Boulby Potash Mine (IMAGE) Penn State Caption Boulby potash, polyhalite and salt mine on the northeast coast of England is Great Britain's deepest mine and the home of the Science and Technology Facilities Council's Boulby Underground Laboratory. The mine, operated by ICL-UK/Cleveland Potash Ltd., is expected to be the site of the Advanced Instrumentation Testbed project, a new international multi-laboratory and university collaboration for nonproliferation research. The WATCHMAN detector would be placed in an excavated cavern at the Boulby site and is slated to become operational in approximately 2023. Credit Lawrence Livermore National Laboratory Usage Restrictions Image credit must be published alongside the image. License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.