Assessing the value meteorological ensembles add to dispersion modelling using hypothetical releases

Atmospheric dispersion model output is frequently used to provide advice to decision makers, for example, about the likely location of volcanic ash erupted from a volcano or the location of deposits of radioactive material released during a nuclear accident. Increasingly, scientists and decision makers are requesting information on the uncertainty of these dispersion model predictions. One source of uncertainty is in the meteorology used to drive the dispersion model, and in this study ensemble meteorology from the Met Office ensemble prediction system is used to provide meteorological uncertainty to dispersion model predictions. Two hypothetical scenarios, one volcanological and one radiological, are repeated every 12 h over a period of 4 months. The scenarios are simulated using ensemble meteorology and deterministic forecast meteorology and compared to output from simulations using analysis meteorology using the Brier skill score. Adopting the practice commonly used in evaluating numerical weather prediction (NWP) models where observations are sparse or non-existent, we consider output from simulations using analysis NWP data to be truth. The results show that on average the ensemble simulations perform better than the deterministic simulations, although not all individual ensemble simulations outperform their deterministic counterpart. The results also show that greater skill scores are achieved by the ensemble simulation for later time steps rather than earlier time steps. In addition there is a greater increase in skill score over time for deposition than for air concentration. For the volcanic ash scenarios it is shown that the performance of the ensemble at one flight level can be different to that at a different flight level; e.g. a negative skill score might be obtained for FL350-550 and a positive skill score for FL200-350. This study does not take into account any source term uncertainty, but it does take the first steps towards demonstrating the value of ensemble dispersion model predictions.

Wildfires in the Atomic Age: Mitigating the Risk of Radioactive Smoke

This Perspective highlights the lingering consequences of nuclear disasters by examining the risks posed by wildfires that rerelease radioactive fallout originally deposited into the environment by accidents at nuclear power plants or testing of nuclear weapons. Such wildfires produce uncontainable, airborne, and hazardous smoke, which potentially carries radioactive material, thus becoming the specter of the original disaster. As wildfires occur more frequently with climate change and land use changes, nuclear wildfires present a pressing yet little discussed problem among wildfire management and fire scholars. The problem requires urgent attention due to the risks it poses to the health and wellbeing of wildland firefighters, land stewards, and smoke-impacted communities. This Perspective explains the problem, outlines future research directions, suggests potential solutions, and underlines the broader benefits of mitigating the risks.

Radioactive Contamination Countermeasures, Food Inspection Systems, and the Issue of Reputational Damage in the Early Stages of the Nuclear Disaster in Fukushima Prefecture

This paper overviews the achievements and challenges of radioactive contamination countermeasures, food inspection systems, and reputational damage to agricultural products in Fukushima Prefecture during the early stages of the Great East Japan Earthquake and nuclear disaster. It outlines the effectiveness of early countermeasures such as absorption control measures and soil decontamination, and observes how efforts aimed at revitalizing afflicted areas were initiated and advanced primarily through the leadership of residents and agricultural producers. Furthermore, it examines food inspection systems such as the “all-bag-all-volume” testing system for rice that was implemented in Fukushima, and suggests that a failure to extend such countermeasures to outside of Fukushima Prefecture was a contributing factor to the ongoing issue of reputational damage and consumer reluctance to purchase products from the area. Lastly, the paper categorizes early consumer trends in four groups based on differing perceptions of risk and safety, and concludes that dealing with reputational damage should entail creating maps of radioactive material distribution, and also building a rational inspection system that allows consumers to objectively identify the safety of agricultural products.

Natural Radioactivity in Soil and Bitumen in Al-Marj Spring and Abu-Jir Village, Anbar, Western Iraq

The aim of the present research is to illustrate γ-ray levels emitting from soil and bitumen producing from 238U, 232Th, and 40K along Abu-Jir Fault Zone. in the area extended from Al-Marj valley to Abu-Jir village using scintillometer device. Such study is important in environmental assessment to buildup data base about radioactivity. The concentration of natural radionuclides in the study area was determined to be occurring mostly in the clay minerals and organic matter. A high purity germanium spectrometer was used to detect the activity of these elements which ranged between 00.6±18.1- 1526±102, 0- 8.4±1.4, and 70.1±10.9- 328.2±73 in soil, and 28.2±5.6- 94±22.1, 0- 2.2±0.5, and 38.4±7.9- 70.1±10.9 in bitumen for 226Ra, 232Th, and 40K respectively. The anomaly of the Naturally occurring radioactive material was associated with hydrocarbon accumulation and springs. The source of 232Th and 40K came from the same source rock (illite), while 226Ra was associated with ascending fluids. The obtained results showed that the activity of 226Ra in soil has value above the world averages and other countries.

