SSI-rapport 86-12 11111111111 St ltens llll lskyddsinstitut Postadress Gatuadress Telefon Box 60204 10401 STOCKHOLM Karolinska sjukhuset Solna 08 -244080 ' 1 08 -20 Shernobyl - its impact on Sweden ISSN 0282-4434 Price SEK 00 Title page NATIONAL INSTITUTE OF RADIATION PROTECTION Document nwnber SSI-rapport 86-12 STATENS STRALSKYDDSINSTITUT ISSN 0282-4434 Date August 1 1986 Author Division Title of the document Chernobyl - its impact on Sweden Abstract In case of a radiological emergency in Sweden the Swedish National Institute of Radiation Protection SSI has the responsibility of organ1z1ng a special task force with experts both from SSI and from other authorities Reports of increased radiation l eve ls reached SSI around 10 am on April 28 1986 and the task force convened at 1030 am A large number of measurements were made all over the country and temporary grazing restrictions were imposed so as to avoid excessive doses from the food chain grass -cow-milk Attention is now concentrated on regions with high ces ium activity and on foodstuffs 1n general A very tentative estimate of the collective dose commitment is 10 000 man Sv It turned out that the general public was not always satisfied with th e information provided by the authorities in spite of complete openness Keywords chosen by the author Che rnobyl Accident Measurement Countermeasure Nwnber of pages 24 Stockholm August 1986 To the readers of CHERNOBYL - ITS IMPACT ON SWEDEN This is the first comprehensive publication in English dealing with the radiation risks in Sweden from the Chernobyl accident and the countermeasures taken It purports to give an overview of the very extensive information that is available from Sweden in various publications as well as in the form of raw data The expected readers are radiation protection experts in other countries and in international organisations Data and analyses have been presented in English also from other Swedish bodies such as the National Defence Research Institute and the National Food Administration The report contains addresses to several such organisations An elementary description of the accident consequences has been published by the Swedish National Institute of Radiation Protection It is a direct translation of a report aimed at the various non specialist Swedish authorities handling the accident consequences The report is entitled ''Chernobyl - fallout measurements and consequences This publication in English might be of interest also to specialists as an example of a simplified account of the events Scientific reports on what happened in Sweden will continue to appear at conferences in scientific journals and so on Several articles have already been prepared for publication and a large number of scientific institutions are involved Gunnar Bengtsson Director General Swedish National Institute of Radiation Protection Chernobyl - Its Impact on Sweden 1 Emergency organization The organization for radiological emergencies in Sweden is mainly based on the needs that may arise from the 12 reactors in the national nuclear power program The organization has a regional character in that the responsibility in an accident situation rests with the highest county authority - the county council - in each of the five counties in which there is a major nuclear installation the four power plants Oskarshamn Barseback Ringhals and Forsmark and the Studsvik research center In case of an emergency each of these county councils has at its disposal the county alarm center the local radio stations and the police coast guard and fire-fighting organizations Special communication channels between the various authorities and the Nuclear Power Facilities have been installed and extensive training of the relevant personnel categories has taken place On the national level the National Institute of Radiation Protection SSI has the overall responsibility for the emergency planning outside the nuclear power plants and for providing the county authorities with advice and instructions for planning In the event of an accident the SSI shall give advice to the county council rescue command For that purpose the SSI has the responsibly of organizing a special task force with radiation protection experts from the institute reactor engineering experts from the Nuclear Power Inspectorate SKI and specialists in meteorology and protection of the population The tasks for this group are to analyse the emergency situation give prognoses of the radiological consequences and to coordinate the various activities with measuring ionizing radiation This task force is also supposed to be called in for all emergencies or accident situations in which the radiation of the public from ionizing radiation must be