ML062510051

Report 30, Ecological Studies of the Connecticut River, Vernon, Vermont, January - December 2000

ML062510051
Person / Time
Site:	Vermont Yankee File:NorthStar Vermont Yankee icon.png
Issue date:	04/30/2001
From:	Normandeau Associates, Vermont Yankee
To:	Office of Nuclear Reactor Regulation, Vermont Yankee
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Text

Ecological Studies of the Connecticut River Vernon, Vermont Report 30 January - December 2000 Aý Veirtovil Va'nker' I I, it it moit it A z-:, ve ia Iv,:

ECOLOGICAL STUDIES OF THE CONNECTICUT RIVER VERNON, VERMONT REPORT 30 January - December 2000 VERMONT YANKEE NUCLEAR POWER CORPORATION Brattleboro. Vermont Prepared by:

Vermont Yankee Nucleat Power Station PO Box 157 Brattleboro. VT 05354-0157_-.

And NORMANDEAU ASSOCIATES INC.

25 Nashua Road Bedford. NH 03110-5500 APRIL 2001

TABLE OF CONTENTS Page

1.0 INTRODUCTION

............................................................................................................ 1 2.0 COMPLIANCE WITH THERMAL STANDARDS ........................................................ 2 2.1 THERMAL STANDARDS ................................................................................ 2 2.2 METHODS OF DEMONSTRATING COMPUIANCE .................................... 3 2.3 THERMAL IMPACT ........................................................................................ 4 3.0 WATER QUALITY ......................................................................................................... 12 3.1 COPPER. IRON AND ZINC CONCENTRATIONS ......................................... 12 3.2 WATER TEMPERATURE .............................................................................. 13 4.0 MACROINVERTEBRATE COLLECTIONS ................................................................ 28 4.1 METHODS OF COLLECTION AND PROCESSING .................................... 28 4.1.1 Dredge Collections ......................................................................... 28 4.1.2 Macroinvertebrate Rock Basket Collections ................................. 28 4.2

SUMMARY

................................................................................................... 29 5.0 FISH COLLECTIONS .................................................................................................... 40 5.1 METHODS OF COLLECTION AND PROCESSING .................................... 40

5. 1.1 Electrofishing - General Sampling .................................................. 40 5.1.2 Electrofishing - Anadromous Fish ................................................... 40 5.1.3 Impingement .................................................................................. 40 5.1.4 Larval Fish ..................................................................................... 41 5.1.5 Scale Samples for Age Determination ............................................ 41 5.2

SUMMARY

...................................................................................................... 41 5.2.1 Fish - Trapnets, NPDES General Electrofishing, and Impingement ...... 41 5.2.2 Anadromous Fish Electrofishing .................................................... 42 5.2.3 Ichthyoplankton ............................................................................. 43 6.0 2000 ZEBRA MUSSEL AND ASIATIC CLAM MONITORING ................................. 59 6.1 METHODS OF COLLECTION AND PROCESSING .................................... 59 6.1.1 Laboratory Identification Procedures .............................................. 59 6.2

SUMMARY

...................................................................................................... 60 7.0 LITERATURE CITED ................................................................................................... 61 i

LIST OF FIGURES Page 2-1. Vermont Yankee Power, 2000 ............................................................................................. 6 2-2. Vermont Yankee Plant Discharge Flow, 2000 ...................................................................... 7 2-3. Connecticut River discharge, 2000 ....................................................................................... 8 2-4. Simulated Connecticut River temperature increase at Monitor 3, 2000 ............................... 9 2-5. Hourly average Connecticut River temperatures at Monitor 3 and Monitor 7, 2000 .......... 10 3-1. Vermont Yankee NPDES sampling stations ...................................... 14 3-2. Connecticut River water concentrations of copper observed in monthly samples from the vicinity of Vermont Yankee, Vernon, Vermont .............................................................. 15 3-3. Connecticut River water concentrations of iron observed in monthly samples from the vicinity of Vermont Yankee, Vernon, Vermont ........................................................... 16 3-4. Connecticut River water concentrations of zinc observed in monthly samples from the vicinity of Vermont Yankee, Vernon, Vermont .............................................................. 17 3-5. Fishway temperature, 2000 ................................................................................................. 18 4-1. Vermont Yankee NPDES sampling stations in the Connecticut River near Vernon, Verm ont .................................................................................................................................. 39 ii

LIST OF TABLES Page 2-1. Daily and Monthly Average Connecticut River Discharge (CFS) At Vernon Station D uring 2000 ............................................................................................................................... 11 3-1. Summary of 2000 Monthly Connecticut River Water Concentrations of Copper (Cu),

Iron (Fe), and Zinc (Zn) Observed at Vermont Yankee Monitoring Stations 3, 7, and Plant D ischarge .......................................................................................................................... 19 3-2. Daily and Monthly Average Connecticut River Temperature (*F) at Station 7 During 2000 ....20 3-3. Daily and Monthly Average Connecticut River Temperature (*F) at Station 3 During 2000 ....21 3.4 Hourly and Daily Average Temperature at the Vernon Station Fishway During 2000 ...... 22 4-1. Checklist of Macroinvertebrates Collected from the Connecticut River Near Vernon, V ermont in 2000 ......................................................................................................................... 31 4-2. Composition of Macroinvertebrates Collected by Ponar Grab in 2000 Downstream and Upstream of Vernon Dam ........................................................................................................................... 36 4-3a. Composition of Macroinvertebrates Collected by Rock Baskets in 2000 Downstream and Upstream of Vernon Dam ..................................................................................................... 37 4-3b. Composition of Macroinvertebrates Collected by Rock Baskets set in May, July, & August 2000 at Upstream Stations Only .................................................................................................... 38 5-1. Checklist of Fishes (AFS 1991) Collected During 2000 ..................................................... 44 5-2. Catch per unit of effort (CPUE) for electrofishing and trapnetting in the Connecticut River in the vicinity of Vernon, Vermont for Section I of the NPDES Permit in 2000 ........................... 45 5-3. Number and weights of adult and juvenile fishes collected in the Connecticut River upstream and downstream of Vernon Dam in 2000 ........................................................................... 46 5-4. Numbers and weights of fishes captured upstream of Vernon Dam in 2000 in impingement, general electrofishing and trapnets ....................................................................................... 47 5-5. Numbers and weights of fishes captured downstream of Vernon Dam in 2000 in general electrofishing and trapnet programs ...................................................................................... 48 5-6. Monthly impingement of fish on Vermont Yankee's circulating water travelling screens in 2000

.................................................................................................................................................... 49 5-7. Age-specific length and weight statistics for random subsample of white perch collected in 2000

...................... ***** .. ***..*....

.. *** *.* ................................................

50 iii

LIST OF TABLES CONTINUED Page 5-8. Age-specific length and weight statistics for random subsample of smallmouth bass collected in 2000 .......................................................................................................................... 51 5-9. Age-specific length and weight statistics for random subsample of largemouth bass collected in 2000 .......................................................................................................................... 52 5-10. Age-specific length and weight statistics for random subsample of yellow perch collected in 2000 ........................................................................................................................ 53 5-11. Age-specific length and weight statistics for random subsample of walleye collected in 2000 ....................................................................................................................................... 54 5-12. Summary of 2000 Anadromous Fish Collections by electrofishing for American shad at Stebbins Island, Station 3, and 0.1 Mile Below Vernon Dam ......................................... 55 5-13. Vermont Yankee Ichthyoplankton Sampling Effort in 2000 ................................................. 56 5-14. Collection Dates and Total Number of Ichthyoplankton Collected Near the Vermont Yankee Intake in 2000 .......................................................................................................... 57 5-15. Ichthyoplankton Density per 100 Cubic Meters at Vermont Yankee Intake by Depth in 2000 ....................................................................................................................................... 58 iv

1.0 INTRODUCTION

This report is submitted on behalf of the Vermont Yankee Nuclear Power Corporation, and fulfills the requirements of the Final Discharge Permit #3-1199 (NPDES number VT0000264).

This is the fifth annual report submitted under the five-year discharge permit issued in 1996.

Presented in this report are the results of the monthly thermal compliance monitoring and the methods and results of the environmental monitoring program, including water quality, macroinvertebrates, fish, and zebra mussels. The NPDES permit environmental sampling stations referred to in this report are presented on the NPDES sampling stations map (Figure 3-1).

This report was produced as a collaborative effort on the part of Vermont Yankee and Normandeau Associates.

One special study was conducted during 2000 and was submitted to the Environmental Advisory Committee in January 2001 as Draft Analytical Bulletin No. 76. The bulletin was titled "Abundance of Juvenile American Shad in the Vernon Pool During 2000" (Normandeau 2001).

1

2.0 COMPLIANCE WITH THERMAL STANDARDS 2.1 THERMAL STANDARDS The operational mode of Vermont Yankee's cooling water system is related to calendar dates and ambient Connecticut River water temperatures as specified in Vermont Yankee's discharge permit (Permit No. 3-1199, NPDES Number VT0000264) effective 21 March 1996. During the 16 May through 14 October period of each year, Vermont Yankee is permitted to discharge heat to the river within the following thermal standards (A.6.b of the NPDES permit):

Connecticut River Temperature Calculated Increase in River at Station 7 (T7) Temperature above Ambient T7>63 0 F 2 0F 630FaT7>59OF 3 0F 59 0 F>T7>550 F 4 0F 55 0F>T7 5 0F During the period of 15 October through 15 May of each year, Vermont Yankee is permitted to discharge heat to the Connecticut River within the following thermal standards (Section A.6.a of the NPDES permit):

1. The temperature at Monitor Station 3 during open cycle operation shall not exceed 65OF

2. The rate of change of temperature at Monitor Station 3 shall not exceed 5°F per hour, and,

3. The increase in temperature above ambient at Monitor Station 3 shall not exceed 13.4 0 F.

The river discharge near Vernon is regulated by Vernon Dam Hydroelectric Station to remain at or above 1250 cubic feet per second (cfs) or inflow if less than 1250 cfs. Since the theoretical maximum increase in temperature due to Vermont Yankee's thermal discharge at a river flow of 1250 cfs is 12.9 *F, these standards, in effect, permit open cycle condenser cooling without cooling tower operation when ambient river temperatures are less than 52.1 *Fduring 15 October through 15 May. If ambient river temperatures are greater than 52.1 *F, the amount of heat discharged to the river can be reduced by using the cooling towers if the river flow is low.

2.2 METHODS OF DEMONSTRATING COMPLIANCE Compliance with the criterion that limits open cycle operation to times when the downstream temperature is less than 65*F was demonstrated by examination of Connecticut River temperature and plant operating data. Rate of change of temperature is defined in the NPDES permit as the 2

difference between consecutive hourly average temperatures. Measurements recorded in the Connecticut River below the Vernon Dam (Station 3) were used to calculate these differences.

Increase in temperature above ambient is defined in the NPDES permit as a plant-induced temperature increase as calculated by equation 1-1 in the report 316 Demonstration (Binkerd 1978, Downey and Binkerd 1990). This equation is based on the principle of conservation of energy, a principle which is integral to the computer simulation of the Vermont Yankee/Connecticut River system. Using measured upstream river temperature, plant operating data and core thermal power, the amount of heat discharged to the river was calculated. Then, using thermodynamic and hydrodynamic principles and river discharge information, the mixed river temperature increase was calculated and compared with thermal standards.

Equation 1-1, rearranged for ease of computer computation using input from the plant environmental thermal sensor network, is as follows:

Equation 1: DELTA _T = (H _RIV + H _TOWER)/Q Equation la: H_TOWER=(TCITT.I-TCITT)*472727.3/3600 Equation Ib: HRIV = (267.38 *CWPT) * ((TCOr - TCIT) - (CWBPI/CWPT)*

(TCOr (TETOr+ TWTOr)/2)))

where, DELTA _."T = hourly simulated Connecticut River temperature increase at Station 3 in °F H _RIV = caloric heat content of the cooling water discharge HTOWER = caloric heat content of the circulating water system and cooling towers Q = hourly Connecticut River discharge (cfs) observed at Vernon Dam TCIT.j =condenser inlet temperature in °F at time interval t-I TCO = condenser inlet temperature in OF at time interval t CWPT = number of circulating water intake pumps operating in time interval t CWBPT = number of cooling tower booster pumps operating in time interval t TCOTr = condenser outlet temperature in *F at time interval t TETOr = east cooling tower outlet temperature in *F at time interval t TWTOTr = west cooling tower outlet temperature in °F at time interval t Vermont Yankee implemented a design change during the month of May, which linked the Azonics temperature monitoring systems at Stations 3 and 7 to the plant process computer. This allowed Vermont Yankee operators to utilize real time accurate temperature data for thermal compliance. It also allowed Vermont Yankee Environmental Group an opportunity to generate thermal compliance reporting. The WaDaR units remain in the river at Stations 3 and 7 as the back-up temperature recorders to the Azonics. The simulation is based on electronically acquired five-minute river discharge data from the Vernon Dam and Vermont Yankee's five minute observations of thermal temperatures at Stations 3 and 7 and thermal heat discharge to the river.

3

2.3 THERMAL IMPACT Figures in this section illustrate the principle of conservation of energy as applied to the Vermont Yankee/Connecticut River system. Figure 2-1 depicts core thermal power produced by Vermont Yankee in 2000. This data was obtained from one minute and five minute records supplied by Vermont Yankee. The licensed maximum reactor core thermal power is limited to 1593 megawatts.

