.4 

BIOLOGICAL AND ENGINEERING EVALUATION OF A 

FINE-PESH SCREEN INTAKE 

FOR 

BIG BEND STATION - UNIT NO. 4 

TAMPA ELECTRIC COflPkNY 

June 30, 1980 

STOKE & WEBSTER ENGINEERING CORPORATION 

BOSTON, HASSACHUSETTS 

P 
TABLE OF CONTENTS 

Part Title Tab Number 

I Fine-Mesh Screen Prototype Study - Spring 1980 . . . . . . . I ' 

I1 Conceptual Engineering Design of the Unit 3 . . . - . . . I1 

and 4 Fine-Mesh Screen Installation 

I11 Cost Comparison of Fine Mesh Screening Options . . . . . . . 111 

Versus Closed-Cycle Cooling 
a 

FOREWORD 

Tampa Electric Company's goal in providing the enclosed information isyto 

yrovide information on the cooling water system to serve Big Bend Unit No. 

4 for preliminary agency review. There are three parts to this document 

(1) the biological evaluation of fine-mesh screening technology, (2) the 

conceptual design of a fine-mesh screening system to serve Big Bend Station 

Units 3 and 4, and (3) a cost comparison of fine-mesh screening with other 

techniques for reducing entrainment. 

Part I is a review of the biological testing which has been executed to 

date to demonstrate that egg, larval, and juvenile forms of important 

species may be impinged on a filter medium, removed, and returned safely 

to the watercourse rather than allowing them to pass through the condenser 

to be subjected to thermal stress. These studies are ongoing, and the 

results presented are, therefore, preliminary. 

Part I1 proceeds from the point of having made a successful showing of 

the technology to providing an engineering design of a fine-mesh screen 

system as it would be employed at Big Bend Station. 

Part I11 provides a summary of the cost comparisons of fine-mesh screen with 

closed cycle cooling systems at Big Bend Station. 

This information will be a significant part,of TECO's 316(b) Demonstration. 
FINE; MESH SCREEN PROTOTYPE STUDY 

SPRING 1980 

BIG BEND STATION - WIT 4 

TAMPA ELECTRIC COMPANY 

JULY 1980 

STONE 6r WEBSTER ENGI-WERING CORPOR4TION 

BOSTON, MASSACHUSETTS 
L TABLE OF CONTENTS 

Section Title Page 

1 INTRODUCTION......................... 1-1 

2 DESCRIPTION OF TEST FACILITY................. 2-1 

3 SAMPLING PROCEDURES ..................... 3-1 

3.1 INTRODUCTION ........................ 3-1 

3.2 REPRESENTATIVE IMPORTANT SPECIES.............. 3-1 

3.3 PROTOTYPE SCREEN SAMPLING PROCEDURES.............3.2 

3.4 LABORATORY PROCEDURES .................... 3-3 

3.5 SUPPLEMENTAL STUDIES .....................3-5 

3.5.1 Spraywash Efficiency Sampling............... 3-5 

3.5.2 Plankton Net Sampling................... 3-5 

3.5.3 Prototype Screening Efficiency.............. 3-6 

3.5.4 Air Exposure Studies................... 3-6 

3.5.5 Organism Return System Investigations........... 3-7 

3.5.5.1 Introduction ...................... 3-7 

3.5.5.2 Flume Study ....................... 3-7 

3.5.5.3 Water Quality Measurements ............... 3-8 

3.5.5.4 Plankton Sampling ................... -3-9 

3.5.5.5 Organism Survival Studies ................3-10 

3.5.5.6 Hydrodynamic Evaluation .................3-10 

4 RESULTSTODATE ........................ 4-1 

5 CONCLUSIONS ..........................5.1 

REFERENCES 

APPENDIX 

ii 

5-
LIST OF TABLES 

Table Title 

4-1 Taxa/Life Stages Used In Initial Survivorship Analysis 

4-2 Prototype Mean Initial Survival, by Grouping as Pe.r Analysis of 

Variance (Table 4-3) 

4-3 Analysis of Variance for the Effect of Screen Speed and Approach 

Velocity on Initial Survival 

4-4 Taxa/Life Stages Used In 48 Hour Latent Survivorship Analysis 

4-5 Taxa/Life Stages Used In 96 Hour Latent Survivorship Analysis 

4-6 48 Hour Latent Survivorship 

4-7 96 Hour Latent Survivorship 

4-8 Hatchability of Eggs During Holding Experiments 

4-9 Analysis of Variance for 48 Hour Latent Survival 

4-10 Analysis of Variance for 96 Hour Latent Survival 

4-11 Latent Survival for Control Samples 

iii 

Q 
LIST OF FIGURES 

L 

Figure 

1-1 

2- 1 

2-2 

2-3 

2-4 

3-1 

Title 

General Site Location 

Site Plan - Fine-Mesh Screen Prototype 

Deck Arrangement - Fine-Mesh Screen Prototype 

Profile Arrangement - Fine-Hesh Screen Prototype 

Deck Arrangement - Fine-Mesh Screen Test Facility 

Water Quality Sampling Stations 

iV 

7 
. 

SECTION 1 

INTRODUCTION 

Tampa Electric Company (TECO) is presently planning the addition of a 

fourth generating unit at the Big Bend Station. The site is located on 

the eastern shore of Tampa Bay in North Ruskin, Florida (Figure 1-1). 

Region 4 of the U.S. Environmental Protection Agency (EPA) has expressed 

concern for losses of organisms due to the operation of the Unit No. 4 

cooling water intake. Accordingly, early in 1979, TECO requested Stone & 

Webster Engineering Corporation (S&W) to conduct an evaluation of various 

larval exclusion technologies which could be utilized in lieu of closedcycle cooling at Unit No. 4. 

Specific tasks involved in the evaluation included: 

1. The review of available intake technologies which might be applied 

to Big Bend Station to minimize losses; 

2. The selection of organism protection systems which have the 

potential for biological effectiveness and engineering reliability, 

and more detailed, site-specific evaluations of these systems; 

3. The evaluation of the need for additional studies to verify 

the effectiveness and reliability of the selected system; 

4. The performance of studies, if warranted. 

Results of Tasks 1 through 3 evaluations indicated that fine-mesh screening 

had a definite potential for effective application at Big Bend. Accordingly, 

preliminary studies were conducted at the site in the summer of 1979. 

Two separate study efforts were involved: 

1. A partial fine-mesh backfit of an existing traveling screen 

at Big Bend - Unit 1. 

2. A flume study in which various test organisms were impinged 

on a fine-mesh screen panel over a range of impingement velocities 

and durations. 

The objectives of these studies were: 

1. To determine whether available Representative Important Species 

(RIS) are capable of surviving impingement on a fine-mesh screen 

under conditions of existing screen design. 

2. To determine the relationship between specific velocity/impingement duration conditions and survival rate. 

The decision to conduct two separate studies was based on the fact that 

the use of one of the existing screens at Big Bend for a partial backfit 

evaluation would not permit changes in screen rotation speed or impingement 

velocity. With fine-mesh panels incorporated, velocities could be in 
4 

excess of 3 fps which would far exceed values that would be selected for 

a fine-screening installation. Therefore, it was believed that mortality 

estimates from the 1979 study would be higher than would be observed if 

a dual-flow screen were specifically designed to collect planktonic organisms. 

To obtain a clearer understanding of the effects of impingement on organism 

survival, the flume study was conceived to permit testing under controlled 

conditions. Velocity and impingement duration were selected as the primary 

variables of interest in the flume since, at a given power plant water 

flow requirement, the design velocity determines the number and size of 

traveling screens needed, and the acceptable upper impingement duration 

limit determines the slowest speed at which the screen can rotate. Since 

fine-mesh screens must rotate continuously, it is desirable from a maintenance 

and cost standpoint to minimize the size and number of screens and to 

operate them at the slowest speed possible. Therefore, test parameters 

were selected to cover a range of values which would have a good potential 

for protecting organisms and would also be practical to achieve at Big Bend 

Station Unit No. 4. 

The partial backfit and flume studies were designed to supply information which would serve as a basis for deciding whether to continue with 

additional fine screening studies at Big Bend in 1980. The rationale 

for making this decision was as follows: 

1. If positive results (in the form of acceptable survival values) 

are obtained from both the partial backfit and flume studies, 

proceed with additional studies in 1980. 

2. If the partial backfit study yields negative results, but flume 

survival rates are good, proceed with 1980 studies since backfit 

conditi.0n.s are very conservative. 

3. If both backfit and flume studies yield negative results, cancel. 

plans for further studies. 

The results of the 1979 studies are presented in detail in a separate 

report (Stone & Webster 1980). In summary, acceptable survival rates 

were observed in both test facilities for several of the RIS that were 

available for testing, as well as for a number of other species. Therefore, 

the decision was made to proceed with additional, large-scale investigations 

in 1980. In order to ensure the validity of the data to be obtained, 

it was further decided that the 1980 test facility would be a full-scale, 

prototype traveling screen which would be identical in every way to the 

screen which would be incorporated into an actual fine-mesh screening 

installation at Big Bend - Unit.No. 4. Design efforts began in late summer 

along with model studies which were conducted to optimize the screen’s 

hydraulic characteristics and organism collection system. Construction 

continued through the winter and was completed in time to initiate biological 

testing at the beginning of the entrainment season in early ?larch. 

This report presents a description of the test and laboratory facilities 

being utilized, all methodologies employed and a summary of results obtained 

between March 3 and April 17. These data represent roughly two-thirds 

of those collected during the first two phases of the study program, which 
ended on May 8. The third phase will begin in June and will involve a 

less intensive screen sampling schedule of one week per month through 

September, as compared to continuous sampling (five days per week) during 

Phases 1 and 2. 

A detailed description of the entire study program and the data gathered 

will be given in a confirmatory report scheduled for publication in November 

1980. 
FISHHOOK 

/>SPOIL 

4OOO 5000 
SECTION 2 

DESCRIPTION OF TEST FACILITY 

The general site plan for the test facility is shown on Figure 2-1. 

test screen is situated on a platform located in the intake channel immediThe 

ately upstream of the existing pipe bridge. 

provide access to the screen. As shown on Figure 2-1, laboratory facilities 

Stairs from the pipe bridge 

are located on the north side of the intake channel, approximately 150 ft 

from the screen facility. 

Figure 2-2 shows a more detailed plan of the screen operating deck: 

prototype screen is of the dual-flow type and incorporates all of the 

features required for fine screening. Seals are incorporated between 

screen baskets and between the baskets and the side frame to prevent the 

The 

passage of organisms through these areas. The screening medium is 0.5-mm 

square mesh made of woven-monofilament polyester. 

The screen is capable of operation at speeds up to 28 fpm. On automatic 

control, the screen runs continuously at 7 fpm; as the head differential 

across the screen reaches 4 and then 6 in., the speed increases to 14 

and 25 fpm, respectively. On manual control, the screen can be operated 

at speeds between 0 and 28 fpm. Three speeds of 7, 14, and 28 fpm were 

selected for study. These speeds correspond to maximum impingement durations of approximately ?, 4, and 2 minutes, respectively. 

