impenetrable

Meanwhile, at the WCS facility, the waste will be covered by a 40-foot-thick layer of impenetrable red clay —which serves the same function as the salt at WIPP—once the storage sites are filled.

When it comes to the increasing number of rape allegations leveled at Bill Cosby, the smoke is becoming impenetrable.

At the highest navigable point of the Congo River, thick jungle creates an impenetrable wall of green around a large island.

Together, they formed an almost impenetrable sea of fitted baseball caps surrounding the stage.

These reporters are working within a bubble, impenetrable to secular outsiders.

But, as Korda clearly recognizes, Lee himself could be almost as impenetrable as stone.

Now suddenly she felt a mystery in Baroudi far deeper, far more impenetrable, than any mystery that dwelt in Nigel.

The great horses with their eager riders dashed themselves in vain against the solid and impenetrable schiltron.

An endless forest, the impenetrable earth; the one to be removed, and the other to be excavated.

As they entered the mouth of the cave, darkness, black and impenetrable, dropped on them like a cloak.

And still that blank wall of dirt, that impenetrable darkness, that stubborn barrier between them and the blessed sunshine.