About one-third of this power was converted to electrical power, while the remainder was transferred as heat to the atmosphere via the cooling towers, or discharged to the river (Figure 2-2).

The plant shutdown on September 13, 2000 at 16:35 due to a reactor scram caused by the loss of the Steam Jet Air Ejectors. The plant startup was initiated after the incident was investigated. The plant reached 100% power on September 16,2000. Otherwise the plant remained at full power throughout 2000, with occasional brief periods of power derating.

Figure 2-3 is a plot of hourly Connecticut River discharge for the Vernon Hydroelectric Station Dam in Vernon, Vermont during 2000. The hourly average Connecticut River discharge was computed using one-minute or five minute observations obtained by Vermont Yankee through their computer system from sensors installed at the Vernon Dam. When the flows were above 32,000 cfs this data was obtained from hourly logs obtained from records at Vernon Dam.

Table 2-1 lists the average daily and monthly Connecticut River discharge computed from the hourly observations obtained for 2000 as described above. For discharge greater than 12,000 cfs, a rating curve was used by Vernon Dam to convert stage height to discharge. The rating curve was the same one used by the USGS prior to abandoning the Vernon gaging station (Aquatec 1995). This curve is believed to be sufficiently accurate because backwater from the Northfield Mountain Pump Storage Facility and the modification at Turners Falls Dam have had little impact on stage height near Vernon Dam during times of high discharge (Aquatec 1995). Below 12,000 cfs, discharge data were obtained from turbine rating curves at Vernon Station. The peak Connecticut River daily average flow for 2000 was 57,943 cfs, which occurred on 05 April 2000. The second highest peak daily average flow (other than in April) was 55,115 cfs on 18 Deeceember 2000. The hourly average flows are represented in Figure 2-3. The peak hourly average Connectcuit River flows occurred on 05 April 2000 at 59,550 cfs and on 18 December 2000 at 59,533 cfs. The lowest flows at Vernon Dam were 1250cfs to 1275 cfs observed for one or more hours during 16-23 July 2000.

The simulated increases in Connecticut River temperature at Station 3 due to Vermont Yankee's operation are plotted for each hour of operation in Figure 2-4. Vermont Yankee's discharged heat remains dependant upon reactor power and plant operational mode. During normal full power operations these values range from 1035 to 1081 mwt. Connecticut River discharge (Figure 2-3),

Vermont Yankee daily average discharge flow (Figure 2-2) and river temperature increase (Figure 2-

4) illustrates that for a constant heat rejection rate to the river, the temperature increase is inversely proportional to the river discharge. Vermont Yankee's operation remained at or below the permit standards for all of 2000 except in July when there were two instances where the Vernon Dam went to minimum flow. All their generators tripped off line due loss of off-site power caused by a lightening strike. The plant operators took prompt action to mitigate this event and began shifting to Recirculation Gate Position and going to Closed Cycle. These events were:

16 Jul 2000 2200-2259 DST +2.74degrees F (above permit limit) Permit Limit + 2.0 degrees F 21 Jul 2000 1900-1959 DST +0.03 degrees F (above permit limit) Permit Limit + 2.0 degrees F During the cold water period when the permit limit was 13.4*F, the maximum simulated river temperature increase observed was 12.6TF on 26 November 2000 at 0700 when the river flow was low at 1275 cfs 4

Hourly average temperatures are measured at Station 7 and Station 3 are plotted on Figure 2-5.

Station 7 is well upstream of the plant, and water temperatures there were unaffected by the plant's thermal discharge. Heat discharged from the plant was well mixed at Station 3, due to passage through the Vernon Dam. Temperatures measured at Station 3 reflected both the natural and plant-induced changes in temperature between the upstream and downstream locations, and never exceeded the 651F during the periods of I January through 15 May 2000 and 15 October through 21 December 2000 (Figure 2-5). At no time during the month did the temperature change observed at Station 3 exceed the +/-5"F permitted change per hour.

5

Figure 2-1 Vermont Yankee Core Thermal Power mwth, 2000 1800 1600 v

1400 IF-1200 1000 800 600 400 200 0 ..........V

...........

.................

..................

...........

January March may Jun August October c V December Day of Year 6

Figure 2.2 Vermont Yankee Plant Discharge Flow 600 500 400-0 300-200--

100 I

0 1 31 61 91 121 151 181 211 241 271 301 331 361 January March May June August October December Day of the Year 7

Figure 2-3 Hourly Average Connectcut River Flow Rate for the Year 2000 80000 70000 60000 50000 dS

"* 40000 0

ic 30000 20000 10000 0

0 50 100 150 200 250 300 350 January March May June August October December Day of Year 8

Figure 2-4 Hourly Average Connectcut River Temperature Increase at Monitor 3 for the Year 2000 14 12 10 0-%

8 Ea 1!

6 4

2 uI'l IflIIMI 0

0 50 100 15U2020300 3

January March May iS une 2 August 250 October De~%ber Day of Year rermineo Lum ueria 1 9 - Calculated DeltaT

Figure 2-5 Hourly Average Connectcut River Temperature at Monitors 3 &7 for the Year 2000 90 80 70 IL C"

,60 0.

E I--

50 40 30 0 50 100 150 200 250 300 350 January March May June August October December Day of Year , p 1. ~ I MnolnlUr 7 tup reamI 10 Monitor 3 (downstream)

Table 2.1 - Average Connecut River DIscharge (aft)at Vernon Station for the Year 2000

....... Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Day 1 8646.17 5378.49 25505.55 31906.96 21250.86 10990.06 2572 20922 3808 1865 3962 8969 2 3984.73 4309.16 17522.57 27749.88 18205.41 9871.95 3117 14617 2694 2489 2997 7992 3 5137.43 6314.67 16631.31 27024.26 18362.55 8429.89 2815 9802 2011 2908 2834 7205 4 9888.03 5508.89 18195.75 46055.21 17663.38 7621.88 2463 8165 1715 3216 2108 9677 5 24771.53 2618.30 14480.80 57942.72 18061.81 7672.20 3359 5652 2338 2331 2074 5729 6 20415.50 2161.59 14097.10 54261.08 16798.92 9218.53 3519 5591 3217 2588 5170 5670 7 14982.50 3204.72 11954.72 44979.13 17135.89 22361.44 4858 7151 3802 4965 4865 4822 8 11585.48 4732.09 12234.08 35361.81 17770.60 16502.21 3575 9047 1600 4482 6277 4098 9 11045.12 5073.63 15110.72 38734.13 18832.48 12293.81 2719 8052 1600 3814 7883 3648 10 11912.75 6231.38 31495.46 51590.92 27179.42 10256.54 6028 9099 1857 3712 9103 2953 11 15953.66 4019.79 31743.68 50899.46 38570.83 9222.08 6629 7745 2528 5343 10146 2324 12 17771.48 3242.44 25537.82 41622.38 43607.13 8570.83 5998 11222 3108 4342 9567 4471 13 14314.70 1993.56 22268.76 33261.42 42544.79 9192.43 6102 8143 2884 5988 10087 5500 14 9697.79 4505.32 17007.04 27568.70 41702.92 9005.68 2892 7379 3228 2581 9351 4795 15 9479.48 5524.83 17588.01 27091.15 40507.88 9727.47 2312 6445 3873 1845 9802 4434 16 5523.28 5340.00 21933.16 29085.98 34419.54 11239.84 6571 7183 3262 4379 10823 3225 17 7804.69 5093.50 29408.67 24842.49 24719.49 7802.42 20035 8874 5081 4880 11268 12982 18 7813.68 5047.28 18644.93 25050.08 21736.22 6878.78 18136 6918 5385 5974 11058 55115 19 9028.08 4684.52 17621.17 22940.88 25459.38 M833.14 11228 6570 6293 9107 9851 45611 20 8840.67 3152.39 15812.55 22092.05 27688.88 9015.48 6833 4873 6151 6903 9391 39166 21 7561.60 3935.71 17178.89 24312.80 22225.48 6321.41 5493 6384 6197 7149 9786 29287 22 7219.06 5344.65 17849.55 31119.94 20154.54 7532.35 4922 3832 3583 4237 7249 23829 23 7976.78 4227.57 21787.01 35099.20 16832.15 5734.02 3944 4979 1778 5602 4531 16182 24 6252.33 4536.25 25786.37 36930.21 17043.75 3120.85 4918 3158 2553 4074 3507 10895 25 5182.17 5350.24 28463.92 35031.25 22510.19 3098.53 3265 6471 3695 6510 3200 8343 28 8148.69 9316.98 29393.14 31648.76 20303.18 6910.47 2233 4839 3570 8232 3440 6434 27 7556.54 10958.99 29238.38 30289.69 16723.69 8848.18 3838 4777 3980 3817 9766 8077 28 7723.87 16859.77 38470.50 29483.27 15719.93 9791.48 3955 4427 3284 1910 8331 7840 29 6683.79 31973.00 47637.50 27133.15 12185.15 7322.35 1828 2503 1851 2889 9874 8531 30 5677.41 47159.13 20527.83 14172.52 3560.68 4521 3930 2170 5604 7723 7516 31 5738.37 42381.00 12330.07 10340 3923 4274 6863 Monthly Avg 9751 6228 23811 34047 23232 8892 5527 7170 3293 4438 7191 12005 11

3.0 WATER QUALITY 3.1 COPPER. IRON AND ZINC CONCENTRATIONS Beginning in April 1996, and continuing through 2000, monthly grab samples of Connecticut River water from Stations 3, 7, and the plant discharge (Figure 3-1) were analyzed for total copper, iron, and zinc, as outlined in the NPDES permit #3-1199. Results of the analysis are presented in Table 3-1 and Figures 3-2, 3-3 and 3-4.

Copper concentrations were observed at or below the detection limit of 0.010 mg/l in nearly all months of 2000 at Connecticut River water sampling Station 7 and in the Vermont Yankee discharge (Table 3-1, Figure 3-2). The highest concentration of copper observed at Station 7 was 0.0202 mg/i on 13 December 2000. The highest concentration of copper observed in the Vermont Yankee Station discharge was 0.0134 mg/l on 17 July 2000. Connecticut River water sampling at Station 3, below the Vernon Dam tailrace, had slightly higher copper concentrations during most of the 2000 sampling events, with a maximum copper concentration of 0.0577 mg/I observed on 13 March 2000 (Table 3-1, Figure 3-2).

Station 7 had relatively high iron concentrations during July and December 2000 (Table 3-1, Figure 3-3). Station 3 exhibited relatively high iron concentrations (> 1.000 mg/I) during the March, May, June and July 2000 sampling events, while Iron concentrations were relatively low throughout 2000 in the Vermont Yankee Station discharge. The highest concentrations in Vermont Yankee Discharges occurring in May and July sampling events. The highest iron concentration of 12.20 mg/i was observed at Station 7 on 13 December 2000. The highest iron concentration at Station 3 was 5.799 mg/i observed on 17 July 2000. The highest iron concentration in the Vermont Yankee Station discharge was 4.951 mg/I observed on 17 July 2000.

Zinc concentrations in Connecticut River water samples were generally less than 0.020 mg/l during 2000. (Table 3-1, Figure 3-4). The highest zinc concentration at Station 7 was 0.141 mg/I observed on 16 March 2000.The highest zinc concentration of 0.0537 mg/l was observed at Station 3 on 15 May 2000. The highest zinc concentration in the Vermont Yankee discharge was 2.07 mg/I observed on 16 March 2000, the next highest value occurring on 15 May 2000 equalling 0.0247 mg/l.

A possible explanation for the variability in the results is that turbulence, associated with sampling methodolgy, rain storms and other high flow events, is also a factor which re-suspends sediments and increases the sediment concentration in the samples. Turbulent flow through the Vernon Dam and power station during high flow events may also re-suspend river sediments, contributing to the high metals concentrations generally observed at Station 3 (below the Vernon Dam) compared to Station 7 (upstream) or the Vermont Yankee discharge.

3.2 WATER TEMPERATURE Water temperature was measured continuously in the Connecticut River at Station 7 and Station 3 during 2000, and at the Vernon Dam fishway during fishway operation. Daily and monthly average temperature data for Station 7 and Station 3 are summarized in Tables 3-2 and 3-3 and were discussed in Section 2.3; the hourly average temperature data for both stations are plotted on Figure 2-5. Hourly and daily average temperature data from the fishway are presented in Table 34 and Figure 3-5. The fishway operated daily from 22 May at 0800 DST to 13 July 2000 at 0900 DST.

During this 2000 period of fishway operation, the water temperatures increased from an hourly average of 52.7°F at the beginning of operations up to a high of 78.95°F to 04 July 2000 at 1500.

13

0 I 2 0

q i I

ii I 2I Mile I

N Vernaz D=m Figure 3-1. Vermont Yankee NPDES Sampling Stations.

14

Figure 3-2 Conneticticut River Water concentrations of Copper observed in monthly samples in the vicinity of Vermont Yankee, Vernon, Vermont 0.14 0.12 0.1 E

0.08 1 Station 7 E Station 3 I-o Discharge o 0.06 0.04 0.02 0

0ý14e 064re.

Irsp 4e CO'ý(e Date I5

Figure 3-3 Connecticut River Water concentrations of Iron observed In monthly samples, from the vicinity of Vermont Yankee, Vernon, Vermont 14 12-10 S8-4-

2-0-

cii Izl CI 1

p rk/ 6 ' IS Date 16

Figure 3-4 Connecticut River Water concentrations of Zinc observed in monthly samples from the vicinity of Vermont Yankee 2.5 2

1.5 U

• Station 7 1 E Station 3

• Discharge 0.5

- -

0 ~a. -. p 0

N/

0 e0 0ý4

/ N N Date 17

A I

i70 60 40 30.

