Mosaic (NYSE: MOS) says production at its Esterhazy potash operations in Saskatchewan remained uninterrupted after a mining-induced tremor struck a mined-out area of its K3 underground mine on Tuesday.
The event occurred at 7:04 a.m. CST on Nov. 3, about 6 km east-northeast of Esterhazy, according to Earthquakes Canada, which now lists its magnitude at 3.5. All employees were accounted for and safety inspections were completed, Mosaic said.
“Mining induced seismic activity in this area is common, and our facilities are engineered with seismic loading in mind,” Mosaic said. “While the recent event occurred far from current mining areas and presents no immediate safety concerns, we continue to advance our understanding of the geological properties of the K3 ore body and will work with external experts to review seismic activity.”
The incident comes as Mosaic grapples with geological challenges at Esterhazy that have already weighed on potash production. On Tuesday, the company reported lower-than-expected ore grades at Esterhazy and reduced its 2026 potash production forecast to 8.6 million tonnes from about 9 million, a cut of roughly 4.4%.
Seismic history
It’s not the first time the Esterhazy area experiences mining-related tremors.
A worker died in a fall of ground at K3 on Dec. 15, 2025. Mosaic temporarily halted mining and announced an investigation at the time.
Esterhazy Esterhazy is one of Mosaic’s key potash production centres, with a nameplate capacity of 7.8 million tonnes annually. Mining shifted to K3 in 2021, when underground operations at K1 and K2 closed. K3 supplies ore by conveyor to the K1 and K2 processing plants.
About 1,200 people work above and below ground at Esterhazy, according to Mosaic’s website.
Production pressures
Mosaic posted a third-quarter net loss of $72 million (C$100.8 million), or 23¢ per share, compared with net income of $411 million, or $1.29 per share, a year earlier. Revenue fell about 10% to $3.1 billion.
Potash sales declined to $643 million from $695 million as volumes slipped to 2.1 million tonnes from 2.3 million tonnes.
The company attributed lower potash output to ore grades at Esterhazy and routine maintenance shutdowns at Colonsay and Belle Plaine. It expects grades to improve over time.
Muriate of potash cash production costs fell to $73 per tonne from $84 in the second quarter, although they remained above the year-earlier $71. Higher operating rates at Esterhazy and Colonsay improved fixed-cost absorption.
Mosaic is forecasting fourth-quarter potash sales of 2.3 million to 2.6 million tonnes. Realized mine-gate prices are projected to range between $255 and $275 per tonne.
Source: www.northernminer.com — article syndicated from the publisher’s feed; all rights remain with the original publisher.
