NewsMontana News


EPA report details chemical plume underneath Butte High School, adjacent apartment building

Posted at 4:50 PM, Oct 08, 2021
and last updated 2021-10-08 20:17:55-04

BUTTE — Underneath the buildings on Butte's South Main Street, sits a toxic chemical plume.

First discovered 12 years ago, Montana DEQ had considered the plume a low risk even though the concentrations of toxins were above DEQ-7 groundwater standards. Over the years, DEQ had looked for ways to confirm the low-risk nature of the plume.

"When there were some changes in EPA’s guidance and an update to their hazard ranking system we then referred this site to EPA in order to take advantage of some federal resources for a further site evaluation or site assessment," said Kevin Stone, Montana DEQ Public Information Specialist.

toxic plume.gif
The EPA and DEQ say the main concern is if any of these toxic chemicals are coming up through the ground through vapors.

The EPA began a preliminary assessment in 2019. The assessment looked at historic data collected from the site.

"We found that there’s probable plume extending under the high school and the apartment building in the area. . . we decided that we need to have a further investigation which is what we should be doing this winter," said Joseph Chisholm, EPA Site Assessment manager.

The EPA and DEQ say the main concern is if any of these toxic chemicals are coming up through the ground through vapors.

The main toxic chemicals found are Trichloroethylene (TCE) and Tetrachloroethylene (PCE).

"In higher concentrations, the type of effects that you can see with these types of contaminants, you can see some neurological symptoms - and then there’s evidence of increased risk of cancers," said Charlie Partridge, U.S. EPA Toxicologist.

According to the CDC, children and adults may suffer:

  • Neurological effects- delayed reaction times, problems with short-term memory, visual perception, attention, and color vision
  • Neurobehavioral performance deficits- delayed recall and deficits in visual perception, decreased blink reflex, and mood effects (i.e., confusion, depression, and tension)

"Right now, we’re primarily focused on collecting data to make sure there are no long-term chronic health effects," said Patridge.

The EPA will begin testing the sites during the winter.

"It’s really important for the community to know that we’re working diligently to ensure the safety of all Butte citizens," said Dana Barnicoat, EPA Region 8 Community Coordinator.

The EPA will be holding a virtual community discussion next Thursday from 7-9 p.m. To join the listserve to receive the meeting link as well as updates, send a blank email to In the subject line write in: Join.