental Operating Report 1988. AB-596. Prepared by Applied Biology, Inc. for Florida Power & Light Company, Juno Beach.
1994. Florida Power & Light Company, St. Lucie Unit 2 Annual Environmental Operating Report. AB-631. Prepared by Applied Biology, Inc., for Florida Power
& Light Company, Juno Beach.
- 2. Carr, A., A. Meylan, J. Mortimer, K. Bjorndal and T. Carr, 1982. Surveys of Sea Turtle Populations and Habitats in the Western Atlantic. NOAA Technical Memorandum NMFS-SEFC-91:1-82.
- 3. Davis, G.E., and M.C. Whiting, 1977. Loggerhead Sea Turtle Nesting in Everglades National Park, Florida, U.S.A. Herpetologica 33:18-28.
- 4. Ecological Associates Inc. 2000. Physical and Ecological Factors Influencing Sea Turtle Entrainment Levels at the St. Lucie Power Plant 1976-1998. Submitted to FPL.
20
St. Lucie Units 1 and 2 Docket Nos. 50-335 and 50-389 L-2003-111 Enclosure
- 5. FPL, 1995. Assessment of the Impacts of the St. Lucie Nuclear Generating Plant on Sea Turtle Species Found in the Inshore Waters of Florida. Florida Power and Light Company, Juno Beach, FL.
- 6. Herren, R. M. 1999. The Effect of Beach Renourishment on Loggerhead (Caretta caretta) Nesting and Reproductive Success at Sebastian Inlet, Florida. M.S. thesis University of Central Florida. 148pp.
- 7. Hirth, H.F., 1980. Some Aspects of the Nesting Behavior and Reproductive Biology of Sea Turtles. American Zoologist 20:507-523.
- 8. Hopkins, S.R., T.M. Murphy, Jr., K.B. Stansell and P.M. Wilkinson, 1979. Biotic and Abiotic Factors Affecting Nest Mortality in the Atlantic Loggerhead Turtle.
Proceeding Annual Conference of Southeastern Fish and Wildlife Agencies 32:213-223.
- 9. Quantum Resources Inc., 1995. Florida Power and Light Company, St. Lucie Unit 2 Annual Environmental Operating Report 1994. Prepared by Quantum Resources Inc. for Florida Power and Light Company, Juno Beach, FL.
1996. Florida Power and Light Company, St. Lucie Unit 2 Annual Environmental Operating Report 1995. Prepared by Quantum Resources Inc for Florida Power and Light Company, Juno Beach, FL.
1997. Florida Power and Light Company, St. Lucie Unit 2 Annual Environmental Operating Report 1996. Prepared by Quantum Resources Inc for Florida Power and Light Company, Juno Beach, FL.
1998. Florida Power and Light Company, St. Lucie Unit 2 Annual Environmental Operating Report 1997. Prepared by Quantum Resources Inc for Florida Power and Light Company, Juno Beach, FL.
1999. Florida Power and Light Company, St. Lucie Unit 2 Annual Environmental Operating Report 1998. Prepared by Quantum Resources Inc. for Florida Power and Light Company, Juno Beach, FL.
10.Smith, N.P., 1982. Upwelling in Atlantic Shelf Waters of South Florida. Florida Scientist 45(2):125-138.
11.Sokal, R.R. and F.J. Rohlf, 1981. Biometry. The Principles and Practice of Statistics in Biological Research. S.H. Freeman and Company, San Francisco. 859 pp.
12.Stancyk, S.E.,1982. Non-Human Predators of Sea Turtle and Their Control. Pages 139-152 in Bjorndal, K.A., ed. Biology and Conservation of Sea Turtles.
Smithsonian Institution Press. Washington, D.C.
21
St. Lucie Units 1 and 2 Docket Nos. 50-335 and 50-389 L-2003-111 Enclosure 13.Steinite, M. J., M. Salmon and J. Wyneken. 1998. Beach Renourishment and Loggerhead Turtle Reproduction: A Seven Year Study of Jupiter Island, Florida.
Journal of Coastal Research. 14(3):1000-1013.
14.Witherington, B.E. and L.M. Ehrhart, 1989. Status and Reproductive Characteristics of Green Turtles (Chelonia mydas) Nesting in Florida. Pages 351-352 in Ogren, L.,
F. Berry, K. Bjorndal, H. Kumpf, R. Mast, G. Medina, H. Reichart and R. Witham, editors. Proceeding of the Second Western Atlantic Turtle Symposium.Mayaguez, Puerto Rico, 12-16 October 1987. NOAA Technical Memorandum NMFS-SEFC-226.