Flow through the screen is supplied by an in-line pump (an adapted ship 

bow thruster pump) located under the test platform and connected directly 

to the screen via a transition section (Figure 2-3). The pump is belt-driven 

by a 250-hp motor located on the deck. Assorted pulleys allow for flow 

adjustments. Given the size of the pump and motor, flows ranging from 

8,270 to 50,000 gpm can be achieved. Since the test screen is 2 ft wide, 

these flows correspond to screen face velocities ranging from approximately 

0.25 to 1.5 fps. During the present study, pulleys were selected to achieve 

velocities of 0.5 and 1.0 fps. 

The discharge flow from the pump, composed of fine-screened water, is 

conveyed by a pipe to a location far enough downstream in the intake channel 

to prevent recirculation (Figure 2-1). At the point where the pipe passes 

under the pipe bridge, two taps are installed in the pipe to allow for 

the insertion of a flow-measuring device (for verification of pump flow 

rate and an organism sampler which can be used to determine the collection 

efficiency of the fine-mesh screen (Figure 2-4). A work platform is provided 

directly above this location to allow for the recording of pitometer measurements and the collection of biological samples. 

A floating platform is installed directly in front of the upstream (ascending) side of the test screen and is accessible by ladder. This platform 

is used for observing the location and movement of organisms as individual 

screen baskets clear the water surface. It also serves as a sampling 

location and work station from which the need for additional spray systems 

is being evaluated. 

2- 1 
The test screen incorporates shallow lifting buckets on each 2-ft wide 

screen basket which retain approximately a 1-in water depth. A low-pressure 

(10 psi) spray header, located on the ascending side of the screen, acts 

to remove organisms from the screen mesh surface and lifting buckets (Figure 2­

4). A high-pressure (55 psi) spray header is located on the descending 

side of screen to remove any remaining debris into a separate trough. 

A screenwash pump with a strainer is located on the operating deck and 

takes suction from the filtered water (bow thruster pump discharge). 

As each screen basket passes the spraywash, organisms on the mesh or in 

the lifting bucket are gently rinsed into a collection trough (Figure 2­

4). Once in the trough, the organisms flow by gravity into a primary 

collection tank from which they are drained into a secondary collection 

chamber, which also serves as the container in which the organisms are 

transported to the laboratory. 

As shown on Figure 2-1, a land-based laboratory is available for processing 

of all screen samples. Screen sampling is conducted by Stone Sr Webster 

Engineering Corporation personnel. Following collection, the samples 

are delivered to personnel from Mote Marine Laboratory (the contracted 

lab operator) for processing. The laboratory facility is designed to: 

1. Permit sorting, counting, identification, and determination 

of initial mortality of planktonic organisms. 

2. Hold selected organisms for up to 96 hours to determine latent 

mortality. 

Ambient, filtered intake water is supplied to the laboratory via a system 

of pumps, filters, and piping. A redundant water supply system was installed as a backup in the event of a system failure. This water serves as 

a water bath for maintaining ambient temperatures in a system of closed 

holding containers. However, the system is designed to allow for modification to a once-through mode of operation in which screened containers 

could be utilized to permit continuous flushing. 
. W 

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FIGURE 2-3 

PROFILE ARRANGEMENT 

FINE-MESH SCREEN PROTOTYPE 

8JG BEND STATION-UNIT 4 

TAMPA ELECTRIC COMPANY 

8 

SECTION 3 

SAMPLING PROCEDURES 

3.1 INTRODUCTION 

Sampling with the prototype screen began on March 3, 1980. In addition 

to routine screen sampling, a number of supplemental studies were included 

in the original program design'or have since been added. Procedures for 

a11 studies are presented in this section whether or not they have been 

utilized to date. However, those procedures utilized to date are described 

in greater detail. Supplemental study data will be analyzed in the near 

future and will be presented in the final report. Therefore, the procedures 

used in the supplemental studies are presented briefly here but will be 

discussed in detail in the final report. 

3.2 REPRESENTATIVE IMPORTANT SPECIES 

During the study program, emphasis has been placed on obtaining survival 

data for the RIS life stages listed below: 

Species 

Bay anchovy 

Black drum 

Silver perch 

Spotted seatrout 

Scaled sardine 

Tidewater silverside 

Stone crab (Xanthids) 

Pink shrimp 

.American oyster 

Blue crab 

Life Stage 

Egg, yolk-sac larvae, post-larvae, juveniles 

Egg, yolk-sac larvae, post-larvae, 

juveniles 

Egg, yolk-sac larvae, post-larvae, juveniles 

Egg, yolk-sac larvae, post-larvae, 

juveniles 

. Egg, yolk-sac larvae, post-larvae, 

juveniles 

Egg, yolk-sac larvae, post-larvae, 

juveniles 

Zoea1 stages, megalops 

Post-larval stages 

Larvae 

All life stages 

Th rationale for the selection f the RIS at Big Bend Station is pre ented 

in a separate report (S&W 1980). Life stage selections were based on 

the probable occurrence of each RIS in screen samples given the proposed 

operating conditions. 

3- 1 
Due to the difficulty in identifying live crab zoea, no attempt was made 

to sort and hold zoea by species. Rather, zoea were held as groups and . 

identified at the completion of the survival studies. It wa,s hoped that 

stone crab zoea would be in great enough abundance to yield meaningful 

survival data when sorted from other xanthid species. 

Other species were held as well when space and time permitted. However, 

the RIS life stages always took priority over others. The decision to 

include or exclude in the study any species not listed above was made 

each day on the basis of abundance and available time. 

3.3 PROTOTYPE SCREEN SAMPLING PROCEDURES 

Essentially the same sampling procedures were utilized during the first 

two phases of the study. As discussed previously, tests were conducted 

at screen travel speeds of 7, 14, and 28 fpm and approach flow velocities 

of 0.5 and 1.0 fps. Therefore, a complete series of tests involved screenwash collections at each of the six velocity/screen speed combinations 

in the following matrix: 

Screen Travel Speed (fpm) 

App ro a ch 

17 14 28 

0.5 I 

Within a given day, the timing of the sampling procedures was such that 

six samples could be collected and processed in the laboratory. Since 

the process of changing pulleys.to achieve test velocities required several 

hours, it was not feasible to conduct tests at both velocities within 

a single day. Therefore, the pulleys were changed at the end of every 

second day of testing at a given velocity. Within a day, two replicates 

of a one-velocity/three-screen speed portion of the matrix were obtained. 

During Phase 1, tests were conducted five days per week (up to six tests 

per day) during the daytime hours (approximately between the hours of 

0900 and 1500). At the beginning of Phase 2, the sampling strategy was 

modified to include night collection. The intent of night sampling was 

to determine whether species/life stage occurrence, abundance and/or mortality 

differ between day and night. Under this mode, sampling was conducted 

Monday through Thursday during the daytime and Thursday night between 

approximately 1900 and 2400 hrs. 

Regardless of phase or sampling strategy, the same procedures have been 

utilized in all tests to date and will be used during Phase 3. Prior 

to sampling, the bow thruster pump and screen (Figure 2-3) are set at 

the desired operating point for the specific test being conducted. The 

low- pressure spraywash is preset at 10 psi and then shut off until the 

sample is taken. Once the screen is in full operation and the movement 

of water and organisms through the test facility is in steady-state, sampling is initiated by turning on the low-pressure spray, allowing the contents 

of a predetermined number of screen baskets to be rinsed into the collection 

trough, and then shutting off the spray. The number of baskets washed 

differs for each water velocity/screen travel speed condition such that 
at each condition, the total volume of water sampled by the prototype 

screen is equivalent. 

Organisms washed into the collection trough are carried into a primary 

collection area (Figure 2-2) which contains a screened overflow (0.25 mm 

mesh). In this area, large debris (leaves, shells, ctenophores) can be 

removed as the area drains. Once the water level reaches the bottom of 

the overflow screen, the sample is concentrated to the point where it 

can be drawn down into the secondary collection and transport chamber 

where the sample is further concentrated. The drawdown is slow and gentle 

to avoid stress due to high velocities and turbulence in the drain line 

and container. 

Once the sample has been completely transferred, the container is sealed 

and transported to the land-based laboratory for sorting and latent effects 

studies. 

At the time of each sample, the following information (as a minimum) is 

recorded: date; time; air temperature; water temperature of the intake 

and collection area; tidal stage and measured height; wind direction and 

velocity; screen travel speed; screen flow velocity (nominal); spraywash 

pressure; any unusual sampling problems which occurred; and any other 

information which is deemed important. 

In addition to screenwash samples, control organisms have been collected 

and held for comparison to 96-hr mortality values experienced among organisms 

collected by the screen. During Phase 1, control organisms were collected 

one day per week, generally Monday, while in Phase 2, controls were collected 

twice weekly. 

Control organisms are collected from the intake canal by suspending a 

stationary plankton net in the canal flow (velocity c0.4 fps) for approximately five minutes. The net is then gently washed and the contents am 

transported to the laboratory where the sample is sorted for RIS life 

stages. Up to 60 of each life stage are then held in lots of five individuals 

for 96-hr. As discussed in Section 3.4, 60 organisms represents two replicate 

control groups, since a normal test group consists of 30 individuals. 

As mentioned above, all samples collected from the prototype screen are 

transferred to the land-based laboratory where they are sorted and held. 

The procedures for processing a screen sample from time of entry into 

the laboratory to the end of the latent-effects holding period are presented 

in the following section. 

3.4 LABORATORY PROCEDURES 

Once the transport container is delivered to the laboratory, the following 

procedures are carried out: 

1. The transport container is placed in a water bath and temperature 

is recorded immediately. 
t 

2. 

3. 

4. 

5. 

6. 

7. 

8. 

9. 

10. 

11. 

12. 

13. 

When RIS are abundant, the sample is gently stirred or agitated 

to obtain a homogeneous distribution of organisms and a volumetric 

subsample is drawn off. 

The primary sample is maintained in a water bath and held for 

later processing. 

The subsample (in a water bath) is sorted immediately into species/ 

life stages, concentrating on RIS species first. 

Up to five individuals of each species/life stage are placed 

in a separate container for transfer to the holding area; organisms 

are sorted to the lowest taxonomic level possible without delaying 

initiation of holding or adding incremental stress to the test 

organisms; crab zoea are held in lots of 48. 

A species/life stage sample consists of 30 organisms (48 zoea); 

therefore, once six lots of a species/life stage are counted 

and recorded, they are transferred immediately to the holding 

area for the latent effects study. 

When "stunned" organisms occur in the subsample, they are treated 

in the same manner as the live organisms, but are held as a 

separate, additional, latent-effects sample. 

Sorting continues until samples of all RIS life stages have 

been placed in holding containers; the location of all organisms 

is carefully documented. 

The remainder of the subsample is sorted by species, reco-rding 

numbers of live, stunned, and dead organisms on data sheets. 

(These data will be used to determine "initial survival.") 

If the primary sample is no longer needed, it is preserved for 

later analysis. 

If organism densities are low, several additional subsamples 

are taken in order to obtain 30 live organisms of available 

RIS for holding; in this case, only the first subsample is completely sorted for live, stunned and dead organisms; the remaining 

subsamples are drawn only Go bring the total of each RIS life 

stage to 30 (48 zoea), if possible. All organisms now in the 

holding facility are checked at 3, 6, 12, 18, 24, 36, 48, 60, 

72, 84, and 96 hr; the number live and dead at each check is 

recorded, as well as any abnormal occurrences (e.g., missing 

organisms). 

All organisms which die during the holding period are preserved 

in labeled vials. 

At the completion of the holding period, the final number of 

live and dead organisms is recorded and each group is preserved 

in a labeled vial. 
. 

