ML18283B708

an Environmental Assessment of Operation Oo Browns Perry Nuclear Plant with a Thermal Limit of 90oF Maximum Temperature in Wheeler Reservoir

ML18283B708
Person / Time
Site:	Browns Ferry
Issue date:	07/31/1977
From:	Tennessee Valley Authority
To:	Office of Nuclear Reactor Regulation
References
Download: ML18283B708 (147)

Text

TENNESSEE VALLEY AUTHORITY An Environmental Assessment, of Operation of Browns Perry Nuclear Plant With A Thermal Limit of 90 P Maximum Temperature in Wheeler Reservoir.

JULY 1977

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Table of Contents

~Pa e Abstract 1.0 Introduction 2.0 Thermal Standards 3.0 Condenser Cooling Water Systems 3.1 Diffuser System 3.2 Cooling Towers 4.0 Thermal Regime of Wheeler Reservoir 4.1 General 14

4. 2 Stratif ication 14 4.3 Natural Water Temperatures 14 4.4 Streamflow 16 5.0 Equatic Ecology of Wheeler Reservoir 24 5.1 Fishery Resources 24 5.2 Plankton and Benthos 6.0 Effects of Operation at 90oF Maximum 75 6.1 Fishery Resources 75 6.2 Plankton and Bethos 80 7.0 Hydrothermal Analysis of Helper and Open Mode 91 Condenser Cooling Cooling System Operational Modes 91 7.1 Condenser 4

Mixed River Temperature Probabilities 92 7.2 7.3 Simulation of Extreme Condition 93 7.4 Far Field Analysis of Diffuser Discharge 95 8.0 Power Supply Situation 105

ABSTRACT A combination of extreme meteorological conditions and inadequate cooling tower performance has resulted in a severe reduction in generation from TVA's three unit Browns Ferry Nuclear Plant during periods of peak system demands. These reductions were necessary to meet the current State of Alabama water. temperature standards for the Wheeler Reservoir.

r The current Alabama standards were adopted because it was felt at that time the standards were necessary to ensure the maintenance of the fishery habitat of the reservoir. Subsequent studies performed by TVA (summarized in Section

6) have indicated that the current standards are unnecessarily restrictive for the protection of the fishery of this reservoir. Consequently, TVA requested from the Environmental Protection Agency a temporary modification of the thermal standards specified in the NPDES permit issued for Browns Ferry.

TVA is currently exploring methods of correcting the heat dispersal problems existing at Browns Ferry. Completion of necessary modifications is anticipated about mid-1980.

This environmental assessment describes the current thermal standards, condenser cooling water system, thermal regime of Wheeler Reservoir, kffects of operation on the aquatic biota of the reservoir, and the power supply situation. Based on the thermal regime resulting from the plant and the t hydrothermal analysis provided herein, the assessment concludes that. long-f term operation of the plant at less restrictive thermal standard (maximum temperature of 90 0 F.) will not result in adverse environmental impacts to the biota of Wheeler Reservoir.

1.0 Introduction The Browne Ferry Nuclear Plant was initiated in 1966 as part. of TVA's program designed to meet pro5ected load requirements. Construction of the plant began in May 1967 after the Atomic Energy Commission (AEC) issued provisional construction permits for units 1 and 2. Unit 3 was given a construction permit in July 1968. Commercial operation was achieved on units 1, 2, and 3 on August 1, 1974; March 1, 1975; and March 1, 1977, respectively.

-The operation of the three units at Browns Ferry Nuclear Plant has been intermittent since the fall of 1973. Unit 1 was initially placed on line in October 1973 and operated continuously at near full load until March 1975, when it was shutdown because of the cable fire. Unit 2 was placed on line in August 1974 and operated at near full load until March 1975 when it was also shutdown because of the cable fire. Following the fire outage, all three units were placed in service in September 1976, and have operated at or near full power since that time, except for periods when load reductions were required to meet river temperature limits.

The history of the consideration of auxiliary cooling facilities and the evolving thermal criteria as these criteria were finally adopted by the Environmental Protection Agency (EPA) is described in considerable detail in the final environmental statement (issued on September 1, 1972).

Aspects that pertain to the present situation at Browns Ferry Nuclear Plant are repeated herein.

The Tennessee Valley Authority has taken action to comply with applicable thermal water quality standards of the State of Alabama in the operation of the 3-unit Browns Ferry facility by installing mechanical drait

cooling towers. However, inctdequate cooling tower performance has resulted in drastic curtailment of power generation during peak summer periods when peak load demands are critical on the TVA system to meet thermal standards.

Thermal discharges resulting from power operation are being controlled in order to meet the applicable thermal standards. This document describes (1) the need to operate Browns Ferry in a manner which will not result in water temperature in excess of 90 F after reasonhhle mixing for an

~deHnite.'eriod, and (2) the need to be able to discharge cooling tower blowdown when natural occurring water temperature is near or exceeds 86 F, and (3) the effects of operating the plant within these limits. A summary description of the design, and operation of the Browns Ferry heat removal system, along with a discussion of thermal standards, and reservoir characteristics are also included. This information provides the basis for discussions regarding the ways in which such operation can be accomplished consistent with the Federal Water Pollution Control Act Amendments of 1972.

On the basis of TVA's environmental evaluation that facility operation limiting the maximum stream temperature to 90 F. would not detrimentally affect the aquatic environment of Wheeler Reservoir, TVA sought relief from the 86 F. limitation to allow utilization of the plant's generating t

capacity. On July 1, 1977, TVA staff met.'ith personnel from EPA, Region IV, to explain the power systems situation, to seek the needed thermal limitation relief, and to discuss the resulting environmental effects. During this meeting is was determined that, with EPA concurrence, the most efficient procedure for obtaining such relief would be a TVA request for adgudicatory hearing.

EPA expressed Support for TVA's environmental evaluation and proposed operation. On July 7, 1977, a meeting was held with James Warr, Chief Administrative Officer, Alabama Water Improvement Commission, to discuss these topics. An AWIC concurrence with TVA's proposed modified operation was obtained. On July 8, 1977, TVA representatives discussed the existing situation and status of other regulatory agency discussions with NRC staff.

On July 13, 1977, TVA.transmitted a petiiton for adjudicatory hearing to EPA and a letter requesting concurrence in the proposed facility operation to James Warr. EPA and NRC concurrence with the proposed interim operation was received on July 15, 1977, by letter and verbal concurrence was received from the staff of the Alabama Water Improvement Commission. A confirming letter was received from the AWIC Staff dated July 18, 1977, on July 20, 1977.

2.0 Thermal Standards The heat dispersal facilities for the Browns Ferry plant were originally I

designed and constructed to meet water temperature standards which were fudged,by TVA,to be adequate to protect aquatic life (Reference Supplements E

and Additions to Browne Ferry Draft Environmental Statement issued November 8, 1971). The State of Alabama subsequently proposed identical standardswhich '

would permit a temperature rise of 0 10 F with a maximum temperature of 93 0 F.

In April 1971, EPA held a Standard-Setting Conference for the interstate waters of the State of Alabama in Montgomery, Alabama. One of the recommend-ations made by EPA at this conference was that the State of Alabama adopt temperature standards that would limit the maximum temperature rise of a 0

stream by the addition of heat to no more than 5 F with a maximum allowable 0 in the River water temperature not to exceed 90 F, except that Tennessee Basin and portions of the Tallapoosa River Basin which have been designated by the Alabama Department of Conservation as supporting smallmouth bass, 0

sauger, and walleye, the temperature shall not exceed 86 F. Wheeler Reservoir

'as been officially designated as this type fishery. The State of Alabama I

did not immediately adopt these recommended temperature standards. Meanwhile, EPA had approved temperature standards for Costal and Piedmont zone streams in both Virginia and North Carolina that would allow a 5oF rise and a maximum temperature of 90 F. While changes to more restrictive standards were often mentioned, it was not until December 1971 that EPA informed TVA that it would not accept any maximums for the waters of the Tennessee River Basin in Alabama other than the following:

0 "Temperature shall not be increased more than 5 F above the natural prevailing background temperatures, nor exceed a maximum of 86 F."

These temper'ature standards proposed by EPA for the State of Alabama were published by EPA in the March ll, 1972, Federal Re ister. Alabama adopted these standards and EPA approved them on September 19, 1972.

Based on the studies described in Section 6 of this assessment, TVA 0

believes the thermal standard of 86 F maximum temperature is unnecessarily restrictive for the protection of the aquatic biota in the Wheeler reservoir.

3.0 Condenser Coolin Water S stems 3.1 Diffuser S stem The original condenser cooling water system for the Browns Perry Nuclear Plant consisted of a once-through system. It was recognized early in the plant design stages that the condenser water should;be di'scharged directly'into"the'urface stratum of 'Wheeler" Reservoir.

Instead, it was decided that by means of a diffuser, the condenser water should be mixed as quickly as possible with as much unheated river water as possible. By this procedure, no excessively warm surface stratum would exist and the mixing zone would be restricted to a relatively small area.

"I Based on TVA studies which were discussed in the draft environmental statement and the experience of others at the time Browns Perry was designed, it was concluded that these heat dispersal facilities would adequately protect the waters of Wheeler Reservoir for the following uses: public water supply, swimming and other whole body water-contact sports, fish and wildlife, and agricultural and industrial water supply.

Each unit has its,own distinct flow system consisting of pumps capable of producing'a flow of 1,450 cfs (total of 4,350 cfs for three units),

conduit leading to a turbine condenser, and a discharge conduit leading to an underwater diffuser in Wheeler Reservoir.

Pigure 3.1-1 shows the;physical..relationship:mf the-caolfug~water conduit and diffuser pipes to the main channel and to the overbank areas of Wheeler Reservoir at the plant site. The diffuser system design is shown in Figure 3.1-2. Thermal diffusion is accomgif;shed by means of three perforated pipes, connected to the discharge conduits os the

three units. These perforated corrugated steel pipes are laid side-by-side across and partially buried in the bottom of the 1,800-foot-wide channel. The channel is approximately 30 feet deep. The pipes are 17'feet, 19 feet, and 20 feet 6 inches in diameter and of differennt lengths. Each has the lest 600 feet perforated on the downstream side with more than 7,000 two-inch diameter holes. Thus, approximately 22,000 holes spaced 6 inches on centers in both horizontal and vertical directions distribute the cooling water into the river for thermal mixing.

As discussed above, the diffuser system was designed to meet a temperature criteria of 10 F thermal rise above ambient water temperature with a maximum temperature not to exceed 93 F after reasonable mixing. In light of EPA's letter of December 17, 1971, which stated that the only acceptable thermal standard for the 0

State of Alabama would provide for a 5 F rise and 86 F maximum temperature, and TVA's policy to take appropriate action on a timely basis to meet any further applicable standards, TVA determined that the diffuser system was not adequate to ensure acceptable conformance with this proposed standard~ The alternatives of mechanical draft cooling towers, natural draft cooling towers, spray canal system, and cooling lake for heat dissipation were reevaluated and it was decided at that time that mechanical draft cooling towers would provide the best long-term solution to meet the more stringent thermal standards. The towers would supplement the diffuser system in order to comply with the new standards.

3.2 Cooling Towers By contract with the Ecodyne Corporation of Santa Rosa, California, TVA purchased and had installed a system of six mechanical draft cooling towers. The towers were completed in May 1976, but were not needed for condenser cooling during the summer of 1976 because It was the'lant was not in operation. not until the spring of 1977 that the towers were actually placed in service.

A flow schematic diagram for the tawed,id +bown M 'P+gre 3 2~3 ..

This modified system is designed to be operated in either open, helper, or closed modes, depending on plant generation, riverflow, and ambiene water temperatures. For a typical year, helper mode operation is expected during the early spring and fall periods, and closed cycle operation M expected during all or most of the summer months to meet the present state thermal standards.

During closed-mode operation of the mechanical draft cooling towers, a certain portion of the condenser circulating water must be removed from the cooling towers as blowdown. This blowdown limits the concentration of dissolved solids in the'ater which would otherwise interfere with operation of the towers and associated equipment. The amount of blowdown has been estimated to be about 110 ft3 /s.

The quantity of makeup required in the closed mode operation is dependent on the following items: (1) amount of blowdown, (2) the amount of evaporation from the towers, and (3) drift losses. With a blowdown dissolved solids concentration factor of 2, the total makeup required has been approximately 6 percent of the circulating waterflow, or 220 ft3 /8.

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Based on tests conducted by TVA and the manufacturer in May 1977, it has been concluded that the'odified cooling system is not adequate to permit normal plant operation while on closed-cycle cooling. Recent L operating experience has demonstrated that the capability of the mechanical draft cooling towers is reduced by 20 percent or more conditions result in a recirculation of the cooling when'eteorological tower vapor plume. This reduction in cooling tower capability results in an increase in the tower, discharge water temperature of around 3".5 F above design conditions. The reduced tower capability coupled with extremely high ambient wet bulb temperature has required reduction in plant generation of 50 percent or more during periods of peak system demands.

In addition to these inherent operating problems, TVA recently experienced the partial collapse of the No. 5 tower at Browns Ferry making it unavail-able for operation for an indefinite period of time. A similar failure of'

(

an Ecodyne tower at another power plant in Texas makes the continued structural integrity of the remaining cooling towers at Browns Ferry questionable without substantial modifications. Structural repair of the type needed cannot be made to a tower without removing it from service.

Thus, we will experience additional constraints on our ability to operate the plant within the present temperature limit of 86 F and at any reaspn-able generation level until these problems are corrected. Thus, a temporary relaxation of the maximum temperature limit of 86 F to the proposed 90 F value is urgently needed.

TVA recognizes that prompt and effective actions must be taken to improve the cooling tower capability, and steps are already underway to do so.

Immediate actions include (1) thoroughly inspecting and assessing the t

structural condition of the towers and initiate needed repairs; (2) increas-,

ing the pitch of the fan blades as much as possible to obtain more airflow,

g 10 and (3) to investigate ways to prevent or significantly reduce the vapor entrainment problem.

TVA is evaluating several long-term modifications to the condenser cooling water system, including adding more heat removal capacity consisting of more cells or additional towers. Depending on the evaluation of reasonable alternatives,

'\

it is not anticipated that a permanent engineering solution to the cooling system problem will be completely implemented until about mid-1980.

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4. 0 Thermal Re ime of Wheeler Reservoir 4.1 General Browns Ferry Nuclear Plant is located on Wheeler Reservoir, which is one of TVA's main stream reservoirs on the Tennesee Mver. The hydraulic regime'n the reservoir is controlled by the operation of i

TVA's Guntersville Dam upstream of the plant and Wheeler Dam down-stream. These prospects are operated primarily for navigation, flood control, and power production.

4.2 Stratification Wheeler Reservoir exhibits weak thermal stratification during the summer months due primarily to the relatively short transit time within the reservoir and the fact that the power intakes on the two dams withdraw water from the entire vertical depth of their respective reservoirs.

4.3 Natural Water Tem eratures It is very significant that natural water temperatures exceeding the current 86 F maximum have been observed in Wheeler Reservoir.

