ML18283B697
ML18283B697 | |
Person / Time | |
---|---|
Site: | Browns Ferry ![]() |
Issue date: | 06/30/1975 |
From: | Tennessee Valley Authority |
To: | Office of Nuclear Reactor Regulation |
References | |
RH-75-2-BF1 | |
Download: ML18283B697 (42) | |
Text
RH-75-2-BF1 ENVIRONMENTAL RADIOACTIVITY LEVELS BROWNS FERRY NUCLEAR PLANT July-December 1974 JUNE 1975
CONTENTS Introduction Figure 1-Tennessee Valley Region Table 1-Environmental Radioactivity Sampling Schedule Figure 2-Atmospheric and Terrestrial Monitoring Network 2 5 Atmospheric Monitoring 7 Table 2 Table 3 Table 4 Table 5 Table 6-Radioactivity in Air-Maximum Permissible Concentrations Nonoccupational Exposure-R ain~~~~~~~~~~~~~~-Total Fallout Deposited-Charcoal Filters.for~~~~~~~~9 ll 12 14 15 Terrestrial Monitoring 17 Figure 3 Table 7 Table 8 Table 9 Table 10 Table ll Table 12 Table 13-Milk Monitoring Network Milk o~~~~~~~~~~-Vegetation
.-S oil~~~~~~~~~~~-Private Well Water-Public Water.-Environmental Gamma Radiation-Poultry and Food Crops~~~~Levels~~~~~~~18 20 21 23 24 25 26 27 Reservoir Monitoring 29 Table 14-Figure 4-Table 15-Table 16-Table 17-Table 18-Table 19-Table 20-Table 21-Sampling Schedule-Reservoir Reservoir Monitoring Network River Water, Dissolved Activi River Water, Total Activity River Water Fish~~~~~~~~~~~Plankton Sediment C 1am~~~~~~~~~~~Monitoring ty.~~~~31 32 33 34 35 36 37 38 39 Quality Control Data Analysis Conclusions 41 41~~~~~~~~~~~~~~~~~~~~~~~~~~41 ENVIRONMENTAL RADIOACTIVITY LEVELS BROWNS FERRY NUCLEAR PLANT JULY-DECEMBER 1974 Introduction The Browns Ferry Nuclear Plant (BFNP), operated by the Tennessee Valley Authority, is located on a site owned by TVA containing 840 acres of land in Limestone County, Alabama, bounded on the west and south by Wheeler Reservoir (see figure 1).The site is 10 miles southwest of Athens, Alabama, and 10 miles north-west of Decatur, Alabama.The plant, when completed, will consist of three boiling water reactors;each unit is rated at 3,293 MWt and 1,098 MWe.Unit 1 achieved criticality on August 17, 1973, and began commercial operation on August 1, 1974.Unit 2 began commercial operation on March 1, 1975.The preoperational environmental monitoring program established a baseline of data on the distribution of natural and manmade radioactivity in the environment near the plant site.However, seasonal, yearly, and random variations in the data were observed.In order to determine the potential increases in environmental radioactivity levels caused by the plant, comparisons were made between data for indicator stations (those near the plant)and control stations (those remote from the plant).Field staffs in the Division of Environmental Planning and the Division of Forestry, Fisheries,, and Wildlife Development carried out the sampling program outlined in tables 1 and 14.Sampling locations are shown in figures 2 and 4.All the radiochemical and instrumental analyses were conducted in a central laboratory at Muscle Shoals, Alabama.Alpha and beta analyses were performed on Beckman Low Beta II and Beckman Wide Beta II low background proportional counters.Two Nuclear Data Model 2200 multichannel analyzer systems were used to analyze the samples for specific gamma-emitting radionuclides.
Data were coded and punched on IBM cards or automatically printed on paper tape for computer processing specific to the analysis conducted.
An IBM 370 Model 165 computer, employing an Alpha-M least squares code, was used to solve multimatrix problems associated with estimating the activities of the gamma-emitting nuclides.A primary difficulty in sample analysis was the detection of very low radionuclide concentrations.
The minimum sensitivities are those concentrations where the percent" unting error is 100%, calculated assuming a 3-sigma counting error, when standard sample sizes and counting time are employed.The minimum sensitivities are therefore those concentration values below which it is impossible to state, at the 99 percent confidence level, that any amount of radioactivity above background exists in the sample.The sensitivities, based wholly on counting statistics, are listed for gross alpha, gross beta, and tritium analyses.
MEMPHIS//\I I L L.').("-+'~/PAOICAH (M 0..5'(/+p'ACKSON+
(LOUISVILLE N D..t-.-~TENNESSEE VALlEY REGION 4 (TVA NUCLEAR PLANT SITES)V A BOWUNG GREEN S MVSCLE SHOALS , VOVIENSSORO K E N T U C K Y (V~7 I'.J~.f C\R I/v~g/1 L.r NASHVILL C OAK RIGGERS N N E\M//(~r l r (~HP)JI I P~J CHATTANOOGA'~/
I r'C A R lg/M I SS./(~-)~~A L A B A M A G EORG I A LEGEND~-HARTSVILLE NUCLEAR PLANT'~fggP-PHIPPS BEND NUCLEAR PLANP" QFBF-LIQUID METAL FAST BREEDER REACTOR~-WATTS BAR NUCLEAR PLANT ZHf-SEQUOYAH NUCLEAR PLANT]Big-BELLEFONTE NUCLEAR PLANT]KHAN-BROWNS FERRY NUCLEAR PLANT,.~-YELLOW CREEK NUCLEAR PLANT~~>PrOPOSed 3 Standard sensitivities are not listed for specific gamma-emitting radionuclides determined by the Alpha-M program because they are not available.
Since the minimum sensitivities are not defined, some concentrations reported may not represent actual concentrations'.
They may be mathematical artifacts of the Alpha-M program.Concentra-tions with errors (estimated by the Alpha-M program)larger than the reported concentrations are listed as"not detectable" (ND).The errors reported define the statistical distributions of the errors estimated by the Alpha-M least squares program.
