Abstract
We examined the contamination of stream water and stream sediments by heavy metal elements with respect to distance from the abandoned Backun Au-Ag-Cu mine. High contents of heavy metals (Pb, Zn, Cu, Cd, Mn, and Fe) and aluminum in the waters connected with mining and associated deposits (dumps, tailings) reduce water quality. In the mining area, Ca and SO$_4$ are predominant cation and anion. The mining water is Ca-SO$_4$ type and is enriched in heavy metals resulted from the weathering of sulfide minerals. This mine drainage water is weakly acid or neutral (pH; 6.5-7.1) because of neutralizing effect by other alkali and alkaline earth elements. The effluent from the mine adit is also weakly acid or neutral, and contains elevated concentrations of most elements due to reactions with ore and gangue minerals in the deposit. The concentration of ions in the Backun mining water is high in the mine adit drainage water and steeply decreased award to down stream. Buffering process can be reasonably considered as a partial natural control of pollution, since the ion concentration becomes lower and the pH value becomes neutralized. In order to evaluate mobility and bioavailability of metals, sequential extraction was used for stream sediments into five operationally defined groups: exchangeable, bound to carbonates, bound to FeMn oxide, bound to organic matter, and residual. The residual fraction was the most abundant pool for Cu(2l-92%), Zn(28-89%) and Pb(23-94%). Almost sediments are low concentrated with Cd(2.7-52.8 mg/kg) than any other elements. But Cd dominate with non stable fraction (68-97%). Upper stream sediments are contaminated with Pb, and down area sediments are enriched with Zn. It is indicate high mobility of Zn and Cd.
백운 폐광산 주변에 방치된 폐석으로 인한 하천수 및 하상퇴적물의 중금속오염정도를 알아보고자 하였다. 광산활동과 관련되어 발생하는 주변 하천수의 Al 및 Pb, Zn, Cu, Cd, Mn, Fe 등의 중금속 및 기타 이온의 부화현상은 하천수의 TDS를 높이며 또한, 수질을 악화시키는 요인이 된다. 백운광산 주변의 하천수는 Ca와 SO$_4$가 주를 이루는 Ca-SO$_4$형을 보이며, 부분적으로 황화광물의 화학적 풍화로 인한 중금속부화현상을 보인다. 광산을 경유해서 흐르는 하천수는 알카리 및 알카리 토류원소에 의한 중화작용의 영향으로 pH는 6.S-7.1의 약산성내지 중성을 띤다 폐갱구로부터 홀러나오는 갱내수 또한 약산성 내지 중성을 띠며, 광산내의 광석과 맥석광물과의 화학적 풍화로 인해 높은 원소함량을 보인다. 백운 폐광산 주변의 하천수는 갱내수가 유입되는 지역에서 높은 농도를 보이다 하류로 갈수록 농도가 급격히 낮아진다. 이온농도가 낮아지고 pH가 중성을 띠는 것은 자연적으로 오염을 조정해주는 희석 및 침전, 흡착 등으로 인한 완충작용의 결과이다. 토양내에서 중금속의 이동성이나 생물학적 이용능력을 알아보기 위하여 단계별 추출법을 이용하여 하상퇴적물에서 Cd, Cu, Zn, Pb의 존재형태를 5가지 단계로 분류하였다: 이온교환형태, 탄산염형태, 철-망간 산화물형태, 유기물형태, 잔류상형태. 대부분의 퇴적물에서 Cu(21-92%) 및 Zn(28-89%), Pb(23-94%)는 잔류상형태가 우세하였으며, Cd는 퇴적물에서 다른 원소에 비해 낮은 농도(2.7-52.8 mg/kg)를 보여주었으나 대부분 불안정한 형태(68-97%)가 우세하였다. 상류 퇴적물에서는 폐석으로 인해 Pb의 농도가 높게 나타나며, 하류 퇴적물은 Zn이 높은 농도를 보여, Zn 과 불안정한 형태가 우세한 Cd이 이동성이 높은 원소임을 알 수 있었다.thing construction. The presentation coverages and relative difficulties of textbooks were, however, diverse. It is somewhat noticeable that, while fewer professors majoring in clothing construction participated in writing, generally more pages were allocated to clothing construction than other areas. While presentations on anthropometrics method, construction theory, draft theory, usage of sewing machine and fitting theory were insufficient most textbooks were dealing with drafting of basic slopers and sewing procedure, etc. Making-up techniques on the apparels items such as Korean traditional men's pants, pajamas, shirt vest skirt, pants, apron and Korean pouch were handled closely in each textbook.different from the one in the l980s worn by the demonstrators of popular movements and democratic movements, and it emerged as a new symbol with the characteristics of cultural movement like community consciousness and nature affiliation.