20 10 l9Jun 28Jun 3Jul l1Jul 17Jul 22May 29May 5Jun 12Jun Date FIGURE 3-5. VERNON DAM FISWAY TEMPERATURES, 2000.

18

Concentrations of Copper (Cu), Iron (Fe) and Table 3-1. Summary of the 2000 Monthly Connecticut River Water Zinc (Zn) observed at Vermont Yankee Monitoring Stations 3,7 and Plant Discharge.

NPDES River Water Metals .l).

Station 7 Station 3 Discharge Copper Iron Zinc Copper Iron Zinc Date Copper Iron Zinc 0.117 0.35 0.017 0.01 0.212 0.017 01/13/2000 <0.01 0.231 <0.01

<0.01 0.053 0.267 <0.01 <0.01 0.227 0.018 02/16/2000 <0.01 0.248 0.034 1.08 0.015 0.01 0.476 2.07 03/16/2000 <0.01 0.654 0.141 0.0051 0.852 0.0103 0.0055 0.632 0.0114 04/13/2000 0.0016 0.501 0.0099 0.011 0.0276 4.42 0.0537 0.0075 1.04 0.0247 05/15/2000 0.0047 0.512 0.0057 0.0539 1.18 0.031 0.0037 0.225 0.0079 06/14/2000 0.0025 0.537 0.0157 0.0283 5.799 0.0298 0.0134 4.95 0.0211 07/17/2000 0.0079 4.44 0.0104 0.0052 0.507 0.0117 0.0059 0.532 0.0189 08/14/2000 0.0053 0.556 0.0068 0.0119 0.299 0.0141 0.0046 0.147 0.006 09/01/2000 0.0017 0.178 0.0075 0.0577 0.388 0.0319 0.0056 0.219 0.0055 10/16/2000 0.0037 0.265 0.004 0.0247 0.473 0.0108 0.009 0.288 0.0118 11/14/2000 0.0049 0.281 0.0568 0.0044 0.205 0.0048 0.0051 0.220 0.0239 12/13/2000 0.0202 12.200 Detection Limits for Total Cu, Fe and Zn are 10 ppb.

January to March river water samples were analyzed by Endyne Inc. of Wlllston, VT. Laboratory Detection Limits for Total Cu=O.g ppb, Fe=21.8 ppb and Zn--0.4 ppb.

April to December river water samples were analyzed by RECRA of Lionville, PA. Laboratory 19

7 for the Year 2000 Table 3.2 - Average Connecut River Temperature (deg F) at Station Jun Jul Aug Sep Oct Nov Dec

, Jan Feb Mar Apr May Day 68.67 72.06 59.39 46.62 37.82 34.24 33.58 33.37 38.35 46.32 59.63 70.80 1 72.49 59.12 46.50 37.33 33.57 33.43 39.56 46.83 60.89 70.74 67.04 2 34.32 72.50 59.24 46.18 36.94 33.52 33.43 39.95 47.69 61.66 71.33 66.78 3 3423 59.40 46.19 36.33 40.47 49.38 62.09 71.71 66.49 72.36 4 34.16 33.58 33.46 35.16 72.04 66.71 71.47 59.06 46.13 5 34.14 33.60 33.44 39.86 50.84 62.31 72.48 67.70 70.45 58.55 45.33 34.61 6 33.91 33.65 33.57 39.15 5225 61.25 72.56 68.38 69.80 57.73 45.85 35.02 7 34.01 33.59 33.60 39.01 53.74 58.08 72.39 69.63 69.09 56.74 46.52 35.37 8 34.09 33.57 33.83 39.85 55.20 57.41 57.90 71.80 70.29 68.65 55.49 46.58 35.55 9 34.23 33.52 34.15 41.50 56.69 71.60 70.88 68.71 54.45 46.93 35.74 10 3427 33.48 34.68 40.33 57.09 58.76 71.34 71.77 68.81 53.93 46.73 35.61 11 34.30 33.64 34.41 39.16 54.29 60.56 70.76 71.10 69.31 53.66 46.99 35.45 12 34.51 33.72 33.87 3921 52.06 61.33 70.94 69.64 69.52 53.19 46.90 35.30 13 34.05 33.58 34.04 39.57 51.06 60.73 71.22 68.86 69.34 52.96 46.24 35.00 14 33.82 33.63 34.79 40.45 51.88 60.25 71.78 68.37 68.91 53.74 45.88 35.14 15 33.74 33.65 35.56 41.83 52.67 59.05 59.48 70.14 69.15 68.27 53.89 45.87 34.84 16 33.73 33.83 38.13 4420 5223 61.13 69.00 69.38 67.55 53.76 45.22 34.67 17 33.82 33.64 35.99 45.12 52.81 .33.86 62.34 69.48 69.05 66.99 53.89 43.54 18 33.89 33.54 34.94 44.85 53.63 62.74 69.37 68.81 66.87 52.95 42.54 3428 19 33.77 33.55 34.99 44.19 53.64 63.96 68.34 68.94 66.99 52.49 41.86 34.11 20 33.78 33.68 35.53 43.53 52.54 68.09 68.45 66.64 52.29 41.14 34.07 21 33.74 33.61 36.51 43.88 51.99 65.22 6821 68.48 66.05 51.59 40.40 34.04 22 33.73 33.61 37.77 43.34 51.60 65.74 66.20 68.71 67.86 66.15 50.62 38.99 34.10 23 33.65 33.60 38.83 42.57 51.84 68.95 67.92 65.60 50.55 37.97 34.02 24 33.68 33.59 39.94 41.93 52.76 66.61 66.98 69.62 67.88 64.93 50.54 3722 34.01 25 33.65 33.53 40.12 42.30 54.04 69.81 68.57 63.80 51.02 36.83 34.07 26 33.64 33.50 40.26 4328 54.77 68.12 69.08 69.49 68.95 62.93 51.51 36.72 34.01 27 33.62 33.52 40.27 42.90 55.59 68.95 69.76 62.43 51.27 36.77 33.90 28 33.62 33.48 40.41 43.30 56.57 69.78 69.15 7024 61.01 49.61 36.44 34.05 29 33.60 33.42 3926 43.57 56.92 70.70 69.38 70.55 60.18 47.90 36.99 34.04 30 33.55 38.56 45.28 5728 71.05 69.82 71.27 47.57 33.86 31 33.60 40.05 58.31 63.03 70.32 68.95 67.66 53.81 43.13 34.91 33.91 33.58 36.10 41.75 53.05 Monthly Avg 20

the Year 2000 Table 3.3 - Average Connecut River Temperature (deg F) at Station 3 for Jun Jul Aug Sep Oct Nov Dec I Jan Feb Mar Apr May Day 70.78 74.57 62.26 51.28 39.12 35.01 33.04 38.58 47.72 62.87 75.25 1 34.86 75.17 62.19 50.58 38.72 35.73 33.35 40.01 48.58 64.47 75.50 69.58 2 36.15 74.74 61.86 51.11 38.29 34.68 33.4 40.59 49.66 65.59 75.34 69.42 3 36.43 75.26 61.51 51.68 37.24 34.53 33.42 40.75 51.49 66.12 75.54 69.94 4 34.56 73.30 60.71 53.37 36.94 36.74 33.54 40.15 53.27 65.73 76.24 69.49 5 33.29 72.53 60.52 50.09 36.20 37.18 33.68 39.42 54.77 64.59 76.02 69.59 6 33.04 71.67 60.98 48.39 35.76 33.25 36.65 33.84 39.35 56.59 60.25 75.72 70.99 7 71.02 59.58 48.86 35.65 35.41 34.02 40.25 58.19 59.14 75.05 72.72 8 33.42 71.02 58.28 48.79 36.34 35.15 34.06 41.74 59.68 60.25 74.94 73.60 9 33.54 57.22 48.78 37.01 34.48 40.84 59.32 61.78 75.13 73.98 71.46 10 33.56 34.31 48.27 37.84 39.53 55.88 63.79 74.80 74.73 70.96 56.25 11 33.6 35.32 33.86 36.40 64.3 74.27 74.05 71.52 56.41 48.44 12 33.93 36.28 33.69 39.53 52.96 74.03 72.75 71.79 56.15 48.51 35.46 13 33.51 37.26 34.08 40.17 51.77 63.75 63.32 74.29 71.46 70.55 56.56 48.09 35.02 14 33.56 36.52 35.57 41.14 52.89 61.99 74.24 71.32 70.38 57.54 47.44 35.49 15 33.58 35.07 36.35 42.57 53.77 62.2 74.86 71.15 69.98 57.99 47.14 35.94 16 35.08 35.24 37.02 45.02 53.37 64.83 70.68 71.64 69.16 56.49 46.75 34.27 17 33.95 34.9 36.47 46.39 54.32 65.14 71.67 71.47 68.91 56.18 45.34 32.34 18 34.25 34.85 35.47 46.13 55.37 66.09 71.82 70.83 68.72 55.08 44.25 32.48 19 33.9 35.01 35.59 45.41 55.2 67.33 71.83 70.81 69.42 55.06 43.83 32.47 20 33.81 36.39 36.37 44.7 54.01 68.73 71.03 71.02 69.10 55.00 42.99 32.48 21 34.23 35.72 37.55 44.61 53.52 69.4 71.27 70.52 68.16 55.31 42.46 32.68 22 34.32 35.08 38.78 44.16 53.11 70.14 71.48 70.62 66.90 54.22 42.17 33.23 23 34.07 35.38 39.75 43.27 53.5 70.15 71.93 69.91 66.82 54.05 41.79 33.65 24 34.53 35.22 40.86 42.53 54.52 70.37 72.02 70.76 66.48 53.82 41.09 33.97 25 35.26 35.03 41.12 42.83 55.82 72.54 72.04 71.02 65.22 52.99 41.45 34.43 26 34.18 34.15 41.27 43.81 56.85 57.87 72.96 71.84 71.54 64.15 55.07 38.32 34.26 27 34.04 33.65 41.23 43.72 73.52 71.75 72.23 63.91 56.90 38.55 34.16 28 33.97 33.42 41.2 44.09 58.66 73.9 71.09 72.60 63.15 54.63 38.03 34.08 29 34.35 32.87 39.64 44.53 59.5 75.05 72.08 73.09 62.60 50.66 38.44 34.32 30 34.91 38.64 46.48 60.05 72.37 73.91 50.19 34.58 31 34.85 37.84 61.12 54.95 66.35 73.42 71.53 69.62 56.83 45.87 35.19 Monthly Avg 34.19 35.27 36.43 42.41 21

2000.

Table 3-4. Hourly Average Temperature of the Vernon Station Fishway during 25-May 26-May 27-May 28-May 29-May 30-May 31-May Day 22-May 23-May 24-May Hour 60.73 52.27 53.85 54.54 55.92 56.81 57.52 58.29 58.6 0

53.64 54.63 55.92 56.8 57.55 58.33 58.61 60.85 1 52.36 53.62 54.69 55.9 56.74 57.63 58.36 58.61 59.98 2 52.26 52.29 53.58 54.77 55.82 56.6 57.6 58.38 58.58 60.39 3

53.53 54.91 55.67 56.46 57.57 58.38 58.51 59.64 4 52.31 53.39 54.9 55.55 56.38 57.56 58.4 58.53 59.31 5 52.34 53.42 54.96 55.57 56.45 57.6 58.47 58.6 59.41 6 52.36 53.39 54.95 55.56 56.58 57.62 58.55 58.72 60.22 7 52.43 52.53 53.47 54.83 55.69 56.74 57.64 58.62 58.93 60.83 8 52.7 53.55 54.9 55.87 56.97 57.71 58.62 59.07 59.81 9 52.71 52.71 52.92 53.63 55.14 56.1 57.13 57.76 58.66 59.16 61.4 10 52.73 53.78 55.26 56.34 57.36 57.92 58.57 59.33 62.84 11 52.72 53.07 53.28 54.07 55.42 56.42 57.41 58.03 58.67 59.44 63.23 12 52.68 53.45 54.09 55.61 56.56 57.36 58.12 58.63 59.59 63.53 13 52.83 53.7 54.18 55.72 56.65 57.42 58.14 58.68 60.17 63.66 14 52.84 53.5 54.42 55.65 56.73 57.49 58628 58.81 62.36 63.61 15 52.79 53.35 54.53 55.67 56.76 57.54 58.29 58.94 62.82 63.71 16 52.78 53.27 54.47 55.65 56.66 57.57 58.32 59.06 62.82 63.54 17 52.68 53.32 54.48 55.63 56.56 57.59 58.31 59.39 62.69 63.81 18 52.61 53.38 54.45 55.69 56.51 57.63 58.29 58.83 62.49 63.88 19 52.57 54.46 55.73 56.51 57.63 58.26 58.76 61.69 63.78 20 52.48 53.43 53.48 54.44 55.74 56.6 57.63 58.27 58.67 60.65 63.13 21 52.38 54.35 55.82 56.71 57.55 58.26 58.61 60.06 62.88 22 52.42 53.45 53.4 54.39 55.88 56.8 57.51 58.32 58.63 60.47 61.64 23 52.41 57.94042 58.63792 60.02083 61.90875 IDaily Avg I52.64563 52.9525 53.96583 55.27875 56.22417 57.13958 22

2000.

