IEG 환경지질연구정보센터

(1)

한국지하수토양환경학회 춘계학술발표회 2013년 4월 11일-12일 한화리조트 제주

Evaluation of groundwater chemistries in Korea’s different carbonate rock areas

Kabir Mohammad Lutful, Sang Woong Yun, Youngyun Park, Jin-Yong Lee

^*

Department of Geology, Kangwon National University

*

e-mail : [email protected]

Abstract

This study was conducted to understand chemical characteristics of groundwater in carbonate areas in Korea. In this study, the levels of pH, electric conductivity (EC), Ca

²⁺

, Mg

²⁺

, Na

⁺

, K

⁺

, Cl

^-

, SO

42-

and HCO

3-

were collected from 145 wells which were installed in various carbonate regions of Korea. pH ranged from 5.70 to 9.90 and the average was 7.20. The average value of EC was 388.5 μS/cm which were higher than that in granite and gneiss areas. Most of the groundwaters were Ca-HCO

3

type and some were Mg-HCO

3

type. The relationship between Ca

²⁺

and Mg

²⁺

with EC showed the positive trend with narrow range but the others had the positive trend with wide range. These results mean that sources of Ca

²⁺

and Mg

²⁺

were relatively simple such as carbonate dissolution compared with sources of the others. Na

⁺

, K

⁺

, Cl

^-

, SO

42-

and HCO

3-

might be supplied from not only water-rock interaction but also irrigation return flow and sewage because many wells had been developed for the supply of irrigation water. Especially, SO

42-

is known material released by fertilizer and pesticides applications. In this study, agricultural influence on groundwater was evaluated using cumulative plot of SO

42-

. The threshold value of SO

42-

calculated from the cumulative frequency curve was 35.1 mg/L. Therefore, 13.1% of total groundwaters were affected by agricultural activities. This research project was supported by the National Research Foundation of Korea (NRF) grant funded by the Korean government (MEST) (No. 2012-0002628).

IEG 환경지질연구정보센터

Evaluation of groundwater chemistries in Korea’s different carbonate rock areas

Kabir Mohammad Lutful, Sang Woong Yun, Youngyun Park, Jin-Yong Lee

Department of Geology, Kangwon National University

e-mail : [email protected]

Abstract

This study was conducted to understand chemical characteristics of groundwater in carbonate areas in Korea. In this study, the levels of pH, electric conductivity (EC), Ca

, Mg

, Na

, K

, Cl

, SO

and HCO

were collected from 145 wells which were installed in various carbonate regions of Korea. pH ranged from 5.70 to 9.90 and the average was 7.20. The average value of EC was 388.5 μS/cm which were higher than that in granite and gneiss areas. Most of the groundwaters were Ca-HCO

type and some were Mg-HCO

type. The relationship between Ca

and Mg

with EC showed the positive trend with narrow range but the others had the positive trend with wide range. These results mean that sources of Ca

and Mg

were relatively simple such as carbonate dissolution compared with sources of the others. Na

, K

, Cl

, SO

and HCO

might be supplied from not only water-rock interaction but also irrigation return flow and sewage because many wells had been developed for the supply of irrigation water. Especially, SO

is known material released by fertilizer and pesticides applications. In this study, agricultural influence on groundwater was evaluated using cumulative plot of SO

. The threshold value of SO

calculated from the cumulative frequency curve was 35.1 mg/L. Therefore, 13.1% of total groundwaters were affected by agricultural activities. This research project was supported by the National Research Foundation of Korea (NRF) grant funded by the Korean government (MEST) (No. 2012-0002628).

key words : Groundwater chemistry; carbonate dissolution: agricultural activity; cumulative frequency

curve; carbonate area