14. Water quality parameters are recorded frequently during all 

holding experiments; parameters recorded include salinity, temperature, dissolved oxygen, pH, and ammonia. 

15. At the end of each latent-effects test, all vials are rechecked 

and all organisms are identified (to species, if possible), 

categorized to life stage and counted. 

These procedures have functioned very effectively in permitting an accurate 

accounting of most organisms from collection through final identification. 

Data gathered during each stage of the latent-effects studies are recorded 

on various data sheets which are subjected to frequent quality assurance 

checks. A detailed description of the data handling procedures employed 

is given in the appendix to this report. 

3.5 SUPPLEMENTAL STUDIES 

In addition to the prototype screen sampling efforts, several supplemental 

studies are being, or will be, conducted to gather information which will 

be used in the overall evaluation of the potential effectiveness of finemesh screens at Big Bend Station. Each study is described individually 

below. 

3.5.1 Spraywash Efficiency Study 

Since the spraywash system being incorporated into the prototype screen 

represents a new design, the effi.ciency’of the system in washing organisms 

into the collection trough is being investigated. Samples are collected 

by screening the water exiting the debris trough on the high-pressure 

spraywash side of the screen while the low-pressure spraywash is in operation 

(refer to Figure 2-2). In this way, the number of organisms removed by 

the low-pressure spray can be directly compared to the number carried 

over to the high-pressure spray and the low-pressure spraywash efficiency 

can be calculated. If the low-pressure spray is effectively cleaning 

the screen mesh and lifting buckets, relatively few organisms should be 

recovered in the high-pressure spraywash water. Naturally, the speed 

of the screen will influence cleaning efficiency, with efficiency expected 

to decrease as speed increases. Therefore, samples are taken at all three 

travel speeds (7, 14, and 28 fpm). 

Each sample is concentrated by washing down the screened collection box 

and is then preserved for later analysis by laboratory personnel. Laboratory 

analysis consists of enumeration, identification to species or lowest 

feasible taxonomic level, determination of life stage and size measurements 

(fish larvae only). 

3.5.2 Plankton Net Sampling 

Plankton net samples collected adjacent to the prototype screen structure 

will be used to compare the relative meroplankton impingement rates at 

the various screen test conditions with the abundance of meroplanktonic 
organisms measured in the immediate vicinity of the prototype structure. 

Samples are collected using the same techniques employed in the 1979 meroplankton study (Mote Marine Laboratory, 1980). Four replicate samples 

are collected on one day during each week of screen s:ampling at the time 

that screen samples are collected. Samples are preserved for later processing. Laboratory analysis for RIS will consist of enumeration, identification 

to species or lowest feasible taxonomic level, determination of life stage, 

and size measurement (fish larvae only). 

3.5.3 Prototype Screening Efficiency 

To determine the efficiency of the prototype screen in preventing the 

passage of organisms either through the 0.5-mm mesh or the various sealed 

areas in the screen assembly, samples of the screened water will be taken 

during Phase 3. Samples will be preserved and processed in the laboratory. 

Laboratory analysis will consist of enumeration, identification to species 

or lowest feasible taxonomic level, determination of life stage, and size 

measurements. 

Samples will be collected from the sample pump discharge (refer to Figure 2­

4) in two conical plankton nets submerged in tanks. Results obtained 

will be used to establish the need for additional sampling or, possibly, 

modifications to the screen. The Phase 3 samples will be processed immediately 

after collection and the data will be examined to determine whether major 

"leaks" exist in the screening assembly which must be found and sealed 

prior to use on a full-scale basis at a power plant intake. 

3.5.4 Air Exposure Studies 

Past studies have shown that some organisms, particularly in their early 

life stages, are very sensitive to air exposure. Since the prototype 

screen has the potential for exposing impinged organisms to the air for 

short periods of &.me (several minutes), it is desirable to determine 

how this additional stress factor might influence overall mortality resulting from collection and removal from the fine-mesh screening. Accordingly, 

provisions were made to conduct on-site studies on species showing low 

survival. During such studies, individuals would be exposed to the air 

for up to three minutes, followed by 96-hr mortality determinations. 

Past research at Big Bend indicates that Anchoa mitchilli may be particularly 

sensitive to air exposure. Since the anchovy is abundant at Big Bend, 

it was planned that emphasis would be placed on testing this species. 

To date, very high initial mortality observed among anchovy larvae collected 

by the prototype screen is not believed to be a function of air exposure, 

but rather the impingement and removal process. This conclusion is based 

on careful observation of the position and condition of these organisms 

as they clear the water surface during screen rotation. Under the condi­

--. tions tested, anchovy larvae have been observed to be dead or dying as 

the screen panels enter the air. Therefore, it was not deemed necessary 

to conduct air exposure studies during Phases 1 and 2. 

3-6 
Should survival of anchovy larvae improve during Phase 3, such that air 

exposure appears to be affecting mortality, studies will be conducted. 

Testing will consist of placing small lots of organisms in holding containers 

with screened bottoms, lifting the containers out of the water for different 

periods of time (from ten seconds to three minutes), returning them.to 

the water, and monitoring mortality for 96 hr. 

The data obtained from this study effort would be used to determine the 

need for an additional low-pressure spraywash. To minimize air exposure, 

the wash would be located at a point just above mean high water and would 

be designed to rinse impinged (exposed) organisms from the screen mesh 

into the water-filled lifting bucket. In this way, the organisms would 

now remain in water while traveling upward to the spraywash located at 

operating deck elevation. 

3.5.5 Organism Return System Investigations 

3.5.5.1 Introduction 

A critical component of an organism protection device is the design, operation, and discharge location of the organism return system. Should finemesh screens be employed at Big Bend Station, a trough will be utilized 

to transport collected organisms for discharge at one of two possible 

locations: (1) the presently unused canal just. north of, and parallel 

to, the intake canal, and (2) off of the breakwater south of Fish Hook 

Spoil (Figure 3-1). At either location, two concerns exist: can the 

RIS 0,rganisrns of concern at Big Bend be transported in a trough without 

undue stress, and will differences in.water quality between the intake 

and the discharge location adversely affect the survival potential of 

returned organisms. 

To address these concerns, SStW initiated a number of additional studies 

in May 1980. These studies will continue until September and will be 

discussed in detail in the final study report. Therefore, the following 

discussions present a brief summary of each task associated with the organisms 

return system studies. 

3.5.5.2 Flume Study 

In order to evaluate the effect of travel through a return trough on organism 

survival, studies will be conducted in a circular flume. The flume will 

measure 12 in. deep by 9 in. wide and will have an outer diameter of 8.3 ft. 

A central motor drive unit will propel paddles around the flume thereby 

moving the water contained therein. The paddles will seal tightly with 

the flume walls and bottom to prevent leakage. 

Tests will be conducted by placing individual groups of RIS-life stages 

into the flume and allowing them to circulate at velocities of 2 fps for 

1 hr. This velocity is considered sufficiently high to move organisms 

rapidly to the release site and low enough to minimize damage due to turbulence and abrasion. Test organisms will be obtained from the prototype 
a 

screen. Thus, they will have experienced the entire process of impingement, removal and transport. The results can then be compared to the 

results obtained from the prototype screen to determine the incremental 

stresses of transport. Control organisms collected from the prototype 

screen will also be placed in the flume and collected to determine whether 

the flume testing procedure contributes substantially to any mortality 

observed. 

Following each test run, the organisms will be removed from the flume 

by draining the water into a screened collection box. The organisms will 

then be enumerated as live, stunned, and dead and held for 96 hr to determine 

latent mortality. Holding procedures will be identical to those used 

in the prototype screen evaluation (Section 3.4). 

3.5.5.3 Water Quality Measurements 

Assuming that the organisms of interest at Big Bend can survive passage 

through relatively a long trough, a final question remains relative to 

the effects of water quality on ultimate survival. Of the two proposed 

discharge locations, the preferred location has been identified as the 

canal (Figure 3-1) which is parallel to, and immediately north of, the 

power plant intake canal (PIC). This location would have a much shorter 

travel distance and would therefore return the organisms quickly with 

less potential for transport stresses. Due to differences in flu-shing 

rates, it is possible that this proposed organism return canal (ORC) could 

differ in water quality from the PIC to the extent that organism survival 

would be affected. In order to identify any important differences in 

water quality between the ORC and the PIC, a series of water quality, 

hydrographic and plankton samples will be collected during Phase 3 (May 

through September). The other possible discharge location off of the 

breakwater south of Fish Hook Spoil is an area of ambient bay conditions 

and is deemed to have acceptable water quality should it be used. Three 

sampling stations have been established: one in the PIC and two in the 

ORC (Figure 3-1). The frequency of sampling is determined by the tasks, 

as outlined below: 

a. Water Quality Sampling: DO, pH, salinity and temperature will 

be recorded at three depths (surface, mid-depth, bottom) at 

each station using a YSI DO meter, a YSI S-C-T meter and an 

Orion pH meter. Sampling will occur on a weekly basis in the 

first week of May and terminate in the third week of September. 

b. Other Water Quality Parameters: NO3, N02, NH3-N, Organic N, 

Ortho-P, Organic P, chlorophyll "a" and phaeophytin "a", BODS, 

TSS, oil and grease, metals (Cd, Ni, Zn, Hg, Hn, Cr, Cu, Fe, 

Pb), organochlorine pesticides and fecal coliforms will be sampled 

at each station at two depths (surface and bottom). Samples 

will be taken once per month and one time 24 hr after a heavy 

rainfall. 

3-8 
. 

3.5.5.4 Plankton Sampling 

To aid in the determination of the suitability of ORC water for sustaining 

the RIS returned from a fine screening installation, phytoplankton, zooplankton, and meroplankton samples will be collected at each water quality 

station once per month from May through September. Four replicates will 

be collected at each station for each sample. 

Phytoplankton samples will be collected with a 1 gal water sampler from 

about 0.5 ft below the water surface at each station (four samples per 

station). The samples will be preserved in the field, returned to the 

laboratory and processed in the following manner: 

A minimum of two subsamples will be analyzed from each sample, the 

subsample will be pipetted into a 0.12 m Palmer nannoplankton counting 

chamber where cells will be allowed to settle before examination 

under a microscope. Large phytoplankton will be enumerated and identified at 200X magnification and small diatoms and phytoflagellates 

at 400X magnification. One or two diameters of the counting chamber 

will be scanned until approximately 150 to 200 cells are counted 

(filamentous blue-green algae, however, are counted as trichomes 

and not cells). Identification will be carried to the species level 

for large cells and to the lowest practical level for small diatoms 

and phytoflagellates. 

The total concentrations of cells in the subsample will be calculated 

by: 

where 

C = total cell numbers (cells ml-1) 

N = number of cells counted 

V = volume examined (ml) 

The total concentration of cells in the sample will be estimated 

from the average of the subsample concentrations. 

Zooplankton samples (four at each station) will be collected with a 0.5 m 

diameter, 80 micron mesh net. At each station, the net will be allowed 

to sink approximately 2 m and will then be towed to near the surface. 

A General Oceanic 2030 flowmeter will be mounted on the mouth of the net 

to provide an estimate of the water volume sampled. Upon retrieval, the 

net will be washed down and the samples in the cod-end will be preserved 

in 10 percent buffered formalin. 

