Bentonite, a material mainly used in buffer and backfill of the engineering barrier system (EBS) that makes up the deep geological repository, is a porous material, thus porewater could be contained in it. The porewater components will be changed through ‘water exchange’ with groundwater as time passes after emplacement of subsystems containing bentonite in the repository. ‘Water exchange’ is a phenomenon in which porewater and groundwater components are exchanged in the process of groundwater inflow into bentonite, which affects swelling property and radionuclide sorption of bentonite. Therefore, it is necessary to assess conformity with the performance target and safety function for bentonite. Accordingly, we reviewed how to handle the ‘water exchange’ phenomenon in the performance assessment conducted as part of the operating license application for the deep geological repository in Finland, and suggested studies and/or data required for the performance assessment of the domestic disposal facility on the basis of the results. In the previous assessment in Finland, after dividing the disposal site into a number of areas, reference and bounding groundwaters were defined considering various parameters by depth and climate change (i.e. phase). Subsequently, after defining reference and bounding porewaters in consideration of water exchange with porewater for each groundwater type, the swelling and radionuclides sorption of bentonite were assessed through analyzing components of the reference porewater. From the Finnish case, it is confirmed that the following are important from the perspective of water exchange: (a) definition of reference porewater, and (b) variations in cation concentration and cation exchange capacity (CEC) in porewater. For applying items above to the domestic disposal facility, the site-specific parameters should be reflected for the following: structure of the bedrock, groundwater composition, and initial components of bentonite selected. In addition, studies on the following should be required for identifying properties of the domestic disposal site: (1) variations in groundwater composition by subsurface depth, (2) variations in groundwater properties by time frame, and (3) investigation on the bedrock structure, and (4) survey on initial composition of porewater in selected bentonite The results of this study are presumed to be directly applied to the design and performance assessment for buffer and backfill materials, which are important components that make up the domestic disposal facility, given the site-specific data.

Most of the drinking water dams managed by the local governments in Korea are earthfill dams, and these dams have almost no geotechnical property information necessary for seismic performance evaluation. Nevertheless, in the rough planning stage for improving seismic safety for these dams, it is necessary to classify their relative seismic hazard against earthquakes and conduct an additional ground investigation. The zero seismic failure probability curve is a curve suggested in this study in which the probability of failure due to an earthquake becomes ‘0’ regardless of the geotechnical properties of the earthfill dam. By examining the method and procedure for calculating failure probability due to an earthquake suggested in previous researches, the zero seismic failure probability curves for an earthquake in 1,000-year and 2,400-year return periods in Korea were presented in the form of a hyperbola on the plane of the dam height versus freeboard ratio (ratio of freeboard to dam height), respectively. The distribution characteristics of the dam height and the freeboard ratio of 81 Korean earthfill dams were presented. The two proposed zero seismic failure probability curves are shown on the plane of the dam height versus freeboard ratio, and the relative seismic hazard of 81 dams can be classified into three groups using these curves as boundaries. This study presented the method of classifying the relative seismic hazard and the classification result.

During the treatment of spent nuclear fuel, radioactive iodine is generated in a liquefied or gaseous form in a specific process. In the case of iodine 129, it is a long-lived nuclide with a very long halflife and has high groundwater mobility under repository conditions. Despite showing a low radioactivity value, research on the management of radioactive iodine from a long-term perspective is continuously being performed. Although research has been conducted using borosilicate glass as a medium for solidifying iodine, compatibility of I in borosilicate glass is very small and the volatility is high in the solidification process. So it is not suitable as a solidified substance of iodine. Therefore, studies on other solidification media to replace them are continuously being conducted. Our research team tried to develop a new medium that can contain iodine in a solidified body stably through a simple heat treatment process and can improve problems such as volatility and waste loading. Iodine is captured as AgI in the Ag ion-exchanged zeolite. So, TeO2, Ag2O, and Bi2O3 having a high AgI loading rate were used as main components. It was named TAB after taking the first letter of each element. In previous studies, the physical properties, structure, and chemical stability of TAB materials were confirmed. PCT (Product Consistent test) was performed to confirm chemical stability. It is mainly used to compare the chemical stability of glass materials with other glass materials, but there are limitations in evaluating the long-term chemical stability of materials. In this experiment, we tried to evaluate the long-term stability of TAB and compare it with borosilicate, which is conventionally used to treat radioactive waste. In addition, we tried to understand the leaching behavior inside the TAB medium. For this purpose, ASTM C1308 test was performed for 365 days, and distilled water and KURT groundwater were used as leachates to examine the effect of ions in the groundwater on the solidified body. To analyze the leaching behavior, ICP-MS and ICP-OES analyses were performed, and the cross-section of the sample after leaching was observed through SEM.