Table 1 ENVIROHMEHTAL RADIOACTIVITY SA%'LIHG SCHEDULE Air Charcoal Rain-Heavy Particle River Well Public Aquatic Life dtoti i*riot tiitt trit t t 11 t d ii~vt*rioo Hilk tt t r t r t t r otd d d~ot Muscle Shoals'W W M M M M Lavrenceburg W W M M Q Payet tevtl le W W M M Q Cullman W W M M Q Rogersville
'W W M M Athens Decatur Courtland Site h4-1 W'W M M W W M M W W M M Q W W M M Q Q Site H-2 WW M M Q Site HE-3 W W M M Site HW-4~Farm B Farm Bi Para H Para T Farm L Perm G (Control)Wheeler Dam Elk River Wheelet Reservoir W W M M M W M W M W M'W M M W M Champion Paper Co.W-Weekly M-Monthly Q-Quarterly Figure 2 ATMOSPHERIC AND TERRESTRIAL MONITORING NETWORK RM.2BF LAWRENCEBURG yPULASKI FAYETTEVILLE 0'M-3BF WILSON FLORENCE PM-IBF WHEELER ROGERSVII.I DAM ATHENS PM-2BF FFIEL MUSCLE SHOALS RM-I BF LEIGHTON TUSCUMBIA COURTLAND PM-4 F NUCLEAR PL NT DECAT R PM-3BFO IO MILES BROWNS FERRY HUNTSVILLE pRUSSELLVILLE IL GUNT SV HARTSELLE DAM 25M S HALEYVILLE
'M-5BF CULLMAN 45 MILES 4 RAINWATER SOIL VEGETATION 0-ENVIRONMENTAL MOMTORING STATION NOTE: THE FOLLOWING SAMPLES ARE COLLECTED FROM EACH STATION: AIR PARTICULATES RADIOIODINE HEAVY PARTICLE FALLOUT ATMOSPHERIC MONITORING The atmospheric monitoring network is divided into three groups.Three local air monitors are located on the plant site in the quadrants of greatest wind frequency.
One additional station is located at the point of maximum predicted offsite concentration of radionuclides.
Four perimeter air monitors are located at distances out to 10 miles from the plant, and four remote air monitors are located at distances out to 45 miles.These monitoring stations are shown in figure 2.The remote monitors are used as control or base-line sta'tions.
At, each monitor, air is continuously pulled through a Hollingsworth and Voss HV-70 particulate filter at a regulated flow of 3 ft/min.In series with, but downstream of, the particulate filter is a charcoal filter used to collect iodine.Each monitor has a collection tray and storage container to obtain rainwater on a continuous basis and a horizontal platform that is covered with gummed acetate to catch and hold heavy particle fallout.Thermo-luminescent dosimeters are used to record gamma radiation levels at each remote and perimeter station.Each of the local and perimeter air monitors is fitted with a GM tube that continuously scans the particulate filter.The disintegration rate of the atmospheric radioactivity is continuously recorded at each station and radiotelemetered into the plant.These stations will detect any significant airborne release from BFNP.Air filters are collected weekly and analyzed for gross beta activity.No analyses are performed until 3 days after sample collec-tion.The monthly results are combined for each station to obtain a semiannual average.The average semiannual concentrations for the stations in each group of monitors (Local, Perimeter, and Remote)are combined to yield a semiannual average for each group.These data are presented in table 2.With'reference to table 3, which.contains the maximum permissible concentrations (MPC)recommended by 10 CFR 20 for nonoc-cupational exposure, it is seen that the maximum beta concentration is 0.20 percent MPC.Rainwater is collected and analyzed for gross beta activity, specific gamma-emitting isotopes, and radiostrontium.
For the gross analysis, a maximum of 500 ml of the sample is boiled to dryness and counted.A gamma scan is.performed on a 3.5-liter monthly sample and the results averaged by group location as was done with the air filter data.The strontium isotopes are separated chemically and counted in a low background system.The results are shown in table 4.The highest value reported for beta activity is 1.12 percent MPC for drinking water.,
The gummed acetate that is used to collect heavy particle fallout is changed monthly.The sample is ashed and counted for gross beta activity.The results are given in.table 5.Charcoal filters are collected and analyzed for radioiodine.
The filter is counted in a single channel analyzer system.The data are shown in table 6, where the highest value reported is 0.06 percent MPC for I.
Table 2 RADIOACTIVITY IN AIR Location Local No.of~Sam lee~Cflmeter Nonvolatile Beta*~.Specific Radionuclides in Composite Samples (Avera e Northwest LM-4BF North Northwest 27 27 27 27 0.160 0.168 0.168 0.160 Avera e: 0.026 0.028 0.029 0.021 0.076 0.076 0.076 0.067 0.074 141 144Ce 51C 131I 103 106R 134C 137C"Zr-"5Nb SOC 65z 60C 140B 140"Sr 89S.026+.002.003+.0014.001+.001.009+.002 ND,.002+.0004.010+.001.001+.0003.0045+.0009.0010+.0005 ND.015+.001.001.003 Perimeter Rogersville, AL 27 Athens, AL 27 Decatur, AL 27 Courtland,-
AL 27 0.155 0.023 0.156 0.027 Avera e: '.169 0.029 0.150 0.028 0.069 0.072 0.074 0.069 0.072 141 144 51 Ce 135'103 106 RU 134C 137C 9 5zr-9 5Nb 5 8(.54Nn 65z Co 1 0Ba 1 0La 90S 89S.019-+.005+-.001-+.012-+ND.002+.009+.001+ND ND.PPl+.Oll+.001.002.001.003.0001.002.0003.0005.0005.0003.001*Sensitivity 0.004 ND-Not detectable 10 Location Table 2 (Continued)
