Prediction of acid mine drainage generation potential of various lithologies using static tests: Etili coal mine (NW Turkey) as a case study

Abstract

The Etili neighborhood in Can County (northwestern Turkey) has large reserves of coal and has been the site of many small-to medium-scale mining operations since the 1980s. Some of these have ceased working while others continue to operate. Once activities cease, the mining facilities and fields are usually abandoned without rehabilitation. The most significant environmental problem is acid mine drainage (AMD). This study was carried out to determine the acid generation potential of various lithological units in the Etili coal mine using static test methods. Seventeen samples were selected from areas with high acidic water concentrations: from different alteration zones belonging to volcanic rocks, from sedimentary rocks, and from coals and mine wastes. Static tests (paste pH, standard acid-base accounting, and net acid generation tests) were performed on these samples. The consistency of the static test results showed that oxidation of sulfide minerals, especially pyrite-which is widely found not only in the alteration zones of volcanic rocks but also in the coals and mine wastes-is the main factor controlling the generation of AMD in this mine. Lack of carbonate minerals in the region also increases the occurrence of AMD.

Influence of Extremophiles on the Generation of Acid Mine Drainage at the Abandoned Pan de Azúcar Mine (Argentina)

“…In addition, the sulfur content was in the range between 2.51 and 13.1 wt% S. Table 3 shows the results obtained from the NAG test performed. NAG pH has been proposed as single indicator (or in combination with other static tests) of the potential of the samples to generate acidity; samples with NAG pH below 4.5 are potentially acid forming (PAF) [38][39][40]. This parameter is generally more appropriate since it is the result of the balance between the ability to produce acid and the neutralizing capacity of the rocks, while other parameters calculate the potential to generate acid from the sulfur content by overestimating that capacity since there are sulfur-containing minerals (including many sulfides) that are not acid-producing minerals.…”

Evolution of Acid Mine Drainage from a Coal Waste Rock Pile Reclaimed with a Simple Soil Cover

“…Figure 3a,b presents the particle size distribution and moisture retention curves, respectively, for the till material used in the cover and the waste rock material. Acid base accounting (ABA) tests are well established and widely accepted to characterize waste rock acidity [35,36]. ABA tests were performed on eight waste rock samples that were collected during drilling of the four CMT wells: One shallow and one deep sample were used from each CMT well.…”

“…The key remedial objective at the Lingan WRP was to attenuate the impact of AMD to the primary environmental receptors (groundwater and Graces Brook) over time. Acid base accounting (ABA) tests are well established and widely accepted to characterize waste rock acidity [35,36]. ABA tests were performed on eight waste rock samples that were collected during drilling of the four CMT wells: One shallow and one deep sample were used from each CMT well.…”

Static Test-Based Acid Rock Drainage Formation Potential of Metalliferous Tailings from O’Kiep, South Africa

“…The MTs samples used in this study were collected in acidic zones of the TSF which was confirmed by the paste pH (3.1) of the MTs, revealing the elevated acidity of the MTs. Low paste pH can be related to iron sulfide oxidation and also to soluble mineral dissolution [32]. The modified ABA test classified the MTs sample as having low sulphide-S content (6.1%) and highly negative values of NNP (-210 kg CaCO 3 /t) indication that the MTs are likely to generate ARD when exposed to atmospheric conditions [33].…”