The accident at the Fukushima Daiichi Nuclear Power Plant has raised questions about the accumulation of radionuclides in soils, the transfer in the foodchain and the possibility of continued restricted future land use. This paper summarizes what is generally understood about the application of agricultural countermeasures as a land management option to reduce the radionuclides transfer in the food chain and to facilitate the return of potentially affected soils to agricultural practices in areas impacted by a nuclear accident.

Soil is an essential component of all terrestrial ecosystems and is under increasing threat from human activity. Techniques available for removing radioactive contamination from soil and aquatic substrates are limited and often costly to implement; particularly over large areas. Frequently, bulk soil removal, with its attendant consequences, is a significant component of the majority of contamination incidents. Alternative techniques capable of removing contamination or exposure pathways without damaging or removing the soil are therefore of significant interest. An increasing number of old nuclear facilities are entering ‘care and maintenance’, with significant ground contamination issues. Phytoremediation — the use of plants’ natural metabolic processes to remediate contaminated sites is one possible solution. Its key mechanisms include phytoextraction and phytostabilisation. These are analogues of existing remedial techniques. Further, phytoremediation can improve soil quality and stability and restore functionality. Information on the application of phytoremediation in the nuclear industry is widely distributed over an extended period of time and sources. It is therefore difficult to quickly and effectively identify which plants would be most suitable for phytoremediation on a site by site basis. In response, a phytoremediation tool has been developed to address this issue. Existing research and case studies were reviewed to understand the mechanisms of phytoremediation, its effectiveness and the benefits and limitations of implementation. The potential for cost recovery from a phytoremediation system is also briefly considered. An overview of this information is provided here. From this data, a set of matrices was developed to guide potential users through the plant selection process. The matrices take the user through a preliminary screening process to determine whether the contamination present at their site is amenable to phytoremediation, and to give a rough indication as to what plants might be suitable. The second two allow the user to target specific plant species that would be most likely to successfully establish based on prevailing site conditions. The outcome of this study is a phytoremediation tool that can facilitate the development of phytoremediation projects, avoiding the need for in-depth research to identify optimal plant species on a case-by-case basis.

In 2009, remediation was initiated for a non-operational fuel cycle facility previously used for government contract work located in Windsor, Connecticut, USA. Radiological contaminants consisted primarily of high enriched uranium (HEU). Other radionuclides encountered in relatively minor amounts in certain areas of the clean-up included Co-60, Cs-137, Ra-226, Th-232 and low enriched uranium (LEU). Between 2009 and the spring of 2011, remediation efforts were focused on demolition of contaminated buildings and removal of contaminated soil. In the late spring of 2011, the last phase of remediation commenced involving the removal of contaminated sediments from portions of a 1,200 meter long gaining stream. Planning and preparation for remediation of the stream began in 2009 with submittal of permit applications to undertake construction activities in a wetland area. The permitting process was lengthy and involved securing permits from multiple agencies. However, early and frequent communication with stakeholders played an integral role in efficiently obtaining the permit approvals. Frequent communication with stakeholders throughout the planning and remediation process also proved to be a key factor in timely completion of the project. The remediation of the stream involved the use of temporary bladder berms to divert surface water flow, water diversion piping, a sediment vacuum removal system, excavation of sediments using small front-end loaders, sediment dewatering, and waste packaging, transportation and disposal. Many safeguards were employed to protect several species of concern in the work area, water management during project activities, challenges encountered during the project, methods of Final Status Survey, and stream restoration.

The paper describes the methodology that ONDRAF/NIRAS, the Belgian Agency for Radioactive Waste and Enriched Fissile Materials, in consultation with the metallurgical company who aims the Olen-site, is developing and wants to apply to arrive at a safe and sustainable long-term solution in Olen. The complex problematic in Olen and how this does fit in the legal missions of ONDRAF/NIRAS is also presented.