15.Witzell, W.N. 1983. Synopsis of Biological Data on the Hawksbill Turtle Eretmochelys imbricata (Linnaeus, 1766). FAO Fisheries Synopsis, 137: 1-78.
22
St. Lucie Units 1 and 2 Docket Nos. 50-335 and 50-389 L-2003-111 Enclosure 5.0 FIGURES AND TABLES 23
St. Lucie Units 1 and 2 Docket Nos. 50-335 and 50-389 L-2003-111 Enclosure Figure 1. Location of St. Lucie Plant 24
St. Lucie Units 1 and 2 Docket Nos. 50-335 and 50-389 L-2003- 1 Enclosure Figure 2. St. Lucie Plant Cooling Water Intake and Discharge System 25
St. Lucie Units 1 and 2 Docket Nos. 50-335 and 50-389 L-2003-111 Enclosure Figure 3. Designation and Location of Nine 1.25-Km Segments and Thirty-Six 1-Km Segments Surveyed for Sea Turtle Nesting, Hutchinson Island. 1971-2002.
26
St. Lucie Units 1 and 2 Docket Nos. 50-335 and 50-389 L-2003-111 Enclosure 800 700 U)
O 600 z
w W 500 U
w o 400 z
Ul)
F 300 z
LL o 200 100 0
A B C D E F G H I J K L M N P Q R S AREA Power Plant T Figure 4. Number of loggerhead turtle nests and emergences for areas A through S, Hutchinson Island, April through September 2002.
27
St. Lucie Units I and 2 Docket Nos. 50-335 and 50-389 L-2003-111 Enclosure 100.0%
90.0%
80.0% -
- 70.0%-
enI
[ 60.0%
D 50.0%
U, Z 40.0%
U, Z 30.0%
20.0%
10.0%
0.0% t-!
A B C D E F G I
H I
I
_+__
J K L I
M I
N 0 I II P Q R S
-i AREA Power Plant t Figure 5. Loggerhead turtle nesting success (percentage of emergences resulting in nests) for areas A through S, Hutchinson Island, April through September 2002.
28
St. Lucie Units 1 and 2 Docket Nos. 50-335 and 50-389 L-2003-111 Enclosure 9000 8000 7000 CO CI-6000 z
U. 5000 0
W 4000 co z 3000 2000 1000 0
71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 00 01 02 YEAR Figure 6. Number of loggerhead nests, 1971 through 2002. Values for 1971 through 1979 are estimates (see text), values for 1981 through 2002 are from whole island surveys.
29
-, I I St. Lucie Units 1 and 2 Docket Nos. 50-335 and 50-389 L-2003-111 Enclosure UIRACCOONS ONLY 0 CRABS ONLY 0 RACCOONS & CRABS 24.0%
22.0%
20.0%
W 18.0%
a 16.0%
w t 14.0%
o 12.0%
U)
U.8.0%
0
, 6.0%
4.0%
2.0%
0.0% I I I I I 1 1. 1. -
A B C D E F G H I J K L M N O P Q R S AREA Power Plat Figure 7. Percentage of loggerhead nests predated by raccoons and/or ghost crabs in Areas A through S, Hutchinson Island, April through September 2002.
30
Il I #
St. Lucie Units 1 and 2 Docket Nos. 50-335 and 50-389 L-2003-111 Enclosure 600 500 I II I I I II I- 400 z
LL 0 300 W II z 200 100 0 I I I I 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 00 01 02 YEAR Figure 8. Number of green sea turtle nests, Hutchinson Island, 1971 through 2002. Values for 1971 through 1979 are estimates (see text). Values for 1981 through 2002 are from whole island surveys.
31
.,, p St. Lucie Units 1 and 2 Docket Nos. 50-335 and 50-389 L-2003-111 Enclosure 250 200 U,
I-w 150 z
U-0 W
M100 z
. I 50 0
71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 00 01 02 YEAR Figure 9. Number of leatherback turtle nests, Hutchinson Island, 1971 through 2002. Values for 1971 through 1979 are estimates (see text). Values for 1981 through 2002 are from whole island surveys.