No.of Nonvolatile Beta*Sam les Max.Min.Ave.Specific Radionuclides in Composite Samples (Avera e)Remote Muscle Shoals, AL Lawrenceburg, TN Fayetteville, TN Cu'llman, AL 27 27 27 27 0.146 0.171 0.196 0.180 Avera e: 0.028 0.030 0.037 0.032 0.061 0.071 0.078 0.072 0.071'4'44C 51Cr 131I 103 106Ru 134C 13VC 95Z 95Nb 50Co Zn 60C 140Ba140La"Sr 09S.017+.001.002+.002.001+.0001.017+.001 ND.002+.0003 010+.001 ND ND ND ND.011+.001'D.002*Sensitivity 0.004 ND-Not detectable Table 3 MAXIMUM PERMISSIBLE CONCENTRATIONS FOR NONOCCUPATIONAL EXPOSURE Alpha Nonvolatile beta Tritium l 97C 10 3~l06R l 44C"Zr-"Nb l OB l OLa l 3 lZ In Water~Ci/1 30 3,000 3,000,000 20,000 10>000 10,000 60,000 200000 300 In Air pCi/a 100 200,000 500 200 200 1,000 1,000 100" Zn"Mn 6 0(.o 89S"Sr 5 l(r l34C seC 100,000 1000000 30,000 3,000 300 2,000,000',000 90,000 2%000 1's 000 300 300 30 80,000 400 2,000 12 Table 4 RAIN Location yCi/liter No.of Nonvolatile Beta*~Sam les Max.Mie.~Av Specific Radionuclides Avera e Local Northwest LM-4BF North Northeast 7.32 9.30 10.26 8.47 Avera e: 2.74 1.51 3.22 2.47 4.76 5.92 7.26 4.77 5.68 141 144Ce 51Cr 131I i03 106Ru 134CS 137CS 95Zr-"Nb 58(o'4Mn 65Zn Co 140Ba 140La 90Sr"Sr 1.3+0.6 2.2+1.2 0.5+0.2 ND 0.5+0.2 0.6+0.3 0.5+0.2 0.3+0.2 ND 1.3+0.5 4.3+0.4 4.6+0,.4 0.3+0.1 1.9+0.1 Perimeter Rogersville, AL Athens, AL Decatur, AL Courtland, AL 7.82 2.06 13.70 2.38 Avera el 26.71 2.98 7.56 2.78 9.75 4.27 5.04 5.71'.19 141 144Ce<<t 51Cr 131I 103 106R 1 34CS 137(,"'Zr-"Nb bOCo Zn'0(o 140Ba 1 0La"'Sr 89Sr 0.9+0.6 ND 0.3+0.2 0.5+0.5 0.2+0.1 0.7+0.2 0.2+0.2 0.2+0.1 0.8+0.3 0.3+0.3 3.3+0.5 4.7+0.5 0.4+0.1 2.2+0.5*Sensitivity 1.6 ND-Not detectable 13 Table 4 (Continued)
Location No.of Nonvolatile Beta*~Sam lea Max.Min.~Av Specific Radionuclides Avera e)Remote Muscle Shoals, AL Lawrenceburg, TN Fayetteville, TN Cullman,'L 6 33.45 6 30.43 12.14 10.66 Avera e: 2.78 2.70 4.93 3.66 10.02 10.57 8.01 7.99 9.15 44C 51Cr 131Z 103 106Ru 1340 137CS Zr-Nb Co'4Mn Zn"Co 140Ba 140La 90S 89Sr 1.3+0.7 ND 0.3+0.2 1.2+0.7 0.4+0.2 0.9+0.3-1.6+0.4 0.1+0.1 0.6+0.4 0.7+0.4 2.8+0.3 3.8+0.5 0.7+O.l 2.4+0.1 Sensitivity 1.6 ND-Not detectable 14 Table 5 TOTAL FALLOUT DEPOSITED alCi/kilometer Location No.of.Nonvolatile Beta*~Sam lea Max.Mla.~Av Local Northwest LM-4BF North Northeast 0.57 0.49 0.75 0.59 0.19 0.40 0.18 0.43 0.14 0.33 0.20 0.46 Avera e: 0.41 Perimeter Rogersville, AL Athens, AL Decatur, AL Courtland, AL 0.62 0.17 0.39 0.84 0.22 0.48 0.72 0.16 0.43 0.58 0.17 0.37 Avera e: 0.42 Remote Muscle Shoals, AL.Lawrenceburg, TN Fayetteville, TN Cullman, AL 0.80 0.59 0.55 0.70 Avera e: 0.22 0.49 0.20 0.38 0.12 0.31 0.17 0.42 0.40*Sensitivity 0.01 Table 6 CHARCOAL FILTERS I Location No.of Radioiodine*
~Sam lea Moxa Mla.~Av Local Northvest LM-4BF North Northeast 27 27 27 27 0.023 0.022 0.038 0.062 ND Avera e: Perimeter Rogersville, AL Athens, AL Decatur, AL Courtland, AL 27 27 27 27 0.046 ND 0.046 ND 0.042 ND ND*ND Avera e: Remote Muscle Shoals, AL Lavrenceburg TN Fayetteville, TN Cullman, AL 27 27 27 27 0.026 ND 0.039 ND 0.037 ND 0.045 ND Avera e:*Sensitivity 0.022 ND-Not,detectable Terrestrial Monitorin Milk Milk is collected from five farms within a 10-mile radius of the plant, and from one farm approximately 20 miles from the plant (see figure 3).Samples are also purchased from nearby retail distrib-utors.Raw milk is analyzed weekly for I, and all samples are analyzed monthly for gamma-emitting isotopes and for radiostrontium.
The average results for each farm are shown in table 7.So that any relationship between fallout on pastureland and the presence of radionuclides in milk might be seen, pasturage is also sampled at the six farms.A cow census was completed in December 1974.It was determined that there are no dairy farms nearer the plant than the nearest farm being sampled.Ve etation In addition to the pasturage samples mentioned previously, vegetation samples are collected near each monitoring station in the network to determine possible plant uptake of radioactive materials from the soil or from foliar deposition.
Table 8 gives the results obtained from the laboratory analyses..
The data for the specific radionuclide analysis of vegetation are averaged for the four principal locations-local, perimeter, remote-control, and farm.Soil Soil samples are collected near each monitoring station in order that any relationship between the amount of radioactive material found in vegetation and that in soil might be established.
The averages for specific analyses are obtained in the same fashion as those for vegetation.
The results are given in table 9.Water Domestic water supplies, obtained from surface streams and wells, are sampled and analyzed.Well water is obtained from seven private supplies within a 10-mile radius of the plant and from a number of wells on the plant site.The results of analyses of well water are shown in table 10'nd indicate that the maximum beta concen-tration is 0.85 percent MPC.Table ll indicates the results of samples taken from public water supplies.-
The maximum beta concentration is 0.32 percent MPC.The'specific isotopic concentrations reported are averages for each station for the semiannual period.Environmental Gamma Radiation Levels Thermoluminescent dosimeters (TLD's)are placed at nine stations around-the plant near the plant boundary and at the perimeter and remote air monitors to determine the gamma exposure rates at these, locations.
The TLD's are changed every 3 months.The quarterly gamma radiation levels determined from these TLD's are given in table 12.
