Tennessee Valley Earth Partnership will be collecting mercury thermometers at the Maryville College Earth Round-Up event this year on Saturday, April 19 from 5 to 8 p.m. Exchange old mercury thermometers for a new, free digital thermometer. For safety, transport the thermometers in their storage cases. If the case is not available or the thermometer is broken, the thermometer can be brought in a 12-ounce plastic soda bottle with a screw-cap lid. If your thermometer contains a red liquid it is not a mercury thermometer, and can be disposed safely in your trash. Mercury-containing thermometers always have silver liquid.