It has been known for many years that certain weather events (e.g., precipitation, low barometric pressure, etc.) can affect the results of outdoor gamma-ray surveys, particularly those where gamma spectroscopy is being used for the detection of uranium and its progeny. These effects are a result of a natural phenomenon that produces anomalous results that are contrary to the true concentrations present at the survey site. Gamma-ray survey results sometimes overestimate uranium concentrations during and immediately following rain or snowfall events. The effects that a precipitation event has upon a drive-over gamma-ray survey are discussed in this paper. Surveys were conducted using a sensitive array of sodium iodide (NaI) detectors mounted to an all-terrain vehicle in late fall/early winter where snow was encountered. Isotope-specific measurements taken before and during precipitation events are compared and visually presented in iso-contour maps.

Tottori University and the Japan Atomic Energy Agency carried out jointly the feasibility study on phytoremediation techniques, which apply to soil contaminated by the TEPCO’s Fukushima Dai-ichi NPP accident. This paper illustrates the results from experimental investigations. Experimental investigations include both water-culture tests and field tests. Several plants, mainly halophytes that can specifically absorb more Na than K, and others like sunflower demonstrated for other domestic large-scale tests, were water-cultured and examined for screening. Easily cultivated and harvested plants without harmful effects on subsequent cultivation were also considered. New Zealand spinach was selected as a candidate for demonstrations in fields. The field tests were carried out at two sites of different agricultural types in Minami-soma, Fukushima prefecture. Concentration of 137 Cs in soil is about 4.5 Bq/g-dry as the average of 10 cm depth. The aims of the field tests are to confirm absorption ability and environmental adaptation of the test plants and to document the cost and performance of projects. In conclusion, the absorption of 137 Cs activity per unit area (Bq/m 2 ) by New Zealand spinach could be approximately 0.5%. To achieve an effective result in removal of 137 Cs from soil in around a decade, it is required to find the plant which has ten or more times higher absorption capacity than New Zealand spinach. From the consistency of both results in water-culture and field tests, the water-culture test can be valid for screening. In addition, applicable sites will be limited to fields which are too steep or too narrow to use mechanical diggers, and which are free from any restrictions to enter.

Large volumes of radioactive waste were urgently buried in the Chernobyl Exclusion Zone (ChEZ) in the aftermath of the 1986 accident. Twenty-six years later, decisions must be taken about whether and how to remediate these sites. An attempt to resolve two key issues is described here: 1. How to assess the hazards posed by these facilities, recognizing that, for the foreseeable future, the Chernobyl Exclusion Zone will remain under institutional control? and 2. What standards to apply in deciding the extent of remediation? This paper presents an examination of the issues and proposes a simple decision-making process.

After the Fukushima Daiichi nuclear accident, Japan Atomic Energy Agency (JAEA) was chosen by the national government to conduct decontamination pilot projects at selected sites in Fukushima prefecture. Despite tight boundary conditions in terms of timescale and resources, the projects served their primary purpose to develop a knowledge base to support more effective planning and implementation of stepwise regional remediation of the evacuated zone. A range of established, modified and newly developed techniques were tested under realistic field conditions and their performance characteristics were determined. The results of the project can be summarized in terms of site characterization, cleanup and waste management. A range of options were investigated to reduce the volumes of waste produced and to ensure that decontamination water could be cleaned to the extent that it could be discharged to normal drainage. Resultant solid wastes were packaged in standard flexible containers, labelled and stored at the remediation site (temporary storage until central interim storage becomes available). The designs of such temporary storage facilities were tailored to available sites, but all designs included measures to ensure mechanical stability ( e.g. , filling void spaces between containers with sand, graded cover with soil) and prevent releases to groundwater (impermeable base and cap, gravity flow drainage including radiation monitors and catch tanks). Storage site monitoring was also needed to check that storage structures would not be perturbed by external events that could include typhoons, heavy snowfalls, freeze/thaw cycles and earthquakes.