taken into consideration the exception of the special task force at SSI the emergency planning described above covers only emergencies and accidents in the Swedish nuclear power industry and 5 out of Sweden's 24 counties In other nuclear emergencies of non-domestic origin the nuclear counties may extend their authority to neighbouring ones For the country at large the Government takes the responsibility through the National Institute of Radiation Protection Situations of this kind arose in the early 1960s when considerable fall-out from aboveground weapons testing was foreseen More recently there have been two instances when there was a risk that nuclear-powered satellites would reenter the atmosphere over Swedish territory The latest situation is that arising from the Chernobyl accident and this has put the heaviest demand on the organization so far ith 2 2 Early chronology of the Chernobyl emergency At around 10 a m on April 28 the SS was notified that increased radiation levels were observed at the Forsmark nuclear power plant The local county alarm centre was also notified Gate monitors had sounded the alarm as employees were leaving the plant after having crossed open ground between the buildings and the gate Although no abnormal radiation l evels were observed insi de the reactor buildings or from the stacks a plant alert was declared resulting in the evacuation of all personnel not required for the immediate operation of the plant The local radio station was informed of the observations and the measures taken The SS special emergency task force was convened at the SSI Stockholm headquarters in accordance with preexisting plans at 10 30 a m Shortly thereafter information was received about abnormal radiation levels at the Studsvik research center about 200 km down the coast from Forsmark Contact was established with the other three nuclear power plants who also during the afternoon reported inreased air and ground activity in their vicinity In addition contacts were taken with the Finnish Centre for Radiation and Nuclear Safety and with the Riso Research Centre in Denmark They confirmed that increased background radiation and airborne contamination had been registered in both Finland and Denmark The National Defence Research Institute FOA operates a national network of highly sensitive air sampling stations designed for verification of nuclear test bans When FOA at 12 15 was notified of the presumed release at Forsmark they immediately analyzed the sample just taken from the Stockholm station From several radionuclide ratios it was evident that a reactor accident had occured somewhere The FOA system incorporates a link to SMHI the Swedish Metrorological and Hydrological Institute on which automatically each morning receptor oriented air parcel trajectories are transfered The Stockholm trajectories that morning sshowed the air coming from Latvia Lithuania White Russia and Ukraine in the Soviet Union All Swedish reactors could thus be excluded and several sites in USSR Ignalia Rovno Chernobyl Kursk and Novovoronezhiskiy were according to this analysis candidate accident sites These conclusions were reported to SSI around 1300 The FOA air sampling network consists of several stations around the country Fig 1 The filters are normally changed three times a week but starting on April 28 samples were taken much more frequently for periods of 1 - 3 hours In these early filters around 40 different radionuclides were identified 3 The FOA surveillance system also includes air filter collectors which can be mounted under the wings of ''Lansen jet fighter aircraft flown by the Air Force On the afternoon of April the 28th these planes collected samples along the eastern border 300 m above the Baltic Sea A scan was also made at different altitudes up to 12 km This was done partly to exclude the remote possibility of the event being due to accidental reentry of a reactor powered satellite Direct in-cloud measurements were carried out by FOA in the evening of the 28th utilizing a mobile germanium spectrometer on a Marine helicopter On that flight doserate meters also showed the contaminated cloud to be between 200 and 1000 m above sea level with a maximum at around 700 m Dating from the times of frequent above-ground weapons testing around 1960 the SSI has had a network of 25 permanent continuously registering gamma stations Fig 1 A systematic collection of data from these stations was initiated already before lunch The SSI emergency organization was succ ssively enlarged to include experts from the Nuclear Power Inspectorate SKI the National Defense Research Institute FOA the National Board of Civil Defence Cfs and the National Institute for Meteorology and Hydrology SMHI Many