깔따구 (Diptera: Chironomidae)는 저서성 대형무척추동 물로 환경오염 및 수질 모니터링에 이용되는 중요한 지표생물이다. 본 연구에서는 인천 수돗물 정수장에서 발견된 깔따구류의 정밀한 종 동정을 위해 형태적 분류와 미토콘드리아 DNA에서 cytochrome c oxidase subunit I (COI) 유전자의 염기서열을 이용하여 분석하였다. 정수장 6곳의 20 개체는 안개무늬날개깔따구 (Chironomus kiiensis) 12개체, 노랑털깔따구 (Chironomus flaviplumus) 6개체, 등깔따구 (Chironomus dorsalis) 1개체, 용산무늬깔따구 (Polypedilum yongsanensis) 1개체 등 4종으로 확인되었다. 각 깔따구 종의 형태적 특징은 두부, 하순기절, 대악, 안테나, 발톱의 형 태적 특징을 살펴보았다. NCBI Genbank에 등록된 깔따구 17종 21개체의 COI 염기서열을 바탕으로 본 연구에서 조사된 20개체의 계통진화적 분석한 결과 각 4종의 깔따구 COI 염기서열은 등록된 동인 종과 높은 상동성을 보이며 (99~100%) 같은 계통군 (clade)으로 나타났다. 이러한 결과는 국내 깔따구의 종 동정을 위한 형태적 - 유전적 정보를 통합적으로 제공함으로 담수생태계의 모니터링을 위한 주요한 정보로 활용될 것이다.

원자력발전소를 운영하게 되면 사용후핵연료와 같은 고준위방사성폐기물이 필연적으로 발생한다. 이러한 고준위방사성폐 기물을 처분하기 위해 심층처분방식이 가장 적합한 대안으로 알려져 있으며 고준위방사성폐기물은 공학적방벽과 천연방벽에 둘러 쌓여 지하 500~1,000 m 깊이의 심지층에 처분된다. 이 중 압축 벤토나이트 완충재는 공학적방벽의 가장 중요한 구성요소이다. 완충재는 처분용기와 자연 암반 사이에 위치해 있기에 주변 지하수 흐름으로부터 처분용기를 보호하고 처분 용기로부터 핵종이 유출되는 것을 저지하는 역할을 한다. 주변 지하수 흐름으로 인한 완충재의 불포화 함수특성 규명은 전체 공학적방벽의 성능을 평가하는데 있어 매우 중요하다고 할 수 있다. 따라서 본 연구에서는 실내 시험을 수행하여 국내 압축 벤토나이트 완충재의 건조밀도, 구속조건 여부, 그리고 건조 및 포화 이력에 따른 압축 벤토나이트 완충재의 함수특성곡선을 도출하여 분석하였다. 구속 조건하에서 건조밀도에 따른 함수특성곡선은 큰 차이를 보이지 않았다. 또한 비구속 조건이 구 속 조건에 비해 보다 큰 수분흡입력을 나타냈으며, 아울러 포화 과정보다 건조 과정에서 보다 큰 수분흡인력이 측정되었다.

