Remediation of Acid Mine Drainage-Impacted Water

Abstract

The formation of acid mine drainage (AMD), a highly acidic and metal-rich solution, is the biggest environmental concern associated with coal and mineral mining. Once produced, AMD can severely impact the surrounding ecosystem due to its acidity, metal toxicity, sedimentation and other deleterious properties. Hence, implementations of effective post-mining management practices are necessary to control AMD pollution. Due to the existence of a number of federal and state regulations, it is necessary for private and government agencies to come up with various AMD treatment and/or control technologies. This review describes some of the widely used AMD remediation technologies in terms of their general working principles, advantages and shortcomings. AMD treatment technologies can be divided into two major categories, namely prevention and remediation. Prevention techniques mainly focus on inhibiting AMD formation reactions by controlling the source. Remediation techniques focus on the treatment of already produced AMD before their discharge into water bodies. Remediation technologies can be further divided into two broad categories: active and passive. Due to high cost and intensive labor requirements for maintenance of active treatment technologies, passive treatments are widely used all over the world. Besides the conventional passive treatment technologies such as constructed wetlands, anaerobic sulfate-reducing bioreactors, anoxic limestone drains, open limestone channels, limestone leach beds and slag leach beds, this paper also describes emerging passive treatment technologies such as phytoremediation. More intensive research is needed to develop an efficient and cost-effective AMD treatment technology, which can sustain persistent and long-term AMD load.

The Use of Low Grade Limestone in Acid Mine Drainage Treatment

“…Carbonic acid further reacted with hydrogen ion (H + ) to produce water and carbon dioxide gas. As a result, the use of H + can increase pH in AMD sample after the reaction [14]. 2.47 ± 0.01 6.44 ± 0.00 Table 3 shows the heavy metals content in AMD samples before and after reaction with LGL.…”

“…Precipitation is one of the separation techniques to reduce heavy metals content in AMD samples. Heavy metals such as iron or zinc can be precipitated as carbonate or hydroxide metals as shown in Equations 5 and 6, respectively [14].…”

Preliminary studies on potential remediation of acid mine drainage‐impacted soils by amendment with drinking‐water treatment residuals

“…Although Federal regulations such as the Surface Mining Control and Reclamation Act of 1977 have established a program for regulation of surface mining activities and reclamation of mined land, more than 557,000 abandoned mines exist in the United States, many of which are actively generating AMD (U.S. Forest Service, ). We discussed current AMD management practices with their pros and cons in one of our recent publications (RoyChowdhury, Sarkar, & Datta, ). Currently, there is considerable interest in developing a more affordable and efficient AMD remediation technology.…”

Heterotrophic Microbial Stimulation through Biosolids Addition for Enhanced Acid Mine Drainage Control

“…The USA is currently estimated to have more than 557,000 abandoned mines with approximately 15,000 to 23,000 km of streams impacted by AMD. The treatment of these AMD sites for protection of the US natural forest system is estimated to cost about US$4 billion [11][12][13][14][15][16][17]. Total cost estimates for remediating AMD-impacted sites in the USA and Canada combined runs into the tens of billions of dollars [11].…”