초록 ▼

□ 최종(연차)목표
ㅇ 지구환경변화 대응 지하수확보 통합솔루션 제공을 위한 핵심요소기술 개발 : 기후변화에 따른 지하수자원 취약성도 작성 및 변동예측모델 개발, 재순환/빗물주입 최적 인공함양시스템(ASR) 개발 및 파일럿 규모 (30만 m³/년) ASR 시설 구축, 고부가 제주지하수 생성/순환기작 규명 및 개발 가능지 확보 (30만m³/년, 3개소 이상)

□ 개발내용 및 결과
ㅇ 기후변화에 따른 금강수계 지하수자원/오염 취약성도 작성 및 DB구축, 지하수 오염취약성 평가, 기후변화 대응 미래 지하수 유동 변화

□ 최종(연차)목표
ㅇ 지구환경변화 대응 지하수확보 통합솔루션 제공을 위한 핵심요소기술 개발 : 기후변화에 따른 지하수자원 취약성도 작성 및 변동예측모델 개발, 재순환/빗물주입 최적 인공함양시스템(ASR) 개발 및 파일럿 규모 (30만 m³/년) ASR 시설 구축, 고부가 제주지하수 생성/순환기작 규명 및 개발 가능지 확보 (30만m³/년, 3개소 이상)

□ 개발내용 및 결과
ㅇ 기후변화에 따른 금강수계 지하수자원/오염 취약성도 작성 및 DB구축, 지하수 오염취약성 평가, 기후변화 대응 미래 지하수 유동 변화 및 예측 모델링 프로그램 개발
ㅇ 인공함양 최적지 선정 기법 개발 및 파일럿 규모 (216개 수막시설 인공 함양량 66만m³/년) 인공함양시스템 구축, 수막재배 지하수사용량 국내 최초 실증 평가(6.77억m³/년, 지하수이용량의 18.2%), 라돈, 철망간 수 처리시스템 개발 및 운영
ㅇ 고부가가치 제주도 지하수(탄산수) 개발가능지 3차원 지질 개념 모형 구축, 고미네랄수/탄산수 기원 및 생성 기작 해석, 안정적 탄산수/고미네랄수 수질특성 47.1만m³/년 개발가능지/개발가능량 확보

□ 기대효과
ㅇ 기후변화에 따라 예상되는 지역별 물부족에 대비한 지하수 확보로 물공급 안정성 도모 및 국가 수자원 정책 활용
ㅇ 수막재배 인공함양기술에 따른 농업용 물부족 및 녹색영농에 기여
ㅇ 물산업 활용을 위한 고부가 지하수의 병입수 시장 및 의료산업 단지 활용을 위한 기반 구축

□ 적용분야
ㅇ 미래 기후변화에 따른 국가 수자원 정책 수립의 기반자료
ㅇ 녹색영농 기반 기술 : 원예단지 및 기타 수막재배 시설 활용
ㅇ 지자체 물산업 시장 확대를 위한 기반 기술 제공

(출처 : 보고서 요약서 3p)

Abstract ▼

Watershed scale vulnerability of the groundwater resource and recharge characteristics were evaluated according to climate change in Geum river basin. Measurement and validation of base flow for estimation of groundwater recharge, Infiltration test and assessment of in-situ soil permeability, Ground

Watershed scale vulnerability of the groundwater resource and recharge characteristics were evaluated according to climate change in Geum river basin. Measurement and validation of base flow for estimation of groundwater recharge, Infiltration test and assessment of in-situ soil permeability, Groundwater flow modeling according to climate change, assessment of groundwater vulnerability to contamination, and environmental ecological evaluation, and groundwater quality monitoring were carried out in this study. Also, monitoring and modeling were performed in Jeju Island to evaluate groundwater resource change according to sea level rise.

Base flow was measured in outlets at 17 locations except for the area around river mouth. The results revealed that flow data provided by WAMIS was very different from what was measured in this study, which is coming from rating curve suitable for high flow. The rating curves for low flow need to be developed to evaluate base flow. And, base flow separation using PART program developed by USGS was executed about long-term stream discharge data to assess groundwater recharge on the 17 watersheds from 2000 to 2010. The average annual base flow on the watersheds were 0.67~295.46 m³/sec and areal weighted mean was 43 m³/sec, which was equivalent to 1.34 billion m³/yr.

Infiltration tests were carried out at 95 points in Geum river basin using Guelph permeameter and soil permeability were evaluated spatially. Field hydraulic conductivities are 6.00X 10^-6 ~ 2.91 X10^-2 cm/s, 4.73X 10^-3 cm/s in arithmetic mean, and 1.57X10^-3 cm/s in geometric mean. The permeability is high in KK-01, KK-04, KK-12, KK-14 watersheds, which are relatively high elevated areas, and low in KK-02, KK-03, KK-07, KK-08, KK-10, KK-15, KK-16 watersheds.