In the operation of the Tennessee River hydroelectric prospects, TVA has for years made weekly observations of the water temperatures in the releases from dams. Table 4.3-1 summarizes these observations for the period 1960 to 1976 . Table 4.3-2 shows for the years

$.966-1975 the month-by-month occurrences of the number of days the natural temperatures of the Wheeler releases equalled or exceeded 86oF

15 In conjunction with the collection of preoperational data for the Browns Ferry site, water temperatures in Wheeler Reservoir have been monitored by permanent recording stations. The recorded temperatures range from about 40 F in the winter to a typical maximum of 85-90 F at the surface in the summer. The maximum top to bottom vertical temperature difference is about 5-8 F. 'Natural water temperatures above the maximum temperature standard of 86 F have been recorded over much of the reservoir ."

depth. These data indicate that there is no significant change in the temperature of the inflow and outflow of Wheeler Reservoir. Thus, with the exception of the surface waters which are subject to diurnal temperature fluctuation resulting from meteorological conditions, the temperatures of the Wheeler Dam releases are almost identical to the average water temper-atures at the Browns Ferry site.

The highest water temperatures, at the plant site since the monitors have been installed were recorded during the summer of 1969 and illustrate the extent to which natural temperatures have exceeded the 86 0 F standard.

Although all data have not been evaluated, the river temperatures recorded during the summer of 1977 are very similar to those recorded in 1969.

The monitor at Tennessee River mile (TRM) 293.6 about 0.4 mile downstream of the plant, has ten thermistors. One of these thermistors is mounted at an elevation of 550 feet (MSL) which, under normal Wheeler Reservoir operation, will vary from about three to six feet below the water surface during the summer months. In the application of temperature criteria adopted for the State of Alabama, the temperature has been measured at a depth of 5 feet in water 10 feet or greater in depth, which is the case for Wheeler Reservoir.

Table 4.3-3 shows the daily maximum and average temperatures recorded for this one thermistor during the summer of 1969.

16 4.4 Streamflow-Since 1937, the U.S. Geological Survey has maintained a streamflow gaging station at Whitesburg, Alabama, about 39 miles above the Browns Ferry site.

t The average daily streamflow at this station for 46 years of record is about 42,500 ft3 /s. At the Browns Ferry site the average annual streamflow is estimated to be about 45,000 ft3 /s. Based on the Whitesburg gage data for the period 1951 to 1970, Table 4.4-1 lists the percentage of days the mean daily flows at the Browns Ferry site could be below the indicated discharge.

The operation of Wheeler and Guntersville Dams results in wide fluctuations within the daily period represented by the mean daily streamflows. The hourly releases, from Guntersville and Wheeler Dams for. 10 years of record (1959-68) are illustrated by the flow duration curves of Figures 4.4-1 and 4.4-2. These hourly records show that the periods.~6f low or no flow are only a matter of" houis in duration;,Therefore,'he'ma5ority of.<the no or low flow occurrences can be eliminated by making adjustments in the daily operation of the Guntersville and Wheeler Dams. TVA has committed to make these operating adjustments as one method of complying with water quality standards.

Table 4.3-1

SUMMARY

OF WEEKLY OBSERVED WATER TEMPERATURES IN THE RELEASES FROM GUNTERSVILLE AND WHEELER DAMS 1960 TO 1976 Maximum Temperature Minimum Temperature Number of Days Natural Temperature OF OF E uailed or exceeded. 86 F Year Guntersville Wheeler Guntersville Wheeler Guntersville Wheeler 1960 82.4 86.0 41. 0 42.8 0 16 1961 82.4 82.4 39.2 41.0 0 0 1962 84.2 86.0 39.2 41.0 0 8 1963 82.4 84.2 39.2 39.2 0 0 1964 84.2 86.0 41.0 41.0 0 1 1965 84.2 86.0 42.8 44.6 0 1 1966 86.0 86.0 37.4 37.4 1 36 1967 80.6 80.6 42.8 44.6 0 0 1968 86.0 87.8 41.0 42.8 1 22 1969 88.7 87.8 41.0 41.0 15 30 1970 84.2 87.8 39.2 37.4 0 17 1971 84.2 86.0 41.0 41.0 0 2 1972 84.2 84.2 44.6 44.6 0 0 1973 84.2 86.0 42.8 41.0 0 7 1974 82.5 86.0 46.5 48.2 0 8 1975 84.2 84.2 44.6 48.2 0 0 1976 84.2 84.2 40.1 39.2 0 0

Table 4. 3-2 NUMBER OF DAYS THE NATURAL TEMPERATURES OF THE WHEELER. RELEASES E UALED OR EXCEEDED 86 F 1966 1967 1968 1969 1970 1971 1972 1973 ~l 74 1975 JuIle 0 1 0 0 0 0 0 0 17 .0 28 0 0 0 August 19 21 0 16 0 0 - 0 0 September 0 0 0 0 0 0 0 0 0 TOTAL 36 21 29 17 2 0 0

J P Table 4.3-3 DAILY RESERVOIR TF2PERATURES WHEELER RESERVOIR TRM-293.6 - Summer 1969 Temperature Readings Fehrenheit Sensor at Elevation 550 Feet Date Maximum for Da Avera e for Da tune 16 77.6 77-2.

17 77-2 76-5 18 78.7 77-4 19 79-7 -

77-8 20 . 79-7 78.8 80.7 78.6 22 82.0 80.2 23 82.4 80.8 24 82.1, SZ,.2 25 83.6 83..9 26 83.8 82.4 27 85.0 82.3 28 85.4 82.9 29 86.2 84.2 t~ 30 1

86.8 85.8 87-9 84.8 84.7 S4.7 3 85.8 84.5 86.2 84.8 5 86.6 85.7 6 By.8 86.1 ""

7 87-5 87.o .

, 8 88.6 86.9 9 87.9" 87.2 10 87.6 86.5

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11 88.7 86.8 12 S7.6 '6.5 13 87.9 86.7 14 88.6 86.8 15 87.4 86.7 16 87,2" 86.8 3.7- 86.6 85-7 18 85.1 19 86.5 85.1 20 85.4 21 22 87.6 86.7 23 86.9 86.4 24 86.6 85.5 86.8 85.6 26 8?.9 86.2 86.7 85.8

20 Table 4.3-3 (continued)

Temperature Readings - Fahrenheit Sensor at Elevation 550 Feet Date Maximum for Da Avera e for Da Ju1y 28 85.9 85.1 29 65.1 84.5 30 85.8 84.4

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84.1 S2.9 3.4 84.3 83.3.

0 15 83.4 82.6

21 Table 4.4.1 Tennessee River Percent of Days Mean Daily Discharge Mean Daily Discharge at Browns Ferr Is Lower 50,000 ft3 /s 76 45,000 67 40,000 56 33,000 35 30,000 27 25,000 17 205000 10 15,000 10,000 5,000 1,000 0.3

22 120 ZOO 90 80 8 Vp

> 60 50 40 20 0

0 10 20 30 40 50 60 70 80 90 100 Percent of Time Figure 4.4-1 Gunt~:".~rille Dam Hourly Flow 10.Years of record 1959 -"1968

220 60 2O 60 50 40 30 20 10 0

,0 10 -20 30 40 50 60 70 80 90 100 Percent of Tire Figure 4.4-2 Wheeler Dam Hour>@ Flow 10 Years of record lo68 '959

5.0 A uatic Ecolo of Wheeler Reservoir 5.1 Fisher 'Resources Wheeler Reservoir supports a warmwatex fish. fauna considered typical of large reservoirs in the southeastern United States. Sible 5.1-1 summarizes the species which were recorded in the four-year preoperational monitoring survey of the area. In addition to the typical waxmwater assemblage, three species thought to be more commonly associated with cool water reservoirs, lakes, and rivers have been recorded:'alleye (Stizostedion v. vitreum),

latter species form the center of concern in terms of the aquatic thermal standards established for the Tennessee River. It is appropriate, therefore, to begin the discussion of the possible effects of plant operation under the proposed thermal criteria with a consideration of these species. In several instances, general reviews of the literature are used in order to reduce the number of specific citations; these reviews axe identified with an asterisk in the Literature Cited Portion of Section 6.

in North America describes a rough, inverted triangle bordered on the north by northern Minnesota and Quebec, by the western Appalachians on the east, and Missouri, Iowa, and the eastern Dakotas on the west. The Tennessee River system in Alabama forms the apex of the triangle (Trautman, 1957; Hubbs and Lagler, 1958). Smith-Vaniz (1968) indicates the Alabama distribution to be limited to the Tennessee River system. Dahlberg and Scott (197la, b) report A

introductions of smallmouth in streams of the Appalachian foothills (Coosa, Savannah, and Chattahoochee river systems) in Georgia, Since the Coosa River contributes to the Mobile Bay drainage system (Smith-Uaniz, 1968), range expansion of the smallmouth in Alabama may occur. Other introductions outside

o 25 of its normal range Xn North. America have occurred; for example, California (Emig, 1966), and are expected to continue because of the sport value of the species.

Smallmouth bass tend to inhabit cool, flowing streams of intermediate gradient (0.75 to 4.7 m/km; 4 to 25 ft./mile) and.large lakes having some current, reefs or bars, and gravel or x'ocky shorelines (Trautman, 1957; Emig, 1966).

Thermal preferences in the field have been reported from 21 to 26.7C; a final thermal preferendum of .28C was determined for young and yearling smallmouth (Ferguson, 1958).

Mean surface temperatures (July through. September) for 18 bodies of water containing smallmouth populations ranged from 17.4 to 27.8C (C:oble, 1967).

More recent work has established that smallmouth bass can have higher thermal preferenda. The results of recent studies (Table 5.1-2)show,that smallmouth acclimated to temperatures between 20 and 33C exhibit mean thermal preferenda

,of from 29 to 31C with ranges of from 25 to 35C.'eynolds and Casterlin's (1976) results also show that the mean day-night preferenda for smallmouth bass were slightly higher than for largemouth bass. Cherry et al. (1977) noted that smallmouth acclimated to 27 and 30C exhibited avoidance to temperatures h

of 33C while those acclimated to 33C avoided temperatures of 35C; they conclude that 35C represents the seven-day upper lethal temperature for the species.

Dickson et'l. (1976) report collecting smallmouth bass in a thermal discharge at 35C and Wrenn (1976) reports that sonic-tagged smallmouth remained up to three days in a heated discharge at temperatures from 31 to 33,4C, Smallmouth bass are omnivorous throughout their life span, changing generally from a zooplankton-insect 'diet when ycung to an insect-macL'vcrustacean-fish

26 diet as adults. Total annual growth has been correlated with mean surface temperatures from July through September (Coble, 1967); the data are sufficiently variable, however, to indicate possible relationships with other factors, i.e., water quality, food, area, parasitism (Emig, 1966; Coble, 1967}.

Spawning activity has been reported to commence at from 10 to 24C for a variety of localities (Emig, 1966; Neves, 1975). Nest. sites are at variable depths up to 3.6m and tend to be in areas, sheltered from direct wind or wave action; gravel or rock substrates are preferred. Developmental periods range from 10 days at 13C to 2.5 days at '25.6C. Newly hatched young remain in or near the nest for several days, Parental care of schools of fry continues until the fish reach approximately 25 mm total length, at which time the young disperse among aquatic plants Qmig, 1966}.

Walleye (Stizostedion v. vitreum) The distribution of walleye in North 'America incorporates an area defined by the Mackenzie River, Great Slave Lake, and Peace River system of British Columbia eastward to Hudson Bay and Labrador, south on the Atlantic slope to central North Carolina, southwest through'orthern Georgia, Alabama, Mississippi and northern Arkansas, and northwest through eastern Kansas, Nebraska and the central and western Dakotas to Canada (Trautman, 1957; Hubbs and Lagler, 1958}, Successful introductions

)

have been made in reservoirs in Oklahoma (Grinstead, 1971), California (Goodson, 1966}, and New Mexico (Jester, 1971) .. Smith-Va'niz (1968) reports the species for the Tennessee River system, Mobile Ray, and Escambia drainages in Alabama. Brown (1962) reports walleye present but not common throughout central and southern Alabama Xn the Alabama and Tombigbee river system.

27 Walleye have been successfully introduced in Lakes Lankier and Hartwell and unsuccessfully in Lake Sinclair in Georgia (Dahlberg and Scott, 1971b).

Cook (1959) reports several collections from counties along the Pearl River and its tributaries in southern Mississippi and in the Mississippi River, but it has never been known to occ'ur in large numbers in the state, Walleye 'tend to inhabit large lakes and streams having relatively clear water.

Sustained popu1ations are=found throughout the oligotrophic-eutrophic spectrum, but walleye never become abundant in heavily vegetated bodies of water (Niemuth't al, 1962; Goodson, 1966}. Ferguson (1958) reports sustained walleye populations occurring at August (presumably maximum) temperatures of 20 to 23C; Dendy (1945} reported a preferred summer maximum temperature of 25C and Goodson Q966) reports a temperature range of 0 to 32C for sustained populations. Regier, et al. (1969) .~rt *that some. resident populations tolerate water temperatures up to 30C for extended periods. Smith and Koenst (1975) report that the optimum temperature range for growth of juvenile walleye extends. from 19 to 25C and estimate that zero net growth occurs'bove 28C.

Koenst and Smith (1976) report that, for juvenile walleye acclimated to 25.8C, 100 percent survived 96-hour exposure to 31C and 10 percent survived exposure to 32C; they estimate the upper lethal temperature (96-hour TL50) to 31.6C.

Xnvestigations presently underway at the TVA-EPA cooperative Browns Ferry Biothermal Research Project have shown continued survival and growth of juvenile walleye for'58 days at temperature.s exceeding. 28C and ranging up to 33C.

