PEL 216

ATOMIC ENERGY BOARD

ENVIRONMENTAL RADIOACTIVITY AT THE NATIONAL NUCLEAR RESEARCH CENTRE, PELINDABA

REPORT FOR THE YEAR 1970

BY

D. VAN AS CONSTANCE M. VLEGGAAR

PELINDABA REPUBLIC OF r OCTOBER, 1971 5 PEL 216

ATOMIC ENERGY BOARD

ENVIRONMENTAL RADIOACTIVITY AT THE NATIONAL NUCLEAR RESEARCH CENTRE, PELINDAPA

REPORT FOR THE YEAR 1970

by

D. van As* Constance M. Vleggaar*

* Isotopes and Radiation Division

PELINDABA POSTAL ADDRESS: Private Bag 256, September, 1971 PRETORIA. OPSOMMING ABSTRACT

'n Hersiene omgewingsmoniteerprogram, toegespits op monitering van kritieke A revised environmental survey programme, with the emphasis on monitoring of paaie waardeur die algemene publiek aan raoioaktiwiteit blootgestel kan word, is ge- the critical paths of exposure of the general public, was introduced during the period durende die verslagtydperk in werking gesteL covered by this report. Resultate van bepalings van totale radioaktiwiteit asook van afsonderlike nukliede Results of determinations of both gross radioactivity and of individual nuclides in in monsters van vis en water (die kritieke materiale vir vrygelate vloeibare radio- samples of fish and water (which are critical materials for liquid effluent releases) from aktiewe afval) uit die Hartbeespoortdam en die Krokodilrivier afkomstig, word verstrek. the Dam and from the Crocodile River, are given and discussed. Ewe-eens word resultate van gammaspektrometriese en ^Sr-ontledings van melk, Results of gamma-spectrometric and ^°Sr analyses of milk, the critical material die kritieke materiaal vir vrygelate gasagtige afval, aangebied. for releases to the atmosphere, are presented. Die resultate van gereelde ondersoeke na die samestelling van vrygelate afval om Results of regular investigations of the composition of effluent releases, which are moontlike nuwe kritieke nukliede te kan opspoor, word ook verstrek, performed in order to be able to detect possible other critical nuclides, are given. Konsentrasies van radioaktiwiteit in neerslag en in lug, van kernbomtoetse afkom­ 1 .eveIs of deposited and airborne activity from nuclear bomb tests are reported. stig, word weergegee.

/$6^; o ?£9£c /zz9 CONTENTS

Page

1. PROGRAMME 6 1.1 Measurements ° 2. RESULTS AND DISCUSSION 6 2.1 Gamma Survey ° ACKNOWLEDGEMENT 2.2 Milk 6 2.3 Fish 7 The authors wish to express their thanks to 2.4 Water 7 Dr. J.K. Basson - for his continued interest in the enviion- 2.5 Sediment 7 (Director: Isotopes and Radiation) mental programme, 3. RADIOACTIVE EFFLUENT RELEASES TO THE ATMOSPHERE Mr. A.S. Robinson - who was responsible for the chemical AND THE CROCODILE RIVER 7 analyses, 3.1 Releases to the Atmosphere 7 3.2 Liquid Releases to the Crocodile River 7 Mr. P.S. Bothnia and - who were responsible for the collection 4. CONCLUSIONS 8 Mr. T.G. Prinsloo and preparation of samples as well as APPENDIX 8 the measurement of gross radioactivity. REFERENCES 9 TABLES

J Ftl. 216- 6 PI I _>ic> - 7

1. PKOGKAMMI i.e. Tilapia Mossambica, Cyprinus Carpio and Clarias value of 126 pCi/I was measured at the beginning of June, and Samples from the dam, from the river and of drinking water Mossambica from the and Crocodile measurable ,3lI concentrations in milk lasted until the end The survey of environmental radioactivity in and showed no activity other than natural k. In most cases River. Bulked samples of a particular species are measured of September. This period of high l31I levels in milk coin­ around the National Nuclear Research Centre at Pelindaba the Cs levels were below the minimum detectable level 90 cided with a series of French nuclear bomb tests in the l37 40 was started in 1964 and previous results were published in for gross beta activity, Sr and gamma-emitting nuclides. of 0,1 pCi/L The measured ^Sr, Cs and K concen­

