The top Environmental Protection Agency official in Montana said this week that the groundwater underneath East Helena probably will remain contaminated with arsenic and selenium forever.
The statement from Julie DalSoglio, the EPA’s Montana director, came during a friendly debate with Rob Collins, an assistant attorney general with the state Department of Justice’s Natural Resource Damage Program.
Collins is concerned that the $99 million settlement from the Asarco bankruptcy, which is being managed by the Montana Environmental Trust Group with oversight from the EPA, will run out before a water treatment plant can be created to address the contaminated groundwater, and Wednesday DalSoglio said that is a possibility.
“The state remains concerned the trust is spending so much money doing interim measures that will never be enough money to clean up the groundwater in East Helena,” Collins said. “I just think that everyone in the community ought to consider whether that’s something that should be looked into further or say that groundwater should be contaminated forever and we should just have institutional controls.”
Fix or contain?
DalSoglio said that at this point, they’re focusing on dealing with the source of the groundwater contamination, which is the soil at the old Asarco lead smelter plant site. But as they’re learning more about the extent of the contaminated materials, they’re coming to the realization that they probably will run short of money.
“We have to deal with the reality of the money we got,” DalSoglio said on Wednesday, during a meeting of the East Helena Entire Cleanup Team in Coordination, known as EHECTIC. “We are trying to reduce the amount of materials going into the groundwater and adding to the groundwater plume. We expect to see significant improvement in groundwater quality, but whether we can restore the entire aquifer plume to the state of Montana standards is a long shot.
“I think there will be long-term contamination and I hope the EPA has been clear on that.”
While that didn’t surprise Collins, he finds it disheartening. During Asarco’s bankruptcy litigation proceedings, state and federal officials discussed what needed to be done to clean up after more than 100 years of lead smelting. While that included removal of contaminants and capping of the site, it also involved a type of “pump-and-treat” system for the groundwater at a cost of around $50 million. Estimates put the length of treatment anywhere from 30 to 100 years or longer.
“Under our plan, you would extract the water around the boundaries of the smelter, take out the metals, then inject the clean water into the aquifer,” Collins said. “That would, in effect, spread out the arsenic and diffuse it so eventually it would reach drinking water standards.
“… My concern is that the way they’re spending their money there’s not going to be enough money left, so that will not be an option. Julie seems to say perhaps that’s right.”
Collins’ program was awarded $5 million under the bankruptcy settlement for natural resource restoration projects in East Helena and the Helena Valley, which could include wildlife habitat projects on the old plant site or establishing fishing sites along Prickly Pear Creek after the cleanup work is completed.
Actions to take
Betsy Burns, the EPA project manager for the East Helena site, said they may still install a pump-and-treat plant, but that might not be the best and most current technology to use. She also questioned the cost of the pump-and-treat system, noting that the estimates were done for litigation purposes and attorneys typically propose the most expensive remedy when seeking damages.
“Pump-and-treat is kind of old technology because it’s very expensive,” Burns said. “It’s just containment — they’re containing and capturing the waste, but not really addressing the source removal. As we move forward and do the corrective action study, it’s possible that other technology … will provide other long-term solutions that don’t have a lot of operations and maintenance connected with them.”
Both Asarco and the EPA have known for decades about the arsenic plume underneath the plant site, which was caused in part by arsenic-tainted processing water that was sprayed on buildings and the ground to keep the dust down. Rain and snowmelt helped the arsenic percolate down into the groundwater, where at one point the arsenic level reached about 65,000 times the federal drinking water standard.
Asarco installed monitoring wells on the plant site in the 1980s, as well as across Highway 12. The arsenic didn’t show much movement until around 2001, when elevated arsenic levels started to show up in the groundwater underneath East Helena. The arsenic plume rapidly grew but now appears to have stabilized after the plant was closed 12 years ago. The arsenic plume is known as “the mitten,” based on its shape, and now extends from the plant to shortly beyond East Helena’s northwest city limits.
Two selenium plumes were discovered in 2006, almost by accident, after an EPA scientist decided to test water samples for a wider range of contaminants than were done previously. The source of the selenium plumes is unknown, but they seem to parallel the arsenic plume yet stretch much farther into the Helena Valley and are now north of Canyon Ferry Road. The source of the selenium plume remains under investigation, but one appears to originate from underneath the slag pile.
Arsenic is a know carcinogen. Some selenium is needed for muscle and enzyme functions, but at higher levels it can cause deformed fingernails that might slough off, brittle hair or hair loss.
Low levels of naturally occurring arsenic and selenium have been found in Montana.
Burns agreed with DalSoglio that it’s “not a real possibility, it’s a reality” that the aquifer will remain contaminated under East Helena for a long, long time. She said that’s why measures are in place, like mandatory hookups to the East Helena community water system, and more are being considered. A groundwater control area also is possible, and ongoing monitoring of residential and monitoring wells is taking place.
“Like many communities, we’re instituting Institutional Controls to make sure there’s no risk to human health or ecological risk,” Burns said. “We know that source material has moved off site in the groundwater, particularly arsenic, and it exists under East Helena.”
She noted that the arsenic plume would have to move a significant distance in order to reach residential wells in the Helena Valley, and the work they’re doing by cleaning up and capping the plant site appears to be helping to slow the flow.
Both Upper and Lower lakes, generally southeast of the main plant site, were created by Asarco. The Upper Lake held clean water that was used to cool ore during the smelting process, and Asarco returned the water — contaminated with high levels of arsenic and other heavy metals — to Lower Lake.
Lowering the water level in Upper Lake, which is up gradient of the plant site, has lowered the groundwater flows through the plant site, which has a temporary liner on top of most of it to keep rain and snow from seeping into the ground.
Draining the water from Lower Lake also should aid in limiting the groundwater flows, while allowing for the removal of contaminated soils from the bottom of the lake.
This summer they expect to remove the remaining buildings on the plant site — including the large ore storage facility — and next year cap it with an impermeable barrier to keep snowmelt and rain from pushing more contaminants into the groundwater.