32
., ,J 1 St. Lucie Units 1 and 2 Docket Nos. 50-335 and 50-389 L-2003-111 Enclosure 800 700 U0- LOGGERHEAD -A L GREEN 600 LU
-j 500 I--
LU.
0 400 w
300 I 111111I z
200 . , \ 7 In 100 :aDACit IC 0
76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 00 01 02 YEAR Figure 10. Number of loggerhead and green turtles removed each year from the intake canal, St. Lucie Plant, 1976 through 2002.
33
., I ,
St. Lucie Units 1 and 2 Docket Nos. 50-335 and 50-389 L-2003-111 Enclosure 100 -r I 90 80 C,)
uw 70
-J I-60 I-O 50 mw4 0 z 30 20 10 o
A
-P. -
IIIII I .
0)
. (1 01 a~)
0M 0)
M~C I lII M~0 C)
-L 00 CD (0
11 (O 0 )
=
V nI I I I I I I I I I I I o 1 C)L 0)
-31 C 01 C) C) O CC) VI CD (0n C C) 010 0 01 11 0 (31 01 01 O I (31 0 STRAIGHT STANDARD CARAPACE LENGTH (cm)
Figure 11. Size distribution (SSCL) of loggerhead turtles (n=341) removed from the intake canal, St. Lucie Plant, 2002.
34
,I 0 p St. Lucie Units 1 and 2 Docket Nos. 50-335 and 50-389 L-2003-111 Enclosure 70 T 60 UI 50
-j
':I- 40 U- 4o 0
W 30 l I Z 20 10 I. I 0 T I _ _
CO 0 L) 0 LO 0 LO 0 UL 0 LO 0 LO 0 LO O LO O LO O 0
'- o4 c14 CO) CO, Il s to UL CO CO I- r- co co o CD o 0 r- T I I I I I I I I I I I I o I I 'r - Ir T CoI (D (0 T- (CO - Co T- co ,'- (O D- co t- CO ' I I A C0 CY) co It " LO Lo (O CD N- - 0C0 c 0) (O O0
- 0) I " r STRAIGHT STANDARD CARAPACE LENGTH (cm)
Figure 12. Size distribution (SSCL) of green turtles (n=292) removed from the intake canal, St. Lucie Plant, 2002.
35
St. Lucie Units 1 and 2 Docket Nos. 50-335 and 50-389 L-2003-1 1 Enclosure 6.0 TABLES 36
,. 0 J St. Lucie Units 1 and 2 Docket Nos. 50-335 and 50-389 L-2003-1 11 Enclosure Species Year Loggedlrad Green Leatherback Hawksbill Kemprs rkdey Totl 1976 33 (4) 33 (4) 1977 80)5 (2) 1 86 (7) 1978 138 (19) 6(1) 3 1 148 (20) 1979 172 (13) 3(1) 175 (14) 1980 116 (5 10 (3)12 8 1981 62 (5) 32(2) 2 1 97(7) 1982 101 (16) 8 1 110 (16) 1983 119 (4) 23(4) 142 (
1984 148(69(2) 1 2 220 (5) 1985 157 (4) 14 1 172 (4) 1986 195 (27) 22(1) 1 1 1 220 (28) 1987 175 (11) 35 2 6 218 (13) 1988 134 (6 42(2) 2 5 181 (10) 1989 111(4) 179(1) 1 2 2 133 (1) 19904 12(1) 20(2) 132()
1991 127(1) 12 1 1 121 (1) 1992 1234 6 (2) 1 2 187 (4) 1993 147 179(1) 5 2 4 337 (1) 1994 164 193 (4) 2 2 361 (4) 1995 254 (1) 673 (15) 1 5 933 (16) 1996 349 (3 549 (4) 5 3 9)6 (7) 1997 188 191 (5 2 1 382 (5 1998 393 (1) 268 1 2 2 66(1) 1999 302(2 190(4) 1 1 1 495) 2000 343 (2) 346 (2) 2 691(4) 2001 271 (1) 321(5) 2 6 1 601 (6) 2002 341 292(3) 3 636 (3)
Total 4835 (140) 3581 (66) 24 33 36 (4) 89 (210)
Arrml Mean 1847 137.7 09 1.3 14 3260
- Exdudes 1976 (partial year of plant operaton).
Table 1.Total number of captured turtles removed from the intake canal, St. Lucie Plant, 1976 through 2002. Number found dead in parenthesis.