Laboratory analysis of the zooplankton samples will be conducted in the 

following manner. A 5 or 10 ml aliquot (depending on the apparent abundance 

of zooplankton in the sample) will be withdrawn from each replicate sample 

and placed in a gridded petri dish. All animals contained in the aliquot 

will be enumerated and identified to the lowest practical taxonomic level 

under a dissecting microscope. If less than 200 animals are found in 

the initial aliquot, additional aliquots will be withdrawn and sorted 

3-9 
until at least 200 organisms are found. In some cases, due to low numbers 

of organisms, the entire sample will be sorted. 

The number of organisms per m3 at each station will be calculated from 

the mean number of organisms of each species from the four replicates. 

Meroplankton samples will follow the methods of the 1979 Aquatic Ecology 

Program (Mote Marine Laboratory 1980). 

3.5.5.5 Organism Survival Studies 

Organism survival studies using ORC water in holding containers will be 

conducted during one week each per month from June through September. 

Organisms collected from the prototype screen will be sorted into batches 

of 30 (lots of five) and held in ORC water for 96 hr. Procedures will 

be as outlined in Section 3.4; however, all samples will be collected 

in one day. In addition, control organisms collected from the prototype 

screen will be held in intake canal water for comparison. of latent survival. 

3.5.5'.6 Hydrodynamic Evaluation 

Organisms which have been returned to the water body are once again subjected 

to the processes of ambient dispersion. A prediction and assessment of 

probable movement, especially the likelihood of reentrainment in the intake 

flow, is being sought in order to contribute to the evaluation of candidate 

release points. 
n 4 

ti 

FISH HOOK 

spot L-
. 

SECTION 4 

RESULTS TO DATE 

This section presents the results of an analysis of available data collected 

during Phase 1 and part of Phase 2. The data represent initial and latent 

survivorship of organisms which have been collected by the fine-mesh prototype 

screen and control organisms not subjected to impingement stress. The 

results of initial survival studies include tests conducted up to May 7, 

1980 and the latent survival data include results of tests conducted up 

to April 17, 1980. 

The proportion of organisms which were alive when the sample was brought 

into the laboratory was determined from data on the species/life stages 

presented in Table 4-1. In order to have sufficient observations for 

analysis, less abundant species were combined to form the following groups: 

sciaenids, clupeids, gobies, decapods (minus the stone crab). The bay 

anchovy and stone crab were analyzed separately. 

Table 4-2 presents the mean initial survivorship and the standard deviation 

for the organism groups. These data indicate that the invertebrates had 

the highest survival, most often in excess of 90 percent. The fragile 

fish, such as the bay anchovy (Anchoa mitchilli), had low survivorship, 

as expected for larvae and post-larvae. 

To provide an indication of the source of variability in these survivorship 

estimate, an analysis of variance was conducted according to the experimental 

design discussed in Section 3.3. All analyses of variance were conducted 

by life stage on the taxanomic groupings identified in Table 4.2. 

Table 4-3 presents the results of the analyses of variance. In general, 

few of the analyses revealed significant (p< 0.05) effects for screen 

speed, approach velocity or their interactions. An inspection of the 

means which are significantly different suggests that the results between 

species are confused. For example, the bay anchovy egg interaction between 

screen speed and approach velocity reveals higher survivorship at 1.0 fps 

than 0.5 fps for screen speeds of 7 fpm and 28 fpm, and the reverse pattern 

for 14 fpm. Since this pattern is contrary to expectation and not confirmed 

by the other species, the result is probably a function of the samples 

analyzed to date and not a general trend. 

Therefore, in view of the few analyses which revealed significant screen 

speed or approach velocity effects and the unexpected nature of some of 

the differences, it appears that, in general, the initial survivability 

is not greatly affected by screen speeds from 7 to 28 fpm or approach 

velocities from 0.5 to 1.0 fps. 

The latent survivorship of those organisms which were initially alive 

was studied in the holding experiments in the laboratory. The proportion 

of organisms which were alive at 48 hr and 96 hr was used as an fndex 

of latent survival. 
Species/life stages which were used as a basis to determine 48 and 96 hr 

latent survivorship are presented in Table 4-4 and 4-5, respectively. 

As with the initial survivorship estimates, these data were collapsed 

into similar taxonomic groups for analysis. The mean and standard deviation 

for the 48 and 96 hr survivorship values are presented in Tables 4-6 and 

4-7, respectively. The results indicate that survivorship is 'taxa-and 

life stage-specific, as is the relationship between 48 and 96 hr values. 

These values should be viewed in connection with control survivorship 

presented later in the results. 

The hatchability of eggs during the holding experiment is an index of 

' the viability of the eggs. Since the development time of eggs for many 

of the species tested is quite rapid, nearly all eggs should hatch prior 

to 96 hr. Therefore, the proportion of eggs which hatched during the 

holding period is presented in Table 4-8. 

An analysis of variance procedure, of the same design as -the initial survival 

analysis, was employed to investigate the sources of variation in latent 

survivorship. The results of analyses of variance using 48 hr survivorship 'as the dependent variable are presented in Table 4-9, while the results 

using 96 hr survivorship as the dependent variable are presented in Table 4-10. 

The results of the analyses of variance for latent survivorship were similar 

to that of the initial survivorships. Few independent variables for a 

few of the groups were found to be significant (p 0.05). However, the 

fact that for most analyses these variables did not consistently explain 

a significant amount of variability, suggests that.these variables within 

the range of values tested do not significantly alter the survivorship 

of organisms. 

To date, the results of three control samples were available and the survivorship of control organisms which had not experienced the fine-mesh screen 

system are presented in Table 4-11. These survivorship values indicate 

that natural mortality, not associated with stresses resulting from the 

collection and holding procedures, is a contributing factor to the mortalities 

observed among organisms collected by the fine-mesh screen. 
TABLE 4-1 

TAXA/LIFE STAGES USED IN INITIAL SURVIVORSHIP ANALYSIS 

Taxa 

Anchoa mitchilli 

Bairdiella chrysura 

Cynoscion arenarius 

Pogonias cromis 

Sciaenidae 

Gobiosoma robustum 

Microgobius gulosus 

Microgobius sp. 

C 1upeidae 

Harengula jaguana 

Menippe mercenaria 

Caridea 

Common Name 

bay anchovy 

silver perch 

sand seatrout 

black drum 

unidentified drums 

code goby 

clown goby 

unidentified goby 

Life Stage 

eggs 

larvae 

Postlarvae 

post1a rvae 

postlarvae 

postlarvae 

eggs 

larvae 

postlarvae 

postlarvae 

po st1arvae 

po s't1arvae 

unidentified herrings eggs 

scaled sardine eggs 

stone crab zoea (stage 1) 

unidentified caridean zoea (unstaged) 

shrimp 

Sheet 1 of 2 

3/ 
Taxa 

Upogebia affinis 

Brachyuran 

Decapoda 

"Shrimp" 

Paguridae 

TABLE 4-1 (Cont'd) 

Common Name Life Stage 

mud shrimp zoea (unstaged) 

unidentified true crab zoea (unstaged) 

mega lops 

unidentified decapods zoea (unstaged) 

unidentified shrimp- zoea (unstaged) 

like decapods 

unidentified hermit zoea (unstaged) 

crabs 

Sheet 2 of 2 3% 
a 

cr)

N 

0 

0 r- 0 

ln m U 0 0 N 

0 0 0 

Q 

0 

Ln 

ri 

N 

4 

0 0 b 

0 0 0 

GOY n 

C 

0 

I m r i ri 

e 

m 

s4 

U 

aJ 

c 

C 

JJ 

u3 
aJ 

m v1 > 

CD Lc M m aJ ri 

h 

3 

QJ 

m 

?, m m 4 4 

L) il 

In Lo 

0 0 

a 3, a 

a 

m 

5 

n 

n 

ri 

al 

Eo 

m 

Cr 

VI 

v 

m m 0) aJ 

0 0 

N N 

n 

d 

ri 

m 

v 

V 

QJ

c 

3 

4J 

rn 
TABLE 4-5 

Taxa/Life Stages Used In 96 Hour Latent Survivorship Analysis 

Taxa Common Name Life Stage 

Anchoa mitchilli bay anchovy larvae 

po s t1a rvae 

hatched larvae 

Bairdiella chrysura silver perch postlarvae 

Cynoscion arenarius sand seatrout postlarvae 

Pogonias cromis black drum po s tla rva e 

Sciaenidae unidentified drums larvae 

postlarvae 

hatched larvae 

Gobiosoma robustun code goby postlarvae 

Microgobius gulosus clown goby post la rvae 

C lupeida e unidentified herrings hatched larvae 

Menippe mercena r ia stone crab zoea (stage 1). 

Caridea unidentified caridean zoea (unstaged) 

shrimp 

Upogebia af f inis mud shrimp zoea (unstaged) 

Bra chyur a unidentified true crabs zoea (unstaged) 

mega 1op s 

Decapoda unidentified decapods zoea (unstaged) 

"Shrimp" unidentified shrimp- zoea (unstaged) 

like decapods 

Paguri da e unidentified hermit zoea (unstaged) 

crabs 
4 

Species 

Sciaenidae 

Clupeida e 

Bay anchovy 

Stone crab 

Decapods (all) 

TABLE 4-6 

48 HOUR LATENT SURVIVORSHIP 

Life Stage 

hatched larvae 

eggs 

larvae 

postlarvae 

adult 

hatched larvae 

post larva e 

hatched larvae 

eggs 

larvae 

postlarvae 

zoea (stage 1) 

(stage 2) 

zoea (combined) 

mega lops 

Proportion Alive 

Standard 

N Mean Deviation -

85 0 0.844 0.325 

95 0.067 0.225 

31 0.228 0.399 

133 0.890 0.282 

12 1 0 

74 0.951 0.209 

10 1 0 

945 0.612 0.244 

159 0.059 0.201 

8 0.125 0.354 

10 0 - 700 0.483 

63 0.965 0.148 

11 1 0 

433 0.955 0.192 

88 0 - 985 0.112 
TABLE 4-7 

Species 

Sciaenidae 

Clup e ida e 

Bay anchovy 

Stone crab 

Decapods (all) 

96 HOUR LATENT 

Life Stage 

hatched larvae 

eggs 

larvae 

postlarvae 

hatched larvae 

postlarvae 

hatched larvae 

larvae 

postlarvae 

zoea (stage 1) 

zoea (stage 2) 

zoea (unstaged) 

megalops 

3 

SURVIVORSHIP 

Proportion Alive 

-N Mean 

850 0.788 

95 0 

31 0.183 

133 0.798 

74 0.851 

10 . 0.900 

945 0.432 

Standard 

Deviation 

0.372 

0 

0.376 

0.342 

0.323 

0.316 

0.225 

8 0.125 ’ 0.354 

10 0.433 0.410 

63 0.894 0.248 

11 0.727 0.467 

433 0.736 0.415 

88 0.908 0.272 
TABLE 4-8 

Hatchability of Eggs During Holding Experiments 

SDecies ProDortion of EPPS Hatched

Bay anchovy 

Clupeidae unidentified 

Sciaenidae unidentified 

0.865 

0.588 

0.842 
TABLE 4-9 

Analysis of Variance for 48 Hour Latent Survival 

Species Life Stage 

Sciaenidae hatched larvae 

eggs 

larvae 

po s tla rvae 

C lupeida e hatched larvae 

Bay anchovy hatched larvae 

eggs 

Stone crab zoea (stage 1) 