1-3 Southern Pacific Ocean and fresh fallout products were de­ a series of Pelindaba reports' *. The procedures for 1.1.4 Monthly sampling of drinking water from the Kosmos/ trations are given in table IX. tected over the whole of Southern Africa. sample taking, sample preparation and activity measure­ Schoemansville area and analyses for residual beta activity 2.5 Sediment An intensive monitoring programme of both milk and ments are described in these reports as well as in PEL (total beta minus ^K activity), ^Sr and gamma-spectro- Sediment samples from the Hartbeespoort Dam and air samples in Cape Town and at Pelindaba enabled the 109 . A review article by Van As and Basson* ' has been metric analyses on quarterly bulked samples. the Crocodile River were collected during December, 1970 authors to determine the relationship between * I concen­ published» discussing the purpose, extent and value of the 1.1.5 Monthly sampling of water from the Crocodile River to indicate the possible sedimentation of released activity. trations in air and that in milk under conditions of both dry environmental monitoring programme. More detailed re­ at a point above our effluent release point, with analyses as The gross beta activities were normal and comparable to fallout and washing out by rain (9). From these results it sults on fallout radioactivity in South Africa are reported for drinking water. the values for previous years. No gamma-emitting nuclides appears that the maximum permissible concentration of 13lI in articles by Basson, Van As, Van der Westhuizen and Because of the problems encountered in trying to ob­ other than ,37Cs and *°K were detected. The results of these in air would lead to a milk concentration which is a factor Vleggaar*°) and by Van As and Basson ' . tain representative fish samples from the river-dam com­ determinations are presented in tables X and XI and show i3 500 to 900 times in excess of the derived working limit for In the report for 1969, PEL 205 \ a revised pro­ plex, indicator materials which are easier to sample or have no significant changes from previous years. gramme was suggested which places the emphasis on the higher concentration factors may also be gathered and milk, depending on whether dry fallout or rainout persists. analysed. No increases in radioactivity in milk could be detected monitoring of only those materials which, due to their pro­ 3. RADIOACTIVE EFFLUENT RELEASES TO THE due to releases from the NNRC. ^Sr and 1 Cs levels perties of concentration of hazardous nuclides and their use 1.1.6 Quarterly sampling of water from the Hartbeespoort ATMOSPHERE AND THE CROCODILE RIVER and/or consumption by the population, would be the principle Dam from four representative points with analyses for (table III) were not significantly different from those of

W previous years. 3.1 Releases to the Atmosphere routes, i.e. critical paths, through which human beings residual beta activities on individual samples and Sr and 2.3 Fish would be exposed. This programme was implemented during gamma-spectrometric analyses on quarterly bulked samples. Releases to the atmosphere are monitored in the 1970 and the results are given in this report. 1.1.7 Annual sampling and analyses of sediment at the in­ Samples of fish from the different edible species in reactor stack and the waste disposal building stack by (8) As critical paths may vary according to the compo­ flow to the Hartbeespoort Dam of the Crocodile River, and both the Hartbeespoort Dam and the Crocodile River were means of May packs which are changed and measured for 131 sition of releases to the environment, monthly bulked samples in the Crocodile River itself. collected during February, April, August and November. The gross alpha, gross beta and I (particulate and gaseous) of liquid effluent were analysed to determine the presence species Cyprinus Carpio was scarce and could only be ob­ on a weekly basis. Whenever normal background levels are of individual nuclides. Weekly samples of airborne effluent 2. RESULTS AND DISCUSSION tained during November. The gross beta activity in the fillet exceeded, gamma-spectroscopic analyses are performed. released through the reactor stack and the waste disposal of the different species are given in table IV. These values No monitoring is normally done for gaseous activity other Gross alpha activity is expressed as the equivalent (8) .K I31l building stack were collected by means of May packs . 241 are normal and show no significant change from previous Am activity and gross beta activity as the equivalent than I.