external organizations were drawn upon for measurements FOA the nuclear power stations the Swedish Geological Co SGAB the Department of Radiophysics at the University of Lund and many other research institutes The SSI emergency center was manned around the clock for the first few weeks As the fall-out situation became clearer cooperation was established with the national authorities for food administration agriculture and occupational health 3 Measurements and results Ground and air measurements The radiation level started to rise at some of the gamma stations on April 27 as the first cloud of contaminated air from the Chernobyl accident reached Sweden The air activity reached a maximum around April 29 Another cloud of contaminated air entered Sweden from the south-east resulting in a lesser maximum in air contamination around May 9 This second maximum affected mainly the south and south-west parts of Sweden During the first few days the measurement of air activity was of foremost importance both in order to see how the situation was developing and to estimate initial doses from the cloud direct and inhalation dose The National Defence Research Institute provided data from their ground-level stations and from daily 4 sampling flights at altitudes between 100 and 800 m The filters were analyzed for nuclide composition The dominant radionuclide in the cloud was I-131 In the Stockholm area a maximum particulate I-131 3 concentration in air of 11 Bq m was measured The maximum total 3 iodine concentration was probably around 50 Bq m Autoradiography of the filters showed hot particles dominated by radionuclides such as molybdenium cerium ruthenium and zirconium Figs 2 and 3 shows the variation of I-131 and Cs-137 in Stockholm and at Ljungbyhed in southern Sweden during the first two weeks A Pu-239 240 Cs137 activity ratio obtained from measurements on rainwater and filters made by Forsmark and FOA was of the order of -4 10 The outdoor radiation level was continuously followed by the gammamonitoringstations The highest increase in this system a factor of ten was registreted at Umeaa in the northern Sweden Some other stations gave no detectable increase at all An exemple of the variation of the outdoor radiation level is given in Fig 4 The highest initial increase of the outdoor radiation level in the country was a factor of approximately 100 measured in the Gavle area An over-all picture of the ground deposition in all of Sweden was obtained by aerival scanning from a height of 150 m The scanning operation which was carried out by the SGAB revealed a considerable variation in ground activity due to local rain during the cloud passage Fig 5 shows the exposure rate calculated from aerival scanning By combining the aerial scanning result with the in-situ measurements it was also possible to calculate the distribution of some dominant radionuclides on the ground An example of such a distribution is depicted in Fig 6 The high-concentration areas were also surveyed by road vehicles As can be seen from Figs 5 and 6 the highest deposition was found around the towns of Gavle and Sundsvall where the ground activity of 2 2 Cs-137 exceeded 85 kBq m with local levels reaching 200 kBq m The maximum cesium concentrations are more than 100 times the average cumulative level from all past weapons tests The far north of Sweden was only very slightly contaminated Using their mobile germanium detector system FOA made radionuclide specific deposition measurements in-situ at close to 100 places around the country These and other measurements showed that the short-lived radionuclides were generally dominated by I-131 and the long-lived by Cs-137 The initial April 30 I-131 Cs-137 ratios were typically around 5 A strong variation in the ratio of short-lived Te-132 to I-131 was observed In the wet-deposition areas the 5 initial tellurium activity was of the same order of magnitude as I-131 the ratio being up to 15 times higher than in the dry-deposition areas This meant that the activity in the highintensity regions initially decayed somewhat faster than in the lowintensity regions After six weeks the ground activity was dominated by Cs-137 and Cs-134 with the ratio 1 0 6 In parallel with the large-scale surveys a large number of detailed measurements were carried out by many organizations throughout the country mainly of total gamma dose rates 1 m above ground An example of the radionuclide composition on an air filer in the Stockholm area is given in Table 1 Foodstuffs Very early in the emergency the SSI decided on action levels in terms of the expected dose equivalent As a result attention was focussed on the food chain grass-cow-milk The maximum acceptable 2 ground deposition for I-131 was initially