본 연구는 미나리의 종자를 이용하여 가정에서 청정재 배가 가능한 재배키트를 개발하고자 실시하였다. 미나리 3가지 계통들의 발아율을 조사한 결과 계통 IT 232354 의 최초발아율과 최종발아율이 가장 높아 가정용 재배키 트에 사용될 종자로 선발하였다. 계통 IT 232354를 이 용하여 가정용 재배키트 개발을 위한 실험을 진행한 결 과 같은 재배키트에서 생육한 동일한 종근을 이용하여 3회까지 재배 및 수확이 가능하였으며 4회차가 되면서 생육이 급격히 저하되었다. 따라서 1회 파종으로 가능한 수확 횟수는 3회였으며, 양액의 종류에 따른 미나리 생 육을 조사한 결과 전체적인 생육은 미나리전용 양액이 가장 저조하였으며, 지상부 생육의 경우에는 엽경채류 전용액비와 아미노산발효부산액이 모두 비슷하였으나 지 하부 생육의 경우 아미노산발효부산액보다 엽경채류 전 용액비 처리구의 생육이 더 좋았다. 또한 4회 연속 재배 ·수확을 할 경우 생존율은 아미노산발효부산액이 100% 였으며, 엽경채류 전용액비는 96.4%, 그리고 미나리 양액은 49.8%로 가장 낮았다. 키트 유형에 대한 생육은 초기 생육은 2구형이 3구형에 비해 약간 증가하는 경향 을 보이지만 3회차가 되면서 생육차이가 없었다. 또한 재배키트 하나의 전체 수확량의 경우 3구형이 2구형보 다 훨씬 높은 결과를 나타내었다. 본 실험 결과를 종합 하면 친환경 제재인 아미노산발효부산액과 엽경채류 전 용액비를 이용하여 3구형 재배키트에서 미나리를 재배한 다면 1회 파종으로 3회까지 재배·수확이 가능할 것이다. 친환경 자제인 아미노산발효부산액만을 이용하여 자체 제작한 미나리 재배키트에 종자를 이용한 미나리 생산이 가능하여 가정용 재배키트로의 개발 가능성을 확인하였 다. 이는 미나리 외 채소재배키트의 개발에도 큰 영향을 줄 뿐 아니라 종자 산업의 다양화에 크게 기여할 것으 로 사료된다.

The sewage and wastewater (SAW) are a well-known major source of eutrophication and greentide in freshwaters and also a potential source of thermal pollution; however, there were few approaches to thermal effluent of SAW in Korea. This study was performed to understand the behavioral dynamics of the thermal effluents and their effects on the water quality of the connected streams during winter season, considering domestic sewage, industrial wastewater and hot spring wastewater from December 2015 to February 2016. Sampling stations were selected the upstream, the outlet of SAW, and the downstream in each connected stream, and the water temperature change was monitored toward the downstream from the discharging point of SAW. The temperature effect and its range of SAW on the stream were dependent not only on the effluent temperature and quantity but also on the local air temperature, water temperature and stream discharge. The SAW effects on the stream water temperature were observed with temperature increase by 2.1~5.8℃ in the range of 1.0 to 5.5 km downstream. Temperature effect was the greatest in the hot spring wastewater despite of small amount of effluent. The SAW was not only related to temperature but also to the increase of organic matter and nutrients in the connected stream. The industrial wastewater effluent was discharged with high concentration of nitrogen, while the hot spring wastewater was high in both phosphorus and nitrogen. The difference between these cases was due to with and without chemical T-P treatment in the industrial and the hot spring wastewater, respectively. The chlorophyll-a content of the attached algae was high at the outlet of SAW and the downstream reach, mostly in eutrophic level. These ecological results were presumably due to the high water temperature and phosphorus concentration in the stream brought by the thermal effluents of SAW. These results suggest that high temperature of the SAW needs to be emphasized when evaluating its effects on the stream water quality (water temperature, fertility) through a systematized spatial and temporal investigation.

Hot water extracts from 16 domestic edible mushrooms including Pleurotus ferulae (Lanzi) X.L. Mao, Lentinula edodes (Berk.) Pegler, and Hypsizygus marmoreus (Peck) H.E. Bigelow, which are commercially available, were used for determining the cosmetic potential of these mushrooms. In this study, we carried out in vitro functional experiments to determine the inhibitory effects of these extracts on L-DOPA oxidation of tyrosinase and melanin synthesis. Based on the results of these experiments, H. marmoreus (Peck) H.E. Bigelow No. 10 and No. 15 were selected for further analysis. We analyzed the melanin synthesis inhibitory activity, TRP1 and MITF expression via real-time PCR, and Fontana Masson staining in artificial skin Neoderm®-ME. Taken together, we observed that the hot water extract from H. marmoreus (Peck) H.E. Bigelow (No. 15) had better whitening effect than the extracts of other mushrooms. Thus, it can be a potential source of skin-whitening agent

