Gooding, Idaho ( KMVT-TV / KSVT-TV ) - A small vile of mercury that spilled onto the floor of the North Valley Academy school in Gooding is causing concern for the Idaho Department of Environmental Quality.

Feb 26, 2014 at 3:48 PM MST Update: Officials say they checked a total of 240 students following the Mercury spill at the school. They found 3 shoes that were contaminated. They say everything is cleaned up and that the students are free to leave.

Feb 26, 2014 at 2:48 PM MST Original Story Created: Albert Crawshaw, the Hazmat Waste Scientist officer for the Twin Falls District of the DEQ said they are in the “containment phase” at this time. Officials said one-ounce of Mercury was found spilled near a heater in the corner of the schools entry way. Crawshaw said that “This is a significant amount of a release”. The DEQ has set up an incident command unit for the assessment process. Currently they are evaluating up to 400 children for possible exposure.

Officials say they don’t know how the mercury got to the school. Crawshaw said he has been told it’s not part of the school’s lab. The spill was reported at 8:50 am this morning but the actual spill happened sometime yesterday.

The DEQ has asked the Public Health Department to be at the scene to answer questions. Merle Egbert, with the health department said they are waiting for the results of the tests to determine the amount of contamination.