A large-scale development in exploration and production of uranium ores in the Czech Republic was done in the 2 nd half of the 20 th century. Many uranium deposits were discovered in the territory of the Czech Republic. One of the most considerable deposits in the Czech Republic is the site Hamr na Jezere – Straz pod Ralskem where both mining methods — the underground mining and the acidic in-situ leaching — were used. The extensive production of uranium led to widespread environmental impacts and contamination of ground waters. Over the period of “chemical” leaching of uranium (ca. 32 years), a total of more than 4 million tons of sulphuric acid and other chemicals have been injected into the ground. Most of the products (approx. 99.5 %) of the acids reactions with the rocks are located in the Cenomanian aquifer. The contamination of Cenomanian aquifer covers the area larger then 27 km 2 . The influenced volume of groundwater is more than 380 million m 3 . The total amount of dissolved SO 4 2− is about 3.6 million tons. After 1990 a large-scale environmental program was established and the Czech government decided to liquidate the ISL Mine and start the remediation in 1996. The remediation consists of contaminated groundwater pumping, removing of the contaminants and discharging or reinjection of treated water. Nowadays four main remedial technological installations with sufficient capacity for reaching of the target values of remedial parameters in 2037 are used — the “Station for Acid Solutions Liquidation No. One”, the “Mother liquor reprocessing” station, the “Neutralization and Decontamination Station NDS 6” and the “Neutralization and Decontamination Station NDS 10”. It is expected that the amount of withdrawn contaminants will vary from 80 000 to 120 000 tons per year. Total costs of all remediation activities are expected to be in excess of 2 billion EUR.

In a green house pot experiment, the effects of three amendments, sulphur (S), ammonium sulphate ((NH 4 ) 2 SO 4 ) and ethylenediaminetetracetic acid (EDTA) were tested for phytoextraction of Cd and Zn by rapeseed ( Brassica napus L.). Elemental sulphur was applied as 20.00, 60.00, and 120.00 mg.kg −1 soil. EDTA was tested at a dose of 585.00 mg.kg −1 soil, and (NH 4 ) 2 SO 4 ) at a rate of 0.23 mg.kg −1 soil. All treatments received a base fertilization (Hogland) before sowing. Plants were harvested after 51 days of growth and shoot dry matter and soil samples were analysed for metal contents. All amendments caused a significant increase in Cd and Zn contents in plant shoots of all treatments than control treatment. Further, EDTA was most effective for extraction metals concentrations in shoot biomass but the plants showed significant signs of toxicity and yield were severely depressed. The addition of sulfur favorably influenced plant biomass production. The fertilized ammonium sulfate treatment resulted in the highest phytoextraction of Cd and Zn and the amounts of these metals accumulated in plant shoot exceeded by a factor of 4 and 3 respectively. Finally, Brassica napus could be used for soil remediation keeping its other uses which will make the contaminated site income generating source for the farmers.

A big affection of the rock environment and groundwaters occured during the chemical mining of uranium in the years 1966 to 1996 in the neighbourhood of the town Straz pod Ralskem in the Czech Republic. It is necessary to clean the residual technological solutions (RTS) from the underground. The pH of the solutions in some places is still less than 2 and the concentration of sulphates reachs up to 65 g/l. The remedial activities consist of pumping of the RTS from the ground and reprocessing of the RTS in the surface technologies. The implementation of the new neutralization technologies NDS ML and NDS 10 help us with increasing of the efficiency of the remedial process. The NDS ML technology (“Mother liquor reprocessing station”) started its operation in 2009 and it processes the concentrated technological solution from the evaporation station after the alum crystalization (mother liquor) with the concentration of total dissolved solids up to 250 g/l. The principle is the neutralization of the acid solutions with the aid of the lime milk. The suspension is then filtrated in the filter press, the filter cake is deposited in the tailings pond and the filtrate is injected back into the underground rock environment. The NDS 10 technology (“Neutralization and Decontamination Station NDS 10”) started its operation in 2012 and it works on the same technological principle as the NDS ML station. The difference is that the NDS 10 station can process higher volume (4.4 m 3 /min) of the RTS with lower concentration of total dissolved solids 20–25 g/l. This poster describes the experiences of the state enterprise DIAMO with putting of these two neutralization technologies into operation and with using of the lime milk neutralization in such a large scale.