18 Figure 3 MILK tNNITORINC NETWORK Alhons Clement School 2 EL 5" goo>o noo Rl pl ay 2~Raid 4 le nnes ssee sp,~+o og t srtto.Forts t<<tne 3 Jones Crossroads
$toob im ru el.1.Farm B 2~Farm 3.Farm L 4.Farm T~5~Farm Bi 6.Farm C (approximately 20 miles west of the plant)ALA 20 Scale: 1" 1.5 mite n 19 Poultr and Food Cro s Poultry and food cropsraised in the vicinity of Browns Ferry Nuclear Plant are sampled as they become av'ailable during the*growing season.During this sampling period samples of corn,.peaches, tomatoes,, and wheat wer'e collected and analyzed for gross beta, specific gamma-emitting radionuclides, Sr, and Sr.The results are given in table 13.
'able 7 pCi/liter Location Pasteurized Milk*Athens, AL Decatur, AL Muscle Shoals, AL 6.3-ND 3.2 1 9 0.6 3.4 ND.0.8 Avera e: 1.5 No.of 131Z 2.7 3.1 0.6 2.1 1261.5 1279.5 1291.3 1277.4" 140Ba 140L 1.4 2.2 1.6 5.3 1.6 4.8 1.4 4.5 1.2 4.9 1.4 90S 89'~Raw Milk"~Farm G (Control)Farm B Farm Bi Farm H=Farm L]6 (4)'A**27 (6)22 (5)0.8 , 27 (6)1.4 27 (6)ND 2.4 2.7 4.3 4.7 3.2 1241.8" 1238.6 1281.7 1315.5'300.1 2.3 1.8 0.2 0.4 2.0 9.0 7.8 5.6 4.2 6.8 1.6 0;7 1.8'0.7 1.4 Farm T 27 (6)0.6 4.2 1302.6 0.8 5.3 0.8 Avera e: (Farms B Bi H L T)ND'.8 1287.7 1.0 5.9*I analyzed by gamma scan.+*Chemical separation of iodine:".Sensitivity for Z-.0.5 pCi/1 at time of sample collection.
- Z analysis weekly: (gamma scan and Sr," Sr analyses monthly.)ND-Not detectable 21 Table 8 i VEGETATION'i/
Dr Hei ht Location No.of~Sam les~A1 ha*Nonvolatile Beta**Specific Radionuclides Avera e Local Northwest LM-4BF North Northeast 2 Avera e: ND 14.0 14.7 6.8 12.9 12.1 141 144Ce"Cr 131Z 103 106Ru 1 34(.137Cs 5Zr-s5Nb Co'4Mn"Zn'0Co 140Ba 140La"Sr'SSr 0.6+0.2 0.4+0.1 0.1+0.02 1.2 i 0.1 ND 0.04+0.02 0.9+0.4 0.04+0.03 ND ND ND 0.3+0.03.0.4+0.01 O.l+0.01 Perimeter Rogersville, AL Athens, AL Decatur, AL Courtland, AL Avera e: ND 10.5 10.5 13.5 15.8 12.6 141 144Ce'1(.131I 103 106R 134Cs 137C s5Zr-"5Nb 58Co 54Mn Zn 60(o 140Ba 140L"Sr 8SS 1.2+0.1 0.3+0.1 O.l+0.01 1.5+0.1 ND O.l+0.03 1.4+0.1 0.1+0.03 ND 0.03+0.02 ND 0.3+0.03 0.3+0.01 0.2+0.01*Sensitivity 0.1**Sensitivity O.l ND-Not detectable 22 Table 8 (Continued)
Location No.of~Sam laa'~A1 ha*Nonvolatile Beta**Specific Radionuclides Avera e Remote and Control Muscle Shoals, AL Lawrenceburg, TN Fayetteville, TN Cullman, AL Farm G Avera e: ND 15.1 14.3 13.4 15.6 15.6 14.8 141 144Ce 51(r 131Z 103 106Ru 134CS 137(s"zr-95Nb 58Co'4Mn 6'zn 60C 40Ba 140La 90Sr 89S>>1.2+0.1 0.1+0.03 ND 0.5+0.1 0.02 i 0.01 ND 1.2+0.1 0.1+0.02 ND ND ND 0.3+'0,03 0.7+0.02 O.l+10.02 Nonvolatile Beta Farms Max.Min.~Av.Farm Bi Farm B Farm H Farm L Farm T 27.4 16.5 5.0.18.8 5.0 11.4.23.2 12.9 18.9'.6 28.2 9.2 17.5 Avera e: 15.2 22.0 3.6 141 144Ce 51C 131T 103 106R 134CS 137C"Zr-9'Nb 58C'4Mn zn 60C(-140B 140L"Sr 89S 0.7+0.1 0.3+0.1 ND 0.6+0.1 ND 0.2+0.01 0.7+0.02 ND ND ND~ND p.3+0.01 0.9+0.02 p.3+0.02*Sensitivity 0.1**Sensitivity O.l ND-Not detectable NA-Not analyzed 23 Table 9 SOIL Ci/Dr Wei ht Location No.of~Sam les Nonvolatile Beta*Specific Radionuclides Avera e Local Northwest PM-4BF North Northeast'2 5.84 5.63 4.88 4.40 Ayers e: 5.19 141 144C 51Cr 131I'03 106R 1 34CS 137C 9 5 Zr-9 5 Nb 58C'4Mn 6 Zn 60Co 140 B 1401 0.4+ND ND 0.4+ND 0.7+0.3+ND 0.1+ND ND 0.1+0.2 0.1 0.1 0.1 0.03 0.03 Perimeter Rogersville, AL Athens, AL Decatur, AL Courtland, AL Avera e 4.85 4.83 3.63 2.15 3.87'4'44C 51Cr 131I 103 106RU 134CS 137CS"Zr-95Nb Co 54Mn 6 5Zn 6 0 Co 140Ba 140 0.4+ND ND 0.3+ND 1.1+O.l+ND O.l+ND ND O.l+0.1 0.1 0.1 0.03 0.03 0.02 Remote Muscle Shoals, AL Lawrenceburg, TN Fayetteville, TN Cullman, AL 3.94 4.50 3.56 2.84 Ayers e:'.71 141 144C 51Cr 131I 103 106R 134(137Cs 9 5Z 95Nb Co'4Mn.6hZ 60 Co 140~140 Ba-La 0.5+ND ND 0.4+ND 1.3+O.l+.ND 0.1+ND ND O.l+0.1 0.1 0.05 0.03 0.03 0.02*Sensitivity 0.15 ND-Not detectable
