Is the Remediation at Parys Mountain Successfully Reducing Acid Mine Drainage?

• 作者: Niall Marsay
• 来源期刊: 环境保护(英文)
• 学科: 医学
• 关键词: ACID MINE Drainage REMEDIATION Parys MOUNTAIN Anglesey
• 年，卷（期）: 2018,（5）
• 页码范围: 540-553
• 页数: 14页
• 分类号: R73

摘要

Metal ion concentrations and acidity were used as indicators of acid mine drainage (AMD) at Parys Mountain, a large abandoned copper mine on An-glesey, Wales. Water samples were collected in two sessions and taken from a linear stream flowing from the northern side of the mine, and a stream flowing from the south side of the mine that has two settling ponds and long stretches of wetland along its path. pH measurements were taken to measure acidity levels and metal ions (Fe, Al, Zn, Cu, Mn, and Pb) were quantified by inductively coupled plasma (ICP-OES) spectrometry. The pH values at the settling ponds and northern stream were between 2 and 3 while the wetlands had pH values of 5 - 6 implying that it was the wetlands that reduced acidity, and not the distance downstream. Both streams showed a reduction in concentrations of all elements with distance downstream. The decrease was linear for the northern stream and exponential for the southern stream, suggesting that the reed beds and settling ponds were successful at removing metal ions;potentially, through slower flow rates allowing more time for redox reactions to occur, thus precipitating metal hydroxides and pure metals and removing them from solution. In November, the northern stream had substantially higher concentrations of Fe, Al, Zn, Cu, and Mn, but not Pb (126, 34.0, 29.1, 14.6, 10.4, and 0.064 mg/L respectively) in solution when compared to the southern stream, which had concentrations of 10.2, 12.2, 11.9, 2.43, 6.11, and 0.706 mg/L for Fe, Al, Zn, Cu, Mn, and Pb respectively. However, in January the first sample site had higher concentrations of all elements except Mn;(107, 22.0, 26.1, 10.3, 1.48, and 0.506 mg/L for Fe, Al, Zn, Cu, Mn, and Pb respectively) when compared to the northern stream (55.0, 10.6, 7.55, 6.10, 1.59, and 0.041 mg/L for Fe, Al, Zn, Cu, Mn, and Pb respectively): but by the second sample site, the southern stream concentrations had dropped to concentrations present in the northern stream. This data indicates less AMD was produced on t