Walleye are generally piscivoroua as adults; young walleye utilize plankton and aquatic insects for a short t6ne, but in most cases shift rapidly to fish as a food source. Early growth and survival have been associated with the

28 timing of the supply of forage fish. (Jester, 1971) in New Mexico; however, Priegel (1970) did not find a similar relationship. Growth of walleye appears to be more rapid in the warmer waters of its occurrence (Goodson, 1966), but no specific temperature data axe available, Walleye spawn in a variety of habitats (Priegel; 1970); most spawning occurs in streams or along lake shores over rocks, gravel, and sand, but Priegel (1970) noted spawning in flooded maxsh and bog vegetatio'n, Peak spawning occurs at water temperatures of about 6 to 8C; temperature ranges reported from several studies and reviewed by Priegel (1970) axe 3 to 14C,

)

do walleye. Txautman (1957) and Hubbs and Lagler (1958) describe their distribution as occurring from the Hudson Bay drainage to New Bxunswick, southward west of the Appalachians to Meat Virginia; to the Tennessee River in Alabama, to eastern Oklahoma and the Red River in Texas, to eastern Kansas, Nebraska, Wyoming, and southwestern Iowa and Montana. Smith-Vaniz (1968) reports the Alabama distribution is restricted to the Tennessee River system C

and Cook (1959) reports sauger in the Mississippi, Tennessee, and Pearl River watersheds in Mississippi, There are no Georgia records of native sauger, but it has been introduced in the Savannah and Chattahooche rivers of the 7

Savannah and Apalachicola drainage systems (Dahlberg and Scott, 1971a, b),

The life history of the saugex is not well known, especially in terms of thermal preferences, Sauger Are most commonly found in large lakes, rivers, and reservoirs. Dendy Q945) reported a thermal preference of 19,5C based on field studies in Norris Reservoir, Tennessee; Gammon (1970, 1973) reported" q summer range of preferred temperatures of 22 to 28C in the Wabash. River,

29 Xn the latter studies;, aauger showed a clear avoidance of temperatures present in the mixing zone of a steam plant discharge (30 to 34C).; the maximum, temperature in which sauger were caught was 29C, Koenst and Smith. (1976) report that optimum growth of Juvenile sauger occurred at 22C, For juveniles acclimated at 23.9 and 25.8C, 87.5 percent survived 96-hour .exposure to 30C, but none survived exposure to 31C (although 12.5 percent of those accli~ted to 19.9 and 22C did); the upper lethal temperature (96-hour TL50) was estimated to be 30.4C (Koenst and Smith, 1976). Yoder and Gamon (1976) noted that aauger avoided the heated effluent of a power plant (temperatures of approximately 33 to 37C) but were caught in large numbers in the discharge

't zone during the wi'nter when" effluent temperatures were 8 to 12C (vs 4C ambient).

Teppen and Gamon (1976) noted declines in sauger abundance immediately below three power plants on the wabash River, Sauger are essentially piscivorous after their first year of life. Habitat preferences are poorly known, but sauger are generally regarded to be open-water species. In main stream reservoirs, sauger appear to be most common in the upper reaches including the tailwaters. Spawning occurs over, gravel or rubble substrate in tailwaters, tributaries, and over reefs at water temperatures of 6 to 12C (Priegel, 1969),

30 Fish populations have been sampled quarterly since autumn, 1968, at three locations in the reservoir. Additionally, rotenone samples, <

larval fish samples, and creel censuses have been performed on an annual basis. In terms. of thermal effects, only the area from the plant site (TRM 294) downstream to Wheeler Dam (TRM 275) is of concexn. Table 5,1>>3 summarizes catch I

statistics for the three species in'ill nets fished immediately downstream from the plant diffuser discharge (Station 1, TRM 293). While walleye did not occur in this area, walleye were caught twice in samples taken directly across the reservoir from the plant site (Station 3); in autumn, 1970, one walleye was taken in 39 net'-nights; in summer, 1972,two walleyes were taken in 34 net-nights of effort; in autumn, 1972, one walleye was taken in 40 net nights of effort. During the operational period, one walleye was taken at Station 1 in 1974 and one was taken at Station 3 in 1976 (Table 5.1"4) ~

Smailmouth,occurred only in the autumn and spring quarters during the preoperational period; a similar pattern has been noted since plant startup Table 5.1-4. Sauger occurred more regularly, albeit at low numbers in the preoperational period (Table"5;1-3)'and occurred most frequently'-'in the autumn and spring quarters; their abundance and frequency of occurrence since commencement of plant operation has increased (Table 5 1.4) The p "

of increasing abundance at all stations (Table 5.1-4) agrees with creel census data (Table 5.1- 9) and stari'ding stock biomass data (X'able'5.1-5) and indicates I

that the sauger population in Wheeler Reservoir has increased in recent years.

31 Standing stock data indicate that smallmouth bass reproduction (as estimated by numbers/ha of young fish .in the samples) has decreased sharply since 1971 in two of three coves sampled consistently since 1969 (Table 5.1-6); this decrease appears to be translated into decreased angler harvest (see Table 5.1-10). The reason for the decline are not known; low levels of reproductive success at all three standard coves in 1973 may have resulted from spring floods. The long-term effects of flooding, e.g., siltation or other destruction of spawning habitat, would be expected to be more severe in the coves at TRM 286 and ERM 2.7; these coves would be more directly exposed to high river flows than would the cove at TRM 275, which is located on an embayment. In addition, the cove at TRM 286 is located in a county park; the decrease noted here may partly be due to increased boat traffic and other human activity.

Total, clupeid, and nonclupeid standing stock biomass (Tables 5.1-7 and 5.1-8) show a similar depression in 1973; however, these values have generally increased since 1973 while smallmouth young have increased only at TRM 275.

In contrast to smallmouth, standing stocks of sauger appear to have generally increased for all three age/size groups since 1971 (Table 5.1-5) except in the Elk River. This increase agrees with the increased catch by anglers (Table 5.1-11) and in gill net samples (Table5.1-4). Walleye have not been taken in cove samples in Wheeler Reservoir since 1954.

32 I

An ler harvest of smallmouth bass walle e and sau er Table 5.1-9 presents estimated angler harvest of sauger, based on- a continuous, roving-clerk creel census. Sauger harvest in the areas censused (Figure 5.1-1) is largely concentrated above the plant (areas 1-1, and 1-2, 38 percent of 1t total catch) and in the area below the plant (area 3-1, 31 percent). Area 2-1, which includes the plant and mixing zone, yielded 16 percent of the sauger catch. No census data are available for, the tailwater fishery-at Guntersville Dam, located approximately 30 river miles (48 km) upstream from the plant; the tailwater fishery is highly seasonal and limited to the spawning run (December-February),

,The sauger fishery in the main pool of Wheeler Reservoir appears to

\

be a recent development; prio'r to 1974,. the creel census reported only harvests of 28 sauger in the spiing of 1972 and 21 sauger in the autumn of 1970 (Table 5.1-11). Catches of sauger in Chickamauga (approximately 125 mi or 200 km upstream) have shown the same general increasing trend since 1972 as do those in Wheeler; the magnitude of the-catch in Chickamauga is, however, significantly greater .than for Wheeler (1974, 4,700 vs. 237; 1975, 3,500 vs. 388).

Walleye appear only once (1970 Table 5.1-11) in the Wheeler creel census and only I

rarely in the harvest from Chickamauga (68 in 1972; 137 in 1974). It appears

, that. walleye. are generally not actively sought, but-rather are accidental captures.

Table 5.1-10 presents estimated harvest data for smallmouth bass. Of the smallmouth harvested, 45 percent were taken in area 3-2, 27 percent in area, 4-1 (Elk River),

21 percent in area 3-1, and 7 percent in area 2-1. The concentration of harvest

33 in the lower sections of the reservoir (and Elk River) reflects the distribution of preferred habitat of the species, e.g., rock bluffs, sunken logs, and gravel or rubble substrate.

Since 1970, the harvest of smallmouth has declined appreciably, except for an unusually high harvest in March, 1973 (Table 5.1-11). A similar decline has been noted for Chickamauga Reservoir where harvest has been estimated at V

4,300, 100, 160, and 360 for the years 1972-1975, respectively. The reasons for the decline are not known. Plant operation does not appear to be a factor. For three comparable se'asonal periods (summer, fall, and winter) in 1974-1975 and 1975-1976, the harvest for Wheeler was 556 during startup and operation of units 1 and 2 and 599 after plant shutdown,(see Table 5..1-. 11).

'Angler harvest and has (all species) generally declined since 1972; decline has been noted for Chickamauga; a similar but ~:

from Wheeler Reservoir has been highly variable more regular pattern. of

~ I

'I 'C ES'gQfATED HARVEST.-'-THOUSANDS 1970 , 1971 1972, 1973 .. .1974 . 1975 Wheeler 153 392 550 340 195 286 Chickamauga 289 245 205 185

5.2 Plankton and Benthos 5.2.1 Sam lin Pro ram 5.2.1.1 Pro ram Description A nonfisheries biological monitoring program was ihitiated at the Browns Ferry Nuclear Plant in 1969. Data were and are being collected Sor the phytoplankton, zooplankton, and benthic macroin-vertebrate communities once each quarter at the following locations: (1) Control Stations TRM 307 '2> TRM 301 '6> TRM 295 '7s and (2)

Experimental Stations - TRM 293.70, TRM 291.76, TRM 288.78, TRM 283.94, and TRM 277.98.

5:2,"1.2'. Materials'di The nonfisheries biological monitoring program ik described in the Browns Ferry Nuclear Plant Environmental Technical Specifications. The hionitoring program was designed to determine the effect of the thermal effluent on the reservoir standing crops of phytoplankton, zooplankton,'and benthic macroinvertebrates by comparing population parameters at experimental stations with that for control stations.

5.2.1.3 Results and Discussions The data compiled since 1969 has been summarized in the following reports:

• Tennessee Valley Authority. Water ualit and Biolo ical Conditions in Wheeler Reservoir Before 0"o..ration of Browns Ferr Nuclear Plant 1968-1973. Chatt nooga, Tennessee, March 1974. Report No. M-W(-74-1-BF-l.

35 Tennessee Valley Authority. Water ualit and Biolo ical Conditions in Wheeler Reservoir Durin 0 eration of Browns Fer Nuclear Plant (Unit 1) Au ust 17 1973-Februa 17 1974. Chattanooga, Tennessee, April 1, 1974. Report No. M-WQ-74-2-BF-2.

Tennessee Valley Authority. Water ualit and Biolo ical Conditions in Wheeler Reservoir Durin 0 eration of Browne Ferr Nuclear Plant (Unit 1) Februa 18 1974-June 30, 1974. Chattanooga, Tennessee, August 15, 1974.

Report No. M-WQ-74-3-BF-3, Tennessee Valley Authority. Water ualit and Biolo ical Conditions in Wheeler Reservoir Durin 0 eration of

\

Browns Ferr Nuclear Plant (Units 1 and 2) Jul 1, 1974-December 31 1974. Chattanooga, Tennessee, February 5, 1975. Report No. M-W0-75-1-BF-4.

o'Tennessee Valley Authority. Water alit and Biolo ical Conditions in Wheeler Reservoir Durin eration of Browns Fer Nuclear Plant (Units 1 and 2) Januar I, 1975-June 30 1975. Chattanooga, Tennessee, August 5,.

1975. Report No. M-WQ-75-2-BF-5.

oTennessee Valley Authority. Water ualit and Biolo ical Conditions in Wheeler Reservoir Durin 0 eration of Browns Fer Nuclear Plant (Units 1 and 2) Jul 1 1975-December 31, 1975. Chattanooga, Tennessee, Feb. 12, 1976.

Report No. M-WQ-76-1-BF-6.

36 Tennessee Valley Authority. Water alit and Biolo ical Conditions in Wheeler Reservoir Durin eration of Browns Fer Nuclear Plant Janua 1 1976 December 31, 1976. Chattanooga, Tennessee, March 1977.

Report No. M-EAC-77-01.

These data are summarized and discussed briefly for the three ma)or aquatic communities (i.e. Qhytoplankton, zoo-plankton, and benthic macroinvertebrates).

Ph to lankton The phytoplankton assemblage is diverse (Table 5.2-1) in Wheeler Reservoir with 27 Chrysophyta, 52 Chlorophyta, and 17 Cyanophyta',taxa being documented. The percent composition of the three ma)or phytoplankton groups during the summer quarter at the various stations is presented in Table 5.2.-2.

These data illustrate that blue-green algae (Cyanophyta) do become the dominant (50 percent of the standing crop) group of phytoplankton in Wheeler Reservoir. However, this dominance occurred both upstream and downstream of Browns Ferry Nuclear Plant and also occurred prior to commercial operation of the nuclear plant. Water temperatures at the 1-M depth for the sampling dates are presented in Table 5.2-3, Estimates of the phytoplankton standing crop from 1969 through 1976 are presented in Table 5.2-4. The average stand-ing crop estimates during the five-year preoperational phase indicate that the number of algae cells increases in the downstream reaches of Wheeler Reservoir. Likewise, the

0 CQ

37 .

data for the'operational phase exhibits the same trend; however, the average standing crop estimates for this period are considerably higher than those values from the preopera-tional period. It should be noted that the estimates for the control stations were quite similar.

The biomass of the phytoplankton community was determined indirectly from the Chlorophyll a content of the cells (Table 5.2-5). As with the standing crop, estimates of the biomass increased in the lower reaches of Wheeler Reservoir.

Chlorophyll a biomass levels, also, exhibited the same relationship between the preoperational and operational periods as did the standing crop estimates.

With both phytoplankton standing crop estimates and Chlorophyll a biomass values exhibiting the same trends, it is not surprising to note that primary productivity albo followed the same general trend (Table 5.2-6). However, the magnitude of the variation between the preoperational and operational phases is'ot as large as with the standing crop or Chlorophyll a biomass.

Evaluation of the phytoplankton data indicates that there is a difference (because of the variability within the data set no statistically significant differences can be demon-strated) between the preoperational (1969-1973) and operational I

(1974-1976) years. There were no discernable alterations to the composition of the phytoplankton assemblage (i.e.,

blue-green algae did not tend to comprise a greater percentage of the flora and blue-greens were dominant, also, at one or more of the control stations). However, a consistent increase

38 was documented in standing crop, Chlorophyll a biomass, and primary productivity estimates. These increases are not attributable to the thermal effluent from the Browns Ferry Nuclear Plant since they occurred during periods (summer 1975 and 1976) termed operational; when the plant was not actually operating (i.e., generating electricity and discharging heated water). The data for 1974 were intermediate to the preoperational .and the 1975-1976 data; hence, the operation of one unit at Browns Ferry Nuclear Plant did not affect the phytoplankton community.

The zooplankton assemblage is diverse (Table 5.2-7) in Wheeler Reservoir with 32 Cladocera, 24 Copepoda, and 47 Rotifera taxa represented. There is a distinct increase in the number of zooplankton per unit volume in the lower reaches of Wheeler Reservoir (Table 5.2-8). This increase parallels the pattern described for the phytoplankton in that..the zooplankton populations for 1974 were intermediate to those of the preoperational and 1975-1976 levels. This suggests that one unit operation of Browns Ferry Nuclear Plant does not preclude the maintenance of a balanced and indigenous zooplankton community in Wheeler Reservoir.

39 Benthic Macroinvertebrates The benthic macroinvertebrate community is not overly diverse (Table 5.2-9), but is characteristic of other mainstream, Tenn-essee River impoundments. This type of fauna is typically associated with fine textured sediments with varying levels of organic detritus incorporated into the substrates. The macroinvertebrates have been grouped into four categories for discussion purposes (i.r., ~Hexa enia, Corbicula, Chironcmid

~mid es, and Oligochaetes) .