~4 TaDLC 10 PRIVATE NELL MATER 4CClll Loca t ton fern 0 Control No.of SanElcs Nonvolat tlc Serac 2.3 ND S etfle Radlonoclldas 2.0 0.8 0.7t0.6~4 Tn ND 3.8t0.9 4~4 Sa 3~Stl.0 fern 8 tarn SL tarn 8 Fern L 8.3 ND 2.4 7.1, ND 3.2 3.5 2.0 2.6 23.0 ND$.0 6-3.8 L.SAL.6 1.2-0.9 ND 1.6tO.S l.l+0.7 0.8%.5 l.lt0.3 0.4t0.3 0.8r0.6 1 Lt0~5 0.8tO.S 0.8t0.6 2't0~9 1.5t0.6 1.3t0.9 1.5t1.4 5 6r0.8 0.9t0.7$.7~.7.5.3+0 6 6.0t0.9 S.OA0.9 4.8-'0.6 2.9t0.6 3.9 0.7 2.0 0.6 2.8 1.1 Resldcnce RT Residence RI RFNP 1 SfNP-2 StNP-3 RFNP 4 SFIrp s RFNP-6 RFNP-7 CScnsitlvltt 1.6 ND-Not detectable 6.7 ND 6 25.S-ND 4.8 3.4 ND ND 2.7 2~LAL.3 21.7 XD 4.0 Ayers et 1 8 0.340.1 14.7 ND 3.2 1.7t1.3 3.7'D 1.9, ND 1.210.6 0.it 0.2 0.5t0.2 1.8-'0.7 1.L~0.$1.7tl.3 O.L0.2 0.3 0.1 0.440.2 2.ltl.i 2.2t0.9 O.it0.3 L.2t0.4 0.%0.3 0.7t0.4 ND 2.40.7 1-9t0.7 0.3t0.2 0.9 0.4 0.8 0,4 0.8<.5 0.9'O-l 0.9'0.1 0.3~I L.Ot0,4 0.6t0.5 0.7t0.6 ND 0.6t0.1 6.LtL.2 4.6.1.5 S.Li0.7 4.L0.6 5M~0,7.4.0 0.$4.5t0.7 3.IR0.7 2.6 L.l 4~2 0.$4.6tl.2 3.0:0.4 1.90.6 3.0n7.4 050$2.8AL9 5.0%.9 12'07 12ALL 40'OS 3~4tO~9 0.Fn7.4 3.7%.6 0.2N).I 0.5&.2 4.9n).2-.L.st0 2 4'4 locat foo Table 11 yUELIC MATER tCI/tl No.of Moevolatfle Seta*S elf fc Radfoottclfdes tet II.Itt~'I Ro Cs Cs Zr-Mb Co.Mn Zo Co Ea-La Hvs nlioa D Colbart SF Cleseata Scbool Atheas Courtland Tovo Creek Trfafty Decater Sbeffleld Mheeler Dao Chasploe taper Co.2 2.2 1.6 1.9 MD ND 2 2.0 1.4" 1.7 MD ND 2 3.1 0.9 2.0 MD ND 1 3.6 3.6 3.6ÃD ND 2 1.8 1.7 1.8 ND ND 1.5+1.1 2 3.4 1.4 2.4 ND ND 2.1~9 1.5 1.7 MD ND 3.1ZLS 6 2.8 1.1 1.8 l MD ND 6 4.2 0.8 2.1 1.1t0.9ÃD 6 9.6 ND 2.9 ND MD 6 2.7 1.2 1.8 ND ND 6.8t3.7 LZt0.4 1~9 1.0 1.9Z1.4 1.0+1.0 2'+1.6 0.9'.4 ND 0.5t0.4 0.6t0.3 ND 0.6t0.4 0.4t0.4 0.8+0.3 ND" 3.6t3.3 8.9t2.1 6.9+1.7 3.6+0.6 1.5t0.4 1.1+0.4 1.0-1.0 4.2t0.6 4.4t0.4 ND 0 9+0 5 MD 2.0tO.S 2.lt0.6 4.5-0.7 1.7Z0.6 8.2t1.3 4.0t0.9 MD 1.9t1.5 2.7R2.6 5.2+1~4 4~9+1~1 ND 2.5+2~5 7.4+1.3 4.ltl.0 6.7Z1.9 4.4tl.S 5.6t1.9 5.7-1~7 5.0+1.4 6.1t1.3 417.0-63.$
ND'Seealtlvlty 1.6<<Sensitfvity 400 ND-Not detectable Avera e: 2.2 O.ltO.OS MD 0.4r0.2 0.6t0.3 0.8+0.2 0.2t0.1 O.lt0.0$O.lt0.03 0.4t0.1 0.9+0.$$.$t0.4 4.2t0.3~M ls 26 Table 12 ENVIRONMENTAL GAMMA RADIATION LEVELS Quarter July-September, 1974-Location On-Site (9)*Maximum Minimum Average**0.016 0.009 0.014+0.004 35;4 19.9 30.3+10.4 Environmental Gamma Radiation Levels mR Hour~l Off-Site (8)Maximum Minimum Average 0.016 0.008 0.012+0.004 34.1 18.2 25.6+10.4 October-December, 1974 On-Site (9)Maximum Minimum Average Off-Site (8)Maximum Minimum Average 0.013 0.011 0.012+0.002 0.018 0.009 0.012+0.006 29.3 23.2 27;1+3.6 38.8 19.1 27.4+12.8 5Number of stations (three TLD's.at each station)**All averages reported+2a 27 Corn Table 13 POULTRY AND FOOD CROPS Ci/K (wet wei ht Peaches Tomatoes pCi/g Wheat Gross Beta*964.3 787.3 1006.4 1.76 Specific Ra)iynuclides 144C 51C 131I 103t106Ru 134~Cs 137 Cs Zr-Nb 58(4Mn ND ND 3.8+3.1 5.1+3.3 7.0+2.8 ND 3~5+3'2 0.1-0.07 ND 0.03 0.02 0.03+0.02 Zn 60(o 40K140 140L Ba-La 90S 89S ND 2238.8+78.6 2.%1.9 2.08 4.0+3.0 1777.0i78.5 5.>1.9 2.34 4.68 8.0+3.8 1925.8+90.6 6.2+2.7 1.91 2.86 2.8&0.42 0.07+0.02 0.15 0.01*Sensitivity O.l (pCi/g, dry weight)ND-Not detectable 29 Reservoir Monitorin Samples are collected quarterly along seven cross sections in Wheeler Reservoir-at Tennessee River miles 277.98, 283.'94, 288.78, 291.76, 293.70, 295.87, and 307.52 as detailed in table 14.Samples collected for radiological analysis include plankton from three of these cross sections and bottom fauna and sediment from four cross'sections.