Groundwater resources were evaluated according to climate change and land use change in Geum river basin through groundwater flow modeling with WetSpass and updated modeling tool. Rainfall and groundwater recharge will be highly variable for 100 years, and big amplitude of groundwater level change will be expected in Gongju and Mhocheon watersheds.
Assessment of groundwater contamination vulnerability considering land use change in the future was performed using Logistic regression method. The vulnerability assessments were tested to the year 2050 and 2100, and groundwater contamination were highly correlated to land uses.
Groundwater resource change were evaluated in Jeju Island according to sea level rise through modeling works. Highly permeable layers play important roles to transmit seawater into inland, and groundwater inflow and outflow with salt water could be evaluated qualitatively and quantitatively.

Also, biological reaction to contaminant (heavy metals) was studied and environmental ecological evaluation method was established. Long-term monitoring of water quality in an alluvial aquifer was carried out to evaluate how surface contaminants infiltrate into groundwater system, and the results showed that vertical change and seasonal change in water quality was determined by geological conditions.

Finally, a GIS DB on groundwater resource vulnerability according to climate change and land use change were built, and it includes the groundwater occurrences, historic and future prospective climate change and groundwater budget, contamination vulnerability, spatial thematic maps such as soil and geological maps.
Artificial recharge has been proposed to be the most promising method to solve the shortage in water resource brought about by climate change. There are two systems for water curtain cultivation systems for aquifer recharge: groundwater recirculation water curtain cultivation system and rainwater collection and injection system. Groundwater recirculation water curtain cultivation system is used for heating greenhouses from late Fall to early Spring. Spent groundwater is not directly sent to aqueduct. Instead, it is sent back to aquifer in a nearby injection well to prevent depletion of groundwater resource, and to make continuous water curtain cultivation possible. Precipitation on the ceilings of greenhouses during the rainy season is collected in rainwater collection and injection system, and injected into the groundwater system to recover groundwater level that was lowered due to water curtain cultivation in the winter. Rainwater collection and injection system is an appropriate method for recent situation in which natural recharge gradually decreases due to more frequent heavy rainfall for a short duration. This kind of precipitation pattern was known to be caused by global warming.

A pilot-scale test site was established in Wangjeon-ri, Gwangseok-myun, Nonsan, Chungnam to study water curtain cultivation system for artificial aquifer recharge. The site covers the area of 1.2 km² excluding road, and approximately 30% (0.35 km²) of the site was used for water curtain cultivation. In the Wangjeon-ri area, 420 m³/day/ha of groundwater is using for water curtain cultivation system estimated by monitoring data of groundwater level and streamwater level. This amount of groundwater for water curtain cultivation system is corresponding to 40% of total agricultural use under the assumption of 5 month's operation period of all nationwide water curtain cultivation system.

There are total 6 wells including two pumping wells, two injection wells, and two observation wells. Each pumping, injection, observation wells have one alluvial well and one fractured aquifer well. Overall protected cultivation system using groundwater curtain with geological circulation and rainwater harvesting consist of pumping system, water curtain system, collection system, injection system, operation system, water treatment system, and monitoring system. To evaluate the hydrogeochemical characteristics, pumping tests, tracer tests with conservative tracer, dye tracer and thermal tracer, geophysical logging, water quality analysis are performed characterizing transmissive part in this area, groundwater velocity, source for groundwater quality problem. As a result of various tests, hydraulic conductivity of 3.47 x10^-6 m/s in fractured aquifer and 1.62 x10^-6 m/s in alluvial aquifer, storativity of 4.52X10^-4 in fractured aquifer and 0.15 in alluvial aquifer was estimated. Sustainable yield was estimated to be 18.51 m³/d from step drawdown test. Analysis of tracer tests estimates effective porosity of 0.105，average linear velocity of 2.68 x 10^-3 m/s and longitudinal dispersivity of 0.8 m. Transmissive fractured zone reveals to be 15-25 m below surface which is corresponding to a weathered fracture zones based on thermal tracer test and geophysical logging. The thermal tracer test using cool water reveals that the collected from greenhouse roof and injected cool water temperature is recoverd to ambient groundwater temperature when it arrives at pumping well which means that the aquifer circulating water curtain cultivation system is effective to provide warming temperature to greenhouse during winter time without dewatering aquifer.

A preliminary operation of the pilot system during the hot season using hot condition instead of cold condition resulted in the fact that geological circulating water curtain cultivation system is better than non-circulating system in terms of groundwater level, pumping rate, groundwater temperature recovery efficiency. During the practical operation during winter time in 2010, 6,100 m³/yr of groundwater reinjected to the aquifer and if this kind of facility is expanded to the whole greenhouse in the test basin, it will be 0.66 million m³/yr of water can be recharged. Let us assume that at least 50% of rainwater is collected and injected to injection well through the system, then 4,750 m³ of water can be estimated to inject into one injection well for a year.

Geothermal modeling was performed to study temperature recovery characteristics from pumping and injection in water curtain cultivation system for artificial aquifer recharge. Appropriate hydrological and geothermal parameters were applied to FEFLOW software to numerically model changes in pumping temperature with changing distance between pumping and injection wells, and effect of pumping temperature on overall system. Appropriate assumptions were made on the depth of aquifer, and hydrological and thermal variables. The system was modeled at distances of 15, 30, and 50 m. Thermal interference was not observed at the distance of 50 m, and thermal content of the system after 2 year operation was found to be at least 134 kW.

