The acceptance criteria for low and intermediate level radioactive waste disposal facilities in Korea to regulate that homogeneous waste, such as concentrated waste and spent resin, should be solidified. In addition, solidification requirements such as compressive strength and leaching test must be satisfied for the solidified radioactive waste solidified sample. It is necessary to develop technologies such as the development of a solidification process for radioactive waste to be solidified and the characteristics of a solidification support. Radioactive waste solidification methods include cement solidification, geopolymer solidification, and vitrification. In general, low-temperature solidification methods such as cement solidification and geopolymer solidification have the advantage of being inexpensive and having simple process equipment. As a high-temperature solidification method, there is typically a vitrification. Glass solidification is generally widely used as a stabilization method for liquid high-level waste, and when applied to low- and intermediate-level radioactive waste, the volume reduction effect due to melting of combustible waste can be obtained. In this study, the advantages and disadvantages of the solidification process technology for radioactive waste and the criteria for accepting the solidified material from domestic and foreign disposal facilities were analyzed.

During and after the construction of LILW disposal facilities, the decrease of groundwater head potential has been monitored. In addition, an increase of the electrical conductivity (EC) has been observed in several monitoring wells installed along the coastal coastline. Monitoring activity for groundwater head potential and hydrogeochemical properties is important to reduce the uncertainty in the evaluation of groundwater flow characteristics. However, the data observed in the monitoring wells are spatial point data, so there is a limit to the dimension. Several researchers evaluated groundwater head potential changes and seawater intrusion (SWI) potential for disposal sites using groundwater flow modeling. In case of groundwater flow modeling results for SWI, there is a spatial limit in directly comparing the EC observed in the monitoring wells with the modeling results. In a recent study, it was confirmed that the response of the long-range ground penetraiing radar (GPR) system was severely attenuated in the presence of saline groundwater. In order to reduce the spatial constraint of the groundwater monitoring wells for SWI, the characteristics of SWI within the disposal facility site by using the the results of a recent study of the long-range GPR system were investigated and evaluated in this study.

Currently, the Gyeongju disposal facility is planned to be operated as a complex disposal facility with three types: cave disposal, surface disposal, and landfill disposal. Approximate method and arrangement have been decided up to the 1st, 2nd, and 3rd stage disposal facilities, but the optimal method for the arrangement of the entire complex disposal facility has not been established. When establishing the subsequent disposal facility arrangement plan, the generation prospect and disposal capacity setting plan for each level of radioactive waste was established, and the disposal capacity of the subsequent disposal facility, the disposal facility method, etc. were reviewed and reflected. Among the items for deriving an efficient management plan, KEPCO E&C is going to first derive a site arrangement plan for each disposal facility of 800,000 drums of radioactive waste, and has drawn up a plan for each scenario through collaboration with other organizations. When establishing the subsequent disposal facility arrangement plan, the generation prospect and disposal capacity setting plan for each level of radioactive waste was established, and the disposal capacity of the subsequent disposal facility, the disposal facility method, etc. were reviewed and reflected.

It has been discovered that the isosaccharinic acid (ISA) formed in a cellulose degradation leachate were capable of forming soluble complexes with thorium, uranium (IV) and plutonium. Since 1993, the ISA has received particular attention in the literature due to its ability to complex a range of radionuclides, potentially affecting the migration of radionuclides. ISA is formed as a result of interactions between cellulosic materials within the waste inventory and the alkalinity resulting from the use of cementitious materials in the construction of the repository. In an alkaline cementitious environment, cellulose degrades mainly via a peeling-off reaction. The main degradation product is ISA, a polyhydroxy type of ligand forming stable complexes with tri- and tetravalent radionuclides. ISA can have an adverse effect on the sorption of radionuclides to an extent which depends on its concentration in the cement pore water and potentially enhance their mobility. The concentration of ISA is governed by several factors such as cellulose loading, cement porosity, extent of cellulose degradation, etc. The sorption of ISA on cement, however, is the process which governs the concentration of ISA in the pore water. According to the experimental result from a literature, the ISA concentration in facilities with a cellulose loading of 5% is calculated to be of the order of 10−4 M. At this level, the effect of cellulose degradation products on radionuclide sorption is negligibly small. Recently in Korea, cellulous limits as waste acceptance criteria is studying and planning to prepare the detailed requirement for near surface radioactive waste disposal facilities. It is desirable to suggest consideration on cellulose disposal limits around the time that the regulatory body and concern organizations establish the cellulose disposal limits as follows. Firstly, identify the cellulose effect on the sorption of the nuclides as cementitious disposal environments such as affected nuclides, threshold value and contribution to radiological risks under domestic disposal environment. Secondly, make sure and consider the difference between lab-scale experimental conditions and probability occurring in real disposal conditions such as probability for generation and persistence of pH in cellulosic material disposal conditions and cellulosic material disposal methods. Finally, consider characterization of cellulosic material such as polymerization, contents of cellulose in law material and time of degradation process. As a result, desirable cellulose limits are to set up for both safety and economic aspect.