The burrow1ng mayfly ~Hexa enia b111neata, inhabits soft sediments. This type of habitat is not usually encountered at TRM 301.06 and TRM 307.52 (Table 5.2-10); hence, the reduced population Revels reflect lack of habitat. The largest populations (based on average population estimates) were documented immediately downstream of the Browns Ferry Nuclear Plant thermal discharge. This population distribution was noted for both the preoperational and the operational

phases, Concern has been expressed about the potential effects of thermal plume entrainment on drifting aquatic macroinvertebrates 1

and the eggs of aquatic insects, especially H. bilenata. Plume s

drift studies at Cumberland Steam Plant on Lake Barkley demon-s strated that nymphs of H. bilineata could survive drifting for prolonged periods (up to 4.5 hours5.787037e-5 days <br />0.00139 hours <br />8.267196e-6 weeks <br />1.9025e-6 months <br />) at temperatures of 34e8 a

C (94.6 F) and higher. Recent laboratory studies have documented the H. bilineata eggs will develop and hatch at 34oC (93.2 F)

(Tennessen, Personal communication). From these data and the population characteristics it can be concluded that the thermal effluent from Browns Ferry does not affect the H. bilineata population.

Corbicula manilensis, the Asiatic clam, with the exception of a short initial semiplanktonic stage is fairly sedentary and provides an avenue for studying long-term effects. The maximum populations of C. manilensis were documented within the immediate 1

vicinity of the Browns Ferry Nuclear Plant (Table 5.2-11). This distributional pattern closely parallels that of H. bilineata.

Since C. manilensis exhibits a contagious distribution the variations between the preoperational and operational phases hold no significance. These data indicate that the thermal effluent from Browns Ferry is not affecting the C. manilensis population.

Chironomid midges, depending upon the species, may have two or more complete life cycles during a summer pekkod. Hence, chironomid populations are subject to marked natural variations. I There is a very similar population distribution between the preoperational and the operational phases of the monitoring program (Table 5.2-12). As with the two previous benthic macroinvertebrate populations, the data indicate that the thermal effluent from Browns Ferry Nuclear Plant is not affecting the chironomid midge population.

41 Aquatic o4igochaetes, depending upon the taxon and the abundance, can be classified as nuisance species and/or as indicators of organic pollution. Even though the population numbers have increased (Table 5.2-13) since commercial operation was initiated, the continued abundance of other species and the fact that only a few hundred feet of the.,

bottom habitat is actually contacted by the thermal effluent suggests that the increase occurred coincidentally with the start of commercial operation. Hence, it can be deduced from these data that the thermal effluent from Browns Ferry Nuclear Plant is not affecting the oXigochaetes populations.

The available benthic macroinvertebrate data suggest that the operation of the Browns Ferry Nuclear Plant during 1974 did not affect the maintenance of a balanced and indigenous benthic macroinvertebrate community.

Table 5.1-1 Co:.:.-.:on a'nd 'Scientific"Hamcs<<of I'ishcs taken in prcoperatfonal Sampling, 5,'heeler Reservoir, 1969-1972.

Co:mon Name Scientific Hame T p G 1 Crce1 Heter Hets Hets Census Hctting Paddlcfish ~Pot odon snathula.

Spotted gar I ongnosc Jar Leni'sos tcus osseus. '

X

'hoztnose gar A! X Skipjack herring Al" ~A. *ll X -X X '. X Gi-..sard shad Dozosoma ~cc cdianum ~ X-

~'hzeadAi.n shad Bozo orna '

P X X yr.trncnsc'liodon

(

.'[ooncyc ~tcr,isus A

S'Lonezolloz Camnos tnma anoma1um. ~

X

~

old fish Caresse us auratus X

~

Carp Cv~ri.nns ca~rAio X '

BECcycd chub ~livbo .".is ~asiblo s Sil.vcr chub )IYbnQeis s toreriana I

Golden Shiner HorcsAiconas crysolcccas X X

<<7aken from Common and Scientific Name. of ":f shcs, American Fisheries Society Specfal publfcatjon Ho, Third Ed< tion, 1970;

<<-"1ndicatcs forage, rou"h, or game as arbitrarily indicated for TVA waters,

Table 5.1-1 (continued) (page 2 of 4 pages)

~ Co.::!!on and Scientific Names of Fishes taken in Prcoperational Sampling, wheeler Reservoir, 1969-1972, Com!Aon Name Scientific Name Ro tenone Tr ap Gill Creel Heter Nets Nets Census. Netting Pmcrald shiner ~Notre is atbcrinoidas X Spo t Ein shiner Bluntnose minnow Bullhead minnow River carpsuckcr ~Car ~En'des comic X Creek chubsuckcr ~Brie> ten oblanr us r " X Northern hog sucker Hvpcnleliuai ~nl.ricans Smal lnouth buf Ealo 3:ctiobus bubalus 'X Big.".!outh buffalo Yctiobus tv~a( nc!lus X Black bpfEalo Yctiobua ni",ar Spotted sucker Ninvt.ena ~melano s Silver redhorsc  ? loxos tomn ani'surum River rcdhorse Hoxoscoma carinatum R Black redhorsc 'Hero.".teisn ~du uesnei Golden rcdhorsc 1 for.os tnma ~cr thrurum

~ ~

'le.eiobus sp. - larval fish; . species not known,

Table 5,1-1 (continued) (page 3 of 4 pages) .

Common cnd Scient fic Names of Pishes ta1t:cn in Preopcrational Sampling wheeler Rcservoi, 1969>>1972, Co.-.:non Name Scientific Name Group potcnone T<

lad tom Noiurus op ~ Plathcad'atfish ~Plodicti.s olivcris X Blacks tripe topminnow 7'undulu no ta tus 'P X ~ ~ Hosnuitofish rambusis atii nit pi X Br~ok Sib;crside E.abidcsthcs sfcculus tihi tc bass 1foronc chL~gopg X Yellow bass &lorene sitssissi fcnsis 1>,ocl; bass ~A" '1 ii.i:. G Qzccn sunfish ~ ~ ~7.e omis cvnnellus X"

5. 1-1 (continued)

. t,'p::gc 4 of 4 page ) table tons...on and scientific Names of Pishcs taIcea in Preoperal:ionnl Sampling, Nhaeler Reservoir, 1969-1972. Scientific TraP Qi ll Creel Mc tcr Com!non Name Name Group Rotcnone Nets 'ets . Census Netting [i'a Y!:!Outh ~Ln amis guineas 0'ngcspo t tcd sunfish ~Le amis humilis Bluegill ~l,a pinks mccrachirus. Longcar sunfish o:nis mc niacin ' ~l,e X X Redcar sunfish. X X X Small!I!outh bass llicrontcrus dolomicui .X . X Spotted bass M~icro ~tccuc nunctulatus X X X La<<i,cmouth bass Micron tel un snimcides X Mhite crappie Poa!osis annulnris G DLaclc crappie X X, X V~rter l:.theostoma sp, I,ogperch Porcine charades SavQcr Stfp.ostcdion canadcnse'tirps Malleyc ted(on vitrcum V'i I.r(!lfIll G X -X Prc"'!!~a ter drum AnlchIinntun grunnicns X X Table 5.1-2 Thermal preferenda= of smallmouth bass obtained from three recent- investigations. Acclimation temperature, C 20-24 27 30 Preferred temperature Mean 30.4 day (1) 29.8 night (1) 30.1 (2) 29.7 (3) 31.3 (2) 30.9 (3) '9.4 (3) Range 26.7-34.4 day (1). 25.6-33.9 night (1) 95X confidence limits 28.3-32,2 (2) 29.9-35.1 '(2) 28.5-34.8 (3) 26.7-30-6 (3) 27.7-32.6 (3)

References:

(1) Reynolds 6 Casterlin, 1976; (2) Cherry't al., 1975; and (3) Cherry't al., 1977.

Summary of catch (S). and catch par unit ofort during preoperational monitoring, Browns Perry Nuclear Plant. Data are from gill net catches at Station 1, TRM 293.

t (c/f) for smallmouth bass, walleye, and sauger Autumn Winter S rin Summer Year Species 1 N c/f N c/f c/f N c/f

.1968-69 SMB W

S 0.20 0.05 0.13 3 0.08 1969-70 SMB 0.1Q 0.03 S 0.20 0.08 0.10 1970-71 SMB 3 0.08 W

S 2 0.05 0.10 1971-72 SMB 0.05 W

S 0.05 0.10 1972-?3 SMB W No Data S 0.03 1973-74 SMB 0.05 Q.03 W

S 0.18 0.05 W walleye, Stizostedion v. vf.treum S = sauger, S. canadense s ) 7

~f 7y

Table d Catch Per unit of effort for amallmouth baa catch from gill nets during the operational gMB), aauger riod, Browns (g), and walleye 0(), and Perry Nuclear Plant.

total fi Winter Summer Station Year SNB S Total Station Year SMB S Total 1 74 418 74 0. 05 606 75 308 75 0.11 735 76 0.65 253 76 0.28 897 74 0.08 231 74 85 75 No Samples 0.08 114 76 0.93 433 76 0 03 0 36 179 74 0:. 05 292 ,74 0.03 643 75 76 0.49 0,05 414 151 75 76 0.18 0.65 l,ill 990 S rin Autumn Station Year SMB

' Total Station Year SMB. -

S Total 74 0.03 0.05 985 74 0.05 0.25 342 75 0.11 997 75 0.63 268 76 0.78 1,344 76 2.08 0.03 486 74 0;03 164 7'4 0.28 129 75 0.18 405 75 0.98 273 76 0."35 835 7.6 1.18 323 74 0. 03 686 3 74 a.7a O.O3 822 75 0.40 423 75 0.05 475 76 1.23 829 76 3.45 610 1/ Station 1 - TRM 293 2 - TRM 299 3 TRM 294

Table >-> Numbers (N) and biomass (kg)'f sauger and valleye per hectare taken in cove-rotenone samples, I

5 ~

Wheeler Reservoir. YOY = young of year (<200 mm TL); = intermediate (200-300 mm);

H ~ harvestable,()300 mm). Coves at TRM 275,. 286, and ERM (Elk River) 2.7 are standard sampling coves for preoperational and operational monitoring.

Sau er. YOY Location Year kg N kg TRM 275 1961 3 . 0.14 1970 5 0.13 1971 0.29 1972 5 0.35 1973 16 0.60 1974 5 0.15 0.21 1975 14 0.37 0. 62 0.11 TRM 278 1976

.1950 1951 6

3 9

0.31 0.13

'0.34 3

1

'27

~

0.88 0.04 1952 3 0.49 1 0.32 1953 2 0.11 1 0.13 1 0.38 1954 2 0.09 14 . 1.69 4 1.66 TRM 279 1956 0.32 TRM 280 1976 0.12 14 2.05 TRM 286 1969 1 0.03 1970 18 0.69 1971 1972 1 0.03 1 0.05 1973 9 0,30 0.17 1974 8 0.16 1 0.12 0.28 1975 27 0.74 10 1.56 1976 21 0.99 24 2.48 2.45 TRM 294 1973 0.18

Table 5.1-5 (ccnainned)

Sau er YOY H Location Year N kg kg ERM 2.7* 1974 5 0.17 1975 3 0.06 5 0.59 1976 8 0.77 0.60 ERM 7 ~ 2 1955 0.20 3 0.25 1956 3 0.41 Malle e YOY N kg 'N kg

.TRM 278 1951 0.08 1952 1953 1954 0.34

• No gauger taken in 1969 at TRM 275 and in 1969 through 1973 at ERM 2.7.

Table:. 5. 1-6 Number (N) and biomass t

(kg) of smallmouth bass per hectare taken in cove-rotenone samples,

%heeler Reservoir. YOY = young of year (<125 mm TL); E intermediate (l25-~'mm); H = harvestable

.(>QgOmm)., Coves at..TRM 275, 286, and ERM (Elk River) 2.7 are standard sampling coves for preop'erational and operational monitoring.

YOY H Location Year N kg N kg N kg TRM 275 1961 108 0.41 23 1.70 1969 112 0.29 45 2.91 21 4.63 1970 95 0.36 19 1.02 12 4.66 1971 85 0.86 32 '.35 32 18.69 1972 80 0.64 31 2.56, 17 3.39 1973 36 0.41 7 0.57 8 1.34 1974 1975 146 84 0.$ 7 0.68 ll ll 0.69 0.67 6

3 0.85 0.87 1976 108 1.46 19 0.91 24 3.35 TRM 278 1949'950 47 0.39 13 0.46 3 0.78 28 0.30 6 0.19 7 3.12 1951 14 O.ll 2 0.05 6 4,51 1952 42 .0.43 44 2.01 2 0.37 1953'954 27 0.34 16'4 0.65 12, 2.18 18 0.23 1.62 9 2.00 TRM 279 1956. 16 0.20 28 0.95 0.76 TRM 286 1969 149 0.32 58 0.53 29 1.03 1970 86 0.15 13 0.55 2 0.38.

1971 135 1.13 83 2.36 5 0.71 1972 8 0.05 1 0.09 1 0.18 1973 1 0.01 1974 1 0'01 1975 3 0.04 1976 7 0.10 0.03 1.13 TRM 293 1969 27 0.38 26 0.54 2.93 TRM 294 1973 4.42

Table 5.1-6 (Continued)

YOY Location Year N kg N ERE 2P, 1969 (Elk River} 1970 25 20 0.26 0.21 2

2 0.04 0.23 1971 141 1.31 38 1.01 1972 9 0.10 9 0.75 1973 1974 16 0.13 1975 9 0.10 0.18 1976

53 Table 5,1-7 To'tal clupeid and nonclupeid standing stock biomass (kg/ha) estimated by cove-rotenone samples, Wheeler Reservoir.

Location Year Total Clupeid Nonclupeid TRM 275 1961 190 16 174 1969 965 588 377 1970 1,107 574 533 1971 727 258 469 1972 1,181 830 351 1973 '280 123 157 1974 208 110 98 1975 266 73 193 1976 460 94 366 TRM 278 1949 203 89 114 1950 296 230 66 1951 115 28 88 1952 218 97 121 1953 262 98 164 1954 330 215 115'72 II TBM 279 1956 203 31 TRM 280 1976 733 343 390 TRM 286 1969 441 155 286 1970 759 496 263 1971 569 284 285 1972 561 284'80 277 1973 292 . 212 1974 505 447 58

'1975'976 287 '153 134 1,635 1,400 235 TRM 293 1969 1,534 1,139 395 TRM 294 1973 333 63 2?0 TRM 339.2 1961 242 28 214 ERM 2.7 1969 1,091 401 690 (Elk River) 1970 599 71 528 1971 54.3 108 435 1972 457 184 273 1973 . 364. 73'3

~

291 1974 381 288 1975 405. 54 351 1976 456 60 396

54 (Continued)

Loca tion Year Total Clupeid Nonclupeid ERM 7.2 1955 369 110 259 1956 664 413 251 1957 697 330 36?

1958 745 259 486 1959 642 315 327 1960 1,149 604 545 1961 388 44 345

Table 5.1-8 Means and standard error (gg) of total, clupeid and nonclupeid standing stock biomass (kg/ha) estimated by cove-rotenone samples, Wheeler Reservoir, 1969-1961 and 1969-1976. N = number of eoyes sampled.