taken to be 10 kBq m 2 assumed to correspond to 3 kBq m of grass and 2 kBq 1 of milk For 2 2 total cesium the corresponding figures are 3 kBq m 1 kBq m and 0 3 kBq 1 respectively There is considerable uncertainty in the conversion from ground to grass activity the ratio varying with the conditions at the time of the fall - out In most parts of the country the ratio of grass-to - ground activity turned out to be less than indicated above An extensive mapping of grass deposition by means of grass sample measurements was therefore given high priority starting from the south where the outdoor grazing season had just begun here the limits were exceeded milk-cows were kept in their cow-sheds In the southern parts of the country the measured values mostly lay below the limits or fell below them within t he first few weeks The SSI has been monitoring radionuclides in dairy milk since 1962 The sampling program was extended successively during the first few days of the emergency and after May 2 covered all 42 commercial dairies of the country Because of the grazing restrictions imposed initially the iodine concentrations in dairy milk stayed well below the limit of 2 kBq 1 even where the ground deposition was high High measured values were around 0 2 kBq 1 In a single sample from a farm a I-131 concentration of 2 9 kBq l has been measured An example is given in in Fig 7 Attention is now concentrated on the regions with high cesium activity In the limited areas where the grass activity might still warrant restrictions the measured milk concentration is now the direct indicator for possible countermeasures A number of farms have been selected for long-term detailed monitoring Direct milk 6 measurements have generally given more favourable results than were predicted from ground and grass activity In general cesium concentrations in dairy milk have increased when the cows were let out for out-door grazing but have stabilized at a low level as can be seen from Fig 8 The ratio Sr-90 Cs-137 in different samples is of the order of 1 per cent In some milk samples however with low activity concentrations the measured ratio have been higher This is caused by the Sr-90 background from the atmospheric nuclear weapons tests in the 1960s The activity in drinking water from municipal water supplies and private wells is now lower than 0 01 kBq 1 In May some wells vere temporarily contaminated by surface water during the snow-thaw period resulting in higher concentrations As for other foodstuffs products that might have been affected have not yet been ready for the market to any appreciable extent An extensive long-term monitoring program is being carried out by the National Food Administration SLV in collaboration with SS This comprises both tests of the various foodstuffs and so-called food basket investigations In principle the same action level is applied to all foodstuffs as to milk i e 0 3 kBq Cs-137 per kg or litre Meat from domestic animals having grazed in the more contaminated areas has generally s hown concentrations well below the limit However in some instances cesium values near the limit have been observed for beef which has led to more detailed control in the pertinent regions In sheep the problem may be more pronounced due to different grazing habits The meat from several adult animals has had to be discarded after slaughter because the limiting value has exceeded by at most a factor 4 A slight degradation of the s ituation may be expected later in the season as grazing takes place closer to the ground and young animals feed more extensively on grass For game the limiting value i s clearly exceeded in the highly contaminated regions So far samples hav e been obtained mainly from animals killed by traffic Although the mean i s below the limit the following peak values have been repor ted for hare around 5 kBq kg venison 8 kBq kg woodcock 16 kBq kg and moose 1 kBq kg The situation will be closely monitored No meat with an activity concentration exceeding 0 3 kBq kg will be marketed In accordance with a recent decision by the National Environmental Protection Agency individual high values do not justify general restrictions for the hunting season For woodcock t hough there is a recommendation issued in June not to hunt those birds due to their high cesium concentrations 7 For fish in the sea only very low cesium concentrations have been measured Also fish in fresh water in the south and northernmost parts of Sweden have concentrations well below the limit In some other areas Cs-137 concentrations up to many kBq kg have been measured There are however large differences between different types of fish and also between different lakes even when the lakes are close together The