Deep geological disposal (DGD) of spent nuclear fuels (SNF) at 500 m–1 km depth has been the mainly researched as SNF disposal method, but with the recent drilling technology development, interest in deep borehole disposal (DBD) at 5 km depth is increasing. In DBD, up to 40SNF canisters are disposed of in a borehole with a diameter of about 50 cm, and SNF is disposed of at a depth of 2–5 km underground. DBD has the advantage of minimizing the disposal area and safely isolating highlevel waste from the ecosystem. Recently, due to an increasing necessity of developing an efficient alternative disposal system compared to DGD domestically, technological development for DBD has begun. In this paper, the research status of canister operation technology and plans for DBD demonstration tests, which subjects are being studied in the project of developing a safety-enhancing high-efficiency disposal system, are introduced. The canister operation technology for DBD can be divided into connection device development and operation technology. The developing connection device, emplacing and retrieving canisters in borehole, adopted the concept of a wedge thus making replacement equipment at the surface unnecessary. The new connection device has the advantage of being well applied with emplacement facilities only by simple mechanical operation. The technology of operating a connection device in DBD can be divided into drill pipe, coiled tubing, free-drop, and wireline. The drill pipe is a proven method in the oil industry, but requiring huge surface equipment. The coiled tubing method uses a flexible tube and shares disadvantages as the drill pipe. The free-drop is a convenient method of dropping canister into a borehole, but has a weakness in irretrievability in an accident. Finally, the wireline method can be operational on a small scale using hydraulic cranes, but the number of operated canisters at once is limited. The test facility through which the connection device is to be tested consists of dummy canister, borehole, lifting part, monitoring part, and connecting device. The canister weight is determined according to the emplacement operation unit. The lifting part will be composed following wireline consisting of a crane, a wire and a winding system. The monitoring part will consist of an external monitoring system for hoists and trolleys, and an internal monitoring system for the connection device’s location, pressure, and speed. In this project, a demonstration test will be conducted in a borehole with 1km depth, 10 cm diameter provided by KAERI to verify operation in the actual drilling environment after design improvement of the connecting device. If a problem is found through the demonstration test, the problem will be improved, and an improved connection device will be tested to an extended borehole with a 2 km depth, 40 cm diameter.

Response measures to the resource circulation society and the new climate plan must be prepared by the central government in conjunction with local governments. The future directions of such measures can be established by investigating and evaluating trends in waste disposal currently in use by various cities and provinces. Against this backdrop, the current status of municipal waste generation and disposal in 16 Korean cities and provinces was examined. Although the percentage of waste recycled has increased, the rate of increase is declining. The percentage of waste disposed of in landfills has declined over time, but some landfills have already reached their limits. The amount of waste incinerated has grown more than the amounts recycled or disposed of in landfills. It will soon be necessary to develop measures that further increase the percentage of waste disposed of via incineration and improve the recovery of incineration-related energy. All cities and provinces should strive to improve the operating performance of their incineration facilities while reducing operating costs.

지금껏 안정적으로 폐기물을 처분해왔던 방법에 변화를 가져올 정책과 국제협정이 최근 제정 및 체결되었다. 첫 번째는 2016년 5월 29일 자원순환기본법이 제정･공포되어 2018년 1월 1일부터 시행될 예정으로 자원순환사회 기반을 구축하기 위한 제도적 기틀을 마련한 것이다. 지금까지 자원의 절약과 재활용촉진에 관한 법률에 의해 추진해오던 것에 비하면 자원순환에 관해서는 다른 법률에 우선하기에 폐기물 처분방법에 있어 변화가 있을 것으로 본다. 두 번째는 2015년 12월 프랑스 파리에서 열린 2020년 이후의 신기후체제가 논의되어 모든 국가가 온실가스 감축에 참여하는 파리협정을 체결하였다. 이로 인해 폐기물부문도 온실가스 감축을 위한 방안과 실행계획 마련이 있을 것으로 본다. 이 같은 정책과 국제협정이 지금껏 안정적으로 처분해왔던 폐기물관리에 일정부분 변화를 가져올 수밖에 없는 상황이다. 감량 목적의 단순 소각처분이 아닌 자원이 순환하고 온실가스 감축을 위해 에너지를 최대한 회수하기 위한 방안 마련이 필요한 것이다. 우리나라는 선진화된 폐기물정책 시행으로 인해 폐기물 감량이나 재활용에 있어서는 선도적 역할을 담당해오고 있으나 소각에너지 회수에 있어서는 미흡한 면이 있다. 이에 본 연구에서는 우리나라의 시도별 도시폐기물의 발생 및 처분 그리고 소각시설에 대한 현황을 2000년 이후 2014년까지 5년 주기의 변화 추이를 살펴봄으로써 앞으로 자원순환 정책과 기후변화 협약에 대응할 수 있는 방향성을 제언하고자 한다.