Table 3-4. Hourly Average Temperature of the Vernon Station Fishway during 03-Jun 04-Jun 05-Jun 06-Jun 07-Jun 08-Jun 09-Jun 10-Jun Day I 01-Jun 02-Jun

- i Ho~ur 58.58 58.49 60.44 0 65.05 66.16 65.71 66.72 66.13 61.57 62.37 58.59 60.88 1 66.42 65.79 67.31 66.04 61.24 58.44 63.09 65.16 61.26 66.08 67.04 65.69 60.98 58.29 58.62 2 63.32 64.59 66.46 66.9 65.52 60.67 58.21 58.68 61.19 3 63.34 64.82 66.63 66.11 66.08 66.06 65.33 60.47 57.9 58.77 61.06 4 62.96 64.89 66.62 65.77 65.67 65.17 60.2 57.7 58.87 60.94 5 62.41 64.99 66.61 65.63 65.65 65.11 59.88 57.71 59.05 60.69 6 62.16 65.37 66.41 65.93 65.45 64.95 59.52 57.91 59.47 60.98 7 62.37 64.36 65.48 61.7 65.17 66.2 65.44 64.81 59.22 58.04 59.49 8 62.42 64.69 66.55 65.61 64.7 59.03 58.3 59.61 62.62 9 61.96 65.19 65.25 66.84 65.91 64.59 58.77 58.35 59.7 62.97 10 61.19 65.87 65.4 67.28 66.08 64.54 58.61 58.42 60 62.86 11 61.34 64.67 65.58 67.41 65.98 64.28 58.69 58.48 60.98 62.75 12 65.17 65.01 65.86 67.63 65.83 64.29 58.68 59.12 61.14 62.99 13 65.32 65.72 65.96 68.09 66.06 64.15 58.69 58.55 60.3 63.69 14 65.29 66.13 66.32 68.43 66.23 63.87 58.67 58.43 59.66 63.9 15 65.1 65.62 66.68 68.32 66.27 63.69 58.74 58.69 59.54 64 16 64.2 65.72 66.7 67.49 66.47 63.59 58.72 60.02 59.6 63.71 17 64.29 66.06 66.71 67.59 66.51 63.54 58.69 61.15 59.56 63.63 18 64.57 66.45 66.48 67.75 66.48 63.46 58.81 59.16 59.59 63.69 19 65.04 66.06 66.52 67.41 66.44 63.24 58.85 58.49 59.55 64.04 20 65.22 65.86 66.48 67.67 66.5 63.1 58.79 58.53 60.3 64.15 21 65.15 65.93 66.38 67.03 66.47 62.89 58.75 58.47 60.67 64.07 22 65.07 65.28 66.12 66.12 66.66 66.39 62.19 58.73 58.44 60.51 64.15 I 23 64.83 66.03 66.22792 64.36958 59.37375 58.5575 59.61417 62.598331 IDaily Avg 163.67417 65.39667 66.18833 66.89375 23

Table 3-4. Hourly Average Temperature of the Vernon Station Fishwey during 2000.

13-Jun 14-Jun 15-Jun 16-Jun 17-Jun 18-Jun 19-Jun 20-Jun Day 11-Jun 12-Jun Hour 64.08 63.89 63.74 62.24 64.47 66.36 66.3 67.12 0 64.1 64.37 63.07 63.84 63.66 62.09 64.77 66.1 66.36 66.96 1 63.84 64.82 62.98 63.98 63.02 61.93 65.32 65.92 66.32 66.75 2 63.76 64.68 62.72 64.02 62.78 61.32 65.34 65.5 66.19 66.91 3 63.82 64.71 62.7 64 61.75 61.73 65.08 65.44 66.06 66.92 4 63.78 64.79 63.22 64.01 60.6 61.55 65.21 65.47 66.01 66.72 5 63.92 64.43 63.9 64.39 60.48 62.01 65.94 65.61 66.2 66.73 6 64.29 64.65 64.35 64.35 61.77 62.65 66.24 65.55 66.44 67.28 7 64.45 64.51 64.92 64.48 63.53 63.12 66.65 65.35 66.41 67.39 8 64.93 65.13 65.24 64.61 63.59 61.73 67.56 65.37 66.44 67.59 9 65.01 65.24 65.13 64.63 63.63 63.08 67.84 65.51 66.06 67.76 10 65 65.28 65.07 64.28 63.86 64.11 68.21 65.34 66.56 67.89 11 65.1 65.4 65.34 64.47 63.71 64.28 67.82 65.76 66.5 68.29 12 65.07 65.4 65.44 64.59 63.84 64.43 66.16 66.26 66.68 68.51 13 65.33 65.67 65.45 64.58 63.7 64.33 66.09 66.2 67.14 68.86 14 66.22 65.48 65.37 64.63 63.43 64.25 66.86 66.33 67.18 69.22 15 65.83 65.97 65.3 64.77 63.1 64.31 66.7 66.28 67.61 69.56 16 65.69 65.92 65.09 64.63 63.36 64.38 66.42 66.3 67.63 69.89 17 65.58 65.75 65.06 64.57 63.36 64.12 66.54 66.32 67.53 69.64 18 66.33 65.59 65.04 64.18 63.17 64.15 66.2 66.15 67.1 69.74 19 65.46 65.78 64.62 63.94 62.96 64.36 66.22 66.08 67.25 69.26 20 65.06 65.63 64.52 63.77 62.66 64.74 66.56 66.06 67.23 68.91 21 64.63 65.33 64.09 63.7 62.5 64.88 66.77 66.15 67.21 68.81 22 64.66 64.7 63.89 63.63 61.41 64.55 66.52 66.27 67.28 68.55 23 64.71 64.19 64.2475 62.90042 63.3475 66.31208 65.90333 66.73708 68.13583 Daily Avg 64.85708 65.1425 64.44125 24

during 2000.

Table 3-4. Hourly Average Temperature of the Vernon Station Fishway 25-Jun 26-Jun 27-Jun 28-Jun 29-Jun 30-Jun 22-Jun 23-Jun 24-Jun I Day 21-Jun Hour 74.26 74.71 0 69.99 70.49 70.63 71.4 74.11 73.76 73.39 68.52 73.35 74.39 74.77 1 68.47 70.17 70.1 70.45 71.19 74.04 74.05 70.01 71.19 74 74.12 73.33 74.37 74.7 2 68.61 69.74 70.25 69.97 71.01 74.02 74.11 73.43 73.93 74.73 3 68.67 69.64 69.87 70.07 70.89 74.01 73.85 73.41 72.39 74.78 4 68.55 68.65 69.7 70.13 70.98 73.8 73.59 73.24 72.3 74.8 5 68.57 68.16 69.55 70.2 71.12 73.82 73.65 73.54 72.38 74.76 6 68.81 67.78 69.6 70.53 71.01 73.68 74.02 73.89 73.33 74.85 7 68.98 68.63 69.82 69.97 70.73 70.89 73.46 74.32 73.79 74.43 75.21 8 69.52 69.78 70.97 71.01 73.82 74.39 74.1 74.8 75.3 9 70.19 70.57 70 71.19 71.29 73.75 73.81 74.05 75.25 75.4 10 70.22 70.27 70.39 71.91 71.63 73.97 73.67 74.65 75.92 75.73 11 70.07 70.87 70.46 72.22 71.99 73.8 73.63 75.71 76.44 75.9 12 70.49 71.46 70.7 72.26 72.31 74.03 74.08 75.63 76.4 76.01 13 70.42 71.84 70.91 72.32 72.78 74.55 73.81 75.46 76.28 76.15 14 70.58 71.89 71.32 72.46 72.81 75.06 74.01 74.93 76.26 76.13 15 70.57 71.31 71.66 71.86 73.05 72.93 75.18 74.47 74.83 76.35 76.06 16 70.69 71.61 72.89 73.17 74.96 74.79 74.93 75.79 75.89 17 70.63 71.42 71.94 72.38 73.17 74.62 74.28 74.92 75.48 75.62 18 70.4 71.52 71.14 71.78 73.23 74.46 74.03 74.62 75.4 75.34 19 70.1 71.62 71.36 71.53 73.49 74.82 74.04 74.5 75.16 75.59 20 69.81 71.04 71.53 74.77 73.93 74.4 75.06 75.7 21 69.58 71.06 71.32 71.3 74.38 71.29 74.31 74.56 73.7 74.1 74.92 75.61 22 69.34 71.11 71.01 71.26 74.1 74.53 73.58 74.25 74.79 75.5 231 69.19 71.21 70.74 72.17833 74.2425 73.98708 74.26875 74.83667 75.385 DailyAvg 69.62417 70.4725 70.65375 71.31375 25

2000.

Table 3-4. Hourly Average Temperature of the Vernon Station Flshway during 04-Jul 05-Jut 06-Jul 07-Jul 08-Jul 09-Jul 10-Jul Day 01-Jul 02-Jul 03-JuI Hour 75.2 75.56 76.38 76.45 77.14 76.74 76.46 75.63 75.12 0 75.46 75.03 75.78 1 76.15 76.44 76.96 76.72 76.16 75.62 74.95 75.36 75 75.51 76.06 76.29 76.8 76.73 75.95 75.36 74.98 2 75.2 75.31 76.08 76.68 76.6 75.81 75.25 74.79 74.93 3 75.09 75.97 76.59 76.41 75.72 75.23 74.5 74.87 75.21 4 75.02 75.85 75.88 76.48 76.15 75.63 75.21 74.45 74.8 75.15 5 74.96 75.8 75.83 76.09 75.57 75.25 74.35 74.79 75.27 6 74.93 75.59 75.93 76.43 76.34 76.23 75.5 75.24 74.38 74.82 75.47 7 75.09 75.71 75.92 76.47 75.65 75.42 74.48 74.9 75.76 8 75.39 76.05 76.1 76.4 76.57 76.66 75.77 75.67 74.64 75.14 75.96 9 75.8 76.39 76.49 76.75 77.23 76.08 75.87 74.93 75.57 75.81 10 76.24 77.08 77.59 77.21 77.51 76.02 76.33 75.32 76.26 75.84 11 76.56 77.45 78.13 77.53 78.03 76.46 76.56 75.59 76.34 76.25 12 76.99 77.57 78.09 77.98 78.46 76.85 76.63 75.7 76.28 76.4 13 76.61 77.74 77.85 78.77 78.48 76.8 76.66 75.71 75.8 76.18 14 76.44 77.58 77.54 77.73 78.95 78.21 76.74 76.6 75.67 75.53 76.17 15 76.93 77.47 77.62 78.2 78.02 76.78 76.53 75.67 75.43 76.29 16 77.02 77.25 77.95 77.77 76.79 76.39 75.93 75.28 76.33 17 77 77.19 77.33 77.12 78.04 77.58 76.47 76.19 75.86 75.25 76.14 18 76.78 76.99 77.82 77.3 76.35 76.36 75.7 75.24 75.86 19 76.53 77.08 76.98 76.8 77.41 77.05 76.1 75.92 75.57 75.21 75.65 20 76.28 76.83 77 76.84 76.85 75.93 75.52 75.44 75.2 75.45 21 76.4 76.64 76.89 76.7 75.76 75.36 75.32 75.04 75.141 22 76.64 76.59 77.26 77.25 76.75 76.56 75.59 75.26 75.29 75.09 74.99 23 76.47 76.57 76.1225 75.83583 75.18 75.29167 75.72833 DailyAvgj 76.04958 76.66583 76.90417 77.22833 77.10625 26

during 2000.

of the Vernon Station Fishway Table 3-4. Hourly Average Temperature 11 -Jul 12-Jul 13-Jul Day Hour 74.62 74.76 73.84 0

74.55 74.71 73.69 1

74.42 74.62 73.49 2

3 74.29 74.36 73.38 4 74.34 73.69 73.381 74.35 73.12 73.28 5

74.33 72.66 73.17 6

74.7 72.96 73.09 7

75.05 73.65 73.44 8

75.81 74.55 72.2 9

10 75.81 74.77 11 75.49 74.99 12 75.5 75.06 13 75.72 75.54 14 75.81 75.43 15 76.02 75.47 16 76.03 75.6 17 75.84 75.43 18 75.6 75.42 19 75.65 75.22 20 75.65 74.89 21 75.52 74.61 22 75.02 74.21 23 74.85 73.98 73.296 Daily Avg 75.20708 74.57083 27

4.0 MACROINVERTEBRATE COLLECTIONS 4.1 METHODS OF COLLECTION AND PROCESSING 4.1.1 Dredge Collections Benthic macroinvertebrates were collected with a 9-inch ponar dredge in June, August, and October 2000 at Stations 2, 3, 4, and 5 (Figure 4-1). Dredge samples were collected at three locations per Station (near the New Hampshire shore, mid-stream, and near the Vermont shore) and three replicates were collected at each location (for a total of 108 dredges). All dredge samples were sieved through a standard USGS number 30 sieve in the field, prior to being preserved in 70%

ethanol for later identification in the lab.

In the laboratory, the three preserved replicate macroinvertebrate ponar dredge samples for each quarter point per location (NH, mid-stream, and VT), per station (2, 3, 4, and 5) were combined and the contents mixed (for a total of 36 dredge samples). All samples were sorted in entirety under low magnification (2x), and specimens were removed from the combined sample residue. Permit conditions were met with respect to macroinvertebrate dredge sampling.