Individual elements of this monitoring system were measur­ years. 10 204TI activity, i.e. 2,3 the equivalent ^K activity. The measured releases are given in table Xlr \ As ed for gross alpha activity, gross beta activity and * I. 2.1 Gamma Survey Bulked samples were analysed by gamma spectro­ the maximum permissible levels of releases for unknown Whenever appreciable amounts of gross activity are detected, scopy. Only the fission product 137Cs (most probably orig­ alpha emitters are 118,4 mCi/month and that for unknown The gamma survey serves the purpose of establishing more detailed analyses for individual nuclides are made. inating from deposited fallout} and the naturally occurring beta emitters 2,96 Ci/month, it can be calculated that, re­ a network of points of known background activity which, in 40K could be observed. The concentrations of ^Sr,I3 Cs lative to the permitted values, the actual releases were only case of an emergency, can be used for a rapid determination 1.1 Measurements and 40K 0,001% in the case of alpha emitters and 0,08% for beta of the extent of the contaminated area. No significant vari­ are given in table V. The present environmental programme consists of: emitters. ations from the radiation levels measured in previous sur­ 2.4 Water 3.2 Liquid Releases to the Crocodile River 1.1.1 Annual measurement of gamm* radiation at 77 points veys could be detected (table I). The gross beta activity in drinking water from the Releases to the Crocodile River are reported in ac­ inside the exclusion area and at 96 points along 9 routes in 2.2 Milk Kosmos/Schoemansville area, in background water samples the vicinity of the NNRC, up to distances of 30km from the from the Crocodile River and in water from the Hartbees­ cordance with perm it 8 No. 220 B and 250 B from the Depart­ The gamma-spectrometric analyses of I31I in two- reactor. poort Dam are given in tables VI, VII and VIII respectively. ment dl Water Affairs. According to these permits all alpha weekly milk samples were commenced in May, 1970. A lower 1.1.2 Two-weekly monitoring of milk from 10 farms in all In all of these samples, 4°K constitutes 70-80% of the gross activity is calculated as being due to Ra and all beta 131 wind directions up to distances of 8 km from Pelindaba. limit of detection of 20pCi I/1 can be attained with this beta activity. The residual beta activities of these water activity as being due to 9°Sr, unless analyses for the indi­ Bulked samples are measured by gamma spectroscopy for method. This lower limit enables one to measure down to samples are very similar and no increase in either the vidual nuclides are performed. The total activity released 13I1. Three-monthly bulked samples are measured for^°Sr 5% of the derived working level for 131I in milk, e.g. 400 activity of water from the Dam or in that of drinking water, is calculated as follows: and Cs. pCi/L due to releases from the NNRC, could be detected, (226Ra x 200) • (other a-activity * 2,86) • ftr * 20) • 1.1.3 Quarterly sampling of the general edible fish species, During the period of monitoring (table II), a maximum Gamma-spectrometric analyses on quarterly bulked (other 0 -activity xl) PEL 216-8 PI I :>ln - i>

According to the permit from the Department of Water detected in the environment. REFERENCES Affairs, the total activity released may not exceed 4,54 Ci per 13 consecutive weeks. APPENDIX 1. VAN AS, D. : Atomic Energy Board, PEL 51, PEL 63, 5. VAN AS. D. and J.K. Basson : S. Afr. I. Sci. 65, 3-16 This method of calculating releases to the Crocodile PEL 66, PEL 89, PEL 105, PEL 123, PEL 140 (1964 Measurement of Nuclear Bomb Fallout in (1969). River is convenient for administrative purposes and very - 1967). Air and Deposition. 6. BASSON, J.K., D. van As, M. van der Westhuizen and conservative as concerns the control of permissible levels 2. VAN AS, D., H.O. Fourie and Constance M. Jordaan : Constance M. Vleggaar : S. Afr. J. Sci. 66, 214-224 As radioactive debris from nuclear bomb tests con­ of different radioisotopes in drinking water. However, Atomic Energy Board, PEL 160 (1967) and PEL 179 (1970). tribute to the environmental radioactivity background it is drinking water need not necessarily be the critical path. (1968). necessary to take these concentrations into consideration 7. VAN AS, D. and J.K. Basson : Health Physics 14, 307- Because the composition of effluent may vary due to differ­ when investigating the contribution from the NNRC to the 309 (1968). ences in reactor operation or the research activities on the 3. VAN AS, D., H.O. Fourie and Constance M. Vleggaar : environmental levels of radioactivity. site, it is imperative that the different individual isotopes Atomic Energy Board, PEL 181 (1968), PEL 192(1969), 8. KRUGER, J. : Internal Report NAT/CONT 2/70. PEL 205 (1970), PIN 24(BR) (1969), PIN 64(BR) (1970) present in the effluent be known, in order that possible Monthly measurements of individual nuclides measur­ 9. VAN AS, D. and Constance M. Vleggaar : Health Physics and PIN 104(BR) (1971). critical paths can be identified in advance of a critical situ­ ed in deposited fallout and in air samples collected at 21, 114-116 (1971). ation. Pelindaba, are given in tables XIV and XVI. A summary of 4. FOURIE, H.O. : Atomic Energy Board, PEL 109(1966). 10. KRUGER, J. : Private Communication. Since August 1970 representative samples of the quarterly concentrations of ^Osr and ^7Cs in deposited monthly released effluent were analysed gamma-spectro- fallout, as well as the total rainfall, is given in table XV. scopically and the results are given in table XIII. It is An increase in airborne activity occurred during

