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This article assesses the radiological environment at the nuclear site of the Mayak PA, Russian Federation, during and after the accident in 1957, the so-called 'Kyshtym Accident', and the radiation doses to those who participated in the eradication of its consequences. Based on numerous archival documents, this paper presents the radiation data for 1957-1960, including individual dosimetry monitoring data and estimated doses to the Mayak workers, as well as the to personnel in supporting organisations and the military involved in the remediation operations. From 1957-1959 some 38 500 individuals took part in the clean-up actions and remediation of contaminated areas of the Mayak PA industrial site after the accident, including individuals exposed at the time of the accident: Mayak PA employees, militarypersonnel, and civil construction workers. External equivalent doses to 10 500 individuals were estimated in the range of 220 to 265 mSv, while there were cases of doses up to 950 mSv and higher. The collective dose received during the accident and its aftermath was in the region of 7300 person-Sv. By October-December 1957, the collective dose was about 4500 person-Sv. Collective doses recorded in 1958 and 1959 amounted to 2250 person-Sv and 480 person-Sv, respectively.

Nuclear sites around the world are being decommissioned and remedial actions are being undertaken to enable the sites or parts of the sites to be reused. Although this is relatively straightforward for most sites, experience has suggested that preventative action is needed to minimise the impact of remediation activities on the environment and the potential burden to future generations. Removing all contamination in order to make a site suitable for any use generates waste and has associated environmental, social and economic detriments and benefits that should be taken into account. Recent experience of OECD Nuclear Energy Agency (NEA) member countries in the remediation of contaminated land, predominantly contaminated soil and groundwater, on nuclear sites during decommissioning has been assessed by an NEA task group. The experience was used to identify strategic considerations for nuclear site remediation, to consider the application of sustainability principles to nuclear site remediation, to describe good practice, and to make recommendations for further research and development. The key aspects that were identified were that 1) site remediation should be sustainable by resulting in an overall net benefit; and 2) an adaptive approach is essential in order to take into account the inherent uncertainty associated with the decommissioning and site remediation timescales. A report describing the findings was published by OECD/NEA in 2016. The conclusions provide insights to decision makers, regulators, implementers and stakeholders involved in nuclear site decommissioning so that they can achieve sustainable remediation of nuclear sites, now and in the future.

The potential consequences for Norway should a nuclear accident at the Sellafield nuclear site occur, have been of concern for Norwegian authorities for several decades. Meteorological data from a 33-year period and the dispersion model ‘SNAP’ were used to evaluate meteorological conditions for which atmospheric transport of radionuclides from Sellafield to Norway would lead to the most severe impacts. The worst-case meteorological scenario for Norway, was found on 25th June 1989 for a low elevation (0–800 m) release and on 29th June 2001 for a higher elevation (800–1600 m) release. In both cases the western part of Norway was most affected. In general, the probability for depositions (>10 Bq/m2 of 137Cs) increased about 40% during the autumn and winter compared to the spring and summer months. An influence of climate change on the depositions was analysed, but not verified. Results from a number of simulations were also compared to identify how factors such as radioactive particle characteristics and initial release conditions could affect the predicted radionuclide deposition. The impact on predicted total depositions as well as hot-spot depositions by varying particle density and size as well as release elevation in worst-case scenario simulations amounted to about 40%–50%.

No commercially available detector system can measure alpha, beta and gamma-rays at the same time and separately with good efficiency, while being cost-effective, portable and offering real-time monitoring. The main purpose of an alpha-beta-gamma detector would be for safety management and nuclear decommissioning in the nuclear industry. This idea for a detector system became more valuable, after Fukushima in Japan, because nuclear waste can contain fission products and transactinide materials which not only emit gamma-rays but also emit alpha and beta particles and in some cases, neutrons. In this research, we investigated the best available alpha-beta-gamma radiation detector materials and their optimum thickness by using Geant4 based GATE simulation. The work revealed a better efficiency result for each radiation type than in previous work. In the simulation, 0.05 mm ZnS(Ag), 3.2 mm plastic scintillator and 1.75 mm BGO were found to be best for the detection and identification of alpha, beta and gamma-rays respectively. In nuclear medicine, this type of detector system could also modify to become a miniaturized radio-guided surgery beta-gamma probe beside of the modification into the robotic surgery. This research result will influence three different areas in imaging technology, homeland security and nuclear industry.