37
' is j St. Lucie Units 1 and 2 Docket Nos. 50-335 and 50-389 L-2003-111 Enclosure Number of Percent of Standard Month Captures AlI Captures Minimum Madrmujm Mean Deviation 2002 January 521 10.8% 6 39 20.0 10.1 23 February 433 9.0% 5 34 16.7 8.8 34 March 454 9.5% 1 60 17.5 15.2 51 April 472 9.8% 0 47 182 12.7 40 May 459 9.6% 0 42 17.7 13.3 42 June 501 10.4% 3 61 19.3 13.7 30 July 585 12.2% 0 87 22.5 21.1 37 August 446 9.3% 2 43 172 12.8 27 September 272 5.7% 1 26 10.5 6.9 14 October 248 52% 0 27 9.5 6.6 10 November 185 3.9% 0 18 7.1 5.0 12 December 226 4.7% 1 24 8.7 5.8 21 Totar 4802 0 87 341 Mean 4002 15.4 28.4 Std. Deviation 131.4 5.1 12.9 kExdudes 33 blggeftad captures firom 1976 (Parbal year)
Table 2. Total number of loggerhead turtles removed each month from the intake canal, St. Lucie Plant 1977 through 2002.
38
l * - X St. Lucie Units 1 and 2 Docket Nos. 50-335 and 50-389 L-2003-111 Enclosure Numberof Percent of Standard Month Captures All Captures Minimum Maximum Mean Deviation 2002 January 409 11.4% 0 61 15.7 17.2 26 February 381 10.6% 0 64 14.7 17A 27 March 454 127%/ 0 147 17.5 33.0 38 April 284 7.90/% 0 64 10.9 16.6 15 May 257 7/2% 0 91 9.9 19.5 16 June 242 6.8% 0 52 9.3 15.6 40 July 189 5.3% 0 61 7.3 13.6 22 August 232 6.5% 0 64 8.9 14.9 17 September 250 7.0% 0 77 9.6 18.1 19 October 322 9.0%/0 0 54 12.4 16.9 22 November 277 7.7% 0 50 10.7 14.7 18 December 284 7.9% 0 68 10.9 15.6 32 Total* 3581 0 147 292 Mean 298.4 11.5 24.3 Std. Deviation 78.8 3.0 8.5
- Exdudes 1976 (partial year)
Table 3. Total number of green turtles removed each month from the intake canal, St. Lucie Plant, 1977 through 2002.
39
St. Lucie Units 1 and 2 Docket Nos. 50-335 and 50-389 L-2003-111 Enclosure ANNUAL ENVIRONMENTAL OPERATING REPORT PART II
1.0 INTRODUCTION
The St. Lucie Units 1 and 2 Environmental Protection Plans (EPP) require the submittal of an annual report for various activities at the plant site including the reporting on sea turtle monitoring programs, and other matters related to federal and state environmental permits and certifications.
2.0 SEA TURTLE MONITORING AND ASSOCIATED ACTIVITIES Surveillance and maintenance of the light screen to minimize sea turtle disorientation as required by Section 4.2.3 of the EPP is ongoing. The vegetation light screen located on the beach dune between the power plant and the ocean is routinely surveyed to determine its overall vitality. Evidence of sea turtle disorientation that occurs would also indicate any significant problems. Trees, vegetation or shade cloth are replaced as necessary to maintain the overall integrity of the light screen. Plant parking lot lighting is also designed and maintained to minimize light levels on the beach.
3.0 TAPROGGE CONDENSER TUBE CLEANING SYSTEM OPERATION A Taprogge condenser tube cleaning system (CTCS) became operational on St. Lucie Unit 2 in January 1996 and on Unit 1 in July 1996. This system utilizes sponge balls, approximately 23 mm in diameter, to clean the condenser tubes through which seawater flows to cool steam after its pass through the plant's turbines. This system improves plant performance while reducing the need for chemical treatments and biocides or chlorine to control biofouling.
Normally, the St. Lucie CTCS utilizes about 1800 sponge balls, which are continually re-circulated through each of four "water boxes" on each unit. These sponge balls are retained in the system by a ball strainer located on the outlet of each water box. The ball strainers (mesh size 5 mm) are opened routinely to discharge debris, which can decrease flow and obstruct sponge ball movement through the system. The sponge balls are collected prior to opening, or back flushing, the ball strainers. At that time, the sponge balls are examined and replaced if they are worn to the point that they can no longer effectively clean the condenser tubes.
