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2017 Vol.27, Issue 3 Preview Page

Research Article

Optimal Pumping Rate of a Water Well at Imgokri, Sangju City

상주시 임곡리 굴착공의 적정양수량 결정

Byong-Wook Cho1
,
Uk Yun1*
,
Sang-Ho Moon1
,
Byeong-Dae Lee1
,
Soo-Young Cho1
,
YongCheol Kim1
,
Seho Hwang1
,
Jehyun Shin1
,
Kyoochul Ha1
조 병욱1
,
윤 욱1*
,
문 상호1
,
이 병대1
,
조 수영1
,
김 용철1
,
황 세호1
,
신 제현1
,
하 규철1
1Groundwater Ecohydrology Research Center, KIGAM
1한국지질자원연구원 지하수생태연구센터
* 교신저자* Corresponding Author
September 2017. pp. 255-265
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Abstract

We have determined the optimal pumping rate of the PW-2 water well (depth=100 m) at Imgokri, Sangju City. Cutting analysis and geophysical logging data reveal water-producing horizons at 26.1-26.5, 28.0-30.0, 33, 58, and 71 m. For pumping rates of 40, 55, 70, 90, and 132 m3/d over 70 days, the estimated drawdown from the PW-2 well was 6.48, 11.56, 18.07, 28.99 and 60.26 m, respectively. During a constant-rate pumping test at a rate of 117 3/d, the cone of depression intersected an impermeable bound­ary after 120-150 min of pumping. Therefore, we consider the critical pumping rate for well PW-2 to be 90 3/d. After pumping at 90 3/d for 70 days, the calculated drawdown was 28.82-31.27 m. We suggest an optimal pumping rate for well PW-2 of 70-90 m3/d, as the optimal pumping rate should be similar to the critical pumping rate. Sharp increases in the slope of the time-draw­down relationship, dissolved oxygen concentrations, and oxidation-reduction potential during the constant-rate pumping test indi­cate the limited development of bedrock aquifers around PW-2.

Keywords
Optimal pumping rate
Step-drawdown pumping test
Constant-rate pumping test
Drawdown
Impermeable boundary

상주시 임곡리에 굴착된 심도 100m 지하수공(PW-2)의 적정양수량을 산정하였다. 시추코아와, 물리검층 자료에 의하면 지하수 산출 심도는 26.1~26.5, 28.0~30.0, 33, 58, 71 m로 해석된다. 단계양수시험에 의하면 40, 55, 70, 90, 132 m3/d의 양수량으로 70일간 양수시 수위강하량은 각각 6.48, 11.56, 18.07, 28.99, 60.26 m로 예상되었다. 117 m3/d으로 250분간 실시한 일정량 양수시험에서는 양수 경과시간 120~150분에 영향추가 불투수층 경계조건에 도달하여 급격한 수위강하가 일어나 PW-2의 한계채수량은 90 m3/d로 산정하였으며 이때의 수위강하량은 28.82~31.27 m이다. 적정양수량은 한계채수량의 범위내의 정류상태여야 하기 때문에 PW-2의 적정양수량은 70~90 m3/d로 제시하였다. 불투수층 경계조건에서 직선의 기울기가 급해지며 지하수의 DO와 ORP가 증가하는 것으로 보아 PW-2를 중심으로 한 기반암지하수의 발달은 제한적인 것으로 추정된다.

키워드
적정양수량
단계양수시험
일정량양수시험
수위강하
불투수층 경계
References
1
Choi, H. M., Lee, J. Y., Cheon, J. Y., Jun, S. C., and Kwon, H. P., 2010, Estimation of optimal pumping rate, well effi­ciency and radius of influence using step-drawdown tests, Journal of Engineering Geology, 20(2), 127-136 (in Korean with English abstract).
2
Dawson, K. J. and Isotok, J. D., 1991, Aquifer testing: design and analysis of pumping and slug tests, Lewis Publishers, 344p.
3
Domenico P. A., 1972, Concepts and models in groundwater hydrology, McGraw-Hill, New York.
4
Freeze, R. A. and Cherry, J. A., 1979, Groundwater, Prentice-Hall, Inc. Englewood Clifffs, New Jersey 07632, 604p.
5
Gaona-Vizcayno, S., Gordillo, T., and Farvolden, R. N., 1985, Quality of water in an aquifer and its manifestation in pump­ing wells, Journal of Hydrology, 78, 165-181.
6
Hamm, S. Y., Lim, J. U., Bae, D. J., Chwae, U. C., 1998, A study on the determination of optimal yield from fissured aquifers, Journal of Korean Society of Groundwater Envi­ronment, 5(1), 21-29 (in Korean with English abstract).
7
Jha, M. K., Chikamori, K., Kamii, Y., Yamasaki, Y., 1999, Field investigation for sustainable groundwater utilization in the Konan Basin, Water Resources Management, 13, 443-470.
8
Jacob, C. E., 1947, Drawdown test to determine effective radius of artesian wells, Transaction of the American Society of Civil Engineers, 112, 1047-1064.
9
KIER, 1991, Geological survey report of the coalfields of Korea (Vol.13) : Poun coalfield (II) : Maro-Hwanam area, 89p (in Korean with English abstract).
10
KIGAM, 2016, Development of composite artificial recharge technologies for groundwater conservation and utilization, KIGAM report GP2015-014-2016(2), 329p (in Korean with English abstract).
11
Lee, J. Y., 2010, Problems in determining optimal discharge using step-drawdown tests, Journal of Geological Society of Korea, 46(5), 485-495 (in Korean with English abstract).
12
Lee, J. Y., 2016, Step-drawdown tests is not a tool to determine the so called optimal discharge rate, Journal of Geological Society of Korea, 52(4) 443-446 (in Korean with English abstract).
13
MOLIT, 2015, Guidelines of groundwater investigation, 344p.
14
Schafer, D. C., 1978, Casing storage can affect pumping test data, Johnson Drillers’ Journal, Jan/Feb, Johnson Division, UOP Inc., St. Paul, MN.
15
Theis, C. V., 1935, The relation between the lowering of pie­zometric surface and the rate and duration of discharge of a well using groundwater storage, Transaction of the Amer­ican Society of Geophysical Union, 16, 518-524.
16
USEPA, 1999, Proposed radon in drinking water rule, Office of Water, EPA 815-F-99-006. Yum, B. W. and Kim, H. C., 1997, Temperature log in Bore-holes, Journal of Korea Society of Groundwater Environ­ment, 4(2), 73-77 (in Korean with English abstract).
Information
  • Publisher :Korean Society of Engineering Geology
  • Publisher(Ko) :대한지질공학회
  • Journal Title :The Journal of Engineering Geology
  • Journal Title(Ko) :지질공학
  • Volume : 27
  • No :3
  • Pages :255-265
  • Received Date : 2017-08-03
  • Revised Date : 2017-08-13
  • Accepted Date : 2017-08-15
  • DOI :https://doi.org/10.9720/kseg.2017.3.255
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