The potential for adverse health effects from internal exposure to Plutonium has been recognised since its discovery in the 1940s. However, in the absence of specific information, potential risks from Plutonium exposure have always largely been controlled through knowledge of radiation exposure risks in general, much of which comes from external radiation exposures. To try to obtain more direct estimates of potential internal exposure risks, epidemiological studies of Plutonium workers need to be conducted. Such epidemiological analyses require individual Plutonium exposure estimates that are as accurate and unbiased as possible. The UK Sellafield workforce includes one of the world’s largest cohorts of Plutonium workers, which constitutes, by some considerable margin, the group of workers most comprehensively monitored for internal exposure to this alpha-particle-emitter. However, for several hundred workers employed at the start of Plutonium work at the facility, during the period from 1952 through to 1963, the historical urinalysis results available cannot provide sufficiently accurate and unbiased exposure assessments needed for use in epidemiological studies. Consequently, these early workers have had to be excluded from epidemiological analyses and this has significantly reduced the power of these studies. A promising quantitative methodology to overcome the issue of missing or deficient exposure data, is to use exposure data from other sources to estimate the average exposure a ‘typical worker’ would have received, and to collate this information for specific occupations and years. This approach is called a Job-Exposure Matrix (JEM). Work on a pilot study to construct a population-specific quantitative JEM for the early Plutonium workers at Sellafield during 1952–1963, for whom reliable urinalysis results do not exist, has shown the potential for a JEM approach to produce more reliable and useful exposure estimates for epidemiological research.

During the last 15 y, by the Saluggia (Vercelli, Italy) nuclear site, episodes of contamination of the superficial groundwater happened due to artificial radionuclides. The local network of radiological monitoring around the nuclear site, managed by Arpa Piemonte from the late 1980s, highlighted the presence of (60)Co, (90)Sr, (137)Cs and (3)H during this period. The object of this paper was to give particular evidence not to analytical aspects, but to the methodical approach used to solve the problems that arose. In fact, the intrinsic hydro-geological vulnerability of the zone, the typology and conditions of the plants (all very old) and the presence of the 'Acquedotto del Monferrato' tap water well field, one of the most important in Piemonte, at approximately 2 km downstream of the site, made the situation very difficult to approach.

The University of Washington Burn Center opened in 1974. At that time, 18 facilities provided burn care in Washington, Alaska, Montana and Idaho. Today, the UW Regional Burn Center cares for most of the critically injured burn patients in the four states (patients in south-eastern Idaho and Montana are routinely referred to the Intermountain Burn Center in Salt Lake City). The UW Burn Center is located at Harborview Medical Center (HMC), a county owned hospital that is operated by the University of Washington. Also located at HMC is the Level 1 adult and pediatric Trauma Center that cares of patients from Washington, Alaska, Montana and Idaho. Within the Pacific Northwest region served by HMC, continuous risk for potential burn disasters include both industrial and natural hazards. Seattle is a major deepwater west coast seaport and the International SeaTac Airport handles worldwide cargo. Three Boeing airfields and two airplane plants increase the risk of a major aircraft disaster. Interstate route 5 running North–South and Interstate route 90 running East–West are used routinely to transport hazardous materials from these entry ports to other regions in the USA. Alaskan pipelines run from the Canadian border through this region to refineries in northern Washington. Whereas, logging and paper mills are less ubiquitous than they once were, pulp mills with their huge vats of alkali liquor constitute a potential risk of major chemical burns. In eastern Washington, the Department of Energy Hanford Nuclear site, once serving as one of three engineering sites for the Manhattan Project (1943–1946) and now as nuclear storage poses a potential radioactive disaster for the Pacific Northwest region. In addition, the state of Washington claims four active volcanoes and Seattle sits on eight recognized seismic faults. Each of these man-made and natural entities

Exposure to radon and its daughters is one of the important contributions for radiation doses to the publics. In this study, concentrations of radon gas were measured in air at Al-Tuwaitha Nuclear Site and some surrounding areas. Measurements were achieved by RAD7 (radon detector), manufactured by DURRIDGE COMPANY Inc. Indoor radon concentration plays a vital role in the total effective dose in the indoor environments. The measurement of the indoor radon concentrations ranged from (4.96±4.4 to 102±25) Bq/m 3 this high value of radon has been found at Decommissioning Directorate /emergency room, which is lower than the action value recommended by the EPA (Environmental Protection Agency) which is (148 Bq/m 3 ) while the lowest value has been founded in the Central Laboratories Directorate \ models Room. These values were used to calculate the annual effective dose, the dose exposed to the soft tissues other than the lungs D soft tissue , the dose rate due to alpha-radiation D lung and the effective dose equivalent rate H eff . The values of the annual effective doses for 222 Rn inhalation by the people were calculated and ranged from (0.124992 to 2.5704) mSv/y these result are lower than the value of (10 mSv/y) recommended by the ICRP (International Commission on Radiological Protection). It has been observed that winter concentration of indoor radon are greater than summer concentrations. The higher amount in the winter is attributed to the observation that people normally keep their windows closed during the winter, allowing indoor radon concentrations to rise. The lower radon concentrations in the summer might occur because people often open their windows, allowing low-radon outside air to enter the home. The results from this study show that the region has background radioactivity levels within the natural limits.

