The black snow of Copșa Mică

Before sunrise, the queue at the gate smelled of sulphur and hot metal. On one side of the platform carbon black was made from methane gas, on the other ores were smelted for zinc and lead — and the blocks of flats, raised south of the works, stood right in the path of the stacks.

Carbosin had processed Transylvanian methane since 1935 and turned out carbon black for tyres and paints. With outdated equipment, it alone dumped more than one tonne of soot an hour on the town — 24 tonnes a day, every day. Its is the “black snow” the engineers of the 1990s entered into the records. It closed in 1993.

Sometra, opened in 1939, smelted concentrates for zinc and lead and had become the country's largest non-ferrous unit before 1990. Out of it came the lead, zinc and cadmium that entered the air, the water and the soil — the metals the soot hid from sight. In 1999 the majority stake went to Mytilineos; production stopped in January 2009.

The platform stands between the railway and the river, stretched east to west, and the town grew around it with no reckoning of the wind: two residential districts and the administrative zone lie right on the line the pollutants travel. The 250-metre dispersion stack appears in the 2006 permit file — the tallest thing the town ever raised.

In a school surgery with cold lino, the nurse ticked name after name: sample, blood pressure, height. The children of Copșa Mică were among the most measured children in Romania — and their figures, gathered by doctors from Cluj in three waves of studies, tell the same story from different angles.

The studies cannot be joined into one curve — they cover different ages, years and methods — but each is clear on its own slice. They are given separately, with ages and years beside them, as in the originals.

The workers paid first: 67 lead poisonings between 1968 and 1980, 1,247 between 1981 and 1989, 847 after 1990. The peak: 210 in a single year; by 1997 it was down to 66.

At the western edge of the platform stretches the dump: 19.2 hectares of mixed waste — furnace slag, ashes, sludges — gathered over 70-plus years of production, with no special lining. Any reckoning of what remains starts here.

The dump's figures come from the 2006 permit file: about 3,150,000 tonnes of material, of which furnace slag about 1,930,000 tonnes, on 192,308 square metres surveyed in 2004. By 2009 the company had invested over €20 million in equipment to abate the 1939–1990 pollution.

In May 2018 Sometra announced a €40 million plan: two new Waelz kilns to ecologically recycle the 3 million tonnes of slag in about 13 years of production, starting in 2020 — then turning the plant into a recycling-services provider. This page renders the plan as announced.

Meanwhile the 2016 fieldwork says what remains: the soil is still affected by the historical pollution, with frequent breaches of the intervention threshold — the worst point 700 metres south of the dumps, by DN14B. Groundwater stands much better, and the Vișa and Târnava Mare are in “very good” state. Today's sources: heavy traffic on DN14, up to 30,000 vehicles in 24 hours, and sporadic, much diminished Sometra activity.

• The dump3.15m t on 19.2 ha
• Invested by 2009over €20m
• The 2018 plan€40m, about 13 years
• Worst point, 2016700 m south of the dumps

On the bench stand six pairs of test tubes, each holding two genuinely measured values. Each round, pick the tube asked for — the peak year, the clean control, or the comparison line — and see at the end how you would have done as a lab hand at Copșa Mică.