Year N Total SgE Cluyeid Nonelupeid SFE 1949 203 89 114 1950 296 230 66

'8 1951 115 88 1952 219 97 121 1953 262 98 164 1954 330 115 215 1955 369 110 259 1956 434 230 293 120 141 110 1957 697 330 367 1958 745 259 486 1959 642 315 327 1960 1,149 604 545 1961 273 30, 244 1969 1,008 225 571 209 437 87 1970 822 150 380 156 441 89 1971 613 58 217 55 396 57 1972 733 226 433 201 300 25 1973 299 34 81 10 218 43 1974 365 86 217 115 148 71 1975 3 319 43 93

~ ~ I 30" 226 '64 1976 821 279 474 315 347 38

5 ] 9 Estimated sauger sport fishing haarest by area, Wheeler Reservoir, April 1973 through June 1976.

Season Areas l-l and 1-2 Area 2-1 Area 3-1 Area 3-2 Area 4-1 Totals No. lb. No. lb. No. -

lb. No. lb. No. lb. No. lb.

1973 Apr << June July - Aug Sept Dec 1974 Jan - Mar Apr June July -

Sept Dec Aug 39 84 31 42 18 13 82 62 14, ll 153 84 117 42 1975 Jan Apr Mar2 June>

July Aug 54 28 '9 85 71 51 10 78 102 336 256 Sept - Dec 52 42 52 42 1976 Jan - Mar3 Apr June 115 '9 107 110 27 286 249

1. Startup, Unit X.--

2. Startup> Unit 2.

3. Plant not operating.

0 Areas 1-1 and 1-2 Area 2-1 Area 3-1 Area 3-2 Area 4-1 Totals Season No. lb, No. lb. No. lb. No. lb. No. lb. No. lb.

1973 Apr June 52 = 620 457 429 149 34 24 1,135 630 July - Aug 139 93 69 53 310 246 98 68 . 616 460 Sept Dec 1974 Jan Mar 34 60 51 56 85 116 Apr June 333 639 24 62 357 701 July - Aug 2 47 88 65 80 112 168 Sept - Dec 9 36 62 32 45 37 b2 114 168 1975 Jan Mar 3 209 .197 lzl 60 330 257 Apr - June 4 77 54 101 60 90 36 126 ?5 394 225 July - Aug 28 17 57 40 26 118 240 96 351 271 Sept .- Dec 4 68 37 68 37 Jan Mar 4 140 1976 Apr - June 4

~

10 10

'310 5 36" 3i 31 20 338 20 509 219 182 311 180 611 217 887 L. Missing data.

2. Startup, Unit 1.

3. Startup, Unit 2.

4. Plant not operating.

Table 5. 1 Estimated smallmouth bass, sauger, and wall e sport-.fishing harvest, Wheeler Reservoir, July 1970 through June 1976.

Smallmouth Bass Sau er ,-.Walle e Season No. lb, No. lb. No. lb.

1970 S 6,424 4,537 F 4,674 4,700 21 48 37 1971 W 101- 133 S 2,505 2,580 S 2, 614 ~

2,579 268 281 1972 W 638 493 S 2,279 1,937.. 28 28 S 850 852-F 156 85 1973 V 5,304 2,061 S 1,135 630 S 616 460 F

1974 W 85 116 S .357 701 S 112 168 153 117 F3 114 168 84 42 1975 330 257'25 S4 394 336 256 S 351 271 4

68 37 52 4

1976 W4 180 217.

611 286 249

'87 S

Total 30,166 24,375 960 742 48

l. Ninety eight percent of the smallmouth caught during the season were taken in March.

2 ~ Startup, Unit 1.

3. Startup, Unit 2.

Plant not operating.

59 Table 5.2-1 LIST OF PHYTOPLANKTON GENERA COLLECTED IN WHEELER RESERVOIR FROM 1969-1976 DURING THE SUMMER SEASON CHRYSOPHYTA Actinella Cyclotella Gomphonema Pinnularia Achnanthes Cymbella Gyrosigma Pyrobotrys Asterionella Denticula Mallomonas Rhizosolenia Attheya Diatoma Melosira Stephanodiscus Caloneis Dinobryon Navicula Surirella Chaetoceros Eunotia Nitzschia Synedra Cocconeis Fragilaria Ophiocytium CHLOROPHYTA Actinas trum Cosmarium Micractinium Selenastrum Ankis trudesmus Crucigenia Oocystis Schroederia Arthrodesmus Cryptomonas Pandornia Staurastrum Acanthosphaeria Dactylococcus Pediastrum Sphaerocystis Botryococcus Dictyosphaerium Planktosphaeria Tetradesmus Carteria Elkatothrix Platydornia Tetraedron Ch 1amydomonas Euastrum Pleodornia Tetrallantos Chlore1 la Eudurnia Polyedriopsis Tetraspora Chodatella Gloedactinium Protococcus Tetrastrum Chlorococcum Gloeocystis Protoderma Treubaria Closteridium Golenkinia Pteromonas Trochiscia Closteriopsis Gonium Quadrigula Ulothrix Coelastrum Kirchneriella Scenedesmus Vorticella CYANOPHYTA Anacystis Aphanizomenon Cylindrospermum Myxosarcina Anabaena Arthrospira Dactylococcopsis Oscillatoria

,Anabaenopsis Chroococcus Gomphosphaeria Phormidium Aphandcapsa Coelosphaerium Merismopedia Raphidiopsis Spirulina

60 Table 5.2-2 PERCENTAGE DIVERSITY FOR kfAJOR GROUPS OF PFIYTOPLANKTON BY RXVER MILE AND- YEAR 1969-1976 SB&lER " BROHNS FERRY NUCLEAR PLANT Preo orational crational TRM 'a'or Grou s 1969 1970 1971 1972 1973 x 1974 1975 1976 x 277.98 Chrysophyta 14 73 31 61 32 42 32 18 29 26 Chlorophyta 30 15 9 22 37 23 49 25 26 33 Cyanophyta 56 12 60 17 31 35 16 56 44 39 t 283.94 288.78 Chrysophyta Chlorophyta Cyanophyta Chrys ophy ta Chlorophyta 12 36 52 37 8

57 18 25 64 14 41 10 49 42 6

64 19 17 71 17 31 34 35 33 25 41 23 35 44 20

'0 30 47 43 26 26 40 34 33 26 37 24 39 35 18 31 31 37 23 22 '. ll 291. 76 Cyanophyta Chrysophyta 55 10 56 '0 52 68 '2 32 34 39 15 53 39 22 47 41 34 39

'4'20 Chlorophyta 25 21 32 21 27 28 .21 25 Cyanophyta 65 54 ll 46 40 15 49 293.70 Chrysophyta 20 75 40 55 19 42 44 28 43 38 Chlorophyta 18 ll 6 31 32 20 35 29 27 30 Cyanophyta 62 14 54 14 49 39 17 41 29 29 295.87 Chrysophyta 8 76 54 51 17 41 30 14 41 28 Chlorophyta 34 7 7 35 30 23 18 30 Cyanophyta 58 17 39 14 53 36 16 60 40 39 301 '6 Chrysophyta Chlorophyta Cyanophyta 14 27 59

'9 39 42 45 49 6

58 24 18 13 28 59'5 34 21 30 39 26 30 28 40 40 28 31 .

33 32 32 307.52 Chrysophyta 12 89 63 67 9 48 11 19 59 30 Chlorophyta 83 6 8 22 37 31 40 35 35 37 Cyanophyta 5 5 29 11 54 21 37 45 ~5 29 a ~ Control stations

61 Table 5.2-3 WHEELER RESERVOIR TEMPERATURE AT THE TIME BIOLOGICAL SAMPLES WERE TAKEN DURING THE SUMMER 1972-1976)

( F AT 1-METER D H)

Date 7/5/72 7/9/73 7/8/74 7/7/75 7/2/76 277.98 79.0 84.1 82.1 83.1 80.2 283.94 79.0 84.2 82.4 82.3 80.2 288.78 78.5 82.8 79.6 81.2 79.9 291.76 78.3 81. 7 80.4 80.6 79.0 293.70 78.4 82.2 81.3 80.8 78.6 295.87 78.0 81.7 78.9 80.3 78.6 301.06 78.1 81.3 79.5 80.3 78.7 307.52 78.1 81.4 78.6 79.9 78.3

62 Tab1e 5.2-4 PHYTOPLANKTON POPULATION BY STATION - SUMMER - 1969-1976)

BROGANS FERRY NUCLEAR PLANT

'Phytoplankters/1, Hean Values x 106) 0 erational TRiiI Pxeopexational 1974 1975 1976 277.98 3.2 4.0 6.7 5.8 5.5 283.94 2.7 4.0 3.5 7.3 4.9 288.78 3.1 3.0 1.5 6.4 3.6 291.76 1.9 2.2 1.5 2.5 2.l 293.70 1.3 1.5 0.8 3.8 2.0 295.87 1.6 1.0 1.3 301.06a 1.2 1.2 0.8 0.9 1.0 307.52 1.2 0.5 0.3 0.2 0.3

a. Contxol stations

63 Table 5.2-5 CIILOROPIIYLL CONCENTRATIONS BY STATION 1969-1976 SUI&IER BRONHS FERRY NUCLEAR PLANT Suriace Ph to lankton Chloro h (Mean Values) ll -'"

erational m Chl /m Prep erational 1974 1975 1976 277.98 6.76 16.22 10.56 14. 66 13. 81 283.94 5.72 16.08 13 F 05 15.60 14.91 288.78 4.26 F 01 4.85 17.01 13.29 291 '6 4.21 6 '9 3 '0 5.24 5.18 293.70 4.53 1.68 2. 15 8.74 4. 19 295.87 3 '7 4.04 1.98 0 81 3. 62 301.06 2 ~ 43 0 ~ 43 1 ~ 81 1.48 l. 24 307.52 1.88 0.43 1.46 1 09 1. 00

a. Control stations

64 Table 5.2-6 1 -1 6 S R "BROWNS FERRY NUCLEAR PLANT mg C/ m2/day Preo erational 0 erational TRM 1972 1973 X 1974 1975 1976 X 277.98 2,202 1,899 2,050 3,784 1,661 2,072 2,506 283.94 2,720 .2,539 2,630 5,496 1,935 2,705 3,379 288.78 1,167 452 810 2,957 887 3,808 2,551 291,76 1,143 227 685 2,491 691 1,271 1,484 293.70 587 157 372 1,872 374 1,926 1,391 295.87 511 220 366 2,129 419 888 1,145 301.06a 445 52 249 li789 294 515 866 307.52a 350 89 220 425 127 156 236

a. Control stations

~~

65 Table, 5.2-7 OCCURRENCE OF 700PLANKTON SPECIES BROILS FERRY NUCLEAR PLANT Tennessee River Nile 278 284 289 292 294 296 301 308 Cladocera Alone sp. 1 2 0 3 3 0 0 0 Alone costata Sara 3 0 0 3 3 0 0' 0 Alone Sut ta 0 0 3 0 0 0 0 2 0 1 1 3 2 1 2

~(

Alonella sp. 0 0 3 0 3 0 0 0 1 1 1 1 1 1 1 0 0 3 0 3. 0 2 1 1 3 3 1 3 3 3

~ ~" ") 0 3

1 0

1 0

1 3

3 0

3 0

0 0

0 0

~Ch dorus sp. 3 1 3 1 1 1 1 1

~Da hnia parvula Fordyce 1 1 1 3 1 3 0 3

~Da hnia poles Leydia 0 0 3 0 3 0 0 0

~Da hnia ratrocurva Forbes 1 1 1 1 1 1 1 1

~Da hnia Selects (Mendotae) 3 0 0 3 0 0 3 3 t

1 1 1 1 1 1 1 1 0 0 0 2 1 0 0 2

~Gaetro us sp. 0 0 0 0 0 0 0 3 1 1 1 1 1 1 2 1 1 1 1 3 1 1 1 2 Latona setifera 0 0 0 0 3 0 0 0

~Le todora Icindtii (Foclce) 1 1 1 1 1 1 1 1

~La di ia uadranularis (Leydia) 3 3 . 0 1 0 3 0 0 Moins micrura Kurz 3 3 3 3 0 3 2 1 Moins minute Ilansen 3 3 3 3 3 3 3- 0 Pleuroxus denticulatus Birds 3 0 0 1 3 2 0 1 Pleuroxus hamulatus Birge 3 0 0 3 3 3 0 0 0 0 0 0 0 0 0 1

") 3 2

3 1

1 1

1 2

1 1

1 1 2

1 1

3 3 3 3 3 3 0 Simo~ce holus votulus Schodler 0 0 2 0 0 0 2 0 Copepoda A~ruins sp. 0 0 3 0 0 0 0 0 0 3 0 0 0 0 0 0 0 3 3 3 3 3 0 3 2 0 0 0 0 2 0 3

~ *. 1 1 1 1 1 1 1 1 CVVclo s varicans rubollus Lilljeborg 0 3 0 0 3 3 3 3

~C clo s vernnlis I'ischer 1 1 1 1 1 1 1 1

~Dig ton>us bir ci Ilarsh 2 0 0 0 0 0 0 0 Dia toison siissz si iensis Marsh 0 0 0 0 0 0 0 2

~ia toinus pnllidds Ilcrrick 1 1 1 1 1 1 1 1

~Dig tonius ~roi hardi Marsh 1 1 1 1 1 1 1 1

s (6

TAble 5.2-7,(continued)

Tenncsscc River Mile 278 284 289 292 294 296 301 308

~Dia tomas ~san uinaus S. A. Forbes 3 1 0 2 3 3 1 0

~Eischura Fluviatilis 0 0 0 0 0 0 0 3

~Er asilus sp. 1 1 1 1 1 1 1 1

~Euc clo s ~lilis (Koch) 1 1 1 1 1 1- 1 1 clo s ~sergius (Lilljeborg).

~Euc i"'"'"""> 0 3

1 0

0 1

3 0

1 0

0 1

3 0

1 0

0 1

0 1

1 0

0 1

Nitocra lacustris Fischer 3 1 2 1 1 1 1 3 0 3 0 0 0 0 0 0 3 3 0 0 0 3 0 0 0 0 0 0 0 2 0 0 Parastenocaris sp. 0 0 0 0 3 0 0 0 1 1 1 3 3 1 1 1 Roti. fera a 1 1 1 1 1 1 1 1 3 0 3 3 0 3 0 3 Brachionus ~an ularis Geese 1 1 1 1 1 1 1 1 Brachionus bennini (Leisslung) 0 0 0 2 0 0 0 0 Brachionus bidentata Anderson 2 3 1 3 1 1 1 1 Brach'ionus buda estinensis Daday 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 Brachionus caudatus Barrois 6 Daday 1 1 1 1 1 1 1 1 Brachionus havanaensis Rousselet 2 1 3 1 1 3 3 1 Brachionus uadridentatus 1Ierman 1 3 3 1 1 3 1 Brachionus rubens Ehrenburg 0 0 0 0 0 0 0 Brachionus urcerolaris Muller 0 3 0 0 3 3 3 3 3 3 3 3 1 3 3 Gollotheca ~ela ica 3 .3 3 3 1 3 1') 1 Conochiloides sp. 1 1 1 1 1 1 1

)- 0 0 0 0 2 3 2 2' Conochilus unicornis Burckhardt 1 1 1 1 1 1 lr Dissotrocha sp. 0 0 0 0 0 0 0 3

~E i hence macroura Barrois & Dodgy 3 3 3 3 3 3 3' 3 Euchlanis s~. 3 1 1 1 3 3 1 Pilinia sp. 1 3 1 '3 3 3 1 1 1lexarthra sp. 1 1 3 3 1 0 0 2 Kellic'ottia bostonicnsis (Roussglet) 1 1 1 1 3 1 Kcratella americana (Ahlstrom) 3 0 3 3 0 3 Keratella cochlcaris (Gosse) 1 1 1 1 3',. 1 Kcratclla cra: sa Ahlstrom 1 1 1 1 1 1 Kcratclla carlina>> Ahls trom 3 1 3 1 1 1 1 Karatella Bundrat'a 0 0 0 0 3 0 0 0 Kerntella ~vol a (Ehrenberg) 0 0 0 0 0 3 Lecane sp. e 0 0 0 3 3I 0 L~a adella sp. 0 0 0 0 0 2 3 "Macrochactus sp. -0 0 0 0 3 0 0 O ~Monost la sp.

l 0 1 0 2 3 1 3

'll

'I

67 Table 5.2-7 (continued)

Tcnncsscc River Mile 278 284 .