The locations of these cross sections are shown on the accompanying map (figure 4)and conform to sediment ranges established and surveyed by the Hydraulic Data Branch, TVA.Station 307.52 is located 13.5 miles upstream from the'plant diffuser outfall and was selected as a control station.Samples of water, net plankton, sediment, Asiatic clams, and two species of fish collected quarterly (plankton in only two quarters)are analyzed for radioactivity.
Gamma and gross'eta activity are determined in water (dissolved and total activity), net.plankton, sediment, shells and flesh of clams, flesh of a commercial and a game fish species and also in the whole body of the commercial species.The~Sr and Sr contents are determined in all samples where sufficient quantities are available.
The activity of 12 gamma-emitting radionuclides is determined with a multichannel gamma spectrometer.
The Sr and Sr contents are determined by appropriate radiochemical techniques.
Water From five of the seven cross sections a total of 15 water samples are collected quarterly for determination of total and dis-solved radioactivity.
The locations and depths for sampling are shown in table 14.Results are displayed in tables 15 and 16.Samples from all horizontal locations and depths at each river mile cross section are compositedquarterly for tritium analysis.Water samples are also collected monthly at the point of plant discharge to the Tennessee-River and at a point on the Elk River.These samples are a part of the quality control program.From the data in table 17, the maximum average beta concentration is 0.69 percent of MPC for samples collected at these two locations.
Fish , Radiological monitoring for fish is accomplished by analysis of composite samples of adult fish taken from each of three contiguous reservoirs
-Wilson, Wheeler,,and Guntersville.
No permanent sampling stations have been established within each reservoir; this reflects the movement of fish species within reservoirs as determined by TVA data from the Browns Ferry Nuclear Plant preoperational monitoring program.Two species, white crappie and smallmouth buffalo, are collected repre-senting both commercial and game species.Sufficient fish are collected in each reservoir to yield 250 to 300 grams oven-dry weight for analytical purposes.All samples are collected quarterly and analyzed for gamma, 30 gross alpha, gross beta activity, Sr, and Sr.The composite 89 90'amples contain approximately the same quantity of flesh from each fish.For each composite a subsample of material is drawn for counting.Results are given in table 18.Plankton As indicated in table 14, net plankton (all phytoplankton and zooplankton caught with a.100 p mesh net)is collected for radio-logical analyses at each of three stations by vertical tows with a.-4-meter.net;At*least 50 grams (wet weight)of material is necessary for analytical accuracy.Collection-of this amount will, probably be practical only during the period April to September (spring and summer quarters)because of'easonal variability in plankton abundance.
Samples are analyzed for gross beta activity and, when quantities are suff'icient, for.gamma activity and Sr and Sr content'.Results are shown in table 19.Sediment Sediment samples are collected from Ponar dredge hauls made for bottom fauna.Gamma and gross beta radioactivity and Sr 89 and Sr content are determined quarterly in composite samples col-lected from each of four" stati'ons., Locations of these stations are shown in table'14.Results are shown in table 20.Bottom Fauna The flesh and shells of Asiatic clams collected from the cross sections at four stations (table 14)are analyzed for gamma and gross beta activity at quarterly intervals.
The Sr and Sr 89'0 contents are determined on the shells, and on the flesh when suf-ficient amounts were availabl'e.
A 50-gram (wet weight)sample provides sufficient activity for counting.Results are given in table 21.
Table 14 SAMPLING SCHEDULE-RESERVOIR MONITORING Tennessee River (Mile)277.98 Zooplankton, Chlorophyll, Biolo ical Sam les Benthic Fauna*Sediment*2-.2 Fish+*Water Sam les Distance From I.eft Bank Depths Feet Percent (Meters)283.94 3600 40 7100 78 1 1, 10 288.78 291.76 5000 60 7000 84 1 1, 5 293.70 6800 65 9200 88 1 1, 5 295.87 307.52 4000 44 7500 82.1800, 24 2800 37 155 1 1, 5 1*Replicate samples~Gill.net and/or electroshocker will be used for collection.
Samples of fish are collected from Guntersville, Wheeler, and Wilson Reservoirs.