notable that a number of non-fission products, e.g. 65zn, May, the concentrations reaching a maximum in August and Na, Mn and °^Co are present in the effluent. decreasing again afterwards. This sudden increase in May was the result of a nuclear bomb test series in the Southern 4. CONCLUSIONS Pacific Ocean which commenced on 15th May and was ter­ minated on 6th August. The short-lived fission products No increases in the radioactivity of the environment 140Ba, 141Ce, *°3RU and 131I were not present prior to due to the operations at the NNRC could be detected. May and clearly indicated the arrival of fresh debris from Increases in the ^I activity of milk and the presence

137 these tests. of the fission products Cs and ^Sr in milk, fish, water and sediment samples can be ascribed to fallout from nu­ Levels of deposited activity was closely related to clear bomb tests. the rainfall and .peak concentrations appeared in October Activation products and other non-fission products when high rainfall was recorded and appreciable levels of activity released in effluent from the site could not be airborne radioactivity were still present in the atmosphere IM I 210 - 10 IM I 210 - 11

GAMMA SURVEY 3. Routes

TABLE 1 Route A Pretoria -

1. Area enclosed by Security Fence Milestone Point Y-counts/s Milestone Point Y-counts/s

Point Y-counts Point V-counts Point Y-counts J West Rand 1 29 19,0 13 63 /s /s /s road exit 19,5 14 42 point in city 20,0 15 61 100 65 108 52 116 52 Atteridgeville 2 41 20,4 16 40 101 70 109 64 117 75 crossing 21,0 17 47 102 62 110 54 118 53 7.9 3 46 22,0 18 35 103 74 HI 41 119 70 10,2 4 45 22,4 19 63 104 47 112 51 120 72 11,5 5 42 23,0 20 23 105 56 113 58 121 45 12.7 6 37 24,0 21 22 106 48 114 57 122 41 13.9 7 43 25,0 22 22 107 46 115 54 123 44 14.8 8 44 26,0 23 23 15.8 9 48 27.0 24 20 17/) 10 49 28,0 25 22 18.0 11 44 28,7 26 23 18.4 12 50

Route B Johannesburg (Bryanston) - Schoemansville

2. Exclusion Area Milestone Point Y-counts/s Milestone Point Y-counts/s Point Y-counts Point Y-counts Point Y-counts /8 /s /s 0,0 10 33 9.9 17 56 3,0 11 20 12,0 18 27 1 74 34 40 56 54 4,0 12 15 13,5 19 23 3 69 35 34 57 62 5,0 13 13 15/) 20 25 5 71 37 46 59 48 6,0 14 16 16.0 21 22 6 62 38 50 60 63 7,0 15 18 18,3 22 24 7 62 39 58 61 48 8,9 16 26 11 60 40 37 64 46 16 32 41 31 65 64 19 42 43 32 68 58 ?0 70 44 38 69 74 21 70 45 42 70 78 22 80 46 34 73 68 23 72 47 25 75 78 Route C Pretoria (Erasmia) - Krugersdorp 24 71 48 41 76 73 27 76 49 32 77 11 29 36 50 24 78 72 Milestone Point Y-coums/s Milestone Point Y-counts/s 30 42 53 35 80 57 31 40 54 42 82 56 5,5 1 26 24,0 7 34 32 42 55 46 93 24 9,0 2 19 27,0 8 42 94 60 12/) 3 19 31/) 9 46 15/) 4 32 34,0 10 52 18/) 5 39 35,9 11 30 21/) 6 30 •••*••«••• * BON ACCORD DAM

