Abstract. PT Pancaran Surya Abadi is a company engaged in coal mining. PT Pancaran Surya Abadi is the holder of the Mining Authority (KP) obtained from the Government in the Decree of the Regent of Kutai Kertanegara with the Regional code Number: KW KTN 2010 676 OP, with an area of about 199.9 hectares. Location of Mining is located in Saopalai Village, Muara Badak District, Kutai Kartanegera Regency, East Kalimantan Province. Overburden stripping activities use a Komatsu PC-400 LC excavator dig-and-load tool and 4 Volvo A40F Articulated Dump Trucks, the age of the mechanical devices used has almost reached its service life limit, resulting in decreased performance of the equipment. This greatly affects the value of its productivity which will decrease further, as well as operating costs which continue to increase every year. So that mining activities are not disturbed by equipment problems, it is necessary to replace these tools. To plan the replacement of mechanical devices, it is necessary to conduct a technical and economic study. Technical studies covering equipment production studies, as well as economic studies covering operating costs, Present Worth Cost, and Unit Cost Production. The results of the technical and economic studies for the production of old digging equipment are 1,440,608.63 BCM / year, for new digging tools are 1,942,435.17 BCM / year. Meanwhile, production of old transportation equipment is 1,432,351.36 BCM / year, for new transportation equipment is 1,931,883.25 BCM / year. The results of the calculation of operating costs and Unit Cost Production of the old digging tool are Rp. 3,504,513,343.27 / year, for operating costs and Unit Cost Production of Rp. 2,411.17 / BCM, for operating costs of new digging tools Rp. 2,151. 545,359.27 / year and Unit Cost Production of Rp. 1,699.41 / BCM. Whereas for the old transportation equipment, the operating costs were Rp 2,323,670,282.50 / year and the Unit Cost Production was Rp. 8,018.19 / BCM for the new transportation equipment operating costs of Rp 1,803,047,942.50 / year and the Unit Cost Production was Rp 6,297. 94 / BCM. Based on technical and economic studies, the dig-load and conveyance tools need to be replaced because the productivity of the new tools is greater and the operating costs are more efficient than the old tools, from the results of the Unit Cost Production for new digging and transporting tools that are more efficient than the old tools, and long-term investment if buying a new tool.Keywords :  Device Life Productivity, Owning Cost, Operating Cost, Present Worth Cost (PWC), Unit Cost Production Abstrak.  PT Pancaran Surya Abadi merupakan perusahaan yang bergerak dibidang  penambangan batubara. PT Pancaran Surya Abadi merupakan  pemegang Kuasa Pertambangan (KP) yang diperoleh dari Pemerintah dalam Surat Keputusan Bupati KutaiKertanegara dengan  kode Wilayah Nomor : KW KTN 2010 676 OP, dengan luas wilayah sekitar 199,9 Hektar. Lokasi Penambangan terletak di Desa Saopalai, Kecamatan Muara Badak, Kabupaten Kutai Kartanegera, Provinsi Kalimantan Timur.  Kegiatan pengupasan overburden menggunakan alat gali-muat excavator Komatsu PC-400 LC dan 4 alat angkut Articulated Dump Truck  Volvo A40F, umur dari alat mekanis yang digunakan hampir mencapai batas umur pemakaiannya, sehingga mengakibatkan kinerja dari alat tersebut menurun. Hal ini sangat mempengaruhi nilai produktivitasnya yang akan semakin menurun, serta biaya operasi yang terus meningkat setiap tahunnya. Agar kegiatan penambangan tidak terganggu oleh masalah peralatan, maka perlu dilakukan penggantian terhadap alat-alat tersebut. Untuk merencanakan penggantian alat mekanis perlu dilakukan kajian secara teknis dan ekonomis. Kajian teknis yang meliputi kajian produksi alat, serta kajian ekonomi yang meliputi kajian biaya operasi, nilai Present Worth Cost, dan Unit Cost Production. Hasil dari kajian teknis dan ekonomis untuk produksi alat gali-muat lama sebesar 1.440.608,63 BCM/tahun, untuk alat gali-muat baru sebesar 1.942.435,17 BCM/tahun. Sedangkan untuk produksi alat angkut lama sebesar 1.432.351,36 BCM/tahun, untuk alat angkut baru sebesar 1.931.883,25  BCM/tahun. Untuk hasil perhitungan biaya operasi dan Unit Cost Production alat gali-muat lama sebesar Rp 3.504.513.343,27 /Tahun, untuk biaya operasi dan Unit Cost Production Rp2.411,17/BCM, untuk biaya operasi alat gali-muat baru Rp 2.151.545.359,27/Tahun dan Unit Cost Production sebesar Rp 1.699,41/BCM. Sedangkan untuk alat angkut lama biaya operasi sebesar Rp 2.323.670.282,50/ Tahun dan Unit Cost Production  sebesar Rp 8.018,19/BCM untuk biaya operasi alat angkut baru sebesar Rp  1.803.047.942,50/Tahun dan Unit Cost Production sebesar Rp 6.297,94/BCM. Berdasarkan kajian teknis dan ekonomis untuk alat gali-muat dan alat angkut perlu diganti karena produktivitas alat baru lebih besar dan biaya operasi lebih hemat dibandingkan alat lama, dari hasil Unit Cost Production untuk alat gali-muat dan angkut baru lebih hemat dibandingkan alat lama, serta investasi jangka panjang jika membeli alat baru.  Kata Kunci :      Umur Alat, Produktivitas, Biaya Operasi, Biaya Kepemilikan, Present Worth Cost (PWC), Unit Cost Production.