Optimasi Sequence Penambangan dan Timbunan pada Three Month Rolling Plan untuk Mencapai Target Produksi di PIT E PT pada IDI

Abstract

Production shortages at PT Pada Idi's Pit E in January and February, caused by operational limitations, required an optimized short-term mining plan. This study applies a Three Month Rolling Plan (3MRP) for March–May to optimize the mining sequence and disposal design and meet production targets. Adjusted monthly goals were 51,449 MT coal and 436,622 BCM overburden (OB), with a target stripping ratio (SR) of 8.45. The technical mining sequence design met these targets, achieving 438,925.98 BCM OB and 53,558.83 MT coal with SR 8.20 in March, 448,803.77 BCM OB and 53,274.00 MT coal with SR 8.42 in April, and 452,443.05 BCM OB and 53,498.18 MT coal with SR 8.46 in May. Design-to-target variations ranged from 1–4%, with a cumulative average SR of 8.36 whereas safely below the company's 8.5 limit. A disposal strategy was also developed to manage loose waste. Since existing capacity at OPD X Utara and OPD EC 2 was insufficient, four new waste dumps IPD 1, OPD 1, OPD 2, and OPD 3 were designed within mined-out areas beyond the LOM Pit E boundary, adding 1,397,433.99 LCM. Combined disposal capacity reached 1,628,813.78 LCM, including a 1% safety buffer. Fleet capacity analysis and productivity forecasting confirmed the adjusted targets were achievable using 4 OB fleets and 1 coal fleet over the three months. Forecasted production exceeded sequence requirements by 3% in March with 450,163.04 BCM OB and 71,801.25 MT coal, 0.26% in April 449,963.9 BCM OB and 71,769.49 MT coal, and 4% in May with 470,581.07 BCM OB; 76,497.59 MT coal. These results satisfied all company indicators, validating the technical and operational feasibility of the proposed 3MRP in overcoming prior production delays.