본 연구에서는 2001년부터 2010년까지의 사료용 옥수수 및 밀의 수입량을 조사하고, 이를 바탕으로 가상수 개념을 활용하여 사료 곡물 수입에 따른 농업용수 및 농경지 대체 효과를분석하였다. 그 결과 사료용 옥수수와 밀을 통하여 수입되는가상수는 평균적으로 6,757백만 m3/yr 및 1,405백만 m3/yr씩 수입되는 것으로 분석되었다. 따라서 두 사료곡물을 통하여 약8,162백만 m3/yr만큼의 농업용수를 대체 효과가 있음을 의미하는데, 이는 농업용수 수요량의 51.5%에 해당되는 양이다. 한편 전적으로 해외수입에 의존하는 사료용 옥수수와 밀을 국내생산으로 대체하기 위해 필요한 잠재적 농경지 면적은 평균적으로 1,945천 ha와 285천 ha인 것으로 추정되었다. 이와 같이대외 의존도가 높은 상황에서 곡물 수급이 원활하지 않은 경우, 농작물 생산에 필요한 기술 등의 여력이 충분하더라도 수자원 및 농경지 부족으로 필요한 양의 농작물 생산에 어려움을 겪을 수도 있다. 특히 한정된 수자원에 대하여 농업, 생활및 공업용수 등의 이용에 대한 갈등을 야기할 수 있다. 위와같이 사료용 옥수수와 밀의 수입을 통한 농업용수의 양과 경작지 대체 면적이 많은 상황에서 정부는 2010년 기준으로37.5%인 자급률을 2015년과 2020년에 각각 41.2%와 44.4%로 목표치 설정하였다. 이와 같이 설정한 식량자급률 목표치달성을 위해서는 사료용 곡물의 국내생산 증대가 불가피함을고려할 때, 향후 사료용 곡물 국내생산을 위한 농업용수와 경작지 확보가 필수적이며, 이를 위한 다양한 정책 수립시 수자원 및 농경지 소요량 추정 등의 기초 자료로 본 연구 결과가활용될 수 있을 것으로 판단된다. 본 연구는 축산사료의 주요원료인 옥수수와 밀에 초점을 두고 연구가 이루어졌는데, 향후 기타 사료작물 및 조사료에 관련된 연구가 추가로 이루어진다면, 보다 종합적으로 국내 사료용 곡물의 국내자급 향상을 위한 정책대응 방안 탐색이 가능할 것으로 판단된다.

최근에 "선박의 밸러스트수와 침전물의 제어 및 관리를 위한 국제협약 "이 채택되면서 국내에서도 이 국제협약을 수용하기 위한 방안이 필요하다. 외국의 밸러스트수 제어/관리 동향을 살펴보고, 국내의 환경관계법규들을 비교·검토함으로써 밸러스트수관리협약을 수용하기 위한 국내 입법화 방안을 제시하였다.

The adsorption of heavy metals in the waste water carried out on the various domestic clays and waste pottery. The effect of parameters such as pH, temperature, adsorption time and coexisting cations on the adsorption ability and characteristics were investigated to find out whether the clays could be used as adsorbents. Adsorption equilibrium was reached within 20 minutes on all the clays. The optimum pH was found to be above 5. When other cations such as Cu(II) or Zn(II) coexisted with Pb(II), the adsorption amount of Pb(II) decreased because of competing adsorption.

국내 정수장.수도전.간이상수도등 2000여 곳의 수질을 환경부가 검사한 결과, 지역별로 세균.무기 이온등 몇몇 항목에서 환경기준을 초과한 것이 밝혀졌다. 이중에서 문제가 되고 있는 질산성 질소.암모니아성 질소.불소.염소등의 농도를 임의로 조작한 후, 시중에 유통되고 있는 가정용 정수기 모듈로 정수처리시켰을 때의 효과와 지역별로 문제시되는 항목들을 효과적으로 제거하기 위한 적당한 분리막을 선정하고자 측정 검토하였다. 정수처리하여 얻은 투과수를 일정 온도 하에서 보관하고, 일정 시간마다 세균수를 측정하여 세균수와 온도 및 시간과의 관계를 측정 조사함으로써 막 사용을 좀 더 효율적으로 할 수 있게끔 검토하였다.