32 Figure 4 R ES ER VO I R MONITOR IN G NETWOR K Elk River N WHEELER DAlVl mile 274.90 mile 277.98 Rogersville 0 mile 29l.76 Athens 0 B.F.NUCLEAR PLANT mile 295.87 mile 285.94 0 Courtland ile 28878 mile 295.70 Decatur mile 307.52 Scale*of Miles 0 Table 1S Dissolved Cctivi i liter TN Depth Niver No.of Eoriz.in Cross Nonvolatile 8 if ic Nadionnclidas Nli~l I i N~ll I C C 1 C C\Sr 283.94 2 283.94 2 283.94 2 291.76 2 291.76 2 291.76 2 40 1 ND 78 1 78 10 60 l.84 84 5 2.6 2.2 3.7 ND ND 0.8t0.7 ND ND 1.6t0.6 ND ND ND 3.1t2 3 ND 2.6tl.0 l.ltl;1 1.8tl.3 2.5t0.7 2.1t1.2 ND 3'tl.S$.7tC.3 0.610.3 1.7tO 3 ND 5.8tl.2 4.5t0.9 1.1t0.2 2.1t0.3 3.7t2.0 6.3t1.4 2.3t0.8 O.St0.3 0.90.3 3 Lil.8 ND 4.6tl.2 4.la 1.0 0.5t0.3 0.StO.0 ND S.ltl.3 4.0-1.5 0.4 0.2 3.5t0.3 ND 6.0i4.0 6.6tl.S 4.7tl.l O.lt0.0 2.9W.3 293.70 2 293.70 2 293.70 2 6$88 0.4 2'2.8 1.8 3.4t1.0 ND ND 6.0t0.9-C.lt0.9" 1.St0.3 ND 6.2t3.3 Ce3tlo3 7o3t2.8 0.8t0.3 0.3t0.0 ND$.6t1.4 2.1t1.7 0.8t0.3 0.410.0 295.87 2 C4 29$.87 2 44 295.87 2 82 307.52 2 24 307.$2 2 24 1 ND S ND 1~ND 307.52 2 37 1=ND Avsra~'D 2.3 2.2 2.0 1.8 2.4'D 1:9t0.9 ND 0.2tO.1 0.2tO.2 0.Ct0.1 0.StO.1 0.~.1 ND ND$.2t3.1 4.9tl.l 4.8t1.3 0.6t0.2 0.4t0.3 ND ND ND 3.8t1-3 3.8t1.0 0.2i0.0 0.8-'0.3 ND ND S.lt3.$3.9tl.0 4.8t0.9 0.7t0.3 ND ND 4.1 l.1 3.7t1.0 Q 9tQ 3 0 3tO ND ND ND 5.5t1~S 4.8 f1.2 l.0t0.3 O.liO.0 ND ND ND 3.7tl.2 4.5t1.0 1.4t0.3 ND ND 0.2t0.1 1.7r0.$4;9t0.3-4.3t0.4 0.6t0.1 1 Qt0 1 spercent ot distaoce across river froa left bank looking dovnstrean ss8ensitfvity 1.2 sssNensitivity 1.6 ND-Not detectable Table 16 RIRRR MATER Total Actinic I/liter Ill Depth Riser No.of Boris.in Cross Nonvolatile llil~t I I>>~AI h 5 C C I~C 8 cif ic Radionoclides Ca tr Sb Co lh Rn Co Ba Ia'r$r'gaaae 283.94 2 283.94 2 18.78 283.94 2 40.10 5D 2.7 ND 2.2 1.7 4.9+3.2 ND ND MD SD SD ND ND ND ND ND~ND 1.8c0.5 1.SC1.0 SD ND ND 2'+1.8 SD 7.0t1.3 3.4t1.0 0.3t0.2 0.6t0.3 3.4t1.0 5.1t0.9 SD 1.2t0.3 ND 3.9t0.8 2.4c0.8 0.3+0.2 1.3+0.3 291.76 2 60 291.76 2 84 291.16 2 84 3.2 2.1 4.0 1.0$0.8 SD l.It 1'0 ND hD 2~St 1.1 1.S+0.8 hD ST 3t1.3 3.1 1.1 SD 1.7t0.3 1-0+0.3 hDÃD 3.5c1.4 2.4tl.l 0.3t0.3 O.S 0.3 SD 293.10 2 293.70 2 295.87 2 29S.87 2 44 293.10 2'$.2.3 2.$2.2 1.7 ND ND ND MD ND ND SD ND ND ND ND'4 ND ND ND ND SD ND MD 6 St2.3 ND ND SD 0.9+0.4 SD 5.St2.4 3.8tl.1 4.lt0,1 ND 1.1t0.3 SD SD 5.3 0.9=2.8 0.6 7.0t1.0 ND ND I.S+0.3 0.4+0.3 0.8+0.3 0.6t0.4 ND 4.6t2.6 3.5ti.l 2.8 1.0 0.7t0.2 0.4t0.0 ND'.7+1.0 3.6i1.0 0.3c0.3 0.9 0.3 295.81 2 82 2.6 SD 5D MD ND 1.6C0,7 0.7t0.4 SD 2't0.9 4.1t1.0 0.8t0.3ÃD 307.S2 301.S2 24 301~52 2 24 Arera e: ND 3.0 2.5 2.1 2.3~3 4+2,1 ND ND ND SD SD 0.7CO.S SD 0.6c0.3 MD ND 0.4t0.2 0.4t0.1 0,2+0.04 SD 1.3t1.3 4't0.8 SD 3.1t0.8 3.0-0.7 ND I.S+0.5 3.1t1.5 3.3t0.6 ND 0.3+0.1 0.9t0.3 3.7t0.3 3.1t0.2 0.8c0.3 0.3 0.0 0.5+0.3 0.3c0.3 1.2t0.3 SD 0.4t0.1 0.1t0.1 ND efercent of distance*eSensltiiicy 1.2 eeeSensicivit7 1.6 eeeeSeneit ivies 400 MD-Nor.detectable across river froa left.bank lookin8 dovnscrean
- .35 Table 17 RIVER WATER Ci liter Location No.of~Sam les Alpha*'Av~
Nonvolatile Beta**,'pecific Radionuclides Max.'in.~Av.(Avera e Browns Ferry at discharge location 20.6 2.1 5.7 141 144Ce ,"Cr 13-lI 10 3 106Ru 7 134(.137C"Zr-85Nb 58Co'"Mn Zn 60Co 140Ba 140 80S 89S 3H***ND ND ND ND ND 1.0+0.9 0.8+0.6 ND ND 1.3+1.0 4.1+0.9 4.4+0.7 ND 1.3+0.1'300.5+28.2 Elk River 8.4'1.4 3.4 141 144Ce 51Cr 131I 103 106Ru 134Cs 137Cs"Zr-35Nb Co'4Mn Zn 60Co 140Ba-140La"Sr 88Sr.3H***ND 7.4+3.7 1.0+0.6 ND ND 0.9+0.4 0.7+0.6 ND ND 1.3+1.2 3.5+0.7 4.5+0.6 0.2+0.1 1.2+0.2 ND Avera e: Avera e: 4.6*Sensitivity 1.2**Sensitivity,1.6
- Sensitivity 400 ND-Not detectable Table 18 FISH tl D Vct ht Lotatioa~<<f No.of Cross Cross S ecitic Radtoaucttdcs c of Fish Saaolcs Aloha~Bctacc=Cc Cr I Ru Cs Cs ZT Mb Co?el<<Za Co Ba ta<<Sr<<Sr Cuatersville Saallaouth Buffalo (thole)ND 3.10 ND 0.6t0.12 ND hD ND O.tt0.02 0.2 0.02 ND Ubeeler Saallaoutb Buffalo (Flesh)hhite Crappte (?'lech)Sasllaouth Buf falo (hbolc)Saallaoutb Buffalo (Flesh)ND 6.09 MD O.St0.11 NDÃD 8.38 hD 0.9 0.13 ND 4.87 ND 0.3t0.12 MD ND 6.60 ND hD ND 0.2s0.03 ND hD 0.4t0.04 ND ND O.la0.03 ND ND 0.2S0.02 MD ND hD MD ND ND ND ND 0.1 0.01 0.310.02ÃD Mtl sea white Crappie (Flesh)Saallaouth Buf filo (thole)Saallaoutb Buf falo (Flesh)Vhtte Crappie (Flesh)MD 7.89 MD ND ND MD 4.12 ND ND 4.22!Cl ND 7.82 ND MD 0.3s0.06 ND ND O.ts0.03 ND ND 0.3 0.04 ND MD MD ND MD 0.2t0.02 ND MD MD ND ND 0.la 0.01 MD MD MD MD ND 0.lt0.02 0.2t0.02 0.1 0.08 ND O.lt0.02*Scastttvtty 0.02 c<<Sensitivity 0.03 MD-Not Detectable 37 Table 19 PLANKTON Ci Dr Wei ht Tennessee River Mile 277.98 291.76 307.52 No.of~Sam laa Gross~A1 ha*2.8 2.3-1.5 Gross Beta**18.0 21.5 19.0 Specific Radionuclides***