National Food Administration has an extensive measuring program in progress For vegetable foodstuffs values above the permissible level have been obtained in the more highly contaminated areas primarily for early species that were well developed at the time of the fall-out such as chives parsley and nettles at most 3-4 kBq kg For later species such as rhubarb lettuce berries and potatoes no alarming values have so far been reported but the situation will be closely watched throughout the growing season The most pronounced long-term problem seems to arise in connection with reindeer breeding which is the main livelihood of the Lapps Already after the weapon fall-out in the 1960s it was found that the cesium uptake is exceptionally high in reindeer mostly due to their uniform diet of reindeer lichen Reindeer killed in the highly contaminated regions after the accident s how cesium concentrations at or above the permissible in a large fraction of the cases more than 10 kBq kg The levels cannot be counted on to decrease to levels below 0 3 kBq kg over the coming years in the highest contaminated areas without special countermeasures As may be expected from the general activity situation no alarming concentrations have been found in humans The values in mothers' milk have been very low - below 0 025 kBq 1 of I-131 The measurements were carried out sho rtly after the cloud passage Some whole-body measurements are in progress 4 Countermeasures and their effects In an accident situation the existing limits for permissible releases cannot automatically be applied The ALARA philosophy must be the guiding principle i e the radiation doses should be kept as low as is reasonably achievable with due consideration to economic and social costs In the face of the Chernobyl fall-out situation there was no firm basis for detailed considerations of a formal nature In other words neither available information nor time permitted cos t-benefit or similar analyses at the level of scientific sophistication attempted under normal circumstances Instead common sense and rule of thumb analyses supplemented by very coarse cost-benefit considerations had to be used It is interesting to note that both the types of 8 countermeasures and the action levels decided on in various countries still agree reasonably well One of the first questions was whether to recommend intake of inactive iodine At no time was this considered necessary In spite of repeated statements that there was no reason to take iodine pills drugstores reported increased sales of such pills Very few countermeasures were regarded as necessary or feasible against radiation from the cloud or from ground depositions Thus no recommendations against outdoor activities were issued even for pregnant women or children However opinions expressed by independent researchers e g that children should not play in sand pits were publicized A few cases of industrial hygiene problems were dealt with One was connec t ed with the replacement of air filters in use in large buildings such as hospitals during the cloud passage Personnel were advised to wear breathing masks and protective gloves when handling the filters Recommendations were also given for travellers People were advised not to go closer to Chernobyl than 100 km and to go within 500 km of the site only after personal consideration of the purpose of the trip Intake of food and beverages is the route where countermeasures are easiest to apply and most effective and this is the area where the most extensive recommendations were given It was judged at an early stage that the normal dose limits to the public ought not to be exceeded through the intake of contaminated food This then meant that the annual intake dose should not exceed 5 mSv for the next couple of years and 1 mSv on a long-term basis These limitations should apply to the most exposed group young children Fulfilment of the former condition would probably imply fulfilment of the latter The following rounded-off conversion factors were used between equivalent whole-body dose to a 1- year-old and acti vity intake -7 I-131 2 X 10 Sv Bq -7 Cs- 137 Cs - 134 10 Sv Bq For cesium then an annual dose of 5 mSv would correspond to a daily intake of 137 Bq Assuming an intake of some 0 3 kg per day for a 1year-old and rounding off gave the activity limit of 0 3 kBq of Cs137 per kilogram litre quoted above For iodine the activity concentrations in milk and other foodstuff could be foreseen to diminish rapidly An acti vity limit of 2 kBq kg or per 1 established in earlier recommendations was therefore accepted 9 No other radionuclides were expected to make major contributions to the dose In order to observe the above limits a number of countermeasures