To discover technologies that can be utilized for decontamination work and verify their effects, economic feasibility, safety, and other factors, the Ministry of the Environment launched the “FY2011 Decontamination Technology Demonstrations Project” to publicly solicit decontamination technologies that would be verified in demonstration tests and adopted 22 candidates. JAEA was commissioned by the Ministry of the Environment to provide technical assistance related to these demonstrations. This paper describes the volume reduction due to bio-ethanol, thermal decomposition and burning of organic materials in this report. The purpose of this study is that to evaluate a technique that can be used as biomass energy source, while performing volume reduction of contamination organic matter generated by decontamination. An important point of volume reduction technology of contaminated organic matter, is to evaluate the mass balance in the system. Then, confirming the mass balance of radioactive material and where to stay is important. The things that are common to all technologies, are ensuring that the radioactive cesium is not released as exhaust gas, etc.. In addition, it evaluates the cost balance and energy balance in order to understand the applicability to the decontamination of volume reduction technology. The radioactive cesium remains in the carbides when organic materials are carbonized, and radioactive cesium does not transfer to bio-ethanol when organic materials are processed for bio-ethanol production. While plant operating costs are greater if radioactive materials need to be treated, if income is expected by business such as power generation, depreciation may be calculated over approximately 15 years.

The Belgian radiation protection authority (Federal Agency for Nuclear Control – FANC) has published in March 2013 a decree regulating the acceptance of NORM residues by non-radioactive waste treatment facilities. This regulation is based on the concept of “work activities involving natural radiation sources” in the sense of article 40 of the 96/29/EURATOM directive. The disposal or processing facilities which accept NORM residues with an activity concentration above a generic exemption level will be considered as “work activities” and submitted to declaration according to the Belgian radiation protection regulations. On basis of this declaration, specific acceptance criteria for the different types of processing/disposal of the residues (disposal on landfill, recycling into building materials, etc.) are imposed. FANC has drafted guidelines for these acceptance criteria. A methodological guide for the operators of the concerned facilities was also published. Moreover, sites where significant quantities of NORM residues are or have been disposed, are subjected to an environmental monitoring in the framework of the national program of radiological surveillance of FANC. FANC also introduced in its regulations the concept of anthropogenic radon-prone areas: e.g. former phosphogypsum stacks have been defined as anthropogenic radon-prone areas, which allows some form of regulatory control of these sites.

During the operation of nuclear reactors important volume of liquid and solid radioactive wastes are generated, which, in normal conditions, becomes processed by stationary equipment by different methods to minimize their volume and then sent to specially constructed storages. The cases of accidents of Chernobyl and Fukushima showed that the localization of rejected big quantity of radioactive wastes is a prior problem for their further processing by stationary equipment. In this regard it is very important the processing of radioactive wastes on the contaminated areas to localize them by mobile equipment based on the efficient technologies. RADEON-NWM new technology allows resolving this problem. This technology is compact, completely automated, which makes possible to assemble it on a standard 40-ft by 7-ft trailer driven by heavy-duty truck. The new technology is fully elaborated, the necessary tests are conducted.

The U.S. Department of Energy is responsible for risk reduction and cleanup of its nuclear weapons complex. Remediation strategies for some of the contamination may include techniques that mitigate risk, but leave contaminants in place. Monitoring to verify remedy performance and long-term mitigation of risk is key to implementing these strategies and can be a large portion of the total cost of remedy implementation. Especially in these situations, there is a need for innovative monitoring approaches that move away from the cost- and labor-intensive point-source monitoring. In this paper, alternative approaches for monitoring are presented for vadose zone, groundwater, groundwater/surface water interface, and surface water. To illustrate integrated, systems-based monitoring, this paper focuses on vadose zone contaminant remediation to mitigate impact to groundwater. In this context, vadose zone contamination is a source, or potential source, to groundwater plumes. The monitoring design uses a systems-based approach focused on developing a conceptual site model that highlights key features that control contaminant flux to groundwater. These features are derived considering the unsaturated flow and contaminant transport processes in the vadose zone and the nature of the waste discharge. Diagnostic properties and/or parameters related to both short- and long-term contaminant flux to groundwater can be identified and targeted for monitoring. The resolution of monitoring data needed to correspond to a functionally useful indicator of flux to groundwater can be estimated using quantitative analyses and the associated unsaturated flow properties relevant to the targeted site and vadose zone features. This monitoring design approach follows the process of developing a quantitative conceptual model suitable for supporting projections of future flux to groundwater. Support for such projections is important because it is likely that, in many cases, remediation decisions for the vadose zone will need to be made based all or in part on projected impacts to groundwater, and monitoring will then be applied to verify that remedy goals are being met.