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GERMISTON RIVERS a—» MAIN ROADS • SECONDARY ROADS - ROUTE A ROUTE B »»*»» ROUTE C ^^^ ROUTE 0 ROUTE E ~~~~~ ROUTE F

ROUTE G ROUTE H -.,... ROOTE J

PROPOSED EXTENSIONS Pi:I. 216-12

Route H (Hartbeeshoek) - Krugersdorp Route D Schoemansville - Hekpoort

Milestone Point Y-counts/s Milestone Point Y-counts/s Milestone Point Y-counts/s Milestone Point Y-counts/s

1.0 1 66 22,5 5 25 43.3 1 21 9,6 7 36 3,0 2 54 18.8 6 68 41.7 2 22 11,9 8 23 27.9 3 25 10,0 7 63 . 4.9 3 19 13,1 9 27 25.0 4 28 6.0 8 22 6.1 4 22 14,1 10 23 7.5 5 23 19,0 11 24 8.6 6 25 24,0 12 27

Route E Broederstroom (Santa Barbara) - Johannesburg

Milestone Point Y-counts/s Milestone Point Y-counts/s

14,0 1 25 6,0 4 35 10.0 2 26 4.0 5 33 8.0 3 24 1,0 6 40 Route J Brits -

Milestone Point Y-counts/s Milestone Point Y-counts/s

0,3 1 13 31,0 4 17 3,0 2 8 27,0 5 21 Route F Pretoria-North - Brits 6,0 3 14

Milestone Point Y-counts/s Milestone Point Y-counts/s

1,3 1 18 15,0 4 21 5,0 2 19 19,0 5 19 10,0 3 21

Route G Pretoria (Hercules, Swartspruit) - Brits

Milestone Point Y-counts/s Milestone Point Y-counts/s

4,8 1 28 9,1 6 17 7,0 2 24 4,0 7 14 12,0 3 31 2,0 8 13 16,0 4 26 0,4 9 34 18,0 5 22 MILK

TABLK II """I ACTIVITY IN MILK

Activity Activity Date Date in pCi/1 in pCi/1

19.5.1970 26 8.9.1970 49 2.6.1970 126 22.9.1970 22 16.6.1970 85 5.10.1970 < 20 30.6.1970 59 19.10.1970 < 20 14.7.1970 56 2.11.1970 < 20 30.7.1970 NM 16.11.1970 < 20 10.8.1970 41 30.11.1970 < 20 25.8.1970 37 14.12.1970 < 20

NM - not measured

TABLE III INDIVIDUAL NUCLIDES IN MILK

Activity in pCi/1 Period

90„ 40 131 Sr 137Cs K 1

Jan. - Mar. 2,20 4 1072 NM Apr. - Jun. 1.94 5 992 NM JuL - Sep. 2,51 3 1172 41 Oct. - Dec. 3,46 4 1340 <20

NM - not measured WATER

TABLE VI BETA ACTIVITY IN DRINKING WATER FROM SCHOEMANSV1LLE

Activity in pCi/ I

Month 40 Gross B K as Residual 0 204_. 204,., 204 Tl eq. <°K Tl eq. TT1l eq.

