土畑鉱山跡
かつて多くの鉱山が栄えた和賀郡旧湯田町で最後の鉱山として銅鉱の生産が続けられました。 1900 年（明治 33 年）に地元村民 照井岩次郎が畑平で露頭を発見した後、小和澤鉱山経営者 福田久右衛門が金銀鉱の試掘を出願しますが、採算性に乏しく、程なくして休山しました。 1903 年（明治 36 年）に東京の実業家 濱本義顕らが湯川金山合名会社を設立し、湯川金山と称して搗鉱法及び青化法を用いた製錬を行います。 同時期に白土において探鉱を進めますが、有望な発見に至ることなく再び休山を迎えました。 第一次大戦に際して銅の需要が高騰する中、1915 年（大正 4 年）に高橋謙一郎が畑平において銅鉱床を発見し、土畑鉱山と改称して売鉱を行います。 この翌年に田中鉱業（後の糸平興産）が鉱山を買収して本格的な採掘を開始し、土畑は発展を迎えることとなりました。 1924 年（大正 13 年）には国内初の全泥浮遊選鉱場が建設され、後に上野々鉱床の開発や近隣鉱山の買収が進められます。 昭和中期の 1959 年（昭和 34 年）に年間出鉱量は 172,000 t を上回り、およそ 700 名の従業員が雇用されました。 隣接する湯川では温泉が湧出し、鉱員住宅や浴場、購買所、講堂、小学校などを備えた鉱山町が築かれ、従業員とその家族を含む 3,000 人ほどが生活を送りました。 1976 年（昭和 51 年）に資源の枯渇により閉山を迎えますが、その後も坑廃水処理とともに沈殿銅の採取が継続されます。 山腹には当時の選鉱場跡が今も残ります。
1976 年閉山
Tsuchihata Mine
In former Yuda Town, where many mines were operated in the past, the mine produced copper ore as the last one. Iwajiro Terui, a local villager, discovered an outcrop at Hatabira in 1900. Then Kyuemon Fukuda, a manager of Kowasawa Mine, applied for an exploration permit for gold and silver ores. However, the operations were unprofitable, and the mine was abandoned. Subsequently, Yoshiaki Hamamoto, a businessman in Tokyo, and others established Yugawa Gold Mine General Partnership in 1903, beginning extraction with the amalgamation process and the cyanide process. Although mineral exploration began at Shiratsuchi around the same time, the results were poor, and the mine was abandoned again. Then the First World War caused a rise in demand for copper. Under such circumstances, Ken-ichiro Takahashi discovered copper deposits at Hatabira in 1915 and began mining operations. The mine was renamed Tsuchihata Mine, and mined ore was sold to others. Tanaka Mining Co., Ltd., later Itohei Corporarion, acquired the mine and commenced full-scale mining operations the following year. A beneficiation plant with the all-sliming process was constructed in 1924, which became the first in the country. Later, the company newly developed ore deposits at Uenono and purchased nearby mines. As a result, the mine produced over 172,000 tonnes of crude ore and had about 700 employees in 1959. A mining town was built in Yugawa, where a spring wells up, and had a population of about 3,000 comprising employees and their families. The town had many welfare facilities, such as row houses for miners, company bathhouses, a lecture hall, an elementary school, and a shop. Although the mine closed due to depletion of resources in 1976, wastewater treatment and the recovery of cement copper have been continuing. The remains of the beneficiation plant still stand on the mountainside.
closure in 1976
岩手県和賀郡西和賀町
銅、金、銀、亜鉛
Nishi-Waga Town, Waga County, Iwate
copper, gold, silver, zinc
田中鉱業は土畑を操業する傍ら、近隣鉱山の買収を進めて 1921 年（大正 10 年）に鷲之巣鉱山を合併します。 昭和に入ると甲子鉱山、翁沢鉱山を買収し、土畑の支山として稼行しました。 土畑はその名称の由来となる畑平と白土の他、上野々の三鉱床から構成され、銅鉱の採掘とともに坑廃水からの沈殿銅の採取が行われました。 上野々は選鉱場が置かれた畑平の北およそ 2 km に位置し、選鉱場までの鉱石輸送を索道が担いましたが、 1966 年（昭和 41 年）にトラック輸送へ切り替えられます。 これに伴い、畑平には麓から選鉱場上部へと続く長さ 250 m 近くの送鉱円筒ベルトコンベアが設置されました。
Tanaka Mining Co. merged Washinosu Mine in 1921 and purchased Kacchi and Okinasawa mines at the middle of the 20th century. Then each of them operated as part of Tsuchihata Mine. Tsuchihata Mine had three groups of ore deposits, namely, Hatabira, Shiratsuchi, and Uenono, and produced cement copper from wastewater in addition to copper ore. Uenono is located about two kilometers north of the beneficiation plant at Hatabira, and the ore transportation from Uenono to the plant switched from aerial cableway to truck in 1966. Accordingly, the foot of Hatabira and the top of the plant connected by a pipe conveyor with a length of about 250 meters.
畑平地区
Hatabira area
© 国土地理院
At the time of 1976
© 国土地理院
At the time of 1987
© Google
The present state