Decapods (all) zoea (combined) 

megalop s 

F Value 

Screen App roa ch 

Speed Vel0 ci ty Interaction 

0.33 4.69" 0.07 

3.09 0.31 0.39 

0.28 1-10 0.36 

1.38 3.79 2.64 

0 0.53 0 

0:52 86. 7 1$+ 0.60 

5 35'"' 2.61 6.21%+; 

0.30 1.66 1.01 

I

2.93 3.71 2.38 L 

1.44 2.92 1.44. 
mr-rn I -,. a IAHU 4-IU 

Analysis of Variance 

Species Life Stage 

Sciaenidae hatched larvae 

postlarvae 

Clupeida e hatched larvae 

Bay anchovy hatched larvae 

Stone crab zoea (stage 1) 

Decapods (all) zoea (combined) .. . 

mega lops 

for 96 Hour Latent Survival 

F Value 

Screen Appro a ch No. ObserSpeed Velocity Interaction vations 

1.08 1.60 0.19 849 

2.45 1.82 0.91 133 

0.88 0.38 0.02 74 

4.07" 49.825-2 0.17 945 

0.03 0.04 0.29 63 

3 .66;:- 13.5 1;';;: 2.96 433 

0.71 0.06 1.79 88 
,-

I 

I 

Ill 0 t- m 

m m U 0 

0 0 0 0 0 0 

-0 -000 -00 ­ 0 0 0 0 0 0 

Q 

U 

iia 

0 

0 

Lc 

JA 

a 

0 

U 

(.

c 

0 

r( 

r, 

2 i 

V 

r) U 0 

3 - a 

U X 

0

: d c) QI * 

U U U U 6 0 ­ z i i i 0 a0 

ut w 0 a w .)

d r( 4

i;' Q '0 

(I U U d A A 

LI V u .) L) J 

0 a a a a c 

a 

La 
.. 

i 

SECTION 5 

CONCLUSIONS 

The results presented in Section 4 indicate that fine-mesh screening. 

is a viable alternative for removing organisms from the circulating water 

flow at Big Bend Station and returning them safely to their natural environment. The 0.5-mm mesh used on the prototype screen has demonstrated its 

capacity for effectively retaining the RIS life stages under study; therefore, such a fine-mesh system would ensure the protection of the RIS at Big 

Bend. 

Results of testing to date indicate that initial and latent survival are speciesand life stage-dependent, with invertebrates showing the highest survival and 

bay anchovy larvae showing the lowest survival. Such low survival rates for 

anchovy larvae were anticipated given the very fragile nature of this species. 

Initial and latent survival of fish eggs was relatively high, particularly 

among Sciaenids. No attempt was made to adjust latent survival values for 

control mortality (Table 4-11]; however, by comparing test and control mortalities, it is evident that much of the mortality observed among test 

organisms is a reflection of natural mortality and handling stress. The 

process of collecting, concentrating and sorting organisms removed from the 

prototype screen is certainly a contributing factor in mortality that would 

not be as severe in a full-scale, fine-mesh screen facility. This fact, and 

consideration of control mortalities, leads to the conclusion that survival 

values at Big Bend could be higher than those observed in studies to date. 

Overall survival values for invertebrates, specifically the stone crab, should 

approach 100 percent. 

Although few fish and invertebrate juveniles and adults are impinged at the 

existing Big Bend Station, a fine-mesh screen intake system should greatly 

alleviate impingement and would reduce themortality of those organisms which 

would Secome impinged since they are presently all killed after being collected 

from the screen. Observations in 1979 and 1980 of the survival of the few 

juvenile and adult organisms collected by the fine-mesh screen suggest that 

they are not affected by the impingement and removal process. These organisms 

can be returned to Tampa Bay without significant effect of the overall biological integrity of the bay system. 

On the basis of existing data, it would appear that installation of fine-mesh 

screening on Big Bend Units 3 and 4 would resultsinentrainment losses less 

than those presently experienced with Units 1 to 3 without dilution pumping. 

Further studies throughout the summer months will provide additional data to 

refine these preliminary results. Additionally species/life stages of the RIS 

will be studied in the summer months; additional control data will be collected; 

verification of filtration and spray wash efficiencies will be made; and return 

flume survival will be estimated. In addition, the remainder of the study data 

gathered this spring but not included in this report will be added to the data 

base and subjected to further analyses. 

5-1 
REFERENCES 

Mote Marine Laboratory, 1980. 1979 Aquatic Ecology Program, Big Bend 

Power Station, Tampa, Florida. Final Report (April 21, 1980). 

Stone SI Webster Engineering Corporation, 1980. Studies To Develop An 

Intake Design For Reducing Entrainment Losses, Unit No. 4-Big Bend 

Station. Prepared For Tampa E1ectri.c Company (February 1980). 
APPENDIX 

PROTOTYPE FINE-MESH SCREEN EVALUATION 

BIOLOGICAL STUDIES 

PROGRESS REPORT 

BY 

MOTE MARINE LABORATORY 
PROTOTYPE FINE MESH SCREEN 

EVALUATION 

BIOLOGICAL STUDIES 

PROGRESS REPORT 

Reference : ESSOW No. 12408.64-WOO3V 

J.O. No. 12408.04 

Submitted to: Stone and Webster Engineering Corporation 

P.O. Box 2325 

Eioston, Massachusetts 02107 

Attn: Mr. Curtis R. Young 

Submitted by: .. 

Selvakmaran Mahadevan, Ph.D. 

Staff Scientist/Project Manager 

Mote Marine Laboratory 

1600 City Island Park 

Sarasota, Florida 33577 

March 15, 1980 
I . . 

TABLE OF CONTENTS 

1 . INTRODUCTION ............................................... 1 

11 . PROGRESS TO DATE ........................................... 1' 

a) Facilities ........................................... 1 

b) Prelininary Studies .................................. 2 

c) External ExFertise ................................... 3 

I11 . STANDARD OPERATING PROCEDURES .............................. 3 

IV . RECOMMENDATIONS ............................................ 9 

V . REQUEST FOR APPROVALS ...................................... 10 

APENDIX - EXAMPLES OF PROJECT DOCUI+EWl"TION.AND RECORDS 
. 

I. INTRODUCTION 

The Prototype Fine Mesh Screen Evaluation Biological studies were 

begun on February 1, 1980. The preliminary phase (February 1-29, 1980) 

addressed some of the potential problems that may arise in the regular 

testing program and conducted short-term studies on feeding requirements, 

best methods for observation and sorting, and the suitability of a closed 

system for holding organisms. The phase also physically set up the holding 

facility and its once-through seawater system, and conducted tests to debug the seawater system. Phase l (March 1-31, 1980) was designated as 

a shakedown phase. This phase requires intensive sampling as part of 

a preliminary screen evaluation. Data obtained will serve as a basis 

for finalizing test parameters and procedures to be used in phases 2 and 

3 (Regular Testing Program; Phase 2: April 1 to May 15, 1980; phase 3: 

June 1 to September 15, 1980). This report provides a summary of progress 

to date on the preliminary phase and part of phase 1. It provides a 

description of the Standard Operating Procedures (SOP) to be used in 

the Regular Testing Program, discusses findings or' the preliminary phase 

and provides a summary of the recommendations of our expert consultants to 

date on the sorting and holding procedures. sased on our findings and 

the recommendations of the consultants, we request approvals .-_ for certain

methods and procedures that are not specifically addressed in the ESSOW 

for the study. 

11. ?RCGilESS TO DATE 

a) Facilities 

As specifiec! in the ESSOK,.a laboratory facility has been set-up 

at the site (Big Bend). The laboratory is located in two trailers: 

Trailer 1 (Haldinc Facility): This 60' x 12' trailer is outfitted 

with a once-throuqh seawater system. The seawater is distributed.to 

23 tables. Nineteen of these tables are "holding" tables with a capability 

of holding approximately 8000 organisms at one time. Holding containers 

are 500 ml. jars and tackle box trays. Four of these tables are "sorting" 

tables (space for a total of eight sorters) with glass windows and 

1 
underneath-the-table liahtina. Seawater is withdrawn from the intake 

canal and piped to a tank via two filters (a dual svstem exists from 

intake to the tank for DurDoses of a back-uD svsteml. From the tank, 

the seawater is piped to the tables through three lines. Each table 

has an individual valve for water flow control. The holding facility 

also has two worktables where microscopes are available. Four carts in 

the facility serve as observation aids (carts lighted from underneath 

with glass windows on top) and as water quality monitors tray. 

Trailer 2 (office): This 48' x 12' trailer serves as the office 

trailer. It contains office space for the section supervisors (Comp 

and Phillips), work-space �or the technicians (including microscope 

area, a copier, files and a culture room where algae and rotifers are 

grown). 

The laboratory facilities have been inspected by the followincj 

Stone and Webster personnel: Messrs. E.?. Taft, C.R. Young and R. 

Felts. The seawater system has been continuously operating since 

February 29, 1980 and no problems have been encountered. The laboratory 

design was as outlined in the proposal; no variations were made. To 

date, samples to about 1/3 capacity of the holding facility are being 

processed. Approximately 4-5 spaces in the sorting area are being 

utilized. 

b) Preliminzry Studies 

All reports culminating from the preliminary studies have Seen 

forwarded to Stone and Webster personnel, C.R. Young and Z.P. Taft 

(please see letter of transmittal dated 2/29/80 and accompanyin5 

enclosures). Since those reports, we have held orcanisms (collected 

by d plankton net and from the screen) at the site (holding facility). 

Data sheets have Seen transmitted to Yr. E.?. Taft. These combined 

studies re-inforced our earlier findings that .organisins could be helc! 

in close6 containers. 

2 
1. 

2. 

3. 

4. 

5. 

C) 

Summarizing the findings to date: 

Feeding is required for larvae beyond the eye pigmentation stage. 

High survival rates were evident even in closed containers. 

Mortality stains are too species-specific and are difficult to 

be retained in the preservation stage. 

Various methods of observation of live/dead organisms were tested 

and guidelines for best methods in sorting and observing were drawn. 

Control organisms can be successfully collected with plankton nets. 

External Expertise 

Dr. Sheldon Dobkin and Mr. Keith Taniguichi visited the holding 

facility and provided input in the sorting an6 holding of organisms. 

Letters summarizing their suggestions were sent to Messrs. E.P. Taft and 

C.R. Young (dated 2/29/80 and 3/11/80). Both felt that closed systems 

(500 ml containers or tackle box trays) would be adequate if the orcjanisms 

densities are low and if water change is accomplished at least once 

during the 96 hour period [preferably at the 48-hour observation check). 

Both felt that feeding is necessary if the organisms are held �or 96 

. hours. Both speculated that 48 hours would be a sufficiently lonq 

period for estimating latent mortality. ’ Both experts provided various 

suggestions to our skaff for efficient sorting and holding techniques. 

111. STANDARD OPERATING PROCEDURES 

The Standard Operating Procedures (SOP) �or the program are discussed below. 

FIELD PROCEDU-XES 

Procedures have Seen established for the conduct and documentation 

of activities which take place in the field.. Implementation of the 

procedures is the direct responsibility of the Section Supervisor Lho 

will be in the field during most if not 211 sampling tiips. In additicn 

to periociic observation of sampling activities, the proqram manager will 

review field documentation to assure that all required information 

has been provided, that all procedures were followed and that proper signatures have been obtained. 