In this study Soil gas radon 222Rn activity was measured in different locations at Al-Tuwaitha Nuclear Site and the surrounding areas using RAD7 (radon detector). Radon activity in the soil gas varied from (866±150 to 16004±521) Bq/m3 near Alaibtihal School and Ishtar \ Al-Ttakhi School respectively. These concentrations values are well below the allowed levels that range from (0.4 to 40) KBq/m3. The annual effective doses related to the inhalation of radon gas and its progeny which were calculated from the Concentration of emanation in air near ground ranged from (0.0082305 to 0.152102) mSv/y. these results are less than the recommended global average dose from the inhalation of radon from all sources, which is 1 mSv/y. The Health risks originating from indoor radon concentration can be attributed to natural factors and is characterized by geogenic radon potential (GRP), The highest values were found in Ishtar \ Al-Ttakhi school which is (16.004) and The lowest values were found Near Alaibtihal school which is (0.288666667), the lowest value according to Neznal was classified as low (GRP < 10) and the highest value was classified as medium (10 < GRP < 35), according to Barnet and Pacherova low GRP causes

The activity concentrations of twenty soil samples collected from contaminated locations of Fuel Fabrication Facility (FFF) at Al- Tuwaitha nuclear site, Iraq, were determined by using spectroscopy with a high purity germanium detector. The range of activity concentrations of 238U (234mPa), 235U, 232Th (228Ac), and 40K in the soil from the studied areas varies from (177.74±60) to (375777.5±6895) Bqkg-1, (7.4±0.5) to (20954±407.5) Bqkg-1, (7.06±0.22) to (20.45±0.33) Bqkg1 and from (47.5±5.3) to (402.2±15.5) Bq kg-1 respectively. The isotopic mass and activity ratio of 235U/238U were calculated to identify kind of uranium, depleted or natural. To assess the radio logical risk for this site, RESRAD program was used to calculate total dose from all pathways (external, inhalation and soil ingestion) of exposure, the value of total dose was 2mSv/yr. Laboratory results indicated that the FFF was contaminated with 234mPa and 235U nuclides in excess of the IAEA limits for exemption from regulatory control, and indicating that the decommissioning operations for the FFF must be subjected to regulatory control and safety surveillance to ensure adequate protection of the operators, public and the environment.

Children living near two nuclear sites in the United Kingdom, Sellafield and Dounreay, showed no increase in risk of leukaemia or non-Hodgkin’s lymphoma, a new analysis of cancer rates from 1991 to 2006 has shown.1 The report’s authors said that the increased incidence of these cancers found in earlier years may have been associated with exposure to infections as people from elsewhere moved into these previously isolated rural areas. The Committee on Medical Aspects of Radiation in the Environment (COMARE) has been investigating possible cancer clusters around nuclear installations for the past 30 years. A report in 1984 found an increased incidence of leukaemia in under 25s living in Seascale, a village near the Sellafield nuclear site in northwest England. A second report in 1988 found higher rates of leukaemia in children and young people living near the Dounreay nuclear site in Caithness, Scotland, compared with the …

The characteristics of atmospheric dispersion considering the building effects in the Wolsung nuclear site in Korea were studied using ISC-PRIME and ARCON96 models. The maximum 2-h average atmospheric dispersion factor (ADF) was six times larger when the building geometry was considered in ISC-PRIME and two times larger in the exclusion area boundary. Owing to different adjustments for wind speed by the stability class, the ADFs calculated using ARCON96 were smaller than those calculated using ISC-PRIME. Strategies for locating buildings need to be considered to maximise dispersion when planning for constructing several reactors and accessory buildings at the Wolsung nuclear site.

The Hanford nuclear site, built to produce plutonium for the nation's first atomic weapons, occupies 560 square miles of desert in southeastern Washington State. Only 29 months after ground was bro...

A study was carried out to determine the source rate from a nuclear power plant using the tracer experimental data conducted at the Yeoung-Kwang nuclear site. The least squares method optimises the agreement between the released source rate and the calculated source rate by minimising the errors between the measured concentrations and the calculated ones using the Gaussian plume model. The least squares estimator generally estimates the source rate to be within a factor of 2. The forecasting ability of the source rate is improved by applying the modified dispersion coefficients that are calculated using the experimental data. Determination of the source rate in an early phase nuclear emergency will be helpful for the decision making when taking appropriate and prompt countermeasures in the case of a radiological emergency.

In the ciliate Stentor, the chain macronucleus has a fixed position within the cell; it is located just beneath the region of narrow cortical striping to the right of the gullet (nuclear site). Stentor therefore lends itself well to experiments on control of nuclear positioning. I have studied this problem by microsurgically producing various abnormalities of nuclear positioning and determining how these are corrected. Breaks in the nuclear chain were repaired by segregation of broken parts into the two daughter cells at division. When a second nucleus was transplanted into a stentor, the abnormality was eventually corrected because the two parallel chains tended to move during oral development (regeneration or division) so that one was anterior to the other. The two nuclei were then segregated into the anterior and posterior daughter cells at division. When a doublet stentor, which has two nuclear sites and two macronuclei, was deprived of one nucleus, it acquired a second one because the remaining nucleus was attracted to both nuclear sites when it elongated during oral development. This phenomenon first produced doublets with a single nuclear chain sharing the two nuclear sites at opposite ends of the cell, a break in the chain then presumably created two nuclei. These latter observations indicate that one mechanism by which the nucleus is positioned involves its attraction toward the nuclear site, a differentiated region of cell cortex, during oral development. Other experiments have shown that the nuclear site also holds the nucleus firmly in place.