Sponge ball inventories and estimates of sponge ball loss to the environment have been performed since system start-up on both units. Number of ball strainer back flushes has also been tracked. In addition, daily beach surveys have been performed on plant property (approximately 2.5 miles) to note any sponge balls that may occur as a result of loss from the plant. This survey area has been extended during the turtle-nesting season to almost 12 miles.
40
St Lucie Units 1 and 2 Docket Nos. 50-335 and 50-389 L-2003-111 Enclosure The results of the program for 2002 are presented in Table 1. Total sponge ball losses were higher from Unit 1 than Unit 2 in 2002. This was due mostly to the peak that occurred in January on Unit 1 . This peak was attributed to loss of abrasive sponge balls immediately following the refueling outage in 2001. Only 23 sponge balls were found whole in the environment near the plant in 2002. Almost half (10) were found in January, which correlates with the higher loss on Unit 1. This number indicates that few balls actually reach the environment whole.
Figure 1 indicates that estimated sponge ball loss for both units generally remained low through the year, with the previously discussed peak in January attributed to Unit 1.
Average daily ball loss in 2002 decreased from 1998 through 2001 (Figure 2).
Estimated sponge ball loss from both units was 10.1 balls per day for 2002. This reflects a decrease of about six sponge balls per day from 2001. Average daily sponge ball loss since system start-up has been approximately 13 balls per day.
4.0 OTHER ROUTINE REPORTS The following items for which reporting is required are listed by section number from the plant's Environmental Protection Plan:
5.4.1.2(a) EPP NONCOMPLIANCES AND CORRECTIVE ACTIONS TAKEN No non-compliances under EPP Section 5.4.1(a) were determined to have occurred during 2001.
5.4.1.2(b) CHANGES IN STATION DESIGN OR OPERATION, TESTS. AND EXPERIMENTS IN ACCORDANCE WITH EPP SUBSECTION 3.1 No plant site activities were determined to be reportable under Section 5.4.1.(b) during 2001.
5.4.1.2(c) NONROUTINE REPORTS SUBMITTED TO THE NRC FOR THE YEAR 2002 IN ACCORDANCE WITH EPP SUBSECTION 5.4.2 Report concerning the mortality two green sea turtles during May 27 and June 2, 2002. The first was recovered from the 5-inch barrier net. The second was recovered from a turtle capture net. Event was reported to NRC by FPL letter L-2002-120 on June 21, 2002.
41
St. Lucie Units I and 2 Docket Nos. 50-335 and 50-389 L-2003-111 Enclosure TABLE 1 2002 ST. LUCIE PLANT CONDENSER TUBE CLEANING SYSTEM
SUMMARY
STRAINER BACK FLUSHES ESTIMATED BALL LOSS BALLS FOUND MONTH UNIT 1 UNIT 2 UNIT 1 UNIT 2 .
ON BEACH January 17 14 942* 309 10 February 17 16 113 +112 4 March 12 17 59 54 0 April 17 19 113 +81 0 May 17 16 146 +7 3 June 16 16 100 +29 1 July 18 21 176 212 0 August 17 16 179 44 1 Septemb er 16 18 211 113 3 October 1# 16 0 590 1 NovembE,r 17 17 110 182 0 DecembEer 17 18 197 62 0 Total 182 204 2346 1337 23
- Unit 1 system shutdown during refueling, 9/30 to 10/25/02.
+ Net gain in inventory.
- Loss of abrasive balls.
42
I,..q g St. Lucie Units 1 and 2 Docket Nos. 50-335 and 50-389 L-2003-111 Enclosure 55 45 40 40 -
Co Ci, 0
-J 35 -
-j
-j co 30 -
tJJ C 25 -
aCD I
1 1
5 JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC MONTH Figure 1. Estimated average daily sponge ball loss by month from St. Lucie Plant (both units) for 2002.
43
St. Lucie Units 1 and 2 Docket Nos. 50-335 and 50-389 L-2003-111 Enclosure 25 -
20 -
oo U)I0
-j
-J 15 4
-S a0 5.~
0 i l1 f1r lI- 1 1996 1997 1998 1999 2000 2001 2002 YEAR Figure 2. Average daily sponge ball loss from the St. Lucie Plant (both units) since system start-up (January 1996).
44