were decided upon It was recommended that cows should not be allowed to graze out-of-doors until a region was cleared on the basis of grass sample measurements hile grazing restrictions were in force in a region people were recommended to refrain from eating green vegetables such as parsley chives dandelions and nettles as well as morels Recommendations were also issued against drinking rainwater Since the grazing season had not yet or just barely started at the time of the accident the losses incurred by the farmers in most parts of the country were limited In the most heavily contaminated regions however where clearance could take many weeks the last region was declared free for grazing on June 25 there were difficulties in procuring hay for stalled cattle and the productivity of the cows decreased In a few cases grass had to be mown and discarded Special harvesting methods were developed leaving a higher stub than usual to avoid contamination with radioactive soil The use of sewage sludge for soil improvement is common in Swedish agriculture Since rain-water from large areas is drained to the sewers activity concentrations in the sludge in some cases rose to levels that made it unacceptable for the purpose The limits have been set at 4 kBq kg wet weight and 20 kBq kg dry weight At an early stage the Government declared that compensation would be paid for costs incurred because of the accident The total costs have not yet been established The further aim of reducing the radiation doses from intake of food will be subject to the results of the continuing monitoring program Since high cesium concentrations have been observed in some freshwater fish and fishing is a highly decentralized activity the National Food Administration has issued a statement that it is not advisable to eat fish from 14 communities in the highest contaminated area In some other communities fish should not be eaten more than once a week The most severe long-term problem is foreseen in connection with reindeer breeding in the most contaminated counties The problem will not become acute until the slaughter season in the fall and thus no formal recommendation is given yet However it seems likely that a sizeable number of animals will have to be discharged One of the major economic detriments experienced in Sweden because of the accident has been the decline in foreign tourism to Sweden Greatly exaggerated reports of the radiation levels in Sweden have been published in various countries 10 5 Estimated radiation doses The estimated total doses are still tentative Doses received during the passage of the cloud either from direct radiation or from inhalation have been negligible Rather the doses are almost entirely due to ground deposition The dominating factor is the direct ground radiation dose from cesium Food intake doses although not yet calculable with great accuracy are expected to contribute of the order of a few tenths of a mSv in 1986 Investigations have been started to estimate the activity in a typical Swedish diet in order to obtain a better foundation for dose calculations For the regions of highest contamination initial ground dose rate 0 01 mSv per hour the total equivalent whole-body dose for the whole of 1986 is calculated to be 4 mSv assuming 8 hours a day outof-doors and a population living in small wooden houses that offer little protection For 2 hours a day out-of-doors and an apartment house the corresponding dose is 1 1 mSv About 75% of the 1986 dose will be received after June 1 The collective effective dose commitment for all years to come to Swedes is estimated to be about 10 000 manSv Of course this figure is only a rough estimate 6 Information to the public It soon became clear that the attitude of the general public to the emergency would be a grave problem One of the main causes of the problem is the general unfamiliarity with radiation and radiological risks A lesson which has been learnt therefore is that the issuing of information to the public must be improved in this respect The policy of the SS and other authorities has been complete openness in providing information as it became available This did not always improve the credibility of the SSI and other authorities The following circumstances aggravated the situation - Initial estimates of radiation levels doses and risks had to be revised as more data became available - The organizations involved in data collection reported not only different quantities activity dose rate etc but also used different units rem rad gray sievert becquerel etc giving apparent inconsistencies in numerical values and creating confusion 11 - Assurance that the individual risk even in highcontamination areas was negligible appeared to