289 292 294 29G 301 308

~Honest la crenate liarring 0 0 0 0 0 0 3 0 0 0 0 0 0 0 2 Notholca sp. 0 3 3 3 3 1 3 0

~plat ies Eatulus (Huller) 1 1 3 0 1 3 1 1

~plat ias uadricornis (Ehrenberg) 1 0 0 0 3 0 0 0 sp. 'ipes'orna 1 1 1 1 1 1 3 1 1 1 1 1 1 1 1 1 P~om ~hol x sulcate Hudson 0 0 0 0 0 0 0 3

~Pt ura sp. 0 3 0 0 0 0 0 0 Rocaria ~ne tunia 3 3 3 3 3 3 3 3

~Snchaeta sp. g 1 1 1 1 1 1 1 1 Iestudinella 'sp. 0 3 0 0 0 0 0 0 Irichocorca sp. 1 1 1 1 1 1 1 1 Trichotria sp. 3 3 3 3 1 3 3 1

0. Organism not identified at TRM indicated.

1. Organism identified at T&1 indicated in both preopera'tional and operational moni tor ing.

Organism identified at TRH indicated in only preoperational monitoring.

Organism identified at TRH indicated in only operational monitoring.

s hcrricki.

b. Includes Filinia maior (Celditz) and Filinia ~lon iseta.

c.

e. Includes Lecane a -"""

leontina.

Includes Hexarthra intermedia Wisniewsxi and Hexarthra mire (Hudson).

f. Includes Ploesoma hudsoni (Imhof) and Ploesoma trucantum (Levander).

g. Includes ~Snchaeta ~se late Wierzejsky.

i Pl

68 Tablei5.2-8 ZOOPLANKTON POPULATION BY STATION SUMMER 1973-1976)

BR(MNS FERRY NUCLEAR PLANT Zoo lankton / m 10 P'reo erational 0 erational TRM 1973 1974 1975 1976 x

'h 277.98 19.1 20.8 18.5 35.5 24.9 283.94 10.1 20.4 21 ' 11.5 17 '

288.78 '.7 8.0 2.3 11.4 7.2 291.76 5,4 2.9 3.9 4.1 293.70 2.3 4.0 3.2 9.5 5 ~6 295.87 Q.9 3.3 1.2 9.5 4.7 301.06 0.5 1~9 1.4 8.1 3.8 307.52b 1~3 8 ' 3.6

a. Zooplankton collection methodology was change in 1973 to a bottom to surface vertical tow of a 1/2-m tow net, hence only 1973 preoperational date can be compared to the operational data.

b. Control Station

S Table 5.2-9 BENTHIC MACROINVERTEBRATE TAXA COLLECTED IN WHEELER RESERVOIR BROWNS FERRY NUCLEAR PLANT Annelida Clitellata,(Oligochaetes)

Branchinra ~scwerh i Beddard Arthropoda Insecta Diptera (Chironomid midges)

Chironomus tentans Fabri.eius C tochironomus spp.

Pentaneura spp.

Procladius spp.

Smittia spp.

Xenochironomus festivus (Say)

Ephemeroptera (mayflies)

BBexa Benia hilineata (Say)

Mollusca Pelecypoda Heterodonta Corbicula manilensis Phillipi s

, 70 Table 5.2-10 HEXAGENIA POPULATIONS BY STATIONS SlPBKR BROWNS FERRY NUCLEAR PLANT Hexa enia/m2 Hean Values 0 erational Prep erational 1974 1975 1976 x 277.98 22 121 26 56 283 '4 20 40 83 423 182 288 '8 44 179 300 310 263 291.76 91 173 266 312 250 293.70 72 269 167 151 196 295 '7 13 185 183 177 182 301.06 15 0 307.52 . 0 0 0, 1

a. Control S ta tions

Table 5.2-11 CORBICULA POPULATIONS BY STATIONS BROWNS FERRY NUCLEAR PLANT Corbicula/m Mean Values Preo erational 0 erational All Seasons Summer. Summer 1974 Summer 1975 'Summer 1976 x 277.98 83 91 92 173 97 121 283.94 119 220 133 48 159 113 288.78 209 224 453 195 387 345 291.76 187 169 318 139 264 240 293.70 149 154 288 185 240 238 295.87 108 136 223 131 153 169 301.06 63 26'6 97 56 60 307.52 64 62 52 71 53

a. Control Stations

72 Table 5.2-12 QIIRONOMIDAH POPULATIONS BY STATIONS SlMKR BROGANS FERRY NUCLEAR PLANT Chironomidae/m (Mean Values)

Operational Prep erational 1974 1975 1976 277 '8 97 110 147 113 283 '4 116 110 92 70 91 288.78 75 74 150 90 los 291.76 68 58 92 121 90 293 '0 52 104 36 102 81 295.87 60 18 80 41 301,06 36 13 307.52 43 68 12 42

a. Control stations

'73 Table 5.2-13 OLIGOCHAETA POPULATIONS BY STATION SIGHER BROGANS FERRY NUCLEAR'LANT Oli ochaeta/m2 Mean Values erational 277 '8 115 346 516 276 379 283e94 115 320 409 604 444 288.78 182 545 457 493 498 291 '6 130 442 409 389 413 293 '0 178 527 316 62 302 295 '7a 97 233 147 199 193 301.06 99 134 89 224 149 307 '2 27 66 38 40 48 a', Control s tations

0

~,

Second Ci.

Ant Ca I

VWt(ll +NWNS tlRAY DAM 3'40 245 NSR 2

5 1'5 Sgrlsy Ca 0

WHllllR.RESEAYOIR Figure 5.1-1 Definition of areas sampled in creel census, Wheeler Reservoir.

'5 6.0 Effects of 0 eration at 90 F 32.2 C Maximum 6.1 Fishe Resources The effect of discharging heated water to a maximum of 32.2 0 C will be the avoidance of the mixing zone and the warmest regions of the thermal plume by the more thermally-sensitive species during the periods of highest ambient temperature. Wrenn (1975) noted that skip)ack herring, sauger and walleye avoided the heated effluent of Colbert Steam Plant (Pickwick Reservoir) at temperatures greater than 30 C, while gar, gizzard shad, threadfin shad, carp, bluegill, large-mouth bass and channel catfish were commonly collected in the discharge at maximum summer temperatures (33 -35 C). These results Are in general agreement (discounting differences in thermal history, i.e.,

seasonal acclimation) with those from studies of other steam plants (e.g., Gammon, 1973; Teppen and Gammon, 1976; Yoder and Gammon, 1976) in that many species adjust their distribution relative to the thermal discharge on a seasonal basis. The discharge diffusers at Browns Ferry are located such that there is no possibility of fish becoming trapped in areas of adverse temperatures.

Results of operational monitoring through 1976 (Tables 6.1-1-6.1-4) indicate that, while catch totals occasionally fall outside the ranges (mean + 1 standard error) defined by preoperational sampling, the occurrences cannot conclusively be attributed to plant operation. For example, in winter samples (Table 6.1-1), only catches at Station 2 (above the plant at TRM 299) varied outside the preoperational range; winter samples included one set (1975) under full operating conditions i.e., thermal discharge. Summer operational catches (Table 6.1-3) included a thermal-dishcarge period (1974); the catch at Station 1,.

the thermally-'influenced area at TRM 293 in 1974, was below the

76 preoperational range as mould be expected; so, ho~ever, was the catch at Station 2.

I 6.1.1 Thermal Blocks e of Fish Mi rations One of the possible 'fmpacts of the discharge of a thermal effluent is that of establishing a thermally-enriched zone which could act as to migrating fish species.

a~'arrier Three species present in Wheeler Reservoir are considered- likely to make upstream spawning migrations:

sauger, walleye, and white bass. Migrations of sauger occur from November through April in TVA reservoirs and white bass migrations usually occur from February through April; migrations of the rarely-walleye have not been documented. f'ccurring During TVA's recent 316(a) studies of two steam plants, Bull Run and Cumberland (reports submitted to EPA in 1976), the ability of sauger and white bass to negotiate a thermal discharge during their spawning

-migrations was investigated. Both of these plants have relatively large thermal plumes relative to the dimensions of the receiving waters.

The Bull Run study was performed during December-April 1975 and January-March 1976. Xn the first period phase 203 sauger were tagged and released at least four miles below the plant. Of the 30 sauger which were later recaptured, ll were caught in the discharge basin and four were taken above the plant. None of these fish were recaptured above the plant before the plant experienced a shutdown, but six of the fish did move into the discharge basin and were recaptured while the plant was operating.

During 1976, 56 sauger were tagged and released below Bull Run Steam Plant.

Three of these sauger were later recaptured above the plant before a shut-down occurred. The coldest temperatures in four years were experienced at

'77 this time, and the plant was required to operate near maximum capacity.

It was apparent from this two-year study that the heated discharge from Bull Run Steam Plant posed no significant problem to sauger migrations in Melton Hill Reservoir. Data collected during 1975 indicated that sauger moved into and remained in the discharge while-the plant was operating. Studies conducted during 1976 indicated that the tagged fish apparently had little difficulty continuing their movement past the thermal plume to the colder upper reaches of the reservoir and then returning downstream.

Near the Cumberland Steam Plant 252 sauger were tagged and released below the plant during the period from December 1974 to January 1975.

Nine of the 19 recaptured fish had moved past the plant when at least one of two units were operating. In April 1976, 88 White bass were tagged and released below Cumberland's thermal effluent. Six of these fish were subsequently recaptured upstream of the plant in the vicinity of Cheatham Dam before a shutdown occurred.

The observations from both steam plants studies demonstrate that sauger and whit.e bass can move upstream past, under or through a thermal plume during their spawning migrations. Walleye would also be expected to exhibit the same unrestricted movement past a heated water discharge.

Based on these observations, plus the fact that worst-case thermal con-ditions occur in the suminer, several months after spawning migrations

'have, been concluded, $ t is believed that no thermal barrier to migration will occur with a 90 F maximum temperature limitation.

0 78

6. 1. 2 ~6ammaa

1. Wheeler Reservoir supports a fish fauna typical of southeastern reservoirs; the assemblage of 59 species taken during preoperational monitoring (Table 5.1-1) is largely dominated by clupeids, ictalurids, centrarachids and one sciaenid.

2. Three species have been identified by EPA and the State of Alabama as coolwater species; sauger, walleye and smallmouth bass. The apparent thermal requirements of these species serve as the basis for the present thermal standards applied to the Tennessee River.

3. The distribution of these three species, as indicated by netting and creel census results, in such that they are not abundant in the area likely to be affected by the thermal plume. Sauger are largely t concentrated above the plant; smallmouth bass are concentrated in areas 10 km (6 mi) or more below the plant and in the Elk River.

Walleye are seldom captured by any method, do not contribute significantly to the angler harvest and thus apparently are not an important component of the total fish community of Wheeler Reservoir.

4. Abundance of smallmouth bass, as indicated by creel census, netting and standing stock estimates, appears to be declining while sauger abundance is increasing. Neither phenomenon is attributable to plant operation.

5. Recent laboratory and field investigations indicate that earlier definitions of thermal preferenda and upper lethal temperatures, for the three species of concern, require revision upwards. The:.

classification of smallmouth bass as a "coolwater" species appears

79 to be untenable; in terms of thermal requirements, it does not differ significantly from largemouth bass under similar conditions of acclimation. While sauger and walleye appear to have lower thermal preferenda and upper lethal temperature limits than do smallmouth, recent results suggest that short-term exposures to temperatures, of 30 -32 C would not cause mortality.

6. gauger, smallmouth and walleye are capable of avoiding water temperatures above their preferenda; none of the three is limited by habitat requirements to the area of the mixing zone and thermal plume.

7. No migrating specied will be affected by thermal blockage.

8. Operation of Browns Ferry Nuclear Plant under thermal standards of 32.2C maximum temperature may affect the seasonal distribution of some species, but such operation will not result in any significant adverse impact upon the fisheries resources of Wheeler Reservoii.

80 6.2 Plankton and Benthos Evaluation of the temporary thermal limits is based on the following assumptions:

The commercial operation of the Browns Ferry Nuclear Plant is with Helper Mode cooling during periods when ambient tempera-tures approach or exceed 86 0 F.

o The frequency analysis presented in Section 7, Figure 7.2-2; approximates the conditions that will exist in the future.

o The frequency and duration of the mixed river temperature do not exceed those presented in Table 7.3-1.

o'he maximum temperature discharged via the Helper Mode during a worse case situation cannot exceed 94 0 F.

o The maximum mixed temperature will not exceed 90 F.

Primary concern in the evaluation is for the effects upon the plankton communities (i.e., phytoplankton and zooplankton). As previously discussed in the benthic macroinvertebrate section, this community is not significantly affected since the thermal effluent contacts only a very small area immediately downstream from the diffuser.

The literature contains little specific information on the in situ effects of elevated temperature on zooplankton. Anraku (1974) recognized that increased temperatures could induce changes in

81 zooplankton species composition that may affect the feeding of their 3

predators, especially that of the early development stage of fish, and that increased temperatures could also alter patterns of energy flow. Coker (1934) found that there appears to be a physiological>

difference between copepods reared at low temperatures and those reared at high temperatures.

The frequency and duration of elevated temperatures (Figure 7.2-2 and Table 7.3-1) over ambient conditions under helper mode operation are deduced not to be of sufficient magnitude to significantly affect the zooplankton community. Thus, the operation of the Browns Ferry Nuclear Plant in the Helper Mode of cooling to achieve the proposed thermal limit should not prevent the maintenance of a balanced and indigenous zooplankton community in Wheeler Reservoir.

However, operation under open cycle to achieve the limit would greatly increase the frequency and duration of temperatures at the proposed maximum limit. The extended duration and frequency experienced via

)

open mode co'oling (Figure 7.2-2 and Table 7.3-1) could affect the zooplankton communities .of Wheeler Reservoir.