Avera e: 2.2 19.5*Sensitivity 0.03**Sensitivity 0.04***Sample size not sufficient to perform specific isotopic analysis 38 Table 20 SEDIMENT Ci/Dr Wei ht No.of Samples TN River Mile 277.98 288.78 293.70 307.52~Avere e 4 Gross Alpha*Nonvolatile Beta**0.42 8.02 0.33 7.61 0.35 7.02 0.61 6;94 0.43 7.40 Specific'Radionuclides 1419144Ce 81Cr 131Z 1039106RU 1 34(.s 137Cs Zr-8 Nb 58Co'4Mn 0.3+0.2 0.3+0;2 K9 ND 0.6+0.2 0.5+0.2 0.5+0.2 0.4i0.2 0.2+0.1 0.2+0.1 0.2+0.1 0.2+0.1 0.2+0.1 0.210el 0.120el 0.2+O.l 5.2+0.2 3.4+0.1 2.9+0.1 2.3+0.1 0.2+0 1 0.5+0.1 3.4+0.1 0.2+0.1 0.2iOel Zn 60(o 140Ba 140La 90Sr 89Sr 0.1+0.03 0.2i0el 0.1+0.03 0.2+0.05 0.2+0.0 0.li0.04 ND 0.2+0.04 0.3+O.l 0.2+0.03 0.3+0.04 0.2+0.1 0.2+0.04 0.2+0.01 0.1+0.03*Sensitivity O.ll**Sensitivity 0.15'D-Not detectable 39 Table 21 CLAM Ci/Dr Wei ht Clam Shell TN River Mile No.of Samples Gross Alpha*277.98 0.07 288.78 0.10 293.70 0.14 307.52 0.25~Aireee e 0.14 Nonvolatile Beta**2.7 2.8 2.8 3.5 3.0 Specific Radionuclides
)41~)44Ce"Cr)3)Z)03~)06RU 1 3 4Cs 137(s"Zr-"Nb 5 8(.o 0.5+0.1 ND 0.1+0.03 ND 0.1+0.02 0.5+0.1 ND ND 0.6+0.10.&0.04 0.1+0.02 0.5+0.1 0.3+0.1 0.1+0.03 0.5+0.1 0.1+0.03 0.1+0.01 6SZn 60(o ND ND 0.1+0.02"Sr"Sr La 5.8+0.1 0.7+0.2 5.3+0.1 ND 4 6+0 1 0.3+0.2 0.2+0.02 5.8+0.1 0.4+0.2 5.4+0.1 0.4+O.l*Sensitivity
-0.11'**Sensitivity
-0.14 ND-Not detectable 40 Table 21 (Continued)
CLAM Ci/Dr Wei ht Clam Flesh TN River Mile No.of Samples Gross Alpha*Nonvolatile Beta**277.98 1.02 3.1 288.78 4'.54 1.4 293.70 0.77 1.6 307.52 0.86 2.8~Aveva e 0.80 2.2 Specific Radionuclides 141 144C"Cr 1 3 1Z 10 3~106Ru 134C 13.7Cs Zr-Nb 68Co'4Mn 65Z"Co 140B 140La 90Sr 89S 4.0+1.6 1.0+0.2 0.8+0.2 1.8+0.6 ND l.1+0.2 1.9+0.4 NA NA 1.7+0.5 1.2+0.8 0.2+0.1 0.8+0.2 0.2+0.1 0.4+0.2 ND 0.3+0.1 0.8+0.1 NA NA 2.1+0;8 2.3+1.3 O.1+0,04 0.2+0.1 0.1+0.04 0.2+0.1 0.8+0.1 1.3+0.2 NA NA 2.5+1.1 0.5+0.2 1.4+0.8 0.5+0.4 0.4+0.4 1.L+0.2 1.8+0.3 NA, 2.6+0.5 0.9+0.4 0.4+0.1 0.6+0.2 0.3+0.1 0.7+0.2 0.L+Oe 1 0.8+O.l 1.4+0.1 NA*Sensitivity
-0.03**Sensitivity
-0.04 NA-Not analyzed ND-Not detectable ualit'Control A quality control program has been established with the Alabama Department of Public Health Environmental Health Administra-tion Laboratory and the Eastern Environmental Radiation Facility, Environmental Protection Agency, Montgomery, Alabama.Samples-of air, water, milk, and vegetation collected around the BFNP are forwarded to these laboratories for analysis;and results are exchanged for comparison.
Data Anal sis Data measured at each indicator and control station were averaged for the 6-month reporting period.In order to describe the distribution of control station data, a mean, standard deviation, and 3-sigma value were calculated.
We can expect, with 99 percent con-.fidence, that background concentrations would be distributed within these limits.This provides us the basis for comparing control and indicator data.If the indicator data fall within the limits defined for control data, we can say, with 99 percent confidence, that the indicator data were not significantly affected by the nuclear plant.If the data do not fall within the limits, we will perform further analyses to.determine if the difference is attributable to the nuclear plant.Conclusions A vast majority of the indicator station data were found to be within the distribution defined by the control station data.The Alpha-M least squares computer program identified concentrations slightly exceeding the limits of the control station data for a small number of radionuclides in samples from indicator stations.Many of these values may be discounted because the error reported by the Alpha-M program was greater than the calculated concentration.
The remaining isolated elevated concentrations may be the result of fallout, computer program artifacts, or analytical errors.The same type of isolated high values occurred in the control station data and may be attributed to the same sources.~Increased levels of iodine-131 were found in milk in September 1974, with a maximum value of 1.4 pCi/1.Similar elevated values were reported at other locations around the country during that period, indicating a possible increase in fallout.It is probable that the activity is due to the surface component of the Chinese nuclear bomb test late in June 1974.
42 Exposures were measured with thermoluminescent dosimeters (TLD)at nine indicator stations near the site boundary and at eight control stations remote from the plant.Some anomalies were observed in the TLD exposure measurements at both indicator and control stations.However, these were measured during the quarter when increased radioactivity from the Chinese test'as expected., The average exposure computed for each indicator station was found-to be, within the background levels defined by the control station.data.'