BENTON COUNTY, WASHINGTON — Hundreds of workers were evacuated from one of the most radioactive sites in America on Tuesday, when a hole collapsed in a tunnel used to store nuclear waste. <br /> <br />The Hanford Site in Washington State covers an area of 586 square miles, which is about half the size of Rhode Island. <br /> <br />The collapse occurred in an area where two tunnels used to store radioactive materials join together, the Washington Post reported. The hole is around 20 feet long. <br /> <br />The tunnels hold contaminated train cars and highly radioactive waste. <br /> <br />Vibrations from nearby road work may have caused the tunnel to cave in, an unnamed source told NBC affiliate KING. <br /> <br />Emergency responders were using a robot to take video and survey the damage. <br /> <br />There was no initial indication that radiation had leaked from the area, according to Energy Department officials. <br /> <br />The last nuclear reactor to be shut down at the Hanford Site was decommissioned in 1987.