Procedures for the collection of meroplankton RIS in the intake 

canal were described in the Scope of Work of this.project. 

Tows are taken ss described in the Scope of Work for this project. 

A 4.8 n beam is mounted across the boat to al.low the nets to fish 
outside the prop wash as much as possible. The nets are released 

simultaneously, allowed to sink to near the bottom, and pulled from 

that position so as to travel obliquely through the water column. 

The nets are then recovered simultaneously over the same side of the 

boat. Flowmeter readings are taken, checked, and entered in the logbook. The nets are rinsed into the cod end, the cod jar is removed, 

and an internal label and formaldehyde are added. The jar is capped, 

shaken, another jar is screwed onto the net, and the procedure repeated. 

Physical data are taken upon arrival at the station. Station 

depth is taken by a marked line at the Hydrolab which is lowered 

vertically and the depth read directly. The line is marked in 0.5 m 

intervals. From the depth data, mid and bottom depths are found for 

measurement of hydrographic data. Data are taken by one person, with 

any questionable data retaken by another person after all readings 

for all depths have been completed. 

Plankton nets are thoroughly rinsed after each tow to minimize 

cumulative net clogging. Nets are checked, for tears after every 

sampling trip, and machine washed in cold water whenever ricroscopic 

examination shows any change in pore size due to clogging. If necessary, 

minor repairs to the nets are performe2 in the field. 

All samples are preserved in the field and are doubly labeled, 

i.e., both internal and external labels for sample containers. The 

labels identify the sample by date, station, gear, tine of sampling, 

and tow number, and are initialed by the Section Supervisor. Samples 

are returned to the laboratory immediately after completion of a 

sampling trip. 

All data are recorded by one person of the field crex and checked 

and signed by another member of the field crew. 

Spraywash and screen efficiency samp1e.s are collected by Stone and 

Webster personnel and given to a section supervisor at the holding' 

facility. The seccion supervisor records collection data on internal 

and external labels of a quart jar. The sample is preserved with 

buffered formaldehyde in the quart jar and transported to WIL-Sarasota 

laboratory. 

4 
. LABORATORY PROCEDURES 

A. Net and Sprsywash/Screen Efficiencv Samples: 

Plankton net samples and spraywash/screen efficiency samples are 

processed in the laboratory in a manner that each sample or subsample 

is traceable to its collection and that all data reported for these 

portions of the study are both valid and documented- Procedures are 

as follows: 

Each aliquot is examined twice, with agitation between examinations. 

To check for sorting and identification efficiency, at least 5 percent 

of the samples are re-sorted and verified by a qualified individual 

other than the person who did the initial sorting and identification. 

Sorting efficiency is maintained above 95 percent for all RIS. 

Identification of larval specimens is made through use of standard 

literature sources for each RIS. Voucher specimens are referred to 

appropriate External Consultants for identification/confirmation, 

as necessary. A reference collection of taxonomically confirmed 

species is maintained. 

Bench data sheets (Data Sheet No. 4 - Appendix) contain all field 

data for a sample including the volume sampled, as well as sorting data 

and individual measurements. Three copies of the bench sheets are made. 

One copy is transmitted to Stone and Webster, the original is retainei 

by the Project Coordinator, one copy is placed in the Archives at .WL, and 

one copy is placed in the Section Supervisor's (Blanchet) files. 

Subsampling is accomplished by use of a 10 ml capacity Tipet 

dispenser or 5 ml pipet for numerous eggs. The sample is'placed in 

an appropriately sized Erlenmeyer flask after the volume is adjusted 

to allow efficient sorting. The sample is agitated thoroughly, and 

aliquots are drawn off into a gridded petri dish. Depending on the 

density of plankton, up to four aliquots may be sorted at one time. 

Subsamples dre sorted consistently, that is, they are completely 

sorted for any XIS for which less than 100'specimens have been picked 

from the sanple. The density/lOOrn 3 of any species is then calculable 

by comparing the volume of sample examined (E)to pick out any number 

of specimens (NS), to the total volume of the sample (TV) and the volume 

of water filtered (VF) , to give the density of the species (SD): 

All samples are stored until the ?reject is completed. All 

sorted specimens will be cataloguer3 and similarly maintained, except for 
voucher specimens which will be placed in the permanent MNL reference 

collection. Catalog numbers of sorted specimens are carried on the 

data bench sheets and in a bound notebook in which entries are logged 

as the samples are sorted. 

B. Regular Testinq Program: 

Procedures for the sorting of live rneroplankton RIS and holding 

them for 96 hours (includes Regular Testing Program, Controls and Air 

Exposure Tests) are as follows: 

1. Live meroplankton sortin5: Samples obtained from the screen 

or other control methods (net, light trap, etc.)ar@subsampled by the 

section supervisor and sorting by technicians commenced. Live or stunned 

organisms for holding are pulled out in lots of five or less (fish eggs 

and larvae) and single individuals (zoea) in an attempt to total 30 

organisms of each species/life stage. Once the organisms �or holding 

are drawn off the first subsample, the rest of the RIS is sorted as 

live, deed or stunned (only for screen samples) and preserved in three 

seperate containers (no counts or final identification is made). If a 

total of 30'organisms of each species/life stage.for holding is not 

available from the first subsample a second subsample is drawn and sorted 

only for the Jive/stunned organisms necessary. The procedure is repeated 

once more if necessary. A maximum of only 3 subsamples per sample are 

processed. For controls, two lots of 30 organisms per available ?.IS species/ 

life stage is sorted per week for holding. Once the organisms for holdlzg 

and the initial mortality estimation are withdrawn from the sample, the 

remains are preserved. Organisms for Air Exposure Testinq zre also prox:ided 

from the sorting of control sanples. Stringent QA procedure is enforced 

during the five sorting process. The section supervisor (Duane Phillips) 

or alternate (Donna Famislietti) draws the subsamples and supervises the 

sorting and data recording (Data Sheet No. 1 - Appendix). He/She then transfers the position-marked containers (500 rril glass jars for fish eggs .and 

. larvae: 2" cube tackle box trays for zoea) to the holding facility supervisor (Gary Comp) or desionated alternate shift supervisor/technician 

(K. McCarthy or E. Myers or R. Dennis or E;. Caraccia). Data Sheet No. 1 

is copied (4 coi)iesl: one cop): is provided to the holding facility supervisor (Corn?); one cop:~ is retained in the section supervisor's (Phillips) 

files: one copy is trznsmitted to Stone and webster's field representati-Je; 

one copy is filed in the project coordinator's files and the oriqinal is 
transmitted to the 'preserved material' section rupervisor (Blanchet). 

2. Holding: On receiving the position marked-containers, the holding 

facility supervisor or alternate records the sorting data (Data Sheet 

No. 2 - Appendix) and places the container in the appropriate water 

table and position (Tables are marked alaphabetically and positions 

within a table sequentially marked. Charts over each table identify 

the exact position sf each container). Checks (observation of dead/ 

live organisms) are thenceforth made on a regular schedule (3,6,12,18, 

24,36,48,60,72,84, an6 96 hours) and appropriate information recorded 

on data sheets (Data Sheet No.2 - Appendix). Dead organisms during each 

check are pulled out, preserved in a labeled vial and placed on the 

transport rack with appropriate entry made on to the transport control 

sheet (Appendix). The labels (external stick-on) contain sample number 

(two digits e.g. lA), subsample number (1 digit e.g. l), table identification (1digit e.g. K), position within the table (1-2 digits e.5. 29) 

and check hour (1-2 digits e.g. 18). An example label is: 1AlK29-18. 

At the end of the 96 hour period all animals are preserved with live and 

dead seperated and identified with h 'D' or 100 (live) respectively in the 

labels. e.g. l.UK29-100. Transport racks are individually labeled 

before use and one rack is used to transport all vials within one sample 

only (e.g. a transport rack specifically marked for sample 1A). When a 

complete day's semple vials are accumulated (e.g. lA through IF-6 samples 

in that day), samples are transported to MML-Sarasota. Samples preserved 

from the initial mortality sorting are labeled with sample No. (e.g. 1A), 

subsample No. (e.g. 1) and condition of organism (e.g., L=live, D=dead, 

S-stunned). An example label would contain: 1A1-L. These samples are 

transported the same day with accompanying transport control sheets. 

Control samples and air exposure test samples are treated similarly. 

Completed Data Sheets No. 2 are copied (5 copies); one copy is retained 

in the holding facility sup'ervisor 's files; two copies are transxitted 

to Stone and Webster; one copy is filed in the YLYL archives; one copy 

is filed in Preserved Material section supervisor's (Blanchet) files 

and the original is filed in the project coordinator's file. 

3. Preserved Material Handlin?: All samples transported from 

the holding facility are received at MML-Sarasota by the section supervisor (Harry Blanchet) or alternate (Tom tong) and checked to ensure 

accuracy of vials transported. The samples are then processed 

7 
(identification, enumeration, length measurement) and data entered on 

Data Sheet No. 3 (Appendix). Four copies of this data sheet are made 

after all quality control checks are made. One copy is retained by 

the section supervisor, one copy is transmitted to Stone and Webster 

field representative, one copy is filed in the MML archives, one copy 

is placed in the holding facility section supervisor's (Comp) files and 

the original is placed in the project coordinator's files. Samples from 

initial mortality are processed similarly and data entered on to the 

appropriate Data Sheet No. 1 (that is, the original that was transmitted 

by D. Phillips to H. Blanchet, see (a) above). Four copies of this 

data sheet are made. One copy is transmitted to Stone and Webster field 

representative, one copy is filed in the holding facility supervisor's 

(Comp) files, one copy is placed in the MML archives, one copy is retained in the section supervisor's (Blanchet) files, and the original 

filed in the project coordinator's files. A11 preserved material from 

the holding facility (after processing and quality control checks) are 

lumped into primary sam?les (e.9- 1A-one Screen Test sample; AEl-one 

Air Exposuze Test; CT1-one Control Group: etc.) and stored until completion of project. 

C. Computer Dzta Entrv: Utilizing Data Sheets 1,2,3 and 4, the 

section supervisor (Blanchet) or a technician transfers data to 

appropriate computer data sheets (examples in Appendix). Checks are 

made to ensure accuracy of data transfer. Two copies of the computer 

data sheets tre made. The original is transmitted to the Stone 

and Kebster (Eoston office) , one copy is placed in the holding facility 

supervisor's (Comp) files, one co9y is placed in the project cocrdinator's 

files an2 one copy is filed in IXYL archives. 

8 
IV. RECOMMENDATIONS 

Based on our preliminary studies' findings and the suggestions of 

our expert consultants, we recommend: 

1. Feeding the organisms (with a mixture of algae and rotifer 

culture) that are held for latent mortality. 

2. Holding the organisms for 96 hours as planned in the ESSOW. 

3. Holding the fish eggs and larvae in 500 ml glass jars (5 

individuals to a container) and zoea in 2" cube tackle box 

trays (single organism to a container). 3" PVC pipes with 

screen bottom should be kept as back-up in the event of 

excessive mortality in closed system. 

4. Collecting control organisms with a plankton net (with backup of a light trap, if necessary). 

5. Eggs that hatch during holding be kept until.the normal duration of the experiment (96 hours) but record kept of thc hatch 

time . 6. Partially changing water in the container (during 48 hour check) 

7. Holding 48 zoea instead of 30 zoea per sample 2s specified in 

the ZSSOW (tackle box trays are in conparment units of 24). 