4.1.2 Macroinvertebrate Rock Basket Collections Rock baskets used in 2000 were made of one-inch square, 14 gauge galvanized wire with PVC coating. The cylindrical basket measured 6.5 inches in diameter and 11 inches in length. Each rock basket was filled with clean rocks from the Connecticut River. Two rock baskets were deployed at Stations 2 Vermont south and 3 Vermont in June and August (Figure 4-1). The Station 2 rock baskets deployed in June were retrieved in July after 50 days of sampling. The rock baskets deployed in June at Station 3 Vermont could not be located upon attempting retrieval in July and were considered lost. Therefore, there is no rock basket data for June at Station 3-Vermont. The Station 2 and 3 rock baskets deployed in August sampled for 42 days prior to retrieval in September.

Although the NPDES Permit states that macroinvertebrate rock basket sampling shall consist of two samples between June and October, this was not strictly followed at the upstream sampling Stations (4 and 5) during 2000. Two rock baskets were deployed at Stations 4 Vermont north and 5 Vermont in May, July, and August (Figure 4-1). Rock baskets prematurely deployed in May (5/9/00) at the upstream Stations were retrieved in June (6t28/00) after sampling for 51 days. Due to the premature deployment of the upstream rock baskets, the baskets were re-deployed in early July (7/6100). This redeployment was done to accomplish sampling during the period that would otherwise have been missed due to the early May deployment coupled with the NPDES permit specified sampling duration of 30-60 days. The July deployed rock baskets were retrieved in August (8/11/00) after 37 days of sampling. The Station 4 and 5 rock baskets were immediately re-deployed in August (8/11/00) and sampled for 42 days prior to retrieval in September (9/21/00).

Upon retrieval, the rock baskets were placed into individual coolers and returned to the lab. The rocks were washed into a number 30 sieve and examined for attached organisms. Rock basket samples were preserved in 70% ethanol for later identification in the lab.

28

In each case, one of the two preserved replicate macroinvertebrate rockbasket samples collected at Stations 2, 3, 4, and 5 was randomly selected and examined in entirety under low magnification (2x)

(for a total of nine rock basket samples examined).

Identification of organisms to the lowest possible taxonomic level, given their life stage and condition, was accomplished using dissecting (45x) and compound (1,00Ox) microscopes.

Chironomnids and oligochaetes were separated by subfamily, tribe, or recognizable type prior to identification to the genus/species level. All or representative subsamples from each grouping were prepared, by clearing and mounting, and identified with a compound microscope. Where subsampled, the number of specimens identified to genus/species was used to proportion the remaining individuals from each group into specific taxa. In instances where chironomid or oligochaete specimens could be identified to genus or species without the aid of a compound microscope, no preparation was necessary. Taxonomic keys used to identify all specimens in addition to chironomids and oligochaetes, were: Burks (1953), Hitchcock (1974), Burch (1975),

McCafferty (1975), Brown (1976), Simpson and Bode (1980), Wiederholm (1983), Klemm (1985),

Roback (1985), Brinkhurst (1986), Peckarsky (1990), Jokinen (1992), Merritt and Cummins (1996),

Wiggins (1996).

4.2

SUMMARY

During 2000, 36 dredge samples and nine rock basket samples were processed. From these samples, 3,820 macroinvertebrates were identified (Table 4-1). Organisms collected by dredge and cage samples made up 64% and 36% of the total, respectively (Tables 4-2 and 4-3a).

Dipterans, oligochaetes, and gastropods accounted for 83% of the invertebraites collected by dredge at the downstream Stations 2 and 3 (Table 4-2). Dipterans, oligochaetes, gastropods, isopods, and amphipods accounted for 87% of the invertebrates collected by dredge at the upstream Stations 4 and 5 (Table 4-2). As in previous years, isopods accounted for 27% of the invertebrates collected by dredge at the upstream Station 5 (Table 4-2). Some of the other taxa collected by dredge upstream of Vernon Dam included ephemeropterans, bivalves, and trichopterans; contributing a combined relative abundance of 8% (Table 4-2). In general, more invertebrates were collected by dredge upstream (1918) of the Vernon Dam, than by dredge downstream (511) of the dam.

The downstream Stations rock baskets were sampled according to the NPDES stipulated sampling schedule. However, because the upstream Stations rock baskets deviated from that stipulated in the Permit, the results of the upstream rock basket collections are presented in two tables. Table 4-3a displays the composition of macroinvertebrates collected by rock basket at all Stations (upstream and downstream) over all sampling dates. Table 4-3b contains data from only the upstream sampling stations, by the three sampling events.

In general, the number of invertebrates collected by rock basket was greater upstream of Vernon Dam (897) than downstream of the Dam (94) (Table 4-3a). Rock basket collections at downstream Stations 2 and 3 resulted in the collection of 42 and 52 organisms, respectively (Table 4-3a). ).

Overall, sixty-seven percent of the organisms collected at Station 2 were dipterans (Table 4-3a).

The organisms collected in the downstream Station 3 rock basket samplers were predominantly amphipods, constituting 8 1%of the total Station 3 catch (Table 4-3a). Over all sampling events, the upstream Stations 4 and 5 rock baskets collected a total of 489 and 408 organisms, respectively (Table 4-3a). Forty-seven percent of the macroinvertebrate composition collected at Station 4 29

consisted of Turbellarian worms (Table 4-3a). The organisms collected in the Station 5 rock baskets across all collections were dominated by decapods (41%), followed by gastropods (20%)

(Table 4-3a).

9 May - 28 June 2000 Rockbasket Collection The rock baskets deployed at the upstream Stations in early May resulted in the collection of similar taxa as was collected by rock basket during the rest of the year. Oligochaetes contributed 30.9% of the relative abundance of all organisms collected at Station 4 (Table 4-3b). Dipterans and amphipods contributed 26% and 23 % to the Station 4 relative abundance, respectively (Table 4-3b).

The Station 5 rock basket was dominated by the collection of decapods (85%) (Table 4-3b).

6 July - 11 August 2000 Rockbasket Collection Amphipods and mayflies (ephemeropterans) contributed equally to the relative abundance at Station 4 (30% each) (Table 4-3b). Other organisms contributing less than 6% to the over all Station 4 abundance during this time period included turbellarian worms, gastropods, isopods, dipterans, and caddisflies (trichopterans) (Table 4-3b).

Over half of the organisms collected at Station 5 during this sampling period consisted of gastropods (57%) with an additional 25% of the collection comprised of amphipods (Table 4-3b).

11 August - 21 September 2000 Rockbasket Collections During this late summer rock basket collection, turbellarian worms constituted 61% of the relative abundance of the Station 4 rock basket sample, and 20% of the Station 5 sample (Table 4-3b).

Amphipods contributed and additional 25% to the total catch at Station 4, while gastropods, trichopterans, and oligochaetes contributed an additional 19% or less to the station 5 abundance (Table 4-3b).

30

Table 4-1. Checklist of Macroinvertebrates Collected from The Connecticut River Near Vernon, Vermont In 2000.

Downstream Upstream Species Station 2 Station 3 StationTotalf 4 Count 5 StationTota Count  % of Count  % Count %of Count  % of Total Total Total Total Hydrozoa Hydra sp. 1 100 Totals 1 100 Platyhelminthes Turbellaria Dugesia tigrina 1 100 233 100 28 100 Totals I 100 233 100 28 100 kematoda 4 100 4 100 Totals 4 100 4 100 Nemertinea Anopla Prostoma graescense 3 100 4 100 Totals 3 100 4 100 Annelida Hirudinea Batracobdella phalera 1 16.7 Gloiobdella elongata 2 33.3 Helobdella fusca 1 16.7 Helobdella sp. 1 25 Helobdella triseralis 1 25 Mooreobdella sp. 2 50 2 33.3 Totals 4 100 6 100 Oligochaeta Arcteonais lomondi 8 5.7 2 1.3 Aulodrilus americanus 1 1.9 3 2 Aulodrilus pluriseta 6 10 3 2.1 4 2.6 Aulodrilus sp. 2 3.3 19 13.5 Branchiura sowerbyi 3 5 2 1.4 11 7.2 Enchytraeidae 1 1.7 1 0.7 3 2 Ilyodrilus templetoni 2 3.8 4 2.6 Limnodrilus sp. 1 1.9 21 35 37 26.2 56 36.6 Lumbricidae 2 3.8 5 8.3 10 7.1 22 14.4 Lumbriculidae 12 20 3 2 Lumbriculus variegatus 2 3.8 23 16.3 7 4.6 Nais simplex 14 9.9 Nais sp. 1 0.7 Piquetiella michiganensis 2 3.8 Ripistes parasita 2 3.3 31

Table 4-1 (Continued).

Downstream Upstream Station 2 Station 3 Station 4 Station 5

% of  % of  % of  % of Count Total Count Total Count o TotalTol Count o Stylaria lacustris 1 1.7 7 4.f Tubificidac imm. w/ capilliform chactae 31 58.5 8 5.7 2 1.2 Tubificidac imm. w/o capilliform chaetae 12 22.6 7 11.7 16 11.3 28 18.2 Totals 53 100 60 100 141 100 153 I(C Polychaeta Manayunkia speciosa 2 100 Totals 2 100 Aollusca Gastropoda Amnicola limosa 9 14.3 93 69.9 177 92.1 Ferrissia rivularis 50 79.4 Ferrissia sp. 1 100 3 4.8 Gyraulus parvus 22 16.5 6 3.1 Gyraulus sp. 7 5.3 2 1 Helisoma trivolvis L 0.5 Menetus dilatatus 1 0.8 Physa sp. 1 1.6 10 7.5 6 3.1 Totals 1 100 63 100 133 100 192 100 Bivalvia Elliptio complanata 2 50 Pisidium sp. 2 50 11 84.6 12 75 69 100 Sphaeriidae 3 18.8 Sphaerium striatinum 1 7.7 1 6.3 Unionidae 1 7.7 Totals 4 100 13 100 16 100 69 100 Arachnida Acarina Hydrachnidia 1 100 1 100 Totals 1 100 1 100 Crustacea Brachiopoda Cladocera 400 100 Totals 400 100 Isopoda Caecidotea sp. 59 100 295 100 Totals 59 100 295 100 Amphipoda Hyalella azteca 1 100 46 100 260 100 109 100 Totals 1 100 46 100 260 1t0 109 100 32

Table 4-1 (Continued).

Downstream Upstream Station 2 Station 3 Station 4 Station 5 SCount  % ount  % of Count %of Count %of Total Total Total Total Decapoda Crangonyx pseudogracilis 4 66.7 15 7.8 Crangonyx sp. 13 6.7 Orconectes sp. 1 100 2 33.3 165 85.5 Totals 1 100 6" 100 193 10c

[nsecta Ephemeroptera Caenis punctata 5 10.6 1 4.31 Caenis sp. 1 14.3 6 12.8 1 4.3 Centroptilum sp. 1 2.1 Hexagenia limbata 16 34 6 26.1 Stenacron sp. 2 28.6 19 40.4 15 65.2 Stenonema sp. 1 33.3 4 57.1 Stenonema terminatum 2 66.7 Totals 3 100 7 100 47 100 23 IOC Odonata Boyeria sp. 1 2V Boyeria vinosa 1 u*

2 52 Enallagma sp. 1 100 6 75 Stylurus sp. 2 25 Totals 1 100 8 100 4 [OC Coleoptera Dineutus sp. I 10 Dubiraphia sp. 1 t00 8 80 24 88.S Optioservus sp. 1 10 1 3.I Oreodytes sp. 1 31I Peltodytes sp. 1 31 Stenelmis sp. 1 100 Totals 1 100 1 100 10 100 27 10(

Megaloptera Sialis sp. 1 100 2 I(K Totals 1 100 2 10(

Trichoptera Ceraclea sp. 2 4 Ceratopsyche sp. 40 80 Cheumatopsyche sp. 1 12.5 3 6 1 2.5 Cyrnellus sp. 1 12.5 Hydroptila sp. 2 5.1 Macronychus glabratus 1 2.5 1 2.6 Macrostemum zebratum 1 2 Molanna sp. 1 2.6 33

Table 4-1 (Continued).

Downstream Upstream Station 2 Station 3 Station 4 Station 5 Sees% of  % of  % of  % of

% of Count %Tota Count o Total Total Total Total Mystacides sp. 2 5 Neureclipsis sp. 3 6 Occetis sp. 14 35 2 5.1 Phylocentropus sp. 16 40 22 56.4 Polycentropodidae 1 2.5 Polycentropus sp. 6 75 5 12.5 10 25.6 Pycnopsyche sp. 1 2.6 Triaenodes sp. 1 2 Totals 8 100 50 100 40 100 39 10O Diptera Ablabesmyia sp. 1 0.6 1 0.8 5 1.2 2 0.7 Acricotopus sp. 3 1 Apedilum sp. 3 1 Chironomini 2 0.5 1 0.3 Chironomus sp. 30 18.1 2 1.7 17 4.1 1 0.3 Chrysops sp. 1 0.8 3 0.7 1 0.3 Cladopelma sp. 1 0.2 Cladotanytarsus sp. 4 3.4 54 13 9 3.1 Clinotanypus sp. 1 0.6 1 0.2 11 3.8 Corynoneura sp. 1 0.2 Cricotopus brevipalpis gr. 1 0.3 Cricotopus sp. 1 0.6 12 4.2 Cricotopus sylvestris gr. 4 I 3 Cryptochironomus fulvus gr. 7 4.2 5 4.2 27 6.5 5 1.7 Cryptotendipes sp. 2 1.7 3 0.7 14 Culicoides sp. 1 0.6 3 Demicryptochironomus sp. 2 0.5 4 IA Dicrotendipes modestus 1 0.2 Dicrotendipes sp. 2 1.2 1 0.8 16 3.8 8 21 Endochironomus nigricans 1 02 Endochironomus sp. 4 I 4 1.4 Eukieferriella sp. 3 1.8 1 0.2 Glyptotendipes sp. 1 0.6 2 0.5 1 0.2 Harnischia gr. 1 0.6 Hemerodromia sp. 1 0.2 Larsia sp. 1 002 Mallachohelea sp. 1 0.6 Microtendipes sp. 1 0.2 Monodiamesa sp. 7 1.7 3 Nanocladius sp. 1 0.2 1 02 Orthocladiinae 1 0.6 5 1.2 34

Table 4-1 (Continued).