Karakterisasi Hidrogeologi Daerah Sekitar Tapak PLTN di Bengkayang, Kalimantan Barat

ABSTRAK. Evaluasi tapak merupakan tahap penting dalam penentuan lokasi calon tapak PLTN skala komersial di Indonesia. Aspek–aspek yang dikaji dalam evaluasi tapak berdasarkan peraturan yang berlaku antara lain aspek geoteknik dan aspek dispersi zat radioaktif. Untuk mendukung kajian aspek tersebut maka perlu adanya kajian karakterisasi hidrogeologi daerah sekitar tapak. Tujuan penelitian ini adalah menentukan karakteristik hidrogeologi daerah sekitar tapak PLTN di Kabupaten Bengkayang, Provinsi Kalimantan Barat berdasarkan aspek geologi dan geofisika. Metode yang dilakukan adalah pemetaan geomorfologi, pemetaan geologi, pemetaan hidrogeologi, pengukuran geolistrik, serta analisis terpadu. Secara morfologi, daerah penyelidikan dibagi menjadi tiga satuan, yaitu dataran aluvial, bukit terisolasi, dan dataran pantai. Secara stratigrafi, satuan batuan yang ditemukan berurutan dari tua ke muda adalah andesit, granodiorit, diorit, endapan pasir kuarsa, endapan pantai, dan endapan aluvial. Pengukuran geofisika menggunakan metode geolistrik dilakukan pada 12 lintasan dengan masing-masing panjang lintasan 470 m dan spasi elektroda 10 m. Pada penampang geolistrik ditemukan beberapa anomali pada kompleks batuan beku yang mengalami frakturasi atau tubuh diorit yang menerobos satuan andesit. Nilai anomali ini berkisar antara 300 Ωm dan >8000 Ωm. Nilai resistivitas yang sangat rendah (<30 Ωm) diinterpretasikan sebagai endapan aluvial yang jenuh air dengan ketebalan mencapai ±100 m. Daerah penelitian dapat dibagi menjadi tiga satuan hidrogeologi; akuifer dengan aliran melalui ruang antarbutir kelulusan tinggi, akuifer dengan aliran melalui ruang antarbutir kelulusan sedang, dan akuifug setempat berarti. Secara umum pola aliran tanah bebas mengalir relatif dari SSW ke NNE.ABSTRACT. Site evaluation is an important phase of site selection for commercial-scale nuclear power plants (NPP) in Indonesia. Geotechnical and radioactive material dispersion aspects are some of the aspects which are assessed in site evaluation under provisions of laws and regulations. To support those aspect evaluations, it is necessary to conduct hydrogeological characterization in the vicinity of the NPP site. The purpose of this study is to determine the hydrogeological characteristic of the vicinity of the NPP site in Bengkayang Regency, West Kalimantan Province based on geological and geophysical aspects. The methods of this study consist of geomorphological mapping, geological mapping, hydrogeological mapping, geoelectric measurement, and integrated analysis. The study area consists of three morphological units: alluvial plain, isolated hills, and coastal plain. Stratigraphically, the lithology units of the study area, from the oldest to the youngest, consist of andesite, granodiorite, diorite, quartz sand deposits, coastal deposits, and alluvial deposits. The geophysical measurement used is the geoelectric method which is conducted at 12 electrode arrays with 470 m length and spacing of 10 m. In the geoelectrical section, it can be seen that several anomalies can be interpreted as the fractured body of igneous rocks or the diorite intrusion in andesite. These anomaly values are ranged from 300 Wm to >8000 Wm. The relatively low resistivity values (<30 Wm) are interpreted as water saturated-alluvial deposits that could have a thickness of ±100 m. There are three hydrogeological units in the study area: aquifers in which flow is intergranular with high permeability, aquifers in which flow is intergranular with moderate permeability, and aquifug of local importance. Generally, the groundwater in the study area flows from SSW to NNE.

Challenges and Lessons Learnt on Waste Management and Disposal from Mauritania Deepwater Abandonment and Decommissioning Campaign

Abandonment and decommissioning activities of oil and gas assets had been on the increasing trend. As an activity of minimal to no economic value return, the investment into Abandonment and Decommissioning (A&D) should be properly strategized to ensure all objectives are met safely within available time and resources. This paper will discuss Operator's strategy in planning and handling waste from A&D activities of fifteen (15) deepwater subsea wells in Mauritania, West Africa. The approach of this A&D project at a remote location was done in two separate campaign instead of a single campaign based on technical and commercial evaluations performed by Operator. Subsea structures, Christmas trees, tubulars and others are expected to be retrieved and disposed according to local and international standard. In general, Operator are expecting two (2) type of waste which are non-hazardous waste and hazardous waste due to hydrocarbon or naturally occurring radioactive material (NORM) contamination. Due to the limitation of capable hazardous waste handling and disposal in country, Operator decided to export waste to identified facilities outside of country at the end of the project via sea-freight. Operator appointed one contractor to provide a full-service related to the waste management and disposal that covers field services and onshore services that includes radiological monitoring to identify NORM waste, labelling, packaging at offshore, onshore storage, transportation and logistics that include Trans-Frontier Shipment (TFS). The strategy of appointing one contractor for full service of waste management and disposal has promoted a single – point accountability to the contractor and this has enabled the objective been delivered effectively. COVID-19 pandemic posed a great challenge on cross-border logistic planning due to additional measure been imposed by receiving country. Furthermore, the new development of United Kingdom exiting European Union (BREXIT) also posed some level of uncertainty to the contractor to obtain relevant approvals for waste export. To reduce the amount of waste to be export, Operator continuously looking for and successfully found a local recycling facility that able to handle the non-hazardous waste while meeting local regulation, Operator's and industrial standard. All outlined strategy was proven to be effective for waste management in remote location, uncertainty on cross-border waste export challenge, as well as capitalizing on the limited local resources available.