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National Atomic Energy Agency, Warszawa, Poland

Abstract

The paper presents a schematic outline of the radiation emergency policy in Poland, rather from the point of view of logistics of the problem than discussing details of existing or proposed procedures.

1. INTRODUCTION

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There are no power plants in Poland; the Polish nuclear power programme was interrupted in 1990 when the Polish Parliament decided that construction of the nuclear power plant in Zamowiec (two WWER-440/213 units had been constructed since 1982, two other were planned) was not to be continued. However, nonexistence of nuclear power plants or nuclear fuel processing installations on Polish territory does not mean that radiation emergency situation cannot occur in Poland and that radiation emergency planning is not needed.

According to the Atomic Energy Act [1], the National Atomic Energy Agency (NAEA), being a governmental nuclear regulatory body in Poland, is responsible not only for licensing and inspection of all the activities involving atomic energy (including application of radiation sources in industry, medicine and R&D), but also for radiological protection of the whole population. Therefore, a proper planning and execution of intervention procedures needed in case of radiation emergency situation, based on monitoring system, early warning information network and decision supporting programmes, play a most important role in the NAEA legislative and executory activities.

2. POTENTIAL SOURCES OF RADIATION EMERGENCY

Radiation emergency in Polish reality may be caused by the incidents in:

-nuclear (research) installations in Poland or nuclear installations in neighbouring countries;

-radioisotope laboratories and radiowaste management system;

- transportation of radioactive materials within the country and declared or undeclared (illegal) trans-border transportation.

Polish nuclear installations consist of two research reactors, 10 and 30 MWth of power, and of a spent fuel interim storage facility containing about 5000 spent fuel elements (of about 2x1016 Bq activity), all located in a research centre at Swierk, 20 km from Warsaw.

There are about 2750 isotope laboratories in research institutions, hospitals and clinics and in industry; 30 laboratories use radioisotopes in field works. More than 420 utilise open, unsealed sources (445 of the lowest, 60 of the medium, and 15 of the highest category/class, and more than 15 in the field). Radioisotopes of different kind and for various purposes (mainly radiopharmaceuticals) are offered by 15 producers through more than 70 dealers. The biggest manufacturer of radioisotopes in Poland is OBRI (R&D Centre of Isotopes) at Swierk which in 1993 produced and sold 4000 sealed sources and 82000 portions of unsealed radioactive material (2xl015 Bq and 5xl013 Bq, respectively). This list of users of radioactive materials does not include all the applications of radioisotope (Pu or Am) smokedetectors (about l m In detectors in more than 6000 institutions). [2]

Polish radioactive waste immobilization and deposition system consists of the waste treatment installation at Swierk and the landfill low and medium activity waste (RMI type) repository at Rozan (100 km from Warsaw); annual amount of wastes processed and finally stored being about 175 m3 of liquids and about 100 m3 of solids, the total activity deposited in 1993 was about 1014 . [2]

Within the range of 200 km of a Polish border there are 7 nuclear power plants with

17 active units of total installed capacity of 14 GW(e). If the 600 km range is

considered, the total number of nuclear power plants is 26 (50 reactor units), including the Chemobyl-type RBMK reactors and the oldest versions of WWER reactors.

Potentially all the mentioned above installations and radioisotope users can create an emergency situation and can cause a need for intervention. Signals in such situations may come to the decision making centre directly from the user (or from a special service operating at the site, e.g. pohce, fire brigades etc.), through special monitoring stations (contamination measuring units) or from the exchange-of-information contact point (due to the international and bilateral obligations and agreements signed in Poland).

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3. RADIATION MONITORING

The radiation monitoring system as considered from the point of view of emergency planning is now under reconstruction Generally, if has to consist of two subsystems

-a core subsystem, depending (administratively and financially) entirely on the National Atomic Energy Agency (NAEA), containing about 10 field stations spread throughout Poland,

-auxiliary system, i c other stations belonging to other Polish institutions (under ministries of health, of environmental protection, of defence etc ), providing data for the purposes of early notification on emergency situations, if those data correspond to the requirements and standards set up by the NAEA

The radiation monitoring system can operate at four différent levels of activity, depending on the degree of emergency situation These levels can be defined as -normal (all readings correspond to the background within the agreed level of discrepancies),

-elevated (there exists a possibility of an increase of the radioactive contamination due to the accident reported to the centre),

-emergency (the reading exceeds significantly an agreed background le\el or there are confirmed in reports on the accident which may create the emergency situation), -post-emergency (during the period of time between the occurred emergency situation and the return to the normal = background level readings)

The measurements performed by field station consist of the following elements -gamma-ray dose (in air),

-radioactivity of precipitation,

-radioactivity contamination of suspended air particulates,

-radioactivity of other environmental samples (soil, water, plants, foodstuff and feedingstufï),

including spectrometry, if identification of radionuclides is needed Different levels of the measuring system generally mean the differences in timing regime of the measurements or of reporting on the results [3, 4, 5]

4. DATA ANALYSIS AND INTERVENTION

All the information coming from the radiological monitoring system (in real time or as the post-measurement reports, eg on the mean value of air contamination by

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