Data imaging and visual data assessment are veritable gold mines in the scientist’s quest to understand and accurately interpret numerical data. Graphical displays of various aspects of a dataset offer the analyst insight to the data that no mathematical computation or statistic can provide. It is difficult, at best, for even a skilled and observant statistician to understand the underlying structure of a dataset. Often, there is either too little data to get a good “picture” of the structure that might be present or there is so much data that one cannot readily assimilate it. Of course, the latter problem (too much data) is, in reality, no problem at all given the abilities of modern computers and software systems to manage large amounts of data. Advances in computer technology and the advent of the global positioning satellite system have enabled scientists from many fields of endeavor to collect and view data in its spatial context. Visual images constructed from spatially referenced data reveal the inherent richness and structure in the data and lead to more informed conclusions. So powerful is data collected with spatial context that a relatively new branch of mathematical statistics, geospatial statistics, has emerged. Geospatial statistics seek to exploit this context rich data form to better understand the spatial and co-relationships that might exist, but would be otherwise hidden in tabular data or obscured with classic statistical approaches. This paper (and accompanying presentation) will show the power that visual data assessment possesses to understand radiological scanning data and to make confident and accurate decisions based on the data images. It will challenge the traditional mathematical concept of detection limits for scanning. It will demonstrate that more data, even if the individual datum comprising the dataset is of “poorer quality” (i.e., has a larger uncertainty and, thus, a larger calculated minimum detection value), is significantly more powerful than a smaller dataset comprised of higher quality measurements. This presentation will cause the open-minded health physicist to rethink how they prescribe, collect, evaluate, and make decisions based upon radiological scan data.

Because of the very low level of 90Sr in the environmental soil samples and its determination by beta counting may take several weeks, we developed a procedure for ultratrace determination of 90Sr using collision reaction cell-inductively coupled plasma tandem mass spectrometry (CRC-ICP-MS/MS, Agilent 8800). Soil samples were dried at 105 °C and then heated in a furnace at 550 °C to remove any organics present. 500 g of each soil samples were aliquoted into 2000 ml glass beakers. Each Soils samples were soaked in 2 ppm Sr solution carrier to allow determination of chemical yield. The solid to liquid ratio was 1:1. Finally the soil samples were dried at 105 °C. Five hundred milliliters concentrated nitric acid and 250 ml hydrochloric acid volumes were added on 500 g soil samples. The samples were digested on hot plate at 80 °C to prevent spraying with continuous manual mixing. The leachate solution was separated. The solids were rinsed with 500 ml deionized water, warmed on a hot plate and the leachate plus previous leachate were filtered and the total volume was reduced to 500 ml by evaporation. Final leachate volume was transferred to a centrifuge tubes. The centrifuge tubes were centrifuged at 3,500 rpm for 10 min. The leachate was transferred to a 1 L beaker and heated on a hot plate to evaporate the leachate to dryness. The reside was re-dissolved in 100 ml of 2% HNO3 and reduced by evaporation to 10 mL. The solution was measured directly by CRC-ICP-MS/MS by setting the first quadruple analyzer to m/z 90 and introducing oxygen gas into the reaction cell for elimination isobar interference from zirconium-90. The method was validated by measurements of standard reference materials and applied on environmental soil samples. The overall time requirement for the measurement of strontium-90 by CRC-ICP-MS/MS is 2 days, significantly shorter than any radioanalytical protocol currently available.