Downstream Upstream Station 2 Station 3 Station 4 Station 5 Sees% of %of  % of  % of

% of Count %o out Count o Total Total Total Total Orthocladius sp. 1 0.6 6 5.1 6 1.4 4 ý 1.4 Pagastiella sp. 2 1.2 Palpomyia gr. 2 0.5 2 0.71 Parachironomus arcuatus 1 0.3 Parachironomus sp. 1 0.3 Paracladopelma sp. 1 0.3 Paralauterborniella sp. 1 0.2 Paratanytarsus sp.  ! 0.2 15 5.2 Paratendipes sp. 3 2.5 Phaenopsectra sp. 5 1.7 Polypedilum fallax 1 0.8 Polypedilum halterale gr. 19 11.4 33 7.9 8 2.8 Polypedilum scalaenum gr. 2 1.2 13 11 1 0.2 2 0.7 Polypedilum sp. 5 4.2 11 2.6 9 3.1 Polypedilum tritum 1 0.6 4 3.4 3 0.7 5 1.7 Potthastia longimanus gr. 1 0.2 Procladius sp. 1 0.6 38 9.1 19 6.f Prodiamesa olivacea 1 0.6 Psectrocladius sp. 3 2.5 5 1.2 4 1.4 Pseudochironomus sp. 2 1.7 33 7.9 2 0.7 Rheosmittia sp. 1 0.3 Rheotanytarsus sp. 35 29.7 Sphaeromias sp. 81 48.8 27 22.9 53 12.7 67 23.3 Stempellina sp. 3 0.7 Stenochironomus sp. 1 0.6 1 0.2 2 0.7 Stictochironomus sp. 6 3.6 2 0.1 Tanytarsus sp. 1 0.6 1 0.8 12 2.9 32 11.1 Thienemanniella sp. 8 1.9 Tribelos sp. 2 1.7 45 10.8 14 4.S Totals 166 100 118 100 416 100 288 lOC Grand total (all taxa) 237 100 768 100 1383 100 1432 10C 35

Table 4-2. Composition Of Macroinvertebrates Collected By Ponar Grab In 2000 Downstream And Upstream Of Vernon Dam.

Downstream Upstream Station 2 Station 3 Station 4 Station 5 Count  % of total Count  % of total Count % of total Count  % of total Hydrozoa 1 0.3 ematoda 4 0.4 4 0.4 urbellaria 1 0.3 3 0.3 3 0.3 irudinca 2 0.2 4 0.4 ligochaeta 48 24.6 60 19 109 12.2 135 13.2 olychaeta 2 0.6 Castropoda 1 0.5 60 19 108 12.1 111 10.8 ivalvia 2 1 13 4.1 16 1.8 67 6.5 kcarina 1 0.3 1 0.1 sopoda 49 5.5 282 27.5 kmphipoda 4 1.3 174 19.5 76 7.4

)ecapoda 1 0.3 27 2.6

,phemeroptera 3 1.5 2 0.6 23 2.6 8 0.8 onata 1 0.3 5 0.6 3 0.3 leoptera 1 0.5 1 0.3 5 0.6 21 2.1 Wegaloptera 1 0.1 rrichoptera 2 1 50 15.8 27 3 16 1.6 ptera 138 70.8 116 36.7 365 40.8 266 26 pla 3 0.9 3 0.3 otals 195 100 316 100 894 too 1024 100 36

Table 4-3a. Composition Of Macroinvertebrates Collected By Rock Baskets In 2000 Downstream And Upstream Of Vernon Dam.

Downstream Upstream Station 2 Station 3 Station 4 Station 5 Count % of Total Count % of Total Count % of Total Count % of Total Turbellaria 230 47 25 6.1 Hirudinea 2 0.4 2 0.5 Oligochaeta 5 11.9 32 6.5 18 4.4 Gastropoda 3 0.7 25 5.1 81 19.9 Bivalvia 2 4.8 2 0.5 Isopoda 10 2 13 3.2 Amphipoda 1 2.4 42 9.3 86 17.6 33 8.1 Decapoda 6 1.2 166 40.7 Ephemeroptera 5 1.1 24 4.9 15 3.7 Odonata 3 0.6 1 0.2 Coleoptera 5 1 6 1.5 Megaloptera 1 0.2 1 0.2 Trichoptera 6 14.3 13 2.7 23 5.6 Diptera 28 66.7 2 0.4 51 10.4 22 5.4 Anopla _1 1 0.2 Totals 42 100 52 100 489 100 408 100 37

Table 4-3b. Composition Of Macroinvertebrates Collected By Rock Baskets Set In May, July and August of 2000 At The Upstream Stations Only.

May - June July - August August - September Station 4 Station 5 Station 4 Station S Station 4 Station 5

%of %or %ot %oo %ot Count  % Count Count Count Count Count Total Total Total Total Total Total Turbellaria 2 2.5 2 5.4 226 60.9 25 20.3 Hinudinea 1 1.2 I 0.5 1 2.7 1 1.1 Oligochacta 25 30.9 1 2.7 6 1.6 18 14.6 Gastropoda 3 3.7 4 2.1 2 5.4 53 57.0 20 5.4 24 19.5 Bivalvia 2 1.6 lsopoda 4 4.9 2 1.0 2 5.4 4 4.3 4 1.1 7 5.7 Amphipoda 19 23.5 5 2.6 11 29.7 23 24.7 56 15.1 5 4.1 Decapoda I 1.2 163 84.9 I 2.7 2 2.2 4 1.1 I 0.8 Ephemeroptera 1 1.2 1 0.5 1I 29.7 4 4.3 12 3.2 10 8.1 Odonata i 1.1 3 0.8 Coleoptera 2 2.5 1 0.5 1 2.7 I 1.1 2 0.5 4 3.3 Megaloptera I 2.7 1 0.8 Trichoptera 2 2.5 3 1.6 2 5.4 I 1.1 9 2.4 19 15.4 Diptera 21 25.9 12 6.3 2 5.4 3 3.2 28 7.5 7 5.7 Anopla I I I _I_1 1 0.3 Totals 81 100.0 192 100.0 37 100.0 93 100.0 371 100.0 123 100.0 38

0 1 2l1 0 I1iI Mile N

I Vemnax Dam Figure 4-1. NPDES Macroinvertebrate dredge and rock basket sampling stations 2,3,4, and 5.

39

5.0 FISH COLLECTIONS During the annual Environmental Advisory Committee meeting on 18 April 2000, the trapnet portion of the current NPDES permit was removed from the sampling program due to concerns raised by the participating State agencies over the potential impact trap netting could pose to a new nesting pair of bald eagles. Fluctuating river flows regularly resulted in the partial exposure of the trapnets above the water surface during the four 48-hour sampling periods in May, June, September, and October. The agencies' concern centered on the possible entanglement of an eagle in a partially exposed trapnet full of fish. Therefore, unlike previous year's reports no trapnet data is reported herein.

The electrofishing samples were collected at the Stations specified in the NPDES permit and outlined in Figure 5-1. Larval fish were collected weekly from 2 May through 11 July 2000 in the vicinity of the Vermont Yankee intakes, and fish impinged on the circulating water traveling screens were collected weekly from I April through 15 June, and again from 28 July through 26 October.

Electrofishing specifically for anadromous fish was conducted twice a month in July through October, at the specified Stations.

5.1 METHODS OF COLLECTION AND PROCESSING 5.1.1 Electrofishine - General Sampling Electrofishing was conducted utilizing a boat-mounted Coffelt Electronics Model VVP-15 electroshocker. Monthly sampling was conducted during May, June, September, and October in the evening beginning approximately 0.5 h after sunset at the following Stations: Rum point, Station 5, Station 4, NH Setback, 0.1 mi. below Vernon Dam, Station 3, Stebbin Island, and Station 2 (Fig. 3-1). All fish collected were identified to species, weighed to the nearest gram (wet weight), and measured to the nearest millimeter (total length). NPDES permit conditions were met with respect to the general fisheries electrofishing program.

5.1.2 Electrofishing - Anadromous Fish Juvenile American shad electrofishing collections were conducted twice a month during July through October at Stations 0.1 mi. south of Vernon Dam, Station 3, and Stebbins Island (Figure 5-1). Non-target fish (non-clupeids) were not collected during the juvenile American shad electrofishing runs. Collected juvenile shad were weighed (to the nearest gram wet weight) and measured (mm total length). All anadromous fish electrofishing samples were successfully collected as outlined in the NPDES permit.

5.1.3 Impingement Weekly and 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> spring and fall impingement samples were collected on each Monday and Tuesday, respectively, between 1 April and 15 June, and 28 July through 26 October 2000. Weekly samples (i.e., Monday collections) consisted of back-washing the traveling screens into the collection bin. The debris was then examined for Atlantic salmon and American shad. The screens were again back-washed approximately 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> later (i.e., Tuesday collections) and all fish were removed, identified to species, weighed (to the nearest gram wet weight), and measured (mm total 40

length). The Atlantic salmon and American shad impingement limits of 301 salmon and 5,083 shad were not exceeded during 2000. Permit compliance was met with respect to impingement sampling.

5.1.4 Larval Fish Larval fish samples were collected weekly from 2 May through 11 July in the vicinity of the Vermont Yankee intake structure (Fig. 3-1). A 50-cm diameter, 363-Arm nitex nylon plankton net was towed along side the boat, at surface (approx. 0.3 m), mid (approx. 1.8 m), and near bottom (approx. 3.7 m) depths. A flume-calibrated, General Oceanics Inc. Model 2030R mechanical flowmeter was mounted in the net mouth and used to estimate the volume of each tow.

The contents of the retrieved plankton nets were washed into a collection cup on the end of the net.

Larval fish samples were preserved in 5% formalin for laboratory sorting and identification.

Ichthyoplankton was separated from debris using an 8x to 80x variable magnification dissecting microscope. Larval fish were identified to the lowest feasible taxonomic level utilizing the following published larval keys: Fish (1930), Lippson and Moran (1974), Jones et al. (1978), and Auer (1982). All larval fish samples were collected in compliance with the NPDES permit requirements.

5.1.5 Scale Samples for Age Determination Scale samples, used for age determination, were removed from yellow perch, largemouth bass, smallmouth bass, and walleye collected by electrofishing. No white perch were collected via electrofishing; therefore, no scale samples were collected for this species. Scale samples taken from the four species were removed from an area ventral to the lateral line at the tip of the depressed pectoral fin. All fish were released back to the river near the point of capture.

5.2

SUMMARY

Twenty-six species of fish were collected during 2000 (Table 5-1). This total number is similar to recent years (Aquatec 1993, 1995, and Normandeau Associates 1997, 1998, and 1999). All collected species were typical of the Connecticut River drainage; no federally listed threatened or endangered species were collected.

S.2.1 Fish - NPDES General Electrofishina, and Impingement During 2000, a total of 40 electrofishing collections were completed at the ten locations within the eight NPDES permit designated Stations (Fig. 5-1). The total number of fish collected by electrofishing was 980 (Table 5-2). The average catch per unit effort (CPUE) for the 40-electrofishing collections was 153.1. The total electrofishing effort was 6.4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />.

41

There were 1,938 fish collected in 2000 during impingement and general electrofishing (Table 5-3).

Numerically, the most abundant species were yellow perch (30.8%), Bluegill (26.5%), rock bass (8.8%), pumpkinseed (5.4%), and spottail shiner (5.2%). Yellow perch (18.9%), bluegill (17.1%),

smallmouth bass (11.3%), and largemouth bass (11.0%) accounted for the majority of the biomass of collected fishes (Table 5-3).

Upstream of Vernon Dam, yellow perch, bluegill, and rock bass, accounted for 71.5% of all fish collected (Table 5-4). Seven American shad were collected upstream of Vernon Dam from the circulating water traveling screens at the Plant Intake structure and one was collected by electrofishing. American shad contributed 0.5% to the total upstream catch. Other fish contributed 5.5% (pumpkinseed) or less to the total relative abundance. Yellow perch (22.3%), bluegill (17.9%), largemouth bass (13.2%), and white sucker (11.3%) accounted for the majority of the biomass of the fish collected at the upstream Stations (Table 5-4).

Downstream of Vernon Dam, spottail shiner, smallmouth bass, fallfish, bluegill, and rock bass accounted'for 77.0% of the total catch (Table 5-5). Twelve American shad were collected downstream of Vernon Dam during the general electrofishing collections (i.e., not including anadromous species electrofishing collections conducted specifically for American shad).

Smallmouth bass (47.8%), bluegill (13.2%), and fall fish(7.8%), contributed the greatest biomass to the downstream collections.