Radon and Fe/Mn removal system in groundwater that works without external power supply was developed to be used in small villages that use small scale water supply facility to utilize groundwater for daily use. The system is installed between induction pipe from groundwater well and storage tank. The water falling from the pipe collides with water turbine in the unit to remove Radon through aeration effect and to spin the turbine to emit Radon through the ventilation system at the top of the unit. When radon concentration is very high, the power supply equipment at the end of rotation axis of water turbine is connected to power generator to produce electricity. The electricity generated was used for the operation of aeration equipment, which was used to remove radon inside storage tank. The removal efficiency up to 80% was achieved with our test unit.

Subsurface geologic structure was investigated using geologic logs and geophysical exploration to establish geologic and hydrogeologic model of the area. Resistivity survey revealed that upper aquifers had highly fluctuated flow system. CO₂ sources in high-mineral water and CO₂-rich water was estimated as magmatic CO₂ using ¹³C and ¹⁴C. Negligible ³H in high-mineral water indicated that deep CO₂ is effectively isolated by low-permeable layers. Additional sources other than soil zone can enhance water-rock interactions resulting in higher mineral contents in groundwater. To assess proper yield of high-mineral water and high bicarbonate containing groundwater, step-draw down test was performed with monitoring of hydrogeochemical parameters at 7 wells. During the pumping test, CO₂-rich waters show little variations implying higher chemical stability of groundwater. However, those wells have significant seasonal variation of many chemical parameters suggesting it may be necessary to control infiltration of recharge water. Under an allowable drawdown of 30 m, the sustainable yield was estimated to be 970 m³/d in average, 281 m³/d in minimum，3,085 m³/d in maximum, and 551 m³/d in median, which shows that there are high variance in sustainable yield of wells due to high heterogeneity of geological formation.

(출처 : SUMMARY 11p)

목차 Contents

• 표지 ... 1
• 제출문 ... 2
• 최종(연차)보고서 요약서 ... 3
• 요약문 ... 4
• SUMMARY ... 11
• Contents ... 15
• 목차 ... 17
• 제1장 연구개발과제의 개요 ... 19
• 제1절 연구 배경 및 필요성 ... 21
• 제2절 연구 목적 ... 30
• 제3절 연구 범위 ... 36
• 제2장 국내외 기술개발 현황 ... 43
• 제1절 선행기술 조사 ... 45
• 제2절 선행연구사업 수행 현황 ... 49
• 제3장 연구개발 수행내용 및 결과 ... 53
• 제1절 기후변화에 따른 지하수자원 취약성평가 및 변동 예측 모델 개발 ... 55
• 1. 금강수계 지하수자원 취약성 평가 연구 ... 55
• 2. 수계규모 지하수 오염취약성 평가 ... 83
• 3. 기후변화에 따른 금강수계 지하수 유동 변화 모델링 ... 115
• 4. 기후변화 시나리오에 따른 지하수함양 영향 평가 연구 ... 156
• 5. 오염물질 침투에 따른 지하수환경의 환경생태학적 취약성 평가 ... 173
• 6. 기후변화에 따른 지하수 수질 변동 특성 평가 ... 210
• 7. 해안대수층의 해수면 상승에 따른 지하수 자원변화 모델링 ... 243
• 제2절 인공함양 적용지 선정 및 파일럿 규모 인공 함양 시스템 구축 ... 254
• 1. 인공함양 적용지역 특성화 연구 ... 254
• 2. 인공함양 시스템 구축 및 적용 연구 ... 323
• 3. 지하수 수처리 기술 개발 ... 390
• 4. 산화처리기법을 이용한 수막재배 지하수내 철 제거기술 개발 ... 418
• 제3절 고부가 제주도 지하수(탄산수) 생성/순환기작 규명 및 개발가능지 확보 ... 439
• 1. 지질 검층자료 및 전기 탐사를 이용한 지하 지질 분포 분석 ... 439
• 2. 고미네랄수/탄산수 산출지역 수리지구화학 조사 ... 453
• 3. 물리검층을 이용한 대수층 특성 조사 : 시험 시추공에 대한 공극률 추정 ... 465
• 4. 고미네랄 지하수 개발가능량 평가 ... 469
• 제4장 목표달성도 및 관련분야에의 기여도 ... 493
• 제1절 목표 달성도 ... 495
• 1. 최종 연구목표의 달성도 ... 495
• 2. 연도별 목표 달성도 ... 496
• 제2절 관련분야에의 기여도 ... 505
• 제5장 연구개발결과의 활용계획 ... 507
• 제6장 연구개발과정에서 수집한 해외과학기술정보 ... 511
• 제1절 최근 지하수 분야 연구/기술 동향 ... 513
• 제2절 기후변화 및 지하수 분야 전문연구정보 ... 515
• 제3절 인공함양 기술 연구 동향 ... 522
• 제7장 참고문헌 ... 533
• 끝페이지 ... 553