CONVENT, La. (AP) - Officials with a company that owns an unstable phosphogypsum pile and a lake of acidic water atop it say they're encouraged by recent efforts to halt a potential environmental disaster in a Louisiana parish.

  

The Advocate reports unexpected movement along the pile's northern face has raised fears that it could fail catastrophically and release acidic water laced with heavy metals and trace radioactivity into swamps and waterways around the Uncle Sam plant near Convent.

  

Mosaic Fertilizer has been trying to drain the 140-acre lake and reduce pressure on the sliding wall of gypsum. It also brought in dirt to act as a kind of brake.

  

Mosaic says it doesn't have sufficient data to calculate the risk that a bulge in the pile wall will give away, but believes that it's falling.