This story has been updated to include comments from the EPA.

The Environmental Protection Agency could loosen its requirement that an East St. Louis incinerator monitor its emissions for heavy metals that could be harmful to human health.

In Jan. 2017, the federal agency issued a draft air quality permit for Veolia Environmental Services’ incinerator in Sauget that required the facility to install “multi-metal monitoring devices” that check emissions of mercury, lead, arsenic and other metals for one year. Emissions tests in the last decade showed that the facility released higher levels of certain metals than expected.

In the most recent version of a Clean Air Act permit for the company, the EPA removed the multi-metals monitoring devices and instead requires the facility to install "activated carbon injections systems," devices thatwould reduce mercury emissions. However, the devices don’t monitor or reduce other kinds of metals. That concerns residents and environmental activists who say that addressing only one of the metals is not enough to protect public health.

The EPA gives an insufficient explanation for deciding not to monitor other metals, said Ken Miller, a scientist at the Washington University Environmental Law Clinic.

“People who live around these types of these facilities, whether it’s Veolia or any other hazardous waste incinerator, deserve to know that those facilities are not emitting any more of these things than the law and their permits require,” Miller said.

Credit Mapbox, OpenStreetMap Veolia Environmental Services' incinerator is located in the Metro East, where air quality has long been a concern.

Agency officials thought that Veolia’s proposal to install activated carbon injections systems would better protect the environment, EPA environmental engineer David Ogulei said.

“We believe by installing the control devices, we would achieve permanent reduction of emissions,” Ogulei said.

The agency noted that the decision to require multi-metals monitoring rested heavily on a performance test in 2008 that showed high levels of lead emissions from one unit. As the EPA noted in the most recent permit, Veolia retested the unit twice since 2008 and found that emissions were “far below the relevant standards.” Agency officials also expect emissions to decrease, based on their analysis of the waste going into the facility, said Ogulei.

However, the Jan. 2017 draft noted that the multi-metals monitoring was necessary to help the incinerator comply with the Clean Air Act.

“It makes me scratch my head a bit,” Miller said. “I don’t understand how if more stringent standards were not enough by themselves to ensure compliance at that time, how less stringent testing procedures now are good enough by themselves to ensure compliance.”

Credit Eli Chen | St. Louis Public Radio Doug Harris, general manager of the Veolia facility in Sauget, speaks at an EPA-hosted public meeting about the draft air quality permit.

Veolia opposes the installation of the multi-metal monitoring devices, mostly on the grounds that the technology is still developing.

“It is used on no hazardous waste incinerators in the entire world,” said Doug Harris, general manager of Veolia’s Sauget incinerator. “And the reason for that is it doesn’t work.”

According to the EPA’s responses to Veolia last year, multi-metals monitoring devices have been installed at multiple incinerators in the United States, though none of them are commercial facilities. They’re also used at many power plants, Miller said.

The EPA is taking public comments on the permit until Nov. 5.

This story has been updated to reflect the new deadline for public comments.

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