article_snippet: But, using its own power, its was able bore through nearly 20 feet of concrete last month to break through a wall leading to the rescue pit's opening, and it is now ready to be extracted.
article_snippet: Bertha , which weighs around 2,000 tons, was able bore through nearly 20 feet of concrete last month to break through a wall leading to the rescue pit's opening .
highlights_snippet: Bertha was able to use Bertha own power to break through 20ft of concrete and make Bertha way to a pit opening .
  