About PT GBU


Technical Advisors

Bambang Setiawan

  • Master degree from the Institute Technology Bandung (ITB) in Mining Exploration Engineering
  • Ph.D Degree in Geology and Mining Exploration from The Ecole Nationale Superieure Des Mines de Paris, France
  • Formerly Director General of Mineral, Coal and Geothermal in the Ministry of Energy and Mineral Resoruces of the Republic of Indonesia.

Mathius Salempang

  • Former Deputy of Indonesian National Police in charge of Criminal Division (“Bareskrim”)
  • Former Head of Indonesian Police (“Kapolda”) for East Kalimantan and South Sulawesi.


Soebianto Hidayat
President Director

  • Over 20 years experience as owner and managing coal mine. Previously, owner and CEO of a coal mine in South Kalimantan.

Erwin Manurung
General Manager, Mine Technical & Planning

  • Bachelor degree from the Institute Technology Bandung (ITB) in mine engineering
  • 14 years experience in international mining companies across 3 countries: Australia, US and Indonesia (Freeport Indonesia, Energy Resource of Australia and others).
  • Specializes in mine planning and engineering, computerized mine design, pit optimization, geotechnical projects and evaluation.

Ganesan Veeraraghavan
General Manager, Mine Operation & Maintenance

  • Bachelor degree from PSG College of Technology in Electrical and Electronics Engineering
  • More than 20 years of experience in India and Indonesia covering procurement, logistic, production and plant maintenance division

Djaja Hartono
General Manager, Mine Operation Support

  • Bachelor degree in civil engineering
  • More than 10 years of real estate experiences, handling permits and licenses

Darma W. Nubary
General Manager, Finance

  • Master’s degree in from University of San Francisco majoring in Financial Economics
  • More than 10 years of progressive and direct finance experiences in financial management, investment & analysis across 3 industries and 2 countries (USA and Indonesia)

General Manager, Human Resources

  • Bachelor degree from Universitas Gajah Mada majoring in psychology
  • Over 8 years experience in oil, gas and mining
  • 10 years serving in Indonesia Navy, with last position as Navy Section Head