be in contradiction with the stipulated countermeasures -Critics of generally accepted radiobiological risk factors received relatively great publicity questioning the recommendations and estimates of the consequencies issued by SS The normal SSI facilities and staff were found to be inadequate for the occasion Telephone calls from worried or frightened individuals blocked the switchboards As many as 2 000 calls a day were received Many more did not get through The questions ranged from the advisability of making trips abroad to possible radiological explanations to sudden illnesses Another lesson learnt therefore is that competence to give authoritative information must be decentralized to a higher degree Several research projects on public perception and how it was influenced during the emergency have been initiated 7 Responsibilities of different authorities and organizations Under normal circumstances SSI supervises the use of radiation and issues licences etcetera in accordance with the law on radiation protection Early consultations made it clear that the Government agreed with SSI that dramatic action such as evacuation of large groups of people which would have meant invoking the law on atomic defence were not called for The most important role for SSI was therefore to coordinate activities and give advice and recommendations In some cases formal decisions rested with SSI in other cases other government bodies took decisions based on SS recommendations The National Defence Research Institute FOA supports SSI with measurements and calculations Other organizations involved in sampling and measurement are hospitals and universities power plants research institutes and the Swedish Geological Co SGAB who supplied a whole series of maps with isolives for doserates based on aerial measurements The National Food Administration SLV establishes formal limits for the radioactivity in food after consultation with SS They also design and run control programs for foodstuffs The Board of Agriculture LBS issues recommendations to farmers reindeer owners etcetera on how to minimize the effects of the Chernobyl accident They are also responsible for disbursement of compensations and damages In these activities they use their field organization comprising a number of local agricultural panels 12 The Board of Occupational Safety ASS issues recommendations on industrial hygiene for instance as to the need or lack of need for protective clothing The Environmental Protection Board SNV issues licences for instance when sludge must be deposited and is also responsible for exceptional changes from the game hunting seasons The Nuclear Power Inspetorate SKI - which would have extensive duties in a domestic accident - has given advice on the likely evolution at the accident site The Board of Health and Welfare SoS is eo-responsible for the supply of inactive iodine and has provided information for medical staff The Swedish Meteorological and Hydrological Institute SMHI supplies and interprets necessary weather data The county councils are equipped with nature conservancy units and county veterinarians and give advice to local municipal authorities The latter have in varying degree taken part in sampling and in some cases measurements Many other public and private organizations have also been involved At the practical level the Board of Civil Defence SRV have provided very important assistance in the shape of extra staff for basic functions at SSI The full Swedish names and addresses of these authorities are given in Appendix 1 13 Appendix 1 Names in English and vedish mailing addresses and telephone numbers of some of the organizations involved in actions and countermeasures after the Chernobyl accident National Institute of Radiation Protection NIRP Statens stralskyddsinstitut SSI Box 60204 SWeden 46 8 24 40 80 S-104 01 STOCKHOLM National Defence Research Institute Dept 215 Forsvarets forskningsanstalt avd 215 FOA 215 Box 27322 S-102 54 STOCKHOLM SWeden 46 8 63 15 00 Swedish Geological Company Sveriges geologiska aktiebolag SGAB Kornhamnstorg 53 S-111 27 STOCKHOLM SWeden 46 8 14 42 20 National Food Administration Statens livsmedelsverk SLV Box 622 S-751 26 UPPSALA veden 46 18 17 55 00 National Board of Agriculture Lantbruksstyrelsen LBS S-551 83 JONKOPING veden 46 36 16 94 20 National Board of Occupational Safety and Health Arbetarskyddsstyrelsen ASS S-1 7l 84 SOLNA SWeden 46 8 730 90 00 National Environmental Protection Board Statens naturvardsverk SNV Box 1302 Sweden 46 8 799 10 00 S-171 25 SOLNA Nuclear Power Inspectorate Statens karnkraftinspektion SKI Box 27106 S-102 52 STOCKHOLM SWeden 46 8 63 55 60 National Board of Health and Welfare Social styrelsen SoS S-106 30 STOCKHOLM veden 