Seven American shad were collected on the traveling screens in October (Table 5-6). Nine Atlantic salmon were collected on the traveling screens, one the last day of March, five in April, and three in May 2000. The American shad and Atlantic salmon impingement limits of 5,083 shad and 346 salmon were not exceeded during 2000. The June, August, and September impingement samples consisted of a total of 20, 14, and 15 fish collected, respectively. Pumpkinseed and rock bass were numerically the most abundant species in the impingement samples during those three months.

Up to 20 scale samples collected from the electrofishing sampling programs were analyzed for age determination of smallmouth bass, largemouth bass, yellow perch, and walleye (Tables 5-8, 5-9,5-10, and 5-11).

5.2.2 Anadromous Fish Electrofishine In fulfillment of the NPDES permit requirements for anadromous fish sampling, electrofishing samples were collected twice a month during July through October 2000 at Stebbins Island, Station 3, and 0.1 mile below Vernon Dam (Fig. 3-1). Results reported in this section include American shad collected during the anadromous fish collections only and not those shad reported above in the general electrofishing section.

A total of 57 American shad was collected via electrofishing between July and 2 November (the last scheduled October 2000 anadromous fish electrofishing trip was postponed until 2 November due to a shortage of qualified personnel in late October), (Table 5-12). August yielded the highest catch of shad (31) compared to the other three months. Shad lengths recorded in August ranged from 54 - 83 mm total length and weight ranged from 1 - 4 g (Table 5-12). The twice-monthly collections during July, September, and October resulted in the collection of 1,20, and 5 American shad, respectively.

The American shad collected in July measured 41 mm total length. The American shad collected during September ranged in length from 78 - 106 mm. October shad collections produced a catch 42

ranging in length from 101 - 110 mm. The CPUE in August was highest at Station 3 (24) followed by Stebbins Island (16.5) (Table 5-12). The CPUE in September was highest at Stebbins Island (12.8) and the CPLUE in October was highest at Station 3 (12). No shad were collected on 2 November 2000 (Table 5-12).

5.2.3 Ichthvoplankton Thirty-three ichthyoplankton samples were collected near the Vermont Yankee intakes between 2 May and 11 July 2000 (Table 5-13). A total of 490 ichthyoplankters were identified (Table 5-14).

Irrespective of the volume sampled, of the ichthyoplankton captured, spottail shiner represented 39.8% of the ichthyoplankton captured, followed by white perch (28.8%), yellow perch (14.7) and white sucker (14.5%). Other species collected included walleye, pumpkinseed, common carp and Clupeidae. Table 5-15 provides a breakdown of extrapolated ichthyoplankton estimates presented as density (no./100 cubic meters). Most fish were collected at the 0.3 meters depth; with respect to time, most fish were collected in May and the first two weeks of July 43

Table 5-1. Checklist of Fishes (AFS 1991) Collected During 2000.

CHORDATA AGNATHA PETROMYZONTIFORMES Petromyzontidae Petromyzon marinus Sea lamprey OSTEICHTHYES ANGUILLIFORMES Anquillidae Anguilla rostrata American eel SILURIFORMES Ictaluridae Ameiurus sp. Ameiurus sp.

Ameiurus natalis Yellow bullhead Ameiurus nebulosus Brown bullhead SALMONIFORMES Salmonidae Salmo salar Atlantic salmon Esocidae Esox lucius Northern pike Esox niger Chain pickerel Diaphanusfundulus Banded killifish CYPRINIFORMES Cyprinldae Catostomidae Catostomus commersoni White sucker Cyprinidae Cyprinidae Cyprinus carpio Common carp Hybognathus regalis Eastern silvery minnow Notemigonus crysoleucas Golden shiner Notropis hudsonius Spottail shiner Notropis sp. Notropis sp.

Semotilus corporalis Fallfish CLUPEIFORMES Clupeldae Alosa sapidissima American shad Dorosoma cepedianum Gizzard shad PERCIFORMES Percldae Yellow perch Percaflavescens Stizostedion vitreum Walleye Percicthyldae Morone americana White perch Centrarchidae Ambloplites rupestris Rock bass Lepomis gibbosus Pumpkinseed Lepomis macrochirus Bluegill Micropterusdolomieu Smallmouth bass Micropterussalmoides Largemouth bass Pomoxis nigromaculatus Black crappie Etheostoma olmstedi Tesselated darter 44

Table 5-2. Catch per unit of effort (CPUE) for electrofishing collections in the Connecticut River in the vicinity of Vernon Vermont for Section I of the NPDES Permit in 2000.

Electrofishing Stations Number of Hours Fish CPUE Collections Station 3 - Vermont 4 0.7 61 91.5 Station 5 - New Hampshire 4 0.5 89 178.0 Station 5 - Vermont 4 0.7 101 151.5 New Hampshire Setback 4 0.7 190 285.0 Rum Point 4 0.7 125 187.5 Station 2 - New Hampshire 4 0.7 27 41.5 Station 4 - New Hampshire 4 0.7 161 241.5 Station 4 - Vermont 4 0.7 113 165.4 Stebbin Island - New Hampshire Side 4 0.7 81 121.5 0.1 Miles south of Vernon Dam 4 0.6 32 56.5 TOTAL 40 6.4 980 153.1 45

Table 5-3. Number and weights of fishes collected in the Connecticut River upstream and downstream of Vernon Dam In 2000 (electrofishing and impingement samples).

Relative Total Relative Species Total (#) Number (%) Weight (g) Weight (%)

Sea lamprey 13 0.7 29 0.04 American eel 2 0.1 455 0.56 American shad 20 1.0 158 0.20 Gizzard shad 2 0.1 840 1.04 Atlantic salmon 9 0.5 238 0.29 Northern pike 4 0.2 3510 4.34 Chain pickerel 15 0.8 2130 2.63 Banded killifish 1 0.1 1 0.00 Cyprinidae 1 0.1 1 0.00 Common carp 3 0.2 1568 1.94 Eastern silvery minnow 11 0.6 51 0.06 Golden shiner 39 2.0 568 0.70 Spottail shiner 101 5.2 216 0.27 Notropis sp. 11 0.6 40 0.05 Fallfish 26 1.3 1019 1.26 White sucker 18 0.9 8250 10.20 Ameiurus sp. 1 0.1 1 0.00 Yellow bullhead 7 0.4 1187 1.47 Brown bullhead 16 0.8 1385 1.71 White perch 28 1.4 230 0.28 Rock bass 171 8.8 5522 6.82 Pumpkinseed 105 5.4 4075 5.04 Bluegill 513 26.5 13836 17.10 Smallmouth bass 62 3.2 9099 11.25 Largemouth bass 67 3.5 8925 11.03 Black crappie 83 4.3 803 0.99 Tesselated darter 2 0.1 3 0.00 Yellow perch 596 30.8 15252 18.85 Walleve 11 0.6 1520 1.88 TOTAL 1938 100.0 80912 100.00 46

Table 5-4. Numbers and weights of fishes captured upstream of Vernon Dam in 2000 in impingement and general electrolishing.

Electrofishing CWTS Summary Species Total Total Relative Relative Number Weight Number Weight Total (#) Number Total (g) Weight (g) (0) M M Sea lamprey 1 12 29 13 0.7 29 0.

American shad 1 7 7 66 8 0.5 73 0.1 Gizzard shad 1 40 1 0.1 40 0.1 Atlantic salmon 9 238 9 0.5 238 0.4 Northern pike 4 3510 4 0.2 3510 5.2 Chain pickerel 12 1974 2 16 14 0.8 1990 2.9 Banded killifish 1 1 1 0.1 1 0.0 Common carp 2 1568 2 0.1 1568 2.3 E.silvery minnow 5 28 6 23 11 0.6 51 0.1 Golden shiner 24 284 12 82 36 2.1 366 0.5 Spottail shiner 50 111 50 2.9 111 0.2 Notropis sp. 10 39 10 0.6 39 0.1 White sucker 11 7654 1 14 12 0.7 7668 11.3 Ameiurus sp. 1 1 1 0.1 1 0.0 Yellow bullhead 7 1187 7 0.4 1187 1.7 Brown bullhead 3 1145 13 240 16 0.9 1385 2.0 White perch 28 230 28 1.6 230 0.3 Rock bass 24 1667 134 3216 158 9.1 4883 7.2 Pumpkinseed 70 3170 25 646 95 5.5 3816 5.6 Bluegill 221 8205 269 3908 490 28.2 12113 17.9 Smallmouth bass 10 2201 10 653 20 1.2 2854 4.2 Largemouth bass 47 8848 20 77 67 3.9 8925 13.2 Black crappie 12 533 71 270 83 4.8 803 1.2 Tesselated darter 2 3 2 0.1 3 0.0 Yellow perch 272 11572 322 3569 594 34.2 15141 22.3 Walleye 2 352 3 465 5 0.3 817 1.2 Total 779 54017 958 13825 1737 100.0 67842 100.0 47

Table 5-5. Numbers and weights of fishes captured downstream of Vernon Dam in 2000 in general electrofishing (i.e. non-anadromous fish specific electrotishing runs).

Electrofishing Summary Species Number Total Relative Relative Weight (g) Total (#) Number (%) Weight(%)

American eel 2 455 2 1.0 455 3.5 American shad 12 85 12 6.0 85 0.7 Gizzard shad 1 800 1 0.5 800 6.1 Chain pickerel 1 140 1 0.5 140 1.1 Cyprinidae 1 1 1 0.5 1 0.0 Common carp 1 1 0.5 Golden shiner 3 202 3 1.5 202 1.5 Spottail shiner 51 105 51 25.4 105 0.8 Notropis sp. 1 1 1 0.5 1 0.0 Fallfish 26 1019 26 12.9 1019 7.8 White sucker 6 582 6 3.0 582 4.5 Rock bass 13 639 13 6.5 639 4.9 Pumpkinseed 10 259 10 5.0 259 2.0 Bluegill 23 1723 23 11.4 1723 13.2 Smallmouth bass 42 6245 42 20.9 6245 47.8 Yellow perch 2 111 2 1.0 111 0.8 Walleye 6 703 6 3.0 703 5.4 Total 201 13070 201 100.0 13070 100.0 48

Table 5-6. Monthly impingement of fish on Vermont Yankee's circulating water travelling screens in 2000.

Specie. March April May June August September October No. Wt. No. Wt. No. Wt. No. Wt. No. Wt. No. Wt. No. Wt.

Atlantic salmon 1 23 5 160 3 55 E. silvery minnow 2 10 4 13 Golden shiner 3 25 8 47 1 10 Rock bass 30 279 62 1853 10 17 5 67 5 88 22 912 Pumpkinseed 3 18 12 504 10 124 Bluegill 48 572 131 1605 2 3 3 350 7 1200 78 178 Smallmouth bass 1 5 3 149 3 131 1 300 1 35 1 33 Black crappie 2 12 4 15 65 243 Yellow perch 93 1154 219 2328 5 11 2 14 3 62 Walleye 1 250 1 130 1 85 Sea lamprey 11 25 1 4 Notropis sp. 10 39 White sucker 1 14 Brown bullhead 9 65 4 175 White perch 1 90 27 140 Ameiurus sp. I I Tesselated darter 2 3 American shad 7 66 Gizzard shad 1 40 Chain pickerel 2 16 Largemouth bass 20 77 Total 1 23 188 2485 479 6932 20 162 14 746 15 1326 241 2151 Note: weight Is in grams.

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Table 5-7. Age-specific length and weight statistics for random subsample of white perch collected in 2000.

No adult white perch were collected in 2000.

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Table 5-8. Age-specific length and weight statistics for random subsample of smallmouth bass collected in 2000.

Number of Total Length (mm) Total Weight (g)

Fish Avg. SD MIN MAX Avg. SD MIN MAX Annuli 2 6 154 17 136 185 43 15 30 69 3 12 176 31 141 250 70 45 35 185 4 4 215 51 160 280 126 97 45 265 5 3 333 73 250 389 508 300 200 800 7 5 418 42 350 464 984 247 610 1300 51

Table 5-9. Age-specific length and weight statistics for random subsample of largemouth bass collected In 2000.

Number of Total Length (mm) Total Weight (g)

Fish Avg. SD MIN MAX Avg. SD MIN MAX Annuli 3 1 239 239 239 165 165 165 4 3 272 14 259 286 377 280 210 700 5 4 256 29 230 289 240 74 140 315 6 5 319 39 288 379 422 169 295 690 7 2 406 49 371 440 990 438 680 1300 8 1 491 491 491 1400 1400 1400 52

Table 5-10. Age-specific length and weight statistics for random subsample of yellow perch collected in 2000.

Number of Total Length (mm) Total Weight (g)

Fish Avg. SD MIN MAX Avg. SD MIN MAX Annuli 3 6 162 18 141 187 49 20 25 79 4 8 177 16 152 195 62 17 31 79 5 17 213 28 170 259 106 41 39 170 6 4 220 33 171 241 117 45 51 145 7 4 232 33 205 280 145 73 95 250 53

Table 5-11. Age-specific length and weight statistics for random subsample of walleye collected in 2000.

Number of Total Length (mam) Total Weight (g)

Fish Avg. SD MIN MAX Avg. SD MIN MAX Annuli 2 1 227 227 227 87 87 87 14 1 4 1275 48 221 326 172 75 87 265 54

Table 5-12. Summary of 2000 Anadromous Fish Collections (American shad) at Stebbins Island, Station 3, and 0.1 Mile Below Vernon Dam.