Jan. NM NM NM NM Feb. NM NM NM NM Mar. 16,2 7,4 16.6 0 Apr. 20,1 6,6 14,8 5,3 May 20,7 7,3 16,4 4.3 Jun. NM NM NM NM JuL 22,2 7.0 15.8 6.4 Aug. 23,6 7,4 16,7 6.9 Sep. 24,9 6,9 15,5 9.4 Oct. 20,7 7.5 16,9 3.8 Nov. 25,9 7.6 17,1 8.8 Dec. 24,9 7.8 17,6 7.3 Average 5,8

NM - not measured

TABLE VII BACKGROUND ACTIVITY IN WATER FROM THE CROCODILE RIVER

Activity in pCi/1

Month 40^ Residual 8 Gross P K as K 204^, ^if 204^, 204T1 Tl eq. K Tl eq. Tl eq.

Jan. 20,5 6,2 13,9 6,6 Feb. NM NM NM NM Mar. 21,4 7,0 15,7 5,7 Apr. 19,0 7,0 15,7 3,3 May 18,1 7,8 17,6 0,5 Jun. 26,1 9.6 21,6 4.5 Jul. 18,0 8,7 19,6 0 Aug. 24,9 8,6 19,3 5,6 Sep. 26,7 10,1 22,7 4,0 Oct. 27,4 9,1 20,5 6,9 Nov, 29,1 7,1 16,0 13,1 Dec. 31,8 10,2 23,0 8,8 Average 5,4

NM - not measured IM ! L'lo - 14 PEL 216 - 18 TABLE IX INDIVIDUAL NUCLIDES IN BULKl.D TABLE VIII BETA ACTIVITY IN WATER FROM THE HARTBEESPOORT DAM VATER SAMPLES

Activity in pCi/1 Activity in pCi/1 Location Period

ê 90_ 137 4 Month Point Sr Cs 40 °K K as Residual B Average Gross P 4 204_. °K 204T, 2°4^, Schoemansville Jan. - Mar. 0,5 <0,1 7,4 Tl eq. Tl eq. Tl eq. Apr. - Jun. 0,2 0,1 7,0 Jul. - Sep. 0,4 <0,1 7,1 1 24,3 6,8 15,3 9.0 Jan. Oct. - Dec. 0.4 <0,1 7,6 2 20,8 6,0 13.5 7.3 5.9 3 16,2 6,0 13,5 2.7 Crocodile River Jan. - Mar. 0,4 0.1 6,6 4 19,5 6,6 14.9 4.6 Apr, - Jun. 0.4 <0,1 8.1 JuL - Sep. 0,1 <0,1 9,1 Feb. 1 18,5 5,7 12,8 5,7 Oct. - Dec. 0,2 <0,1 8,8 2 18,7 6,0 13,5 1.2 5.2 3 19,2 6,0 13,5 5.7 Hartbeespoort Dam Jan. - Mar. 0,3 <0,1 8.4 4 17.3 5,9 13,3 4.0 Apr. -J Jun. 0,2 <0,1 7.8 JuL - Sep. 0,2 <0,1 7,6 Mar. 1 27,1 13,8 31,1 0 Oct. - Dec. 0,2 <0,1 7.8 2 NM NM NM NM 0 3 19,8 11,6 26,1 0 4 21,6 13/) 29,3 0

Jun. 1 21,9 9.4 21,2 0,7 2 22,0 8,4 18,9 3.1 2.9 3 19,0 7.0 15,8 3.2 4 19,0 6,5 14,6 4.4 SEDIMENT Aug. 1 21,7 8,6 19,4 2.3 2 21,6 6,9 15,5 6.1 5,0 TABLE X ACTIVITY IN SEDIMENT FROM THE 3 21,9 7,1 16,0 5,9 HARTBEESPOORT DAM 4 21,3 7.0 15,8 5,5

Sep. 1 25,7 8,9 20/) 5,7 2 26,6 7,2 16,2 10,4 7.4 3 22,0 7,2 16,2 5,8 Activity in pCi/g 4 24,8 7,6 17.1 7,7 Month 9,7 Dec. 1 31,8 9,8 22,1 90o 137„ W 2 23,4 6,0 13.5 9,9 8.8 Gross p Sr Cs K 3 25,0 7,7 17,3 7,7 4 25,0 7,6 17,1 7,9 Dec. 47 0,1 <0,1 16 Average 5,0

