An 884-page investigative report confirms that dangerous levels of cyanide are present in groundwater near – but not yet in -- both West Grand Traverse Bay and the Boardman River on the west side of downtown Traverse City.
The report, authored by environmental consultant AKT Peerless, was ordered by the Grand Traverse Brownfield Redevelopment Authority (BRA).
The centerpiece of the investigation and subsequent report is a map that details where -- and at what levels -- cyanide is present at the intersection of Hall Street and West Grandview Parkway near the Candle Factory and the Hotel Indigo now under construction.
The map shows an underground plume of “available” cyanide in the groundwater spanning an approximate city block-sized area that crosses West Grandview Parkway and into the groundwater underneath the beach. The groundwater does not come in contact with surface water of the Bay.
The highest concentration of cyanide was found in groundwater under the new Hotel Indigo at Garland and Hall Streets. “Available” cyanide is of most concern to environmentalists, BRA officials and the Michigan Department of Environmental Quality (DEQ) because it is the measurement the DEQ uses to determine if there is a risk to direct contact with water, animals, or humans.
The findings are based on thirteen groundwater samples, twelve soil samples, and eight samples of West Grand Traverse Bay surface water, all taken by AKT Peerless in late June.
A second map shows “total” cyanide present in a much larger area -- including into groundwater under the Bay itself -- though AKT Peerless officials stress that “total” cyanide includes many forms of cyanide that very stable and essentially harmless to humans.
“I want to make sure people understand,” AKT Peerless Senior Geologist Doug Kilmer tells The Ticker, “that levels of cyanide where the DEQ would deem them unhealthy is one hundred times or more higher than what we’re seeing near the Bay. This is a problem obviously, but not a crisis.”
Both Kilmer and Jean Derenzy of the BRA spoke to The Ticker at length about the report, highlighting several points, including:
Though the highest concentration of cyanide was found to be the Hotel Indigo property, that site is not the source of the problem. The source is very likely across Hall Street behind the Candle Factory, where a coal gas gasification facility operated from 1901 until 1945 and later a food cannery. Both industrial uses are known to have generated or utilized forms of cyanide.
Groundwater naturally flows from the affected area south toward the river and north toward the Bay, but the process is very, very slow. “It obviously takes years,” says Kilmer. The gas plant started more than 100 years ago and stopped in 1945, and it’s taken this long to move this distance.”
This report is a “snapshot in time,” according to Kilmer, noting that, just weeks after the samples were taken in the area, Hotel Indigo began its required “dewatering” process of pumping millions of gallons of water out of the ground for pre-treatment before sending it into the public water treatment system. “The dewatering is now pulling a lot of groundwater toward that [Indigo] site, and that would influence these maps,” he says. “So over time this plume that you’re seeing on the map will ebb and flow and change shape and could be in a different location.” He adds that further testing should be done again once Indigo’s dewatering ends later this year.
What’s next? Remediation of the site, which AKT Peerless says could take several forms, ranging from changing the cyanide’s chemistry and stabilizing it, removing it, or building barriers to stop it from flowing toward the bay.
Derenzy says the BRA will likely engage AKT Peerless again to now determine the “most effective method for remediation.”
Construction of Hotel Indigo will continue as planned (hotel developers are following agreed-to remediation and construction methods for their property, and Kilmer says any eventual contamination on or near the site would not impaired by the construction of a hotel).
Derenzy prepared for the worst months ago when she and the Brownfield Authority applied to the State Land Bank Authority for $600,000 to help implement some or all of the recommended remediation in the area, though she now admits “there will be a gap between the original request and what will ultimately be needed” to cleanup the entire affected area.
That portion of Traverse City is likely to see more redvelopment in the coming years, which Derenzy says led her to “be proactive, find out what the problem is, where it is, and address it once and get it done,” instead of “a piecemeal approach by going through this with each and every future project.”
The report will be presented to the Brownfield Redevelopment Authority during a special meeting Wednesday morning.