Data from the nation’s mining regulators provided to Reuters revealed production during the third quarter was 21 million tonnes, 8% lower than the same period of 2011.
Compared with the second quarter of this year, total output from mines was down almost 19%.
Colombia’s second-largest coal exporter the US-based Drummond realized only a 1.7% increase in its year-on-year production to about 6Mt. Output compared to the second quarter showed a decrease of 8.5%.
Glencore, one of the companies hit hardest by the strike actions, had a 21% reduction in production from its mines.
A three-month-long strike at its La Jaguar operation, which produces the country’s highest quality coal, cut its output 92%.
Reuters noted the La Jaguar strike over pay and working conditions, which began July 19 and ended late last month, was one of the longest stoppages in recent history.
Both Drummond and Glencore’s Prodeco hold parts of the Fenoco railway, which also suffered a strike stoppage in July and August.
The Cerrejon complex, jointly owned by BHP Billiton, Anglo American and Xstrata, also had a production drop.
Between July and September, the country’s largest exporter recorded 8.7Mt, a 2% drop over the comparable 2011 quarter.
Tonnage versus the second period of this year fell approximately 7%.
Colombian mining officials already have said that production goals for 2012 have been cut to 93Mt from a prior target of 97mt; it had a combined 85.8Mt in 2011.
The South American country’s largest producers are Glencore, Drummond and Cerrejon. It is the world’s fourth-largest coal exporter.