Heat transfer performance improvement by fin and groovs is studied for condensation of R-11 on integral-fin tubes. Eight tubes with trapczodially shaped integral-fins having fin density from 748 to 1654fpm(fin per meter) and 10, 30 grooves are tested. A plain tube having the same diameter as the finned tubes is also used for comparison. R-11 condensates at saturation state of 32 ℃ on the outside tube surface coded by inside water flow. All of test data are taken at steady state. The heat transfer loop is used for testing singe long tubes and cooling is pumped from a storage tank through filters and folwmeters to the horizontal test section where it is heated by steam condensing on the outside of the tubes. The pressure drop across the test section is measured by menas pressure gauge and manometer. The results obtained in this study is as follows : 1. Based on inside diameter and nominal inside area, overall heat transfer coefficients of finned tube are enhanced up to 1.6 ~ 3.7 times that of a plain tube at a constant Reynolds number. 2. Friction factors are up to 1.6 ~ 2.1 times those of plain tubes. 3. The constant pumping power ratio for the low integral-fin tubes increase directly with the effective area to the nominal area ratio, and with the effective area diameter ratio. 4. A tube having a fin density of 1299fpm and 30 grooves has the best heat transfer performance.

This study analyzed the temporal and spatial characteristics of water quality for five hydropower dam reservoirs in South Korea. Water temperature, pH, dissolved oxygen, and chlorophyll-a (Chl-a) showed high fluctuations in summer and autumn at all reservoirs, indicating the existence of seasonal effects. At all five reservoirs, the concentrations of suspended solids (SS) and total nitrogen (TN) fell under the “slightly bad” category and those of total organic carbon (TOC) fell under the “slightly good” category or higher, according to “the standard for living environment of lake water quality.” Variations in the concentration ranges and degrees of change in SS, TN, and TOC among reservoirs were observed, indicating the influences of rainfall, surrounding environments, and seasonal changes. Daecheong and Namgang Dam showed high Chl-a concentrations in summer, indicating that the metabolism of microbial communities, such as algae, was active.

Existing agricultural reservoirs are considered as alternative source for the water welfare of rural area. In this study, domestic water supply potential of 476 reservoirs, which has storage capacity more than one million cubic meter, out of 3,377 agricultural reservoirs managed by Korean Rural Community Corporation (KRC) were investigated. Among them water quality of 136 reservoirs met the criteria of domestic water source which show less than COD 3 ppm. Available amount for domestic water of reservoirs, which meet the water quality, for ten year return period of drought was analyzed with reservoir water balance model. The results showed that 116 reservoirs has potential for supplementary domestic water supply while satisfying irrigation water supply. Finally, economic analysis using Net Present Value (NPV), Benefit–Cost (B/C) ratio, Internal Rate of Return (IRR), and Profitability Index (PI) methods was also conducted. The analysis showed that 19 reservoirs satisfied economic feasibility when water is provided from reservoir outlet but only 9 reservoirs meet the economic feasibility if water delivered from a reservoir to treatment plant by newly built conveyance canal. In order to supply the domestic water through the agricultural reservoirs managed by KRC, it is necessary to flexibly interpret and operate the ‘Rearrangement of Agricultural and Fishing village Act’. Also, it is reasonable to participate in the water service business when there is a supply request from other Ministries. In addition, the KRC requires further effort to change the crop system for saving water and improve efficiency of irrigation systems.

This study was performed to improve water demand estimation and analize correlation between generation of domestic sewage and domestic water use. To improve the prediction of water demand estimation, new water demand equation was developed. The results is as follows. InQt = β0 + β₁InPt + β₂InYt + β₃InHt + εt By using the statistical analysis of the "generation of domestic sewage" and "domestic water use", the regression equation between them is formed. The result is as follows. ＿ Generation of domestic sewage = 0.8487 × Domestic water use + 684.57 (R² = 0.972)