Estimasi Penyebaran Kualitas Batubara dengan Metoda Kriging 2 (dua) Dimensi di Daerah Sigalut (Ombilin III) PT. Bukit Asam (Persero) Tbk, Unit Pertambangan Ombilin (UPO)

PT. Bukit Asam (Persero) Tbk. Ombilin Mining Unit is one of mine who
is a Badan Usaha Milik Negara (BUMN), the exploitation of coal by underground
mining methods (Underground Mining). To reach this location can be reached by
road from the city of Padang - Solok - Sawahlunto which is about 90 km,
PT. BA-UPO ton of coal has a very good interest to buy more companies.
There are companies who need and buy coal producer PT. BA-UPO ton with
more calories than 6000 kcal / kg, and less than 0.8% sulfur. So we have to
determine the spread of the quality and distribution of coal quality in a block
model. Block model done by geostatistics approach using kriging method to
estimate the distribution of coal quality in the area Sigalut (Ombilin III)
Modeling and assessment based sources dimensional block model which is
divided into blocks of size 50x50 units which are appropriate to the size of mining
block in area. Variables used for coal and sulfur are the calories.
Kriging estimates the value of each level in each unit block model (grid)
based on the data that there is data on drill hole, so that each grid will have an
estimated value. Degree-level estimation using kriging method with a certain cut�off value in accordance with the requirements of the quality of the company to
buy coal producer PT. BA-UPO ton. Estimated number of blocks that can be
obtained with high grade block 3470, block 1567 for low grade.