9 
v. REQUEST FOR AP~ROVALS 

We request that the following items be approved by the Engineers: 

1. Collection of control organisms by primarily plankton nets 

with the use of a light trap, if necessary. 

2, Holding of all organisms in closed systems, (with a back-up of 

open-system containers if a need arose to change). 

3. Feeding the organisms (post-larvae only) with a mixture of 

algae and rotifer at the 24 hr, 48 hr and 72 hr checks. 

4. Changing water partially (larvae only) at the 48 hour check. 

5. Holding 48 zoea instead of 30 zoea per screen or control sample. 

10 
. 

APPEND1X 

EXAMPLES OF PROJECT 

DOCUMENTATION 

AND 

RECORDS 
.. 

Data-Flow for ?lankton net Samples, Spray Wash and Screen 

Efficiency Samples. 

'' --. 

(

"-Field Check List' '63 Calibration Loa ) 

I 

t 

Field 

9 

w 

AI 

;Sample Analysis 7 

(Custody Log 

(Daily Log) 'A Resort 

Bench Sheet %>) 

$

1 Data Transfer 

i Entry 

. 0 

! 

Checks by supervisor 

Task 

--7 Documentation '-

Project Coordinator is custodian 

of these logs 

Secticn Supervisor is custodian 

of these 105s cr data sheets 

P f'ersor.al log 

Copies to 

Or i g irzl to 

m 

Log Records 

PL!lL Coordinator ! 

I 

Archives I 
'<<..< 

.. 

The Mettler balances listed below have been serviced 

by our representative on / 

,,'I/4 -

I

,. ,-c /??.? __ - __ 

This is to certify that the test weights used are tracezble 

to the National Bureau of Standards. 

* ­ .& 

3?: 

'4T 

$A Mettler identification number of test weights used: 

+& yI-. r -1c C.

// ..,- .. Mettler calibration date of test weights used: /G. 4 ,I o*:-n - '1-­

L

National Bureau cf Standards tes: date: .L;L;:?.L ,J .. .: .;' r' 

.& - -. -

Type and serizl number of bzimces service<: 

__ .___ _.. . .. ._. - . 

4-7-
-- 

Data-Flow for regular testing program, Controls and air- exposure tests. 

Control/ A 

screen . Air Exposure 1 Sampling Sampling 1 

1

' Initial 

Mortality 

Estimation 

4 

Log Records 

49 A 

I 

4 k' / 

/ 

/ A \ 

Y 

ProjectY' 

/ I1 

MYL Coordinator 1 

I

Archives -+-----­

ata S eet 

Cj). 

1 

Seawater 

at 

I 

Water-exchange 

V 

Preserved 

Material fiortinq LO~S) 

Sorting c------? 

Bench Sheet Records 

Project /,TT 1 +-

Coordinatoc '1 \ si 

g - v 

PlML Solding 

Archives Facility

Supervisor 

(Comp) or 

Appropriate 

Section Supervisor 

(See QA Manual) 

-J 

S&W 

Final Analysis 

a Checks by supervisor 

Section Supervisor 0Task 

(Blanchet) 0Documentation 

@ 

s 

A 

--+ 

-5 

Project Coordinator is custodian 

of these logs 

Section ~upervisoiis custodian 

of these loss or data sheets 

Personel loa 

Copies to 

Original to 

1 
5. >iODEL ASTM 36C 1 

1. CALIBXATIOK TECHSICLAK [A. J .mWTON 1 

7. TEST DATE L 4-2-80 1 

3. CONDITION RECEIVED 

WITHIN TOLEWCE 

OUTSIDE TOLEWCE 

L. COh'DITIOI\! RETULYED 

WIXIX TOTLi&NCE 

OUTSIDE TOIElWYCE 

5. CERTIFICATED OR EPORTEQ ~ 

l'.CiE ST.L\DARD

METROLOGICAL 

IF FIXED 

CONDITIONS 

u 

REV ._. 

TE?l?ERATURE 72 *OF 

RELATIVE HLTMIDITY 33 X 

3. SEii'L'ICIN(; C'<CLE(?iOi.;THS) 

CEIITIF ICATIOX m 

CALI BRAT ION U 

LO. CALIBPdITION PROCEDURE 1 w3. 1 % 

6. PMX-HOURS TO CALIaRATE [ 2.0 1 

7. $(&-HOURS TO REPAIR I N /A I 

8. SERVICING WEL AFFIXED . 

CERTIFICATION 

CAL IB RATIOK 

LINITED USE WEL 

LIMITED USE TAG ... 

9. 3TXT SERVICIKG DATE 

CE RT IC I CAT IOK 

CfiLIBRATIO?! 

XS 

READING OF STD. READING OF EADl 11I 

O0 +. 2 

12.0 12.0 

2s.o 28.1 

30.0 30.1 

50.0 50.L 

52.0 52 .h 
SAMPLE LABEL 

MOTE MARINE LABORATORY SARASOTA, FL 

Pmj. +: Samp. gear: 

Stat +: 

Repl. *: Samp. day/hr: 

samp. time: 

1 

Tide Ph: sarilp. vol/area: 

CoL by: Anal- by: 

Comment: ChE& by: 
1 2 3 

L 

SUBSAMPLE ID NUMBER: 

A. INITIAL MORTALITY ESTIMATION a. Rough Sorting by: 

b. Final ID by Date -

.DA - Checks:

Rough Sorting : 

Ini tisls/Date 

Final ID: 

Ini tisls/Datc 

NOTE: Lengths are 

in millimetei 

Comments: Preliminary sorting for Initial Mortality Estimation done: YES NO Ey: 

3. HOLDING SAMPLES/SEPARATION 
L 

.. 
. MOTE MARINE LABORATORY Page -of ­ 1600 CITY ISLAND PARK 

SARASOTA, FLORIDA 33577 

Project Z310.85 FMS BIOLOGICAL EVALUATICN 

LATENT SURVIVAL MONITORING ID DATA SHEET 

Sample Subsample C 

Quality Concrol Checks (ID) 

1. Vial Numbers: 

2. Vial NmSers: 

Comments : 

Date Collected : 

-

bv Date: 

by Date: 
MOTE MARINE LABORATORY 

Sarasota, Florida 33577 

Stat ion : Collection Date: day/ni te PROJECT No. 310.85 

FMS Eioloqical Evaluation 

Replicate =: Sample vol . : 

Meroplankton Data Sheet \ 

L A1 iquot 

Vo 1ume I 

Crassos trea ! I 1 I ! 1 . I I ! 

Penaeus P.L. I I 1 

i 

Ca'ilinectes Zoea I

' I 

I ! Menippe Zoea I l l / I 

I

I 

1 

I i 

i ! 

j 

[ 

1 

/ 

j 

l 

f.. 

Anc hoa 1 a rva e ! I ; 

Harengula larvse ' I 1 1 ;i 

'! i 

Men iai a 1a rvae /

I 'l Ii l I ! ; i

I i/ 

Bairdiel la larvae I ! I I I i i i I i

Cynoscion larvae I

I t i I l l -. 

Pogonizs larvae 1 ! I ' ! I j 

anchoa prolarvae i 1 i I 1 ! I ! 

! I I I l l l l I ! i / I

I 

! ! ! I I i I ! I ! 1 I 

Anchoa eg~s I

I ! i l l ! I ! I / 

2arengula eciis I f ! l ! ! i 1 Nenidia "9s i I 

I i 

I i 

I 

I 

Saircie'iz egGs ~ l / l i I i l

Cynoscion escs I [

! 

I t l

i

l

j

i 

j

! 

i l . ;l i , 

I 

Pcconizs ecjss ! 1 

3a:e : Cmme n: t T ' Iltle: 2. :. Date : 

Sate: 
1600 C I T Y 

SARASOTA, 

PHONE: 

WILLIAM R. MOTE 

CHAIRMAN OF THE BOARD 

Revised 3/19/80 

ISLAND P A R K 

FLORIDA 3 3 5 7 7 

(813) 388.4441 

WILLIAM H. TAFT, Ph.0. 

PRESIOENT 

Project: 310.85 

Reference: FMS Eiological 

Evaluations 

INSTRUCTIONS FOR SAMPLE TRANSPORT CONTROL SSEET 

This form is designed to assure accurate traceability of 

samples from the field laboratory to the base lab in Sarasota. 

A separate sheet must be completed for each tray of vials sent to 

Sarasota. It is strongly urged that different types of samples 

(vials) be separated by empty taped rows. 

PACKER : 

1. Complete ths top half of the form. 

2. Either at the time of packing or (better) inmediately before 

loading �or transport, check the total nLT5er of vials listed 

on the sheet. 

3. Count the number of vials in the tray. 

4. Spot-check at least three vial numbers on the sheet to make 

sure those vials are in the tray. Circlemmbers on sheet. 

5. ComFlete the Packer Check co1urr.n. 

6. Sign and date the Packer Check column. 

7. Lock the container with 'he transpor: control sheet. 

TRilh'STOEITER (Driver) : 

Open the container 

1. Verify %he nunber of vials listed on the control sheet. 

2. Verify (count)' the number of vials in rhe tray. 

3. Locate, in the tray, the three vials doujle-checked by the pacKer, 

4. spot-check three additional vial nninbers on rhe sheet to nake 

sure those vials are in -;ne tray. 

5. Complete the Transporter Check column. 

6. Sign and date the Transporter Check col~mn. 

7. Make sure there is a sheet for each tray. 

8. Lock the container with the transport control sheet. 

XECEICTR (Harry or his desiqnee): 

Open the container . ­ 1. Veriry that :he Control Sneet vial nunhers and the vials 

received match one-to-one. 

2. Complete the Receiver Check colamn. 

3. Sign and date the Receiver Check colur;,~. 

3. Give the Control Sheet to Jeff for filin5. 

5. Remove the vials and storeit iz the lab sample container. Lock it 

TFSJSTORTER Xi3 ECZiVER : 

If you find. any discrepancies, whatsoever, refuse to accept the 

delivery. As soon as practical, notify jeff ?atton and the shift 

supervisor on duty to have the shiFment returned to the field 

laboratory for corrective acticn. The socner ihe problem can be 

traced, the easier it will be to correcz. Delay will only compouzc 

the problen. 
m 

0 

w 

\ 

/,r

u 

! G

? OI r-3 

\ 

m 

rk r . 

H .x 

.. 
MOTE NARIb!:'E LLBOlbYl'ORY 

EQUIPMENT CALIBWtTION LOG FOK.AT 

EQUIPP'ENT: 'IODEL NUIYBER : 

PANUFACTURER : SERIAL NUMBE'S : 

STANDAiiD USED: 

PX-CALIBRATION POST-CALIBRATION - .WADING OF STANDARD READING OF TEST INST. READING OF STANDARD READING OF TEST INST. 

-.-

BY: DATE : TIFl :

-

A PPROvE D 

( SUPEXVI SOX) 
-- 

. 

. 

1 

2 

3 

n 

5 

G 

7 

3 

9 

1(I 

11 

72 

13 

14 

15 

1(i 

17 

;8 

19 

20 

71 

22 

23 

7.7 

25 

2; 

?7 

?!i 

-?a... 1 

.XI 

31 

-., -%. 

.).I 

3 I 

..­

.lZ' 

.?I 

... 