46 8 783 30 00 vedish Meteorological and Hydrological Institute Statens meteorologiska och hydrologiska institut SMHI S-601 76 NORRKOPING veden 46 11 15 80 00 National Board of Civil Defence Rescue and Fire Service Statens raddningsverk SRV Karolinen S-651 80 KARLSTAD 46 54 10 30 00 All addresses above are complete i e the zip code is sometimes the ful l address In the phone numbers 46 is the country code for veden i e numbers become complete when the routing number for international calls i s subs tit uted for in the numbers 14 Table 1 Radionuclide composition as measured on an air filter from Grindsjon Stockholm Sampled 13 25 April 28 - 10 00 April 30 FOA Nuclide Cs-137 I-131 Te-132 Cs-134 Ba- 140 Np- 239 T1 -129m Ru-103 Mo-99 Cs-136 Nb-95 Activity relative to Cs-137 1 0 2 9 2 3 0 49 0 47 0 40 0 32 0 30 0 18 0 17 0 16 Nuclide Zr-95 Ce-141 Ce-144 Ru- 106 Pu-241 Cm- 242 Pu- 239 Pu-240 Am-241 Pu- 238 Cm-244 Activity relative to Cs-137 0 13 0 13 0 076 0 056 0 015 0 0016 0 00022 0 00016 0 00014 0 00010 0 000016 Note Due to sampling techniques t he I-131 concentrat ion is underestimated by a factor of approximately 5 Fig 15 o Location of SSis National Institute of Radiation Protection permanent 25 gammastations o o Kiruna Location of FOAs Defence Research Institute permanent 7 air-samples stations e Tj motis tlvertornea eHemavAn '' ' A lvsbyn o ' r' ' o Ulvoberg I I ' II Tang 1 ' '- _ _ ' oo Jl Froson ' Ume Air activities of 1-131 at Stockholm and Ljungbyhed 10 2 10 -- 1 Stockholm o Lj ung byh ed 10 I ' E - '- 1 o- 1 o- OJ 1 o- 2 1 o-J 10 - 30 I A 6 8 10 12 14 16 18 20 22 24 FOA215 NUCLEAR DETECnDN '1J I Q N Air activities of Cs-137 at Stockho lm and Ljungbyhed 1o -- Stockholm o Ljungbyhed 10 1 o-l I E - '- _ o- - J l 1 o- 2 1 o-J 10 28 3 0 -- -- -L--l- -- 2 4 6 8 10 12 14 16 18 20 22 24 4 MAY FOA215 NUCLEAR DETfCTlON 1-rj I Q w National Institute of Radiation Pro tection Stockholm Sweden FGUR-MONTH GAMMA LEVELS FOR STATION UMEAA 1986 -------- 1000 1000 r-J- 1100 x 1- 1100 0 t ll IJ l c 100 1-- 100 f- 71 0 700 I- 1-1- eco eoo f- 1- eco lOO X l z z XX 400 c 3CO 300 r- 2IXI 200 100 100 0 APRIL JUNE MAY JULY Doserate in a i r ktrmarate at SSis permanent registering gamma station in Umea The sta tion me asure at 2 5 m he igth above gro und l eve l IT CXl t-' 0 t- CONTAMINATION MAP Estimated ground intensity on May 9 1986 in j lR h The map is based on aerial surveys from May 9 to June 3 1986 - -300 -200 -100 50 20 10 5 Cl 0 100 200km I 'j SVERIGES GEOLOGISKA AB 0 Ul OJ CONTAMINATION MAP Estimated ground intensity on May 9 1986 in The map is based on aerial surveys from May9 to June 3 1986 -300 -200 - - - ' - i - - r - J -- d ' -- STOCKHOLM - _- ' - _ - N _ ilo _ ' - 0 -100 - so - 20 - 10 - 5 I 0 100 200km -- o 0 lJl tJ' SVERIGES GEOLOGISKA AB r -- J ' cEsrur 137 kBq m ground surface Preliminary results based on aerial surveys from May 1 Z - 7 1986 -120 kBqjm - 85 r- 2 - 50 30 N 15 11 9 7 5 3 0 100 200 km I SVERIGES GEOLOGISKA AB J 0'1 ll CES 137 kBq m ground surface Preliminary results based on aerial surveys from May 1 - Z 3 1986 -120 kBqjm 2 - 85 50 30 15 11 9 7 5 3 N N 0 100 200 ltm SVERIGES GEOLOGISKAAB - j Q 0 tJ ' Dairy milk activities of 1-131 at Uppsala and Govle 60 -- -- -- -- -- -- -- -- -- 50 1- Uppsala it o Gavle 40 'd CD I rl I IIlL I I I 111111 xf I - _ l - 't N w 30 20 10 0 25 MAY JUNE ' ' I Q -- J Dairy milk activities of Cs-137 at Uppsala and Gavle 60 -- -- -- -- -- -- -- -- -- Uppsala 50 o Gavle 40 '- _ CJ 30 CD 20 10 0 I 25 5 15 JUNE 25 5 15 25 JULY N ' f-' 1 0 CO HITTILLS UTGIVNA SSI - rapport 1986 Rapportnummer Titel undertitel F'orfattare 01 Limitation schemes to decrease the radon daughters in indoor air Gun Astri Swedjemark 02 Radondottrar och bildskarmsarbete Resultat av en forstudie Rolf Fa lk Leif Nyblom 03 Cesium-137 och strontium- 90 i mejerimjolk Arsrapport for 1985 Miljolaboratoriet 04 Isotopkommitterapporter 1984 Gunilla Hellstrom Ingemar Malmstrom 05 Det falska larmet vid Forsmark den 6 mars 1986 Orjan 06 Cesium-137 i strals dsinstitutets kontrollgrupp 1985 Gunnar Eklund Rolf Falk 07 Nedfall fran Tjernobyl Preliminar rapport Per-Einar Kjelle 08 Nordisk jamforelsematning av radioaktivitet i byggnadsmaterial Hans More 09 Karnkr a ftindu s trins -aktivitetsutslapp -yrkesexponeringar Fjarde kvartalet 1985 Huvudenhet f or karnenergi 10 Tjernobyl nedfall matningar och konsekvenser Torkel Bennerstedt Mats Holmberg Lennart Lindborg 11 Persondosmatningar Arsrapport 1985 Albert Kiibus 12 Chernobyl - its impact on Sweden Hultaker SS Staotens This document is from the holdings of The National Security Archive Suite 701 Gelman Library The George Washington University 2130 H Street NW Washington D C 20037 Phone 202 994-7000 Fax 202 994-7005 nsarchiv@gwu edu