WESTERLY — The mercury spilled from a container being handled by a custodian at Babcock Hall last week was about a quarter of an ounce, the amount that might be in a large-sized thermometer, according to John Leo, an emergency response official with the state Department of Environmental Management. An ounce of mercury weighs a little less than a pound.
Leo, who was called to the school district’s Highland Avenue school facility last Tuesday, said he advised administrators to evacuate the building as a precaution. Westerly Superintendent Roy M. Seitsinger Jr. had already done so after the custodian reported the mishap to administrators shortly after it happened at about 11 a.m. The woman had been clearing out cabinets in the basement cafeteria of the former middle school, which now houses administrative offices, high school classes and a day care center.
Seitsinger also contacted Robert Vanderslice, chief of the office of environmental health risk assessment with the state Department of Health, who was also called on to provide his expertise. The school was reopened after several hours. The day care center was closed for the day.
The worker carried the small container (described as the size of a Chiclets package) containing the mercury to the administration office, thereby creating a wider area of potential contamination. Seitsinger said the custodian had taken the container from an incorrectly labeled box, obviously not knowing its volatility when she brought it to the office, according to Leo.
Leo said the spill itself was minute, but it is the mercury vapor that is a health concern. Leo emphasized that this was a “very, very” minor incident. He said no one was exposed to a dangerous amount of mercury vapor for a significant amount of time. Mercury was commonly used in chemistry classes for many years, said Leo, indicating that the stored product could have been something left over from a class and put away, especially if the box was not marked correctly.
The federal Environmental Protection Agency stipulates that mercury vapor must be measured in parts per trillion. To do so the DEM uses a Lumex meter.
Leo said the EPA’s standard for a “level of concern” is anything above 300 parts per trillion.
In the area where the spill occurred there were readings of more than 1,000 parts per trillion, Leo said. In the bag containing the mercury, the readings were 3,000 to 4,000. Leo said he informed the superintendent that a special cleanup crew would have to be called to deal with the situation and was on its way.
The custodian was also exposed to high readings, with her shoes testing at over 1,000 parts per trillion. Leo said that although the contamination could have been removed with a lot of work, the decision was made to dispose of the shoes.
He said he told the woman to go home and wash her clothes and herself. (She was reported to have later gone to the Westerly Hospital for observation and was then released.)
Leo said the cleanup of the area was vigorous, involving ventilation and the use of a special vacuum to clear the area of any trace of mercury.
Leo said the office area where the custodian had brought the container read between 300 and 400 parts per trillion, enough to call for ventilation of the room using fans, and opening the windows to “let Mother Nature” take its course in letting the vapor dissipate.
Seitsinger said he initiated a schoolwide alert at about 2:30 p.m. to inform the students, staff and faculty of the incident. Later in the evening, at a time when he estimated that most families would be having dinner, Seitsinger sent out a call to parents through the district’s alert system. Some parents complained that they should have been informed earlier about a “hazardous chemical spill.”
Leo advised those with questions regarding disposal of mercury thermometers or other instruments to visit the DEM website for information.