.>I 

....,'* 

+I 

I 

.](I j 

J.G. No. Presented by: Date: 

Checked by: Date : 

C 

w

z

z 

3 

E. 

tn 

Pageof ­

-i 

I I ._.-. . _: 

........... 

- . . -_.._._.___ 

.... 

.., 

.. 

. . . 

CONCEPTUAL ENGINEERING DESIGN OF THE UNIT 3 AND 4 

FINE MESH SCREEN INSTALLATION 

BIG BEND STATION 

TAMPA ELECTRIC COMPANY 

Studies are presently ongoing at Big Bend Station to determine how the 

concept of fine-mesh screening can be employed to .reduce entrainment. In 

light of the positive results obtained to date, a pre1i.minax-y conceptual 

design has been developed for applying fine-mesh screens to existing 

Llnit 3 and proposed Unit 4. The intent of finc screening two units to 

minimize entrainment is supported by prcliminary results ns sufficient 

to maintain entrainment levels when Unit 4 is added, st or below those 

which presently exist with three-unit operation without thermal dilution 

pumping . 

Sheet pj.ling would be utilized to enclosc the pump scrccnwell area and 

create a forebay between the fine-mesh screens and thc p”ips. A layout 

of the new screening structure is shown on drawing 12408.04 IiSK-62. 

Each of the six (3 for each unit) dual-flow, fine-mesh screens would be 

fitted in this wall and would discharge into the forebay. The discharge 

opening would be sized to achieve a uniform flow distribution through the 

two parallel screen faces. To ensure proper hydraulic conditions at the 

four circulating water pumps and a relatively uniform flow through each 

of the six screens, the forebay would be extended out from the seawall 

to a distance of about 60 ft into the intake channel. The pumps would 

also be positioned to aid in proper flow distribution such that each set 

of two pumps draws from three screens. 

Stop gates would be provided for use in closing the discharge opening 

in the event that a screen must be stopped or removed for maintenance. 

In case of emergency conditions roller gates would be installed in the 

sheetpile wall between screens and would be opened to stipply water to the 

pumps. To screen the flow and protect the pumps and condenser under this 

emergency operating mode, the existing coarse-mesh (3/8 in.) screens would 

be maintained on Unit 3 and new, sj.milar coarse-mesh screens would be 

installed on Unit 4. 

The dual-flow screen design has been used successfully at Big Bend Units 

1 through 3 with 3/8 in. mesh screens for a number of years and, based 

on fine-screen testing to date, has the necessary features for minimizing 

entrainment and protecting small organisms when using fine-mesh. Pending 

final results of ongoing studies, the number and size of the screens have 

been preliminarily determined on the basis of achieving a screen face flow 

velocity of 0.5 fps at a water level el. of 0.0 NLW. Thus, six, .lo-ft 

wide screens would be required. Each screen would be submerged to el. ­ 21.5 ft. Each of the 63 screen baskets would be equipped with easily 

replaceable 0.5 mm mesh panels and fish collection buckets. The fine mesh 

requires continuous screen operation to prevent clogging, as well as to 

limit the time that organisms are impinged. Since continuous operation 

results in greater wear of the mechanical components than with intermittent 

operation as on the existing screens, more reliability would be achieved 

through the use of heavy duty rollers, bushings, bearings, sleeves, chains, 
and motors. To further reduce maintenance requirements, 10 mm mesh screen 

panels would be provided for use in periods of the year when entrainment 

of meroplankton is not of concern. 

Each fine-mesh screen would be capable of operating continuously at speeds 

of up to 28 ft/min. On automatic control, the screen would run continuously 

at 7 ft/min., assuming that ongoing studies indicate that this speed 

would be adequate to protect impinged organisms. As the head differential 

across the screen reaches 4 in., and then 6 in., the speed would automatically increase to 14 and 28 ft/min, respectively. Should studies 

indicate the need for different speeds than these, the controls could be 

modified to achieve any required speed between 0 and 28 ft/min. 

Each screen would be equipped with a low pressure (approximately 10 psi) 

organism spray wash header on the ascending side and high pressure (40 

to 60 psi) spray wash header for debris removal on the descending side 

of the screen. Separate pumps would supply water to each header and would 

take suction from the fine-screened water downstream of the circulating 

water pumps. These nozzles would have 1/2 in. diameter orifices and woraLd 

be evenly spaced at 1 ft intervals over the 10 ft header length to ensure 

a uniform spray pattern across the screen baskets. 

Although the low and high pressure sprays would wash organisms and debris 

into separate troughs, all troughs would manifold in a common sluiceway 

which would carry collected organisms and debris to a release point north 

of the intake channel (HSK-62). This design will maximize the opportunity 

for survival of any organisms not removed by the low pressure spray, 

but subsequently removed by the debris spray. 

The organism return trough would be sized to achieve a transport velocity 

in the range of 2 to 3 fps at a water depth of from 6 to 12 in. The trough 

would run west along the south side of the intake channel to a footbridge 

from which it would be supported as it transverses the channel. The trough 

would then travel north and east to the channel where it would discharge. 

Total length of the return flume will range from 3,500 ft to 4,700 ft 

depending on the exact location of discharge in the channel. 

To alleviate fouling problems in the trough, it will be divided with each 

half being 18 in. wide by 18 in. deep. With this arrangement, the flow 

would be frequently diverted from one side to the other and the unused 

side would be drained and dried. The trough would be covered with solid 

removable plates to eliminate sunlight, and it could be insulated if 

nccessary to minimize temperature ri.ses as the water travels from the 

screcri to the d i schnrge point. 

The proposed design involves expanding the existing Unit 3 operating deck 

from which the dual-flow fine-mesh screens would hang. The design would 

be similar to the existing screen structure designs at Big Bend with the 

exception of the overall dimensions and number of screens. 

The expanded deck would be supported on piles si.milar to the existing 

units. Also, similar to the existing structure, the operating deck would 

be at el. + 9 ft. The canal would be maintained in the screen structure 

area at a depth of el. - 24 ft. 
Initially, a chain link fence, similar to that presently used at Units 1 

to 3 to exclude large floating debris, would be incorporated into the new 

screen structure and would extend to el - 5 ft. If, in the future, the 

fence is found to be inadequate to protect the fine-mesh screening medium, 

provisions would be incorporated to allow for possible installation of 

stationary bar racks to replace the fence. Such racks would be located 

approximately 14 ft upstream of the fine mesh screens. The rack structure 

would be inclined at a 5-on-1 slope and would have bar spacings of 1.5 in. 

A common, moveable rake would be provided for the removal of debris; the 

rake would raise all debris collected on the bar racks to the operating 

deck and into a rail-mounted hopper. The hopper would traverse the screen 

deck and would be emptied at the end of the rail line for ultimate disposal 

In the event trash racks are added, provisions will be made �or lateral 

fish passageways at the end of the structure. 

Construction would be performed in the wet and would consist of excavation, 

driving necessary piles and sheeting and fabricating the operating deck. 

The traveling screen assembly troughs and pumps would then be installed. 

It may be necessary to shut down Unit 3 during pile driving or installation 

of equipment. 
i 

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COST COMPARISON OF FINE-MESH SCREENS 

VERSUS CLOSED-CYCLE COOLING 

Estimated costs are provided here for a fine-mesh screen system to serve 

Big Bend Units 3 and 4. This system would enclose the conventional intake 

structures of Units 3 and 4 as discussed in Part 11. A duplicate system 

could be installed on Units 1 and 2 if further reduction in entrainment 

is required. These costs are compared to the differential cost (above 

the costs of a conventional once-through system) for a closed-cycle cooling 

system. Table 1 provides a summary of this cost analysis. 

The closed-cycle cooling system which will be used for comparison is a 

mechanical draft cooling tower. An engineering study on closed-cycle 

heat rejection systems for Big Bend Unit 4 was performed. The study results 

indicate that a mechanical draft tower would be the preferred closed-cycle 

system. This tower would be of concrete construction and would utilize 

saltwater as the cooling medium. Tower costs are based upon a design 

which will achieve a maximum drift rate of 0.002 percent of the circulating 

water flow. Site and foundation preparations costs are included as separate 

items. Energy requirements and derating penalties were calculated and are 

included in the estimated costs. The tower requires 4.5 MW of auxiliary

power year round and creates a generation loss due to increased turbine back 

pressure of 2.2 MW on both a summer peak and annual average basis. 

The table presents cost differentials above the cost of a conventional 

once-through cooling system. The additional cost required to add a finemesh screen system to Units 3 and 4 is $10,215,000. The costs to retrofit 

a fine-mesh screen system to Units 1 and 2 would be approximately $7,985,000. 

The cost of the two systems is approximately the same; however, the cost 

of the shared return system is included in the Units 3 and 4 estimate. The 

additional cost of providing a mechanical draft tower is $51,802,000. 
TABLE 1 

COST COMPARISON FOR FINE-MESH SCREENS 

VERSUS CLOSED-CYCLE COOLING SYSTEM 

(MECHANICAL DRAFT TOWER) 

Figures - are in (Thousand $)

Des cri ption 

Structural 

Cooling Tower s( Basin 

Other Structural 

Total Structural 

Electrical 

Mechani ca 1 

Instrumentation 

Building Services 

Environmental 

Total Direct Cost 

Dis tributables 

Indirects 

AF1 (10%) 

Total Present Day 

Escalation 

TECO Local Charges 

Units 3 Sr 4 

-

- 2,080 

100 

2,550 

Incl in Mech 

Incl in Mech 

Incl in Mech 

4,730 

420 

410 

560 

6,120 

1,263 

333 

Units 1 SI 2 Cooling Tower 

-

-

1,670 

100 

1,760 

Incl in Mech 

Incl in Mech 

Incl in Mech 

3,530 

300 

310 

410 

4,550 

939 

247 

52 

672 

6 ,460 

6,042 

6,481 

12,523 

1,150 

753. 

208 

14 

32 

14,680 

2,165 

600 

1,755 

19,200 

8,000 

1,224 

25 7 

A 2 692

31,373 

Administrative and General Expense 70 

IDC 904 

Total Capital Cost 8,690 
TABLE 1 (cont) 

OPERATING COST PENALTIES 

Figures are in (Thousand $) 

Description Units 3 & 4 Units 1 & 2 Cooling Tower 

Circulating Water Pump - 106 106 - Additional Head Required 

Auxiliary Power for System 414 414 12,932 

Generating Loss Due to Turbine 

Back Pressure Annual Average - 6.324 -

Totals 520 520 19,256 

OPERATION AND MAINTENANCE COSTS 

Description 

Screens 

Screenwash Pumps 

Organism Return 

Total 

Escalation 

Total Cost 

Total Evaluated Cost 

(Total Cost ) 

(Fixed Chg Rate) 

TOTAL COSTS 

Des cr i ption 

Capita 1 

Revenue Requirements 

Ooerating Cost Penalties 

Operation and Maintenance 

Total Evaluated Cost 

Figures are in (Thousand $) 

Units 3 & 4 Units 1 & 2 Cooling Tower 

- 30 30 

7.5 7.5 ­

24 24 -

- 61.5 61.5 

- 105.5 105.5 

167 167 195 

1,005 1,005 1,173 

Figures are in (Thousand $) 

Units 3 & 4 Units 1 & 2 Cooling Tower 

8,690 6,460 31,373 

520 

-

520 19,256 

1,005 1.005 A 1 173

10,215 7,985 51,802