The tanks are covered at the bottom with a thick, brown sludge, which engineers say they can handle.

A wave rolled in at them, bringing the uncomfortable brown sludge to their waists.

I slipped on the brown sludge that dripped through holes in the mesh, barely kept my balance.

The visor saved her eyes, but the brown sludge was opaque on the outer surface.

Dead fish floated in a slimy brown sludge on the surface, but Mom's attention was on me.

It smashed on the concrete floor, and brown sludge spattered up.

But he felt only his skin and the slimy splotches of brown, disgusting sludge.

A spoonful of brown sludge that it had filtered from the water glopped out.

At their feet slow currents moved around islands of brown sludge.

Some have even been known to be covered in a sort of brown sludge which resembles refried beans.