NM - not measured IM I PEL 21o- 20 DEPOSITED FALLOUT

TABLE XI ACTIVITY IN SEDIMENT FROM THE TABLE XIV MONTHLY ACTIVITY IN DEPOSITED FALLOUT CROCODILE RIVER Activity in mCi/km^ per month Rainfall Month Activity in pCi/g in mm 95 90_ Ï37 M4 106 140n 103 141 Sr C0 s Ce Ku Ba vZ r Ce Month Ku 90- Jan. 88,3 0.150 1,02 0,55 0 0,100 0 0 Gross 0 Sr ^7CS WK Feb. 39.8 0.19 0,069 0,72 0,27 0 0,029 0 0 Mar. 38.1 0,071 0,62 0,154 0 0,023 0 0 Nov. 67 0.4 0,2 15 Apr. 41.3 0,036 0,36 0.161 0 0 0 0 May 17,0 0,12 0,039 0,46 0.145 0,131 0,081 0 0,102 Jun. 12.4 0,030 0.75 0,36 1,43 1,07 1,01 0,88 JuL 0 0,015 0,25 0,181 0,57 0,45 0,36 0,48 Aug. 1.8 0,07 0,026 0,47 0.27 0,89 1,34 0,60 0,78 Sep. 17.4 0,074 1,30 0,95 1.54 5.17 2,73 2.36 Oct. 76.5 0,25 3,31 1,68 1,26 12.1 4,45 3,47 Nov. 50.6 0,37 0,190 2,45 1,05 0,41 6,00 1.66 1,59 EFFLUENT RELEASES Dec. 96,1 0,180 2,23 0,98 trace 4,52 0,88 0," i |

TABLE XII EFFLUENT RELEASES TO THE ATMOSPHERE

TABLE XV QUARTERLY ACTIVITY IN DEPOSITED FALLOUT Activity in mCi 2 Period Activity in mCi/km per quarter "ainfall 131 Period or 0 -Y I* in mm 90_ 137 Sr CS Jan. - Mar. 0,002 25,46 25,4 Apr. - Jun. <0,1 0,182 0,151 Jan. - Mar. 166,2 0,57 0,29 Jul. - Sep. 0,003 0,99 0,9 Apr. - Jun. 70,7 0,36 0,11 Oct. - Dec. 0,002 0,15 0,13 Jul. - Sep. 19,2 0,21 0,12 Oct. - Dec. 223,2 1,10 0,62 Annual total 479,3 2,24 1.14 | * Included in 0-y activity

AIRBORNE ACTIVITY

TABLE XVI MONTHLY ACTIVITY IN AIR TABLE XIII EFFLUENT RELEASES TO THE CROCODILE RIVER Activity in pCi/kg air Month 137„ 144„ 106„ 140„ 95 103„ 141„ 131. Cs Ce Ru Ba Zr Ru Ce I* Activity in mCi Month Jan. 0,0026 0,023 0,0106 0 0,0023 0 0 0 Feb. 0,0019 0,0158 0,0092 0 0,0013 0 0 0 m 22 °0„ 65, c. '"c Na Co Zn Mar. 0,0021 0,0148 0,0100 0 0,-0010 0 0 0 Apr. 0,0011 0,0082 0,0053 0 0,0004 0 0 0 Aug. 0,059 0,21 NM NM NM May 0,0021 0,026 0,0108 0,131 0,093 0,081 0,093 0,079 Sep. 0,008 0 NM NM NM Jun. 0,0025 0,037 0,032 0,196 0,147 0,156 0,155 0,066 Oct. 0,054 0,021 NM NM NM Jul. 0,0046 0,098 0,039 0,31 0,50 0,33 0,38 0,092 Nov, 0,68 0,115 2,72 NQD NQD Aug. 0,0059 0,134 0,048 0,34 0,65 0,35 0,42 0,104 Dec. 0,16 0 0,87 NQD NQD Sep. 0,0055 0,104 0,048 0,131 0,43 0,24 0,24 0,029 Oct. 0,0038 0,072 0,028 0,021 0,20 0,093 0,086 trace Nov. 0,0044 0,075 0,028 0,0094 0,170 0,056 0,049 0 Dec. 0,0036 0,060 0,027 trace 0,112 1 0,029 0,023 0 NM - not measured NQD - present but not quantitatively determined •Particulate component