Mitsui Mineral Development Engineering Co., Ltd.

Mitsui Mineral Development Engineering Co., Ltd., commonly known by the abbreviation MINDECO, is a Japanese engineering and consulting company headquartered in the Gate City Ohsaki West Tower in Shinagawa-ku, Tokyo. It is a majority-owned subsidiary of Mitsui Mining & Smelting Co., Ltd. (now Mitsui Mining & Smelting Co., Ltd., often referred to as Mitsui Metals), which holds 66.6% of its shares, while K&O Energy Group Inc. holds the remaining 33.4%. The company was established in June 1981 (Showa 56) with capital of 100 million yen, and its capital was later increased to 400 million yen. Its representative director and president is Mitsuyoshi Saito. MINDECO describes itself as a comprehensive consultant for underground resource development and soil (geological) environment. Its business spans the full life cycle of mineral resource projects — desk studies, field surveys, feasibility and commercialization evaluations, development, and mine closure — as well as geothermal development, including geothermal surveys and the drilling of production and reinjection wells. It is also active in hot-spring (onsen) development, applying geochemical and geophysical exploration techniques to locate hot-spring resources with high probability. In the environmental field, MINDECO conducts historical land-use surveys, preliminary and detailed soil and groundwater contamination investigations, remediation works, and measures to prevent the spread of contamination. It is a designated investigation organization under Japan's Soil Contamination Countermeasures Act (designated by the Minister of the Environment, registration 2003-3-3076). The company also manages abandoned and suspended mines and performs rock mass and ground surveys. In addition to its core consulting and drilling services, MINDECO offers advanced technologies such as drone aerial photography, the SQUITEM and Reflex Tracker systems, software sales, and video analysis technology, and it acts as a Japanese sales agent for certain of these products. The company operates from its Tokyo head office and an Iwami office in Oda City, Shimane Prefecture. It recruits new graduates and experienced professionals, primarily in geology, geophysics, drilling and civil engineering roles. MINDECO's history reaches back to 1964 (Showa 39), when the engineering division of Mitsui Mining & Smelting was separated as Sankin Kiko Co., Ltd. In 1970 it was renamed Mitsui Metal Engineering Co., Ltd., and the resource division of Mitsui Mining & Smelting was transferred into it to form a Resource Development Headquarters. In June 1981 that headquarters was spun off as Mitsui Mineral Development Engineering Co., Ltd., established in Nihonbashi Muromachi as a subsidiary of Mitsui Mining & Smelting with capital of 100 million yen. The head office moved to Oimachi, Shinagawa in 1989, and to its current Osaki location in 2000. The company acquired shares of Matsunaga Geosurvey Co., Ltd. in 1990, absorbed Iwami Mining Co., Ltd. in 2001 while increasing capital to 400 million yen and starting a zeolite business, and ended zeolite mining in 2020 due to ore depletion. In 2025 it transferred 33.4% of its shares to K&O Energy Group Inc.

MINDECO's origins lie within Mitsui Mining & Smelting Co., Ltd. (now Mitsui Mining & Smelting Co., Ltd., commonly Mitsui Metals). In 1964 (Showa 39), the company's engineering and fabrication division was separated and incorporated as Sankin Kiko Co., Ltd. In 1970 (Showa 45), Sankin Kiko was renamed Mitsui Metal Engineering Co., Ltd., and the resource division of Mitsui Mining & Smelting was split off and merged into it, establishing a Resource Development Headquarters. On that foundation, in June 1981 (Showa 56), the Resource Development Headquarters was spun off from Mitsui Metal Engineering Co., Ltd. and incorporated as Mitsui Mineral Development Engineering Co., Ltd. (MINDECO), a subsidiary of Mitsui Mining & Smelting, with capital of 100 million yen and offices in Nihonbashi Muromachi, Tokyo. The company relocated its head office to Oimachi, Shinagawa-ku in 1989 (Heisei 1). In 1990 (Heisei 2) it acquired shares of Matsunaga Geosurvey Co., Ltd. In 2000 (Heisei 12) the head office moved to its current location, Gate City Ohsaki West Tower at 1-11-1 Osaki, Shinagawa-ku. In 2001 (Heisei 13) MINDECO absorbed Iwami Mining Co., Ltd. through a merger, increased its capital to 400 million yen, and began a zeolite business. In 2020 (Reiwa 2), zeolite mining was terminated due to depletion of the ore. In 2025 (Reiwa 7), the company transferred 33.4% of its shares to K&O Energy Group Inc., leaving Mitsui Mining & Smelting with 66.6%. Throughout its history, MINDECO has applied geological, geophysical, geochemical and drilling technologies to mineral resource exploration and development, geothermal energy, hot-spring development, and environmental remediation. It holds registrations as a soil contamination designated investigation organization (Minister of the Environment, 2003-3-3076), a construction consultant (MLIT, Ken 03 No. 10845), a geological survey firm (MLIT, Shitsu 05 No. 742), a surveyor (MLIT, No. (2)-35438), and construction business licenses from the Tokyo Metropolitan Governor for civil engineering, tobi/civil engineering, well drilling, water supply facilities, and demolition work. Its staff includes doctoral degree holders, professional engineers, surveyors, architects, civil engineering works execution managers, geological survey engineers, pollution control managers, well drilling technicians, and soil contamination investigation technical managers.

• 2025

  Transferred 33.4% of shares to K&O Energy Group Inc.

• 2020

  Zeolite mining terminated due to ore depletion.

• 2001

  Absorbed Iwami Mining Co., Ltd. through merger; capital increased to 400 million yen; zeolite business started.

• 2000

  Head office relocated to Gate City Ohsaki West Tower, 1-11-1 Osaki, Shinagawa-ku, Tokyo.

• 1990

  Acquired shares of Matsunaga Geosurvey Co., Ltd.

• 1989

  Head office relocated to Oimachi, Shinagawa-ku, Tokyo.

• 1981

  Resource Development Headquarters spun off as Mitsui Mineral Development Engineering Co., Ltd. (MINDECO), established in Nihonbashi Muromachi with capital of 100 million yen.

• 1970

  Sankin Kiko renamed Mitsui Metal Engineering Co., Ltd.; resource division of Mitsui Mining & Smelting merged in to form Resource Development Headquarters.

• 1964

  Engineering and fabrication division of Mitsui Mining & Smelting separated and incorporated as Sankin Kiko Co., Ltd.

Comprehensive engineering consultancy for underground resource development and soil/geological environment, combining resource development and environmental remediation expertise.

• Mineral resource development consulting

  Desk studies, field surveys, commercialization evaluation surveys, development, and mine closure services.

• Geothermal development

  Geothermal surveys and drilling of production and reinjection wells.

• Hot-spring development

  Hot-spring exploration and drilling using geochemical and geophysical techniques.

• Environmental remediation

  Historical land-use surveys, preliminary and detailed contamination investigations, remediation works, and prevention of contamination spread.

• Abandoned/suspended mine management

  Management services for abandoned and suspended mines.

• Rock mass and ground surveys

  Rock mass surveys and ground surveys.

• Advanced technologies

  Drone aerial photography, SQUITEM, Reflex Tracker, software sales, and video analysis technology; Japanese sales agent for certain products.

1. 1MINDECO official website homepagemindeco.co.jp
2. 2Company Information - MINDECOmindeco.co.jp
3. 3What is a hot spring? - MINDECOmindeco.co.jp
4. 4Recruit Information - MINDECOmindeco.co.jp
5. 5Wikidata: Mitsui Mineral Development Engineering Co., Ltd. (Japan)wikidata.org