Current requirements for site remediation and closure are standards-based and are often overly conservative, costly, and in some cases, technically impractical. Use of risk-informed alternate endpoints provides a means to achieve remediation goals that are permitted by regulations and are protective of human health and the environment. Alternate endpoints enable the establishment of a path for cleanup that may include intermediate remedial milestones and transition points and/or regulatory alternatives to standards-based remediation. A framework is presented that is centered around developing and refining conceptual models in conjunction with assessing risks and potential endpoints as part of a system-based assessment that integrates site data with scientific understanding of processes that control the distribution and transport of contaminants in the subsurface and pathways to receptors. This system-based assessment and subsequent implementation of the remediation strategy with appropriate monitoring are targeted at providing a holistic approach to addressing risks to human health and the environment. This holistic approach also enables effective predictive analysis of contaminant behavior to provide defensible criteria and data for making long-term decisions. Developing and implementing an alternate endpoint-based approach for remediation and waste site closure presents a number of challenges and opportunities. Categories of these challenges include scientific and technical, regulatory, institutional, and budget and resource allocation issues. Opportunities exist for developing and implementing systems-based approaches with respect to supportive characterization, monitoring, predictive modeling, and remediation approaches.

The Nuclear Energy Agency (NEA) Co-operative Programme for the Exchange of Scientific and Technical Information Concerning Nuclear Installation Decommissioning Projects (CPD) is a joint undertaking of a limited number of organisations, mainly from NEA member countries. The objective of the CPD is to acquire and share information from operational experience in decommissioning nuclear installations that is useful for future projects. The information exchange includes biannual meetings of the Technical Advisory Group (TAG) and supporting projects on topics. The TAG has decided to form a Task Group to review nuclear site restoration starting in March 2012 that involves nuclear operators, experts and regulators. The group is supported by the International Atomic Energy Agency (IAEA) that is leading similar work on legacy sites. Within NEA Counties, several nuclear sites are being restored for beneficial reuse. Restoration is normally considered the last activity in a sequence of decommissioning steps but increasingly the value of long-term planning and parallel remediation is being recognised. It is essential that regulators know that liabilities are well understood (well characterised) and there is adequate financial provision to carry on the remediation works. Operators are also learning that early intervention is needed to ensure prevention and minimisation of leaks and spills of radioactive and non-radioactive contaminants in order to reduce groundwater and soil contamination, thus reducing overall liabilities and ensuring protection of the environment. Early intervention needs to be guided by good practices that include adequate site characterisation, reliable conceptual models and defined goals. Currently most nuclear site restoration work takes place at the legacy nuclear sites. This work has emphasised the need for better clarity in terms of the regulatory expectations for site restoration. At other nuclear sites the drivers are less evident and there is a risk that land quality issues are overlooked. The aim of the Task Group is to share information on experiences, approaches and techniques for land quality management at selected nuclear sites to ensure risks to workers and the environment, costs and disruption to decommissioning programmes are minimised. The project will also highlight the successes and lessons to learn from experience of remediation that will be helpful to operational situations on nuclear sites. The paper will report on progress with analysis of national and site level questionnaires and early consideration of case studies. The questionnaires will provide a snapshot of the current status, issues and best practice with site restoration and the case studies will provide in depth illustrations of practice with nuclear site or remediation projects.

This report summarizes the data, including the cost parameters of the former iodine production facilities decommissioning project in Turkmenistan. Before the closure, these facilities were producing the iodine from the underground mineral water by the methods of charcoal adsorption. Balkanabat iodine and Khazar chemical plants’ sites remediation, transportation and disposal campaigns main results could be seen. The rehabilitated area covers 47.5 thousand square meters. The remediation equipment main characteristics, technical solutions and rehabilitation operations performed are indicated also. The report shows the types of the waste shipping containers, the quantity and nature of the logistics operations. The project waste turnover is about 2 million ton-kilometers. The problems encountered during the remediation of the Khazar chemical plant site are discussed: undetected waste quantities that were discovered during the operational activities required the additional volume of the disposal facility. The additional repository wall superstructure was designed and erected to accommodate this additional waste. There are data on the volume and characteristics of the NORM waste disposed: 60.4 thousand cu.m. of NORM with total activity 1 439 × 10 9 Bq (38.89 Ci) were disposed at all. This report summarizes the project implementation results, from 2009 to 15.02.2012 (the date of the repository closure and its placement under the controlled supervision), including monitoring results within a year after the repository closure.