Former Valea Jiului coal mine in closure, with surface structures awaiting demolition and site undergoing remediation.
Exploatarea Minieră Lonea is a hard coal (huila) mine located in the Lonea locality of Petrila city, Hunedoara County, in the eastern end of the Jiu Valley coalfield. The first extraction shaft in the Jieț area was sunk in 1873, and the mine entered active production in the following decade, operating almost without interruption for over 150 years. During the Communist era it reached peak capacity, with coal trains running on the Lonea–Petrila narrow-gauge railway at fifteen-minute intervals.
In 2016 the mine was formally designated non-competitive and entered a phased closure programme supported by European Commission state aid. Extraction was progressively reduced, and the workforce fell from around 4,500 in the Communist period to some 300–400 by the early 2020s. Closure works, including the sealing of the Puțul Valea Arsului shaft and associated ventilation raises, are planned to conclude by the end of 2026 or later.
Surface buildings are deteriorating, some already ruined, and the site faces full remediation.
Exploatarea Minieră Lonea lies at the eastern extremity of the Jiu Valley coalfield, in the Lonea locality which administratively forms part of the town of Petrila in Hunedoara County. The coalfield runs for over sixty kilometres from Lonea in the east to Valea de Brazi in the west, and Lonea's field was among the first in the valley to be opened.
The first extraction shaft in the Jieț zone was sunk in 1873, marking the beginning of systematic underground development on this part of the field. Active coal extraction began in the following years, and the mine operated through the late nineteenth and early twentieth centuries under the successive ownership structures that governed the Austro-Hungarian and then Romanian industrial economy of the region. In December 1918 the mines of the Jiu Valley were transferred into Romanian state administration.
During the Communist period Lonea reached its operational peak. Coal trains on the Lonea–Petrila industrial railway — a route of five to six kilometres — ran at fifteen-minute intervals carrying full wagons to the preparation facilities at Petrila and returning empty. The mine employed several thousand workers at its height, and the settlement of Lonea developed the characteristic miner colony character of the Jiu Valley, with workers' housing blocks constructed alongside the older colony dwellings.
In 1986 a separate entity, Întreprinderea Minieră Lonea Pilier, was established to exploit a coal reserve identified between Petrila and Lonea. This subsidiary enterprise closed in 1994, following the broader restructuring that began after the 1989 revolution. The main Lonea mine continued, though with a workforce that fell sharply through successive redundancy programmes in the 1990s and 2000s.
In 2016 the Romanian government formally included Exploatarea Minieră Lonea in a phased closure programme under the European Commission Decision 2010/787/EU on state aid for the closure of uncompetitive coal mines. The original closure target of 2018 was extended to 2021, then to 2024, and subsequently revised again to 2026 for the completion of safety works, closure operations, and site remediation. A study by Poland's Central Mining Institute recommended that controlled extraction continue for four to six additional years to manage the risks of spontaneous combustion and explosive gas accumulation inherent in the coal seams.
Closure works identified in the programme include the decommissioning and backfilling of the Puțul Valea Arsului and associated ventilation raises at the 840 metre level, the recovery of underground machinery, and measures against gas migration to surface. The mine's surface buildings, several already in an advanced state of decay, are subject to demolition as part of the remediation programme. The Lonea–Petrila industrial railway, which had carried coal for over a century, ceased operation in 2023. The workforce of approximately 300–400 in the mine's final years represents a fraction of the peak Communist-era employment.