270 jobs could be affected after the owner of Aberpergwm Colliery in the Neath Valley begins talks on whether to suspend activity.
American firm Walter Energy says the proposal is a "result of a challenging economic environment which continues to heavily impact the global coal industry".
The firm insists that during the consultation period most of the employees will remain at home on full pay.
However up to 100 employees may be required to continue working at the mine to continue development works within the upper drift.
Early indications are that if the firm proceeds with the outlined proposals only a small number of employees would be retained to keep the mine in a safe condition until operationsresume.
More top news
An inquest is to be held into the deaths of four family members who died when their car was involved in a crash near Aberystwyth in June.
Cold and windy with sunny spells and showers of rain and snow.
The charity says the increase is partly due to people calling for help sooner, instead of attempting to rescue themselves.