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Undang-Undang Nomor 32 Tahun 2009 mewajibkan setiap perusahaan pertambangan di Indonesia untuk melakukan kegiatan perlindungan dan pengelolaan pada lingkungan hidup. Salah satunya adalah kegiatan perlindungan dan pengelolaan terhadap pencemaran airtanah akibat aktivitas pertambangan. Analisis tingkat kerentanan airtanah bertujuan untuk mengetahui zonasi batas atau tingkat ketahanan airtanah terhadap suatu pencemaran di lokasi rencana kegiatan pertambangan. Tingkat kerentanan air tanah tersebut digunakan sebagai acuan untuk menentukan lokasi sarana dan prasarana pertambangan. Metode yang digunakan dalam penelitian ini adalah metode DRASTIC. Parameter kerentanan yang digunakan dalam metode tersebut adalah kedalamanan airtanah dari permukaan (Depth to groundwater), curah hujan (Recharge), media akifer (Aquifer media), jenis tanah (Soil), Topografi, pengaruh media pada zona tak jenuh air (Impact of vadoze zone) dan konduktifitas hidrolik (Conductivity). Metode DRASTIC membagi masing-masing parameter menjadi beberapa kelas menurut rating, dan membobotkan tiap parameter tersebut berdasarkan pengaruhnya terhadap kerentanan airtanah. Hasil akhir dari penelitian ini adalah peta kerentanan airtanah dengan nilai indeks berkisar antara 82 (rendah) sampai 165 (tinggi). Dari peta tersebut dapat disimpulkan bahwa daerah yang paling rentan terletak disebelah utara lokasi penelitian, sehingga kegiatan perlindungan dan pengelolaan dapat difokuskan didaerah tersebut.

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Material properties is one of the most significant variables in terms of efficiency. The sediment layer in a coal pit mine has a possibility of sticking to the equipment bucket and reducing its productivity, especially in the disposal area. Consequently, stickiness has a close definition of adhesivity level; thus it may be associated with geomechanical properties. Various soil classification in the disposal area was investigated to identify the relationship between adhesivity and geomechanical properties such as water content, density, cohesion, and internal friction angles. Multivariate regression analysis and statistical test (F-test and t-test) were used to investigate geomechanical properties related to adhesivity on each disposal area. Primary data was taken from a standard and modified laboratory testing. The results showed that disposal materials were high-plasticity materials with different grain-sizes. The dominant grain size on disposal 1, 2, and 3 were clay, sand, and clay, respectively. Based on regression analysis, the adhesivity on each disposal was increased along with the water content until its optimum value. Using a statistical test with a significance level of 95% (P-value 0.04), water content, cohesion and internal friction angle affected the adhesivity level on disposal 1 by 99% (adjusted R 2 0.99). Adhesivity level in disposal 2 was only affected with density by 63% (adjusted R 2 0.63). Meanwhile, in disposal 3, the significance level of 33% (P-value 0.50) was used to define that water content, cohesion, and internal friction angle as parameters affecting adhesivity level by 33% (adjusted R 2 0.33).

Acid mine drainage is an environmental issue impairing water sources globally. Efficient and continuous treatment in mining regions is urgently required. Therefore, this research aimed to evaluate the use of claystone from coal overburden, zeolite, and activated carbon from coconut shell as a composite to remove Fe and Mn from acid mine drainage. XRD, BET, and SEM characterized the adsorbent. The X-Ray Diffraction analysis showed the types of mineral in claystone were kaolinite, zeolite: mordenite, and activated carbon: cristobalite. Composite made with three ratios (Claystone:Zeolite:Activated carbon) = 50:25:25; 25:25:50; and 25:50:25. According to the surface area analyzer, composite with  a 25:25:50 ratio had the largest surface area (62,44 m2/g). SEM-EDX analysis showed that composite had porous morphology and active sites such as Al and Si. Adsorption was carried out using a hot plate stirrer with various contact time: 30,60,90,120 and 150 minutes. The results showed that composite succeeded in increasing  pH from 2.6 to 7.0 and reducing  Fe concentration from 13.006 to 0.1484 ppm (98,86%) and Mn concentration from 30.59 to 20.283 ppm (33,69%).  The adsorption capacities of the composite were 1,286 mg/g for Fe and 1,031 mg/g for Mn. It can be concluded that composite is a good adsorbent for removing iron from acid mine drainage.

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