Ice thickness at Sam Charley Slough - Mid No flash player has been set up. Please select a player to play Flash videos. Video not playing? Update your browser or download the video clip Chas Jones discusses drilling the ice at this study site to measure the ice thickness. Process Observed: Open WaterGroundwater Upwelling Date Process Observed: Saturday, March 31, 2012 Galleries: Sam Charley Slough - Mid Gallery