The phytoplankton community because of the potential for nuisance forms to dominate, and the general nonmotile nature of the organisms, is the principal community in the evaluation of the temporary thermal '

limit. Under natural conditions, one of the main factors in seasonal succession and abundance of species is the different temperature optima of species (Patrick 1974, Hutchinson 1967). As the temperature increases or decreases, species replacement takes place. Temperatures

82 in natural situations in which algal groups exhibit best growth 0

are: diatoms, 18 to 30 C; greens 30 to 35 C; blue-greens, 35 to 40 C (Foerster, et al, 1974); Cairns, 1955; Patrick 1974; Allen Creek Nuclear Generating Station EIS, 1974). Reid (1961),

however, states that blue-greens can predominate in southern temperate aquatic communities when water temperatures exceed 19 0 C.

The seasonal change in floral composition and the dominance of blue-green algae both occur naturally in Wheeler Reservoir, both upstream and downstream from the Browns Ferry Nuclear Plant.

Experimental results (Patrick, 1974) indicate that small heat shocks for very short periods of time may have only temporary adverse effects on some species of algae. Since the frequency and duration of elevated temperatures (Figure 7.2-2 and Table 7.3-1) over ambient conditions are expected to be relatively infrequent and predominantly

of short duration with helper mode operation, it is deduced that the operation of the Browns Ferry Nuclear Plant in Helper Mode to achieve the proposed thermal limit should not prevent the maintenance of a balanced and indigenous phytoplankton community in Wheeler Reservoir. However, operation under open cycle to achieve the limit would greatly increase the frequency and duration of temperatures at the proposed maximum limit. The extended duration and frequency experienced via open mode (Figure 7.2.2 and Table 7.3-1) could affect the zooplankton communities of Wheeler Reservoir.

~ r

~ \

83 FISHERY LITERATURE CITED Brown, B- E- 1962. Occurrence of the walleye, Stizostedion vitreum, in Alabama south of the Tennessee Valley. Copeia 1962(2):469-471.

Cherry, D. S., K. L. Diclcson, and J. Cairns, Jr. 1975. Temperatures selected and avoided by fish at various acclimation temperatures.

J. Fish. Res. Board Can. 32:485-491.

K. L. Dickson, J. Cairns, Jr., and J. R. Stauffer. 1977.

Preferred, avoided and lethal temperatures of fish during rising temperature conditions. J- Fish Res. Board Can. 34:239-246.

Coble, D. W. 1967. Relationship of temperature to total annual growth in adult smallmouth bass. J. Fish Res. Bd. Canada 24:87-99.

Cook, F. A. 1959. Freshwater Fishes in Mississi i. Miss. Game and Fish Comm., 239 p.

Dahlberg, H. D., and D. C. Scott. 1971a. The freshwater fishes of, Georgia.

.Bull. Georgia Acad. Science 29:1-64.

197lb. Introductions of freshwater fishes in Georgia. Bull.

Georgia Acad. Science 29:245-252.

Dandy, J. S. 1945. Fish distribution, Norris Reservoir, Tennessee, 1943.

II; Depth distribution of fish in relation to environmental factors, Norris Reservoir. Journ. Tenn. Acad. Science 20(l):114-1'35.

Dickson, K. L., J. Cairns, Jr., D. S. Cherry, and J. R. Stauffer. 1976.

An analysis of the applicability of EPA's 'draft water-temperature criteria: a site-specific case-history evaluation. p. 316-236 In:

G. W. Esch and R. W, McFarlane (eds). Thermal Ecology XI, ERDA Symposium Series (CONF-750425). Augusta, GA. 1975.

<Emig,. Ji W. 1966. Smallmouth bass., p. 354-365 In: A. Calhoun (ed.)

Inland Fisheries Mana ement. Dept. Fish and Game, State of California.

>Ferguson, R. G. 1958. The preferred temperature of fish and their midsummer distribution in temperate lakes and streams. J. Fish. Res. Bd.

Canada 15:607-624.

Gammon, Jr. P. 1970. Aquatic life survey of the Wabash River with special reference to effects of thermal efflunets on populations of'acro-invertebrates and fish. Report.to Public Service Indiana. 65 p. mimeo.

1973. The response of fish populations in the Wabash River to heated effluents. P. 513-52 Oak Ridge, TN In: D. J. Nelson Proc. 3rd Nat'1. Symposium on Radioecology, USAEC (Conf-710501-)(ad).

• Goodsog, L. F., Jr. 1966. Walleye. p. 423-425 In: A. Calhoun (ed.)

Inland Fisheries Mana ement. Dept. Fish and Game, State of California.

0 84 Crinstead, B. G., 1971. Reproduction and some aspects of the life history, of walleye, Stizostedion vitreum (Mitchell) in Canton Reservoir in Oklahoma. p. 41-51. In: G. E. Hall (ed.) Reservoir Fisheries and Limno~lo Amer. Fish. Soc. Spec. Pub. No. 8.

Hubbs, C- L. and K. F. Lagler. 1958. Fishes of the Great Lakes'Region', Bull.

26, Cranbrook Institute of Science. 213 p.

Jester, D. B. 1971. Effects of commercial fishing, species introductions and drawdown control on fish populations in Elephant Butte Reservoir New Mexico. p. 265-286 In: G. E. Hall (ed.) Reservoir Fisheries and

~Lincoln . Amer. Pish Soc. Spec. Puh. Ho. 8.

Koenst, M. H. and L. L. Smith, Jr., 1976. Thermal requirements of early life history states of walleye, Stizostedion vitreum vitreum and sauger, Stizostedion canadense. J. Fish. Res. Board Can. 33:1130-1138.

Neves, R. J. 1975. Factors affecting fry production of smallmouth bass Fish; Soc. 104:83-87.

Niemuth, W., M. Churchill, and T. Mirth. 1962. The walleye, its life, history, ecology, and manage'ments Pub. No. 227. Mis. Cons. Dept. 14 p.

• Priegel, G. R. 1969. The Lake Winnebago sauger. Age, growth, reproduction, food habits, and early life history. Tech. Bull. No. 43., Dept. Nat.

Resources, State of Wisconsin, 63 p.

1970. Reproduction and early life history of the walleye in the Lake Winnebago'egion. '

Tech. Bull. No. 45, Dept. Nat. Resources, State of, Wisconsin, 105 p.

Regier, H. A., V. C. Applegate, and R. A. Ryder. 1969. The ecology and management of the walleye in western Lake Erie. Great Lakes Fish.

Coom. Tech. Rep. 15. 101 p. t Reynolds, W. M. and H. E: Casterlin. 1976. Thermal preferenda and behavioral

.thermoregulation in three centrarchid fishes. p. 185-190'In: G. M..Esch and R. W. HcFarlane (eds). Thermal Ecology II, ERDA Symposium Series (CONF-750425). Augusta, GA. 1975.

e

+Smithp L L p Jr >

and M. H: Koenst. 1975. TemPerature effects on eggs and fry of percoid fishes. Ecological Research Series, EPA-660/3-75-017.

U.S. Environmental'rotection. Agency. .91 p.

Smith-Vaniz, W. F. 1968. Freshwater Fishes'of Alabama. Agr. Exp. Sta.,

Auburn Univ., 211 p.

'I Teppen, T. C. and J. R. Gammon. 1976. Distribution and abundance of fish populations in the middle Wabash River. p. 272-283 In: G. W. Esch and R. W. HcFarlane (eds). Thermal Ecology II, ERDA. Symposium Series (CONF-750425). Augusta, GA. 1975.

(

o 85 Trautman, M. B. 1975. The Fishes of Ohio. The Ohio State University Press, 683 p.

Wrenn, W. B. 1975. Seasonal occurrance and diversity of fish in a heated discharge channel, Tennessee River. Proc 29th Ann. Conf. S.E. Assoc.

Game and Fish Comm: 235-247.

1976. Temperature preference and movement of fish in relation to a long, heated discharge channel. p. 191-194 In: G. W. Esch and R. W. McFarlane (eds). Thermal Ecology II, ERDA Symposium Series (CONF-750425). Augusta, GA. 1975.

Yoder, C. 0. and J. R. Gammon. 1976. Seasonal distribution and abundance of Ohio River fishes at the J. M. Stuart electric generating station.

p. 284-295 In: G. W. Esch and R. W. McFarlane (eds). Thermal Ecology ERDA Symposium Series (CONF-750425).

II, Augusta, GA. 1975.

86 PLANKTON'&:BENTHOS LITERATURE CITED Allen Creek Nuclear Generating Station. 1974. Final Environmental Statement for Units 1 and 2. Houston Lighting and Power Company.

Section 5.5.2.1.1.

Anraku, M. 1974. "Review, Warm Water Effluents and Plankton." Bull.

Plantkton Societ of Ja n. 21(1):1-31.

Cairns, J. 1955. "The Effects of Increased Temperatures Upon Aquatic Organisms." Pardue Universit En . Bull. 40.346.

Coker, R. E. 1934. "Reaction of Some Freshwater Copepods to High Tempera-tures." J. Elisha Mitchell Scientific Soc. 50:143-159.

Foerster, J. W., F. K. Trainor, and J. D. Buck. 1974. "Thermal Effects on the Connecticut River: Phycology and Chemistry." J. Water Poll.

Contr. Fed., 46(9):2138-2152.

Hutchinson, G. E. 1967. A Treatise on Limnolo . Volume II Introduction to Lake Biolo and the Limno lankton.,'John Wiley & Sons, Inc., New York, 1115 pp.

Patrick, R. 1974. "Effects of Abnormal Temperatures on Algal Comminities."

In: Thermal Ecolo . Edited by J. W. Gibbons and R. R. Sharitz, U.S.

Atomic Energy Commission, pp. 335-349.

Reid, G. K. 1961. Ecolo of Inland Waters and Estuaries. Van Nostrand Reinhold Co., New York, 375 'pp.

Tennessen, K. J. Biologist TVA Water Quality and Ecology Branch, Muscle Shoals, Alabama. Personal communications.

Table 6;.1-1

SUMMARY

OF MINTER QUARTER GILL NET SAMPLING PREOPERATIONAL (1969-1973) AND OPERATIONAL (1974-1976)

. c/f STATION SE -

v wt SE' c/E wt. kg. c/i'

- preoperational (means) 10.046 4.632 3.502 1.915 1 >> operational 1974 418 10,450 165.53 4.138 1975 308 8.105 137,46 3,617 1976 253 6,325 . 90.09 2.252 2 <<preoperational (means) 10.087 1.168 3.848 .607 2 - operational 1974 231 6,417 96.03'.668 1975 NO SA%'LE 1976 151 3.775 47.15 1.179 3 - preoperational (means) 8.138 4.063 3;089 '1.548 3 - oPerational 1974 292 7. 300 124. 41 3.110 1975 414 10. 615 161. 95 4.153 1976 433 10.825 134.62 3.364

0 Table 6.1-2

SUMMARY

OP SPRING QUARTER GILL NET Sf&PLING PREOPERATIONAL (1969-1973) AND OPERATIONAL (1974-1976) c/f .

STATION x wt . SE N c/f wt. kg. c/f 1 preoperational (means) 18.827 3.919 6.049 '800 1'- operational 1974 985 24.625 269.18 6.730 1975 997 26.237 285.57 7.515 1976 897 22.425 240.70 6.017 2 - preoperational (means) 11.815 3;810 3.613 .977 2 <<operational 1974 164 4.100 92.37 2 309 1975 405 10.125 87.35 2.184 1976 179 '.424 82.26 2.493 3 - preoperational (means) 22.977 16.520 5.878 3.438 3 - operational 1974 686 22. 867 158. 61 5.287 1975 423 10.575 96.33 2.408 1976 990 24.750 272.47 6.812

Table 6-1-.3 SMEARY OF SUMMER QUARTER GILL NET SAlPLING PREOPERATIONAL (1968-1972) AND OPERATIONAL (1974-1976) c/f STATION xN ~ x wt SE N c/f wt. kg. c/f 1 - preoperational'means) 29.42 6.34 8..29 1.90 1 - operational 1974 316 7.90 101.75 2,54 1975 735 19.'34 164.56 4.33 1976 897 22.43 240.70 6.02 2 preopera tional (means) 23.18 14.64 3.'44 1. 27 2 - operational 1974 85 2,83 64.82 2.16 1975 114 2.85 45.46 1.14 1976 179 5;42 82.26 2.49 3 - pzeoperational (means) 41.90 11.X5 9,77. 3.25

' - operational 1974 643 16,08 174,92 4.37

. 1975 .1,111 27,78 178.01 4.45 1976 '90 24.75 272.47 6.81

0 0

SUMMARY

OF Table 6.1-4'r FALL QUARTER GILL NET SAMPf,ING PREOPERATIONAL (1969-1972) AND OPERATIONAL (1973-1976) k c/f STATION xN x wt SH N c/f wt. kg. c/f 1 preoperational (means) 9,88 1.53 2.80 0.37 1 - operational 1973 476 11.90 166.22 4.16 1974 252 8.55 138.97 3.47 1975 268 6.70 94.28 2.38 1976 486 12.15 178.74 4.47 2 - preoperational (means) 7'.98 1;87 3.16 .64 2 - operati'onal 1973 169 4.23 96.72 2.42'974 i

129 3.23 43.62 1.09 FQ 1975 237 5.93 89.55 2.24 1976 323 8,08 126.07 3.15 3 >> preoperational (means) 18.10 9.73 7.01 2;37 3 - operational 1973 304 7.60 117,60 2.90 1974 822 20.55 246.78 6.17 1975 475 11.86 159.73 3.99 1976 610 . 15.25 253.58 6.34

91 7.1 Condenser Coolin S stem 0 erational Modes The condenser cooling system for this plant is designed to operate A

in three cooling modes: Open, Helper and Closed. In the Open Mode,"

the plant pumps 4350 cubic feet per second (cfs) of water from the river through the steam'condenser where the cooling water is heated approximately 25 F before being discharged through submerged, multiport diffusers on the riverbed (Figure 7.1-1). When operating in the Helper Mode, the condenser cooling water is routed to cooling towers before being dis-charged through the three submerged diffusers. In the Closed'ode,;-

the cooling tower effluent is routed into the plant intake channel for reuse as condenser cooling water.

The mixed temperature in the river downstream of the plant depends upon the performance of several subsystems of the plant cooling system.

The temperature increase through the condenser depends upon the flow rate through the condenser and the megawatt generation of the plant, The cooling tower effluent temperature is primarily a function of the wet bulb temperature in the air and the temperature of the hot water from the condenser. The mixed temperature of the river downstream of the plant depends upon the flow rate and the temperature of both the thermal discharge and the river.

Because of unanticipated deficiencies in tower system performance, the system is not providing the heat removal capacity previously expected.

These deficiencies have necessitated significant power reduction during the summer months of 1977. During this period, ambient river temperatures have consistently approached or exceeded the maximum thermal standard (86 F).