No.of CMinimum Maximum Minimum Maximum Month and Station Fish Hours Uatch per Length Length Weight Weight Unit Effort (mm) (mm) (g) (g)

July Station 3 0 0.32 0.0 - - -

Stebbin Island 1 1.22 0.8 41 41 -

0.1 Miles south of Vernon Dam 0 0.32 0.0 - - -

August Station 3 8 0.33 24.0 56 70 2 3 Stebbin Island 22 1.33 16.5 54 83 1 4 0.1 Miles south of Vernon Dam 1 0.33 3.0 65 65 3 3 September Station 3 3 0.33 9.0 78 94 1 5 Stebbin Island 17 1.33 12.8 88 106 2 9 0.1 Miles south of Vernon Dam 0 0.33 0.0 -. -

October Station 3 2 0.17 12.0 101 102 8 8 Stebbin Island 3 0.67 4.5 101 110 8 10

0. 1 Miles south of Vernon Dam 0 0.17 0.0 - - -

November Station 3 0 0.17 0.0 - -

Stebbin Island 0 0.63 0.0 - -

0.1 Miles south of Vernon Dam 0 0.17 0.0 - -

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Table 5-13. Vermont Yankee Ichthyoplankton Sampling Effort In 2000.

May June July Total Depth (m) 0.3 5 4 2 11 1.8 5 4 2 11 3.7 5 4 2 11 Totals 15 12 6 33 56

Table 5-14. Collection Dates And Total Number Of Ichthyoplankton Collected Near The Vermont Yankee Intake In 2000.

Volume Species Earliest Latest Sampled Number Percent Capture Capture (Cubic Meters)

Clupeidae 06JunOO 06JunOO 286.17 1 0.2 Common carp 28JunO0 28JunOO 509.78 2 0.4 Spottail shiner 29MayOO 1 IJulOO 2242.15 195 39.8 White sucker 29MayOO 13JunOO 870.56 71 14.5 White perch 22MayOO 06Jul00 2235.98 141 28.8 Pumpkinseed 22MayOO I lJul00 2503.42 6 1.2 Yellow perch 02MayOO 29MayOO 1552.56 72 14.7 Walleye 15MayOO 22MayOO 564.63 2 0.4 490 100.0

• Volume sampled is sum of volumes between earliest and latest capture date 57

Table 5-15. Ichthyoplankton Density per 100 Cubic Meters at the Vermont Yankee Intakes By Depth in 2000.

Date and Taxon DEPTH (m) TOTALS 0.3 1.8 3.7 02May00 Yellow perch 0.76 1.80 2.56 09MayOO Yellow perch 50.66 14.21 64.86 15MayOO Walleye 1.07 1.07 Yellow perch 3.09 1.07 4.15 22MayOO Pumpkinseed 0.89 0.89 Walleye 2.03 2.03 White perch 0.89 1.00 2.03 3.93 Yellow perch 1.79 2.99 4.78 29MayOO Spottail shiner 0.85 0.85 White perch 25.52 29.60 55.13 White sucker 44.03 44.03 Yellow perch 0.85 0.85 06JunOO Clupeidae 1.13 1.13 Spottail shiner 0.87 0.87 White perch 10.21 19.38 29.59 White sucker 15.59 15.59 13JunO0 White perch 1.10 1.23 2.33 White sucker 1.10 1.10 22JunOO Spottail shiner 4.27 0.96 5.23 White perch 10.61 5.77 16.38 28JunOO Common carp 0.64 0.64 Spottail shiner 4.45 1.17 0.32 5.94 White perch 1.78 10.49 7.38 19.65 06JulOO Pumpkinseed 0.98 2.99 3.98 Spottail shiner 22.48 0.98 2.00 25.46 White perch 6.98 6.98 1 IJulO0 Pumpkinseed 0.83 0.83 Spottail shiner 116.54 12.08 5.56 134.18 Totals 218.30 132.64 104.07 455.01 58

6.0 2000 ZEBRA MUSSEL AND ASIATIC CLAM MONITORING 6.1 METHODS OF COLLECTION AND PROCESSING Larval (veliger) sampling was conducted bi-weekly between 15 June and 17 October 2000.

Collections were made at quarter points (NH and VT shores, and mid-river) at Vermont Yankee stations 4 and 5 (Fig 3). Approximately 1,000 liters of river water was pumped through 64-micron plankton net at each quarter point. Six samples were collected during each bi-weekly collection trip for a total of 66 veliger samples. Samples were preserved in 70% ethanol for examination in the lab.

Juvenile/adult (settling stage) zebra mussel sampling was conducted between 22 May and 3 November 2000 near the New Hampshire and Vermont shores at Vermont Yankee stations 4 and 5 (Fig 3). Two settlement plate samplers were deployed at each station for a total of eight samplers.

Settlement plates were made of six, 6 in X 6 in plates of PVC strung onto a bolt with approximately 0.5 in between plates. The sampler was suspended in the water column at 2-3 m below the surface, depending on river depth at the sampling station. The plate sampler at each Station was examined approximately every two weeks with a hand-held magnifying lens for newly settled zebra mussels.

One plate from each sampler was then randomly selected and cleaned into a number 64-micron sieve. The sample was then preserved in 70% ethanol for examination in the lab.

One plate sampler deployed at Station 4 Vermont on 11 July 2000, could not be located two weeks later when retrieval was attempted. A new plate sampler was deployed at that location on the day the plate sampler was determined to be gone and was checked approximately 2 weeks later for settlement. Therefore, one zebra mussel settling plate sample was not collected between 11 July and 11 August 2000.

Asiatic clam samples were collected with a 9 inch ponar dredge in June, August, and October 2000 at Stations 2, 3, 4, and 5 (Figure 6-1). Dredge samples were collected at three locations per Station (near the New Hampshire shore, mid-stream, and near the Vermont shore) and three replicates were collected at each location (for a total of 108 dredges). All dredge samples were sieved through a standard USGS number 30 sieve in the field, prior to being preserved in 70% ethanol for later identification in the lab.

6.1.1 Laboratory Identification Procedures Zebra mussel veliger samples were emptied into a petri dish and examined in entirety with cross-polarized light on a dissecting microscope with 40x magnification. The use of cross polarized light allows zebra mussel veligers to be distinguished from other planktonic organisms that are also collected in the samples, as the larval shells stand out as bright spots against a dark background (Johnson 1996).

In the laboratory, the three preserved replicate corbicula ponar dredge samples for each quarter point per location (NH, mid-stream, and VT), per station (2, 3, 4, and 5) were combined and the contents mixed (for a total of 36 dredge samples), then examined in entirety under low magnification (2x).

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6.2

SUMMARY

River water temperatures ranged from 1.5' to 26.60 C, dissolved oxygen ranged from 7.4 to 10.4 mg/l, and pH ranged from 6.2 to 8.2 during veliger and settlement plate sampling in the vicinity of the Vermont Yankee Plant (Stations 4 and 5). Water temperature ranged between 11.2 to 240 C, dissolved oxygen ranged from 6.4 to 9.0 mg/l, and pH ranged from 6.6 to 8.0 during dredge collections of Asiatic clams in June, August, and October.

There were no Asiatic clams or any life stages of zebra mussels found in any samples collected during the 2000 Vermont Yankee monitoring program.

In addition to the zebra mussel sample collections, 13 zebra mussel awareness programs were presented during 2000 to a variety groups in Massachusetts, New Hampshire and Vermont, including local high schools, rotary clubs, lake homeowners associations, environmental education centers, and the Fairbanks museum.

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7.0 LITERATURE CITED AFS (American Fisheries Society) 1991. Common and scientific names of fishes: Special Publication 20.

Bethesda, Maryland.

Aquatec. 1993. Ecological studies of the Connecticut River, Vernon, Vermont. Report 22, January December 1992. Report prepared for Vermont Yankee Nuclear Power Corp., Brattleboro, VT.

Aquatec. 1995. Ecological studies of the Connecticut River, Vernon, Vermont. Report 24, January December 1994. Report prepared for Vermont Yankee Nuclear Power Corp., Brattleboro, VT.

Auer, N.A. (ed.). 1982. Identification of larval fishes of the Great Lakes basin with emphasis on the Lake Michigan drainage. Great Lakes Fishery Commission, Ann Arbor, MI. Special Publication. 744 pp.

Binkered, R.C. 1978. 316 Demonstration, Engineering, Hydrological & Biological Information and Environmental Impact Assessment. Aquatec, Inc. for Vermont Yankee Nuclear Power Corporation.

Brinkhurst, R.O. 1986. Guide to the freshwater aquatic microdrile oligochaetes of North America. Department of Fisheries and Oceans. Canadian Special Publication of Fisheries and Aquatic Sciences Vol. 84. Ottawa, Canada.

Brown, H.P. 1976. Aquatic dryopoid beetles (Coleoptera) of the United States. U.S. Environmental Protection Agency, Office of Research and Development. Water Pollution Control Research Series 18050 EID04/72.

Cincinnati, OH.

Burch, J.B. 1975. Freshwater unionacean clams (Mollusks: Pelecypoda) of North America. Revised edition.

Malacological Publications. Hamburg, Michigan.

Burks, B.D. 1953. The mayflies of Ephemeroptera of Illinois. Bull. Ill. Nat. Hist. Survey 26(1).

Downey, P.C. and R.C. Binkered. 1990. 316 Demonstration, Engineering, Hydrological & Biological Information and Environmental Impact Assessment. Aquatec, Inc. for Vermont Yankee Nuclear Power Corporation.

Fish, M.P. 1930. Contributions to the early life histories of sixty-two species of fishes from Lake Erie and its tributary waters. U.S. Bur. Fish. Bull. 47(10): 293-398.

Hitchcock, S.W. 1974. Guide to the insects of Connecticut, part VII. The Plecoptera, or stoneflies of Connecticut. State Geological and Natural History Survey of Connecticut. Department of Environmental Protection. Bulletin Number 107. Hartford, CT.

Johnson, L.E. 1996. Enhanced early detection and enumeration of zebra mussel (Dreissena spp.) veligers using cross-polarized light microscopy. Hydrobiologia. 312(2). pp. 139.

Jokinen, E.H. 1992. The freshwater snails (Mollusks: Gastropoda) of New York State. New York State Museum Bulletin 482.

Jones, P.W., F.D. Martin, and J.D. Hardy, Jr. 1978. Development of fishes of the mid-Atlantic bight. An atlas of egg, larval, and juvenile stages. Volume I. Acipenseridae through Ictaluridae. U.S. Fish and Wildlife Service. FWSIOBS - 78/12.

Klemm, DJ. led.). 1985. A Guide to the freshwater Annelida (Polychaeta, Naidid, and Tubificid Oligochaeta, and Hirudinea) of North America. Kendall/ Hunt Publishing Company. Dubuque, Iowa.

Lippson, AJ., and R.L. Moran. 1974. Manual for identification of early developmental stages of fishes of the Potomac River estuary. Power plant-siting proj. MD Dept. Nat. Res. 282 pp.

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McCafferty, W.P. 1975. The burrowing mayflies (Ephemeroptera: Ephemeroidea) of the United States.

Transactions of the American Entomological Society, Vol. 101: 447-504.

Merritt, R.W., and K.W. Cummins. (eds.). 1997. An introduction to the aquatic insects of North America (third edition). Kendall/Hunt Publishing Company. Dubuque, Iowa.

Normandeau Associates, Inc. 1997. Ecological studies of the Connecticut River Vernon, Vermont. Report 26, January - December 1996.

Normandeau Associates, Inc. 1998. Ecological studies of the Connecticut River Vernon, Vermont. Report 27, January - December 1997.

Normandeau Associates, Inc. 1999. Ecological studies of the Connecticut River Vernon, Vermont. Report 28, January - December 1998.

Normandeau Associates, Inc. 2000. Ecological studies of the Connecticut River Vernon, Vermont. Report 29, January - December 1999.

Normandeau Associates, Inc. 2000a. Composition of Adult American Shad at the Vernon Hydroelectric Dam Fishway During Spring 1999. Vermont Yankee/Connecticut River System Analytical Bulletin 72. Prepared for Vermont Yankee Nuclear Power Corporation, Brattleboro, VT.

Normandeau Associates, Inc. 2000b. Abundance ofjuvenile American shad in the Vernon pool during 1999.

Vermont Yankee/Connecticut River System Analytical Bulletin 73. Prepared for Vermont Yankee Nuclear Power Corporation, Brattleboro, VT.

Normandeau Associates, Inc. 2001. Abundance of juvenile American shad in the Vernon pool during 2000.

Vermont Yankee/Connecticut River System Analytical Bulletin 74. Prepared for Vermont Yankee Nuclear Power Corporation, Brattleboro, VT.

Peckarsky, B.L. 1990. Freshwater macroinvertebrates of northeastern North America. Cornell University Press.

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Roback, S.S. 1985. The immature chironomids of the eastern United States VI. Pentaneurini Genus Ablobesmyfa. Proceedings of the Academy of Natural Sciences of Philadelphia, PA. 137(2):

153-212.

Simpson, K.W., and R.W. Bode. 1980. Common larvae of Chironomidae (Diptera) from New York state streams and rivers, with particular reference to the fauna of artificial substrates. New York State Museum Bulletin No. 439. Albany, NY.

Wiederholm, T. led.). 1983. Chironomidae of the holarctic region, Keys and diagnoses. Supplement No. 19.

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