Update: Threat eased after equipment shutdown

HOWELL, MI — Health officials say a cancer-causing chemical in the air near a Livingston County manufacturing facility poses an “imminent and substantial” danger to the public after industrial emissions testing found high levels leaking from rooftop vents.

The U.S. Environmental Protection Agency and Michigan Department of Environment, Great Lakes and Energy (EGLE) are testing air inside homes around Diamond Chrome Plating in Howell after the state health department began sounding the alarm about test results that show high levels of trichlorethylene (TCE) escaping the factory.

TCE is an industrial solvent used as a vapor degreaser at Diamond Chrome, located at 604 S. Michigan Avenue about a quarter mile south of downtown Howell in a largely residential area.

Exposure to TCE is linked to birth defects and immune system issues, as well as an increased risk of kidney and liver cancers and non-Hodgkin’s lymphoma. The EPA has classified TCE as a known carcinogen.

A public meeting is scheduled Thursday night, Nov. 21, from 7 to 9 p.m. at the Parker Middle School at 400 Wright Road in Howell.

According to state documents, TCE was measured on Aug. 8 at nearly 14 times the state’s residential health screening level of 2 micrograms per cubic meter (ug/m3) near 220 S. Michigan Avenue, about four blocks north of the Diamond Chrome plant.

On Nov. 4, TCE was measured at 11 times the screening level at 110 Brooks Street, which is about 400 feet north of the plant.

Both tests were taken downwind of Diamond Chrome. The August samples correspond with rooftop vent testing showing TCE at concentrations of 1,268 and 1,103 ug/m3 escaping as “fugitive” emissions while the degreaser was operating.

Data from @MichiganHHS shows TCE levels coming from Diamond Chrome Plating rooftop vents and in the ambient air around Howell residential blocks. pic.twitter.com/N7vGNCl8sC — Garret M. Ellison (@garretellison) November 21, 2019

The Michigan Department of Health and Human Services (DHHS) received the Nov. 4 ambient air test results last week. On Monday, Nov. 18, DHHS toxicologist Deb MacKenzie-Taylor sent a letter to the Livingston County Health Department declaring the emissions an “imminent and substantial endangerment to public health.”

Because TCE vapors are denser than air, they sink to the ground when released by ventilation, according to MacKenzie-Taylor’s letter.

“Trichloroethylene emissions from DCP must be halted immediately to protect the public from the potential acute health effects of trichloroethylene, including but not limited to fetal cardiac malformations,” MacKenzie-Taylor wrote.

The county health department ordered Diamond Chrome to stop emitting TCE and began knocking on doors in Howell this week.

Messages left with Diamond Chrome Plating’s owner Jerry Chinn and two company environmental managers on Wednesday were not returned.

Regulators say the company has stopped using the TCE degreaser. “They’ve been cooperative, at least with me,” said Livingston County environmental health director Matt Bolang.

Interim Howell City Manager Ervin Suida said the area around Diamond Chrome’s factory is a mix of residential homes and businesses. So far, he said the public hasn’t reacted strongly.

“We haven’t received any phone calls as of today,” said Suida.

Escalating scrutiny on Diamond Chrome emissions began to develop this year after EGLE (formerly the DEQ) began noticing TCE in routine air samples associated with an old dry cleaner that didn’t use the chemical, said Mary Ann Dolehanty, EGLE air quality division director.

Diamond Chrome has a history of air and water pollution permit violations and EGLE began looking at the company as a possible source.

Diamond Chrome uses chromium, cadmium and nickel to plate aircraft landing gear, commercial hydraulics, industrial dies and other miscellaneous parts. The company began operating in Howell in 1953 and its various pollution issues include releases of hexavalent chromium, cadmium, cyanide, lead, chlorinated volatile organic compounds, per- and polyfluoroalkyl substances (PFAS), and other compounds into the Howell storm and sanitary sewer systems, soil and groundwater.

Diamond Chrome signed negotiated court orders with the state in 2006 and 2015 to address air and water pollution issues. In 2018, the company was found to be sending high PFAS levels to the Howell wastewater plant, which discharges to the Shiawassee River.

“This is a situation where we have a long-standing non-compliance issue,” said Dolehanty. “Even after the (2006) consent decree, we have issued violation notices.”

This year, EGLE has sent Diamond Chrome three air pollution permit violation notices since June; the most recent on October 30 for failure to contain TCE emissions. “It has been sort of a struggle with that company to get them into compliance,” she said.

An added wrinkle to the TCE emissions is the fact that EGLE’s air quality division doesn’t have typical regulatory authority over the degreaser inside the facility because it’s not supposed to emit gasses outside of the factory walls, Dolehanty said.

“In that context, to have an exempt piece of equipment like that with these levels of emissions is a bit unusual,” she said.