>><< "~ +V, >> '<

> >> "$f '92 An analysis of plant-induced, downstream temperatures with the plant operating in Open and Helper Mode cooling during the months of June through September is presented. For this evaluation the plant was ~ assumed to generate at the three-unit design capacity except in certain cases when the effluent temperature at design capacity would 0 have exceeded 94 F. The 94 F temperature had been established as an operating limit to assure that the 95 F design value inlet temperature for certain plant auxiliary systems was not exceeded. A statistical analysis, based upon several years of record, is presented to evaluate the maximum temperatures expected during an average year. Severe conditions were determined by performing a simulation of plant-induced mixed temperatures using recorded meteorology, the river flows and temp-eratures during the summer of 1969. The predicted decay of plant-induced heating at various river miles downstream of the plant is also presented. 7.2 Mixed River Tem erature Probabilities An analysis has been performed to pro)ect the frequency distribution of the mixed river temperature for the summer months of June, July, August, and September. "Mixed river temperature" (T ) is defined here as the temperature of the mixed effluent and river water at the end of the diffuser mixing zone (several hundred feet downstream of the ',1 diffuser as'llustrated in Figure 7.2-1). For an assumed river river flow in the temperature and case of Open Mode cooling, and additionally, for *a wet bulb temperature in Helper Mode cooling, the mixed river temperature can be calculated. Calculations for each month are based on approximately 3000 values of river temperature and wet bulb temperature. ln all cases, the plant load was assumed 93 constant at 3150 MW; the probabilities were calculated for Open and Helper Modes of operation. The results of the analysis are given in Figures 7.2-2 and 7.2-3 which are histograms showing the percent probability that the mixed river temperature will occur in a given temperature range. Plant-induced temperatures during July are pre-dicted to be the most severe, whether the plant is operated in Helper or Open Mode. This analysis reveals that during Helper Mode operation, the plant will rarely,, if ever, exceed a mixed temperature of 90 F. Operating in Open Mode, the mixed temperatures are more severe and will exceed 90 F'nless plant generation is reduced during extreme ambient conditions. 7.3 Simulation of Extreme Condition The simualtion of the plant cooling system throughout a warm summer was performed to provide an indication of the duration of long periods of extreme conditions. The summer of 1969 was previously the year during which the warmest r'iver temperatures were recorded. River temperatures recorded during the summer of 1977 are similar to 1 or slightly warmer than. those recorded in 1969, both being several degrees above normal. River flows were slightly less than normal during those months. The year of 1969 was, therefore, chosen to represent severe summer conditions. The data required to perform this simulation included (1) tri-hourly wet bulb temperatures recorded by the U.S. Weather Service in I Huntsville, Alabama; (2) hourly river temperatures recorded at a depth of five feet in the edge of the river channel slightly down-stream of the present location of the diffuser; and (3) hourly flow releases of upstream (Guntersville) and downstream (Wheeler) hydroelectric plants. These data were used to compute the plant-induced temperature rise (oT) and the downstream mixed temperature (T ). The computer program utilized (1) condenser heat exchange rates recorded at the Browns Ferry Nuclear Plant; (2) dooling tower performance curves determined from tests conducted during the spring of 1977 which reflect approximately 80 percent of design performance; and (3) diffuser-induced mixing theory verified by field tests conducted in June 1977. The plant was assumed to generate at capacity except at those times when it was operated in the Helper Mode and the tower effluent exceeded 94 F. During such times the plant capacity was reduced such that the cooling tower effluent did not exceed 94 F. Table 7.3-1 represents the number of occurrences and the duration of the mixed temperatures exceeding various levels when the plant was operated with the Helper Mode and actual river flows. This table demonstrates that, when operating under these conditions, the 0 plant may exceed the current river maximum temperature of 86 F for two or more consecutive days, but the plant never exceeded 0 90 F or 95 a plant-induced rise of 5 F. The maximum mixed temperature pre-0 dicted under these 'flow conditions was 89.4 F on July 7, 1969, and the maximum plant-induced temperature rise was 4.7 F predicted for September 24, 1969. Also shown in Table 7.3-1 are the times and duration of reduced operation that would have been required in order for the cooling tower effluent not to 0 exceed 94 F. The largest megawatt reduction was 796 megawatts on July 7, 1969. The number of occurrences and duration of mixed temperatures exceeding a specified limit with the plant operating in Open Mode and using actual river flows are presented in Table 7.3-2. Also shown are the number and durAtion of temperatures exceeding a plant-induced rise of 5 F. These results indicate that temperatures are considerably warmer when operating in the Open Mode than those for the Helper Mode. The maximum predicted temperature was 93.2 F and the maximum plant-induced temperature rise of 8.0 F. The principal results from the simulation of June through September of 1969 are summarized in Table 7.3-3. 7.4 Far Field Anal sis of Diffuser Dischar e The changes in downstream reservoir temperatures caused by the diffuser discharge were calculated using the one-dimensional, steady-state, heat transfer equation. Figure 7.4-1 shows the downstream temperature rise predictions for river flows of 10,000, 30,000, and 50,000 cfs and initial mixed temperature rises at the diffuser of 1-5 F. Greater downstream surface heat losses are shown for lower river flows because the travel time to points downstream is longer. However, the initial mixed temperature rise at the diffuser is higher at lower river flows than at higher river flows, as indicated in the near field analysis. The river flow of 30,000 cfs is typical of daily average river flows during the summer months. This'analysis, combined with the results of the simulation of 'extreme conditions with the plant operating in Helper 1fode, indicates that the maximum temperature in the downstream portion of 0 the Wheeler Reservoir is approximately 89 F. 97 TABLE 7.3-1 FREQUENCY AND DURATION OF COMPUTED ELEVATED MIXED RIVER TEMPERATURES 'DURING 1969 HELPER MODE COOLING AND ACTUAL RIVER FLOHS Mixed Tem erature Duration of Load Reduction Period - Hrs >86 >87 >88 >89 dd d dd 1 12 12 12 2 2 2 4 5 3 3 4 3 5 2 5 1 5 6 1 6 1 1 7 1 8 9 2 1 10 1 3 ll 12 '3 1 1 14 15 1 16 1 17 18 1 19 1 1 20 1 1 1 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 or more 8 2 g8 . TABLE 7.3-2 FRE(FLUENCY AND DURATION,OF COHPUTED ELEVATED t1IXED RIVER TEMPERATURES DURING 1969 OPEN NODE COOLING AND ACTUAL RIVER FLOllS Duration of'ixed Period - flrs >86 >87 >88 Tem >89 erature >90 >91 >92 >93 AT>5 F 1 ll 20 16 17 7 5 3 5 2 6 4 7 3 6 3 5 1 7 3 3 8 4 2 5 ~ 7 1 3 4 6 3 4 6 7 3 9 5 ~ 5 1 2 3 4 15 6 5 2 4 1 1 22 7 P 2 2 1 2 12 8 1 ,1, 2 2 1 15 9 3 1 2 5 1 1 12 10 3 4. 3 ll 4 4 3 1 4 2 3 '2 12 2 3 1 1 13 3 . 1 3 2 14 2 2 15 1 3 1 16 2 1 1 1 17 18 19 3 1 20 1 1 21 22 1 1 1 23 1 26 27 28 29 30 31 32 33 34 35 36 37 38 39 1 2 40 .41 42 43 ,1 4g 1 45 1 1 46 1 47 48 or more 19 10 6 1 99 TABLE 7.3-3 SUlji'PRY OF RESULTS OF SIt1ULATIOH FOR JUi'lE-SEPTEMBER 1969 T' 86 > 88 T >90 m m / Time Yiean I Time Mean X Time bean ~brs ~hrs. hrs. He1per 21 18 14 0 0 Open 50 20 27 12 P L NP P ~ ~ ~ ~~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ j ~ ~ ~ FLOW ~ ~ UNIT 3 UNIT I UNIT 2 PP P 9O P Wr"..'~.'-ii~rry~~"::i:~ ~:: p PP OPP p PP P p pp ppI 0 gY p P+>pc> ppap >C CV ~PP0+ P 0 p Ppp P P ~ ..; (I;p, .. ~ .'. 'EcTloii A-A 2 DIA. (6) HOLES g 6 'O.C. KP"".I'~i" '9 ".;:::.:PP:. P 3 ~ ~ ~, 0 0 O O 0 0 0

." "'::::'::::::-'i I'lllLE 293:'::::::-:::::':: ~"::::-'::.:: 'RONNS FERRY 0 0 0 0 0 0 0 0 0 0 0 0 0

2" DIA. (7) HOLES~., C; p6 0 VIEN B-B ~ ~ ' ~ ~ ~ ~ -'.:: ."-:'.-: DIFFUSFRS I ~ ~ ~ HOLE PATTERN ~ ', kf'.'..' ~ ~ ~ ~ ~~ ~ ~ ~ ~ ~ ~ ~~ ~ ~ ~ ~ ~ ~ ~~ ~~ ~ ~ ~ ~~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~~ ~ .~ . lz.l., PTUg ".PUil ~ ~ ~ I ~~ ~ ~ ~ ~ ~ ' \~ ~~ ~~ ~~ ~~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~~ ~ ~ ~~ ~~ ~ ~ ~ ~ ~ ~ + ~ ~ ~ ~ ~~ ~ ~ ~ ~ '~ ~~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ' ~ ~ ~ ~ ~ ~ OVERBANK ~" ~ ~ ' . ':I -" --: i~ihlLE 295<*--'v- ~ . ~ '- ~ - ~ ' "-.. ~ -~ .'"' . - ~ ~ ' ~ ~ ~ ~ ~~ ~ ~ ~ ~ ~ AREA ~ ~ ~ ~ ~ ~ ~ ~~ ~ ~ ~ ~ ~ ~ ~ ~ \ ~ ~~ ~ ~ ~ ~ ~~ ~ ~ ~ ~ ~ ~ ~ ~ ~ + ~ ~ ~ ~ ~ ~ ~ ~ ~ I ~ ~ ~~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ + ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~~ ~ ~~ ~ ~ ~ ~ ~ ~ ~ ~~ ~ ~ ~ ~~ ~ ~ ~ ~~ ~ ~ ~~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ', ,' ', ~ ~ ~ ~~ ~ ~ ~ ' ' ~ ~ ~ ~ ~ ~ ~ ~ ', e ~ ~ ~ ~ ~ ~ ~ ~ ~~ ~ ~ ~ ~ ~ ~ ~ ~ )~ ~ ~ FIGURE 7.l-l: Brogans Ferry Submerged Diffuser, Description and Location M TR QR Tp /Pl/A/V =~//=iI( Qp HELPER 'p + 90 F OPEN: To = Ta + 25.'F >>GU~ 7 2-> Schemafic of Diffuser induced Mixing 0 102 Ipp 99.6 100 80 80 78.1 JUNE JULY 60 60 40 20 20 I I. 2 7.1 43 2.8 0.3 0.1 0 0 <86 86-87 87-88 88-89 89-90 >90 <86 86-87 87-88 88-89 89-90 >90 0 TEMPERATURE RANGE, 'F Ld 0 Ipp IOO 96. 8 LLI I- 91 LLI 80 80 CI Ld AUGUST SEPTEMBER >C 60 60 CI bl I-C3 hJ D 40 0 4 O ~O 0 20 20 6.6 2.6 18 03 <86 86-87 87-88 88-89 89.90 >90 <86 86-87 87-88 88-89 89-90 >90 TE MPE RATURE RANGE, F >>GURE I 2-2 Pro'ected Mixed Rfver Temperature Frequ: ncy Analysis 103 IOO IOO 89.5 JUNE J ULY 80 80 .43.5 LLI CL 40 40 hJ I-bJ 20 20 C9 I 4.6 I 4.2 I l.6 S.l 5.2 ld I.5 P.4 P I CL 0 0 < 86 86-87 87"88 88-89 89-90 >90 <86 86-87 87-88 8S-89 89-90 >90 TEMPERATURE RANGE, F 43 CL ljJ IOO ioo I-0 AUGUST SEPTEMBER bJ CL 80 80 >C CI 60 60 bJ I-Ld 45.9 O CL 40 CL U O ~O 20.8 0 20 I 5.4 20 I 0.7 9.3 6.8 3.2 4.4 0.9 0 i, <86 86-87 87-88 F9=0~ 89-90 >90 <86 86-87 87-SS 88%9 89%0 >90 i-.'MPERATURE RANGE, F FIGURE 7.2-3 Projected Mtxed R>ver Temperature Freque,.cy Ana1ysls Qp = IO,OOO cfs 0 4 0 5 UJ QR= 30,000 cfs CO 4 hJ CL I- 'K Ld LLJ I CI UJ OC 0 QR = 50,000 cfs ASSUMPTION S K= II5 btU ft -day-4F 0 294 290 286 282 278 274 TENNESSEE RIVER MILE 10$ 8.0 Power Su 1 Situation For the remainder of the 1977 summer peak period and extending into the summer peak periods of 1978 and 1979, TVA's power supply situation is expected to be tight. Even with the Browns Ferry Nuclear Plant operating at full output, TVA will be relying heavily upon neighboring utilities for emergency assistance. The following table shows the expected deficiencies for the summer peak periods of 1977-79 with the Browns Ferry plant at full output. These margins represent approximate megawatt deficiencies of 1,500 MW in 1977, 1,300 MW in 1978, and 800 MW in 1979 below the level that TVA deems adequate for a reliable supply of bulk power. DEFICIENCIES BELOW DESIRED RESERVES SUMMER PEAK PERIODS Deficiencies Period 1977 July- 639 August 536 September 1,524 1978 Juhe Jugy 252 August 107 September 17323 1979 June 490 July 627 August 850 September 246 Any reductions in the output from the Browne Perry plant will increase the above deficiencies, increase the risk that TVA will be unable to fulfillits power supply obligations to its customers, and increase TVA4s reliance upon neighboring utilities for assistance. Since most of the utilities surrounding TVA are ~ummer peaking systems, the availability4 of purchase power in large blocks is very uncertain; and, if it is available, the price of purchased power will likely be very high. Increased cost incurred because of purchase power to offset the reductions in the Browne Ferry Nuclear Plant output will result in an increase in rates to the consumer. With median 96 P temperatures, the river temperature often exceeds the 86 P maximum. TVA has been forced to reduce output of the Browne Perry plant some 1,500 NW or more because of the 86 F maximum or 5 F rise thermal standard. Increased system operating cost associated with these reductions have been as high as $ 40,000 to $ 50,000 per hour. Por the three-week period ending July 16, 1977, the total estimated cost of Browne Ferry power reduction has been approximately $ 12.0 million. Unsuccessful efforts to.overcome deficiencies associted with reductions inthe Browns Ferry plant output could result in reductions of firm load. Such reductions could be reflected in systematic reductions in the region's industrial and commercial'oads and possibly to the residential consumers, resulting in economic penalties to the.region's industrial operations as well as to the employees of such industries and to the general populace, Further, since the TVA system operates as a part of an interconnedted network covering essentially the entire eastern United States, such reductions in capacity on the TVA -ystem could affect the reliability of a large part of the Nation's power supply. l