EGLE: Prince Drewry Park methane levels steady

By: Nick Mordowanec | C&G Newspapers | Published August 6, 2020

 Prince Drewry Park is said to have stabilized methane gas levels due to vents installed in 2019. The park is close to an elementary school and neighborhood.

Prince Drewry Park is said to have stabilized methane gas levels due to vents installed in 2019. The park is close to an elementary school and neighborhood.

Graphic by Jason Clancy


CLINTON TOWNSHIP — Methane gas levels seem to have stabilized at Clinton Township’s Prince Drewry Park, according to a representative from the Michigan Department of Environment, Great Lakes and Energy.

A public meeting was held last year to discuss the increased presence of methane at the park, and to ensure residents that their safety was the top priority.

A Clintondale Community Schools elementary school, Robbie Parker, is located adjacent to the property, to the east of it.

The park was originally a gravel pit that was later used as an unlicensed landfill. According to Clinton Township Public Services Director Mary Bednar, information is scarce regarding the extent and depth of the waste and its timeframe of operation.

She said it was previously used as a waste dump mostly for household trash. Clinton Township, along with five Grosse Pointe communities and the city of Harper Woods, utilized the site decades ago as part of the Grosse Pointe-Clinton Refuse Disposal Authority.

In December 2019, eight gas vents were installed to prevent the migration of methane. They are about 15 feet deep and 15 feet high in the air. EGLE noticed an increase in the odorless gas beforehand.

Bednar said wells were installed in the spring of 2019 to monitor methane levels, and currently, “the vents are in and working properly.” The risk with methane gas, she added, is that increased levels in tight spaces could actually cause explosions.

“(EGLE is) not seeing that gas is migrating,” Bednar said Aug. 3.

Residents in the vicinity were given gas detectors to put in their homes “in case there was an accumulation,” while a detector was also placed in a restroom at the park. Bednar said, “To date, I know of” zero detectors being triggered.

On July 27, during the Township Board of Trustees’ virtual meeting, EGLE senior geologist Greg Barrows — who works out of EGLE’s Southeast District Office, in Warren — discussed how EGLE has been investigating the Prince Drewry site for years.

He said that due to the ground beneath the park being sand and gravel, and surrounded by natural clay, gas is able to escape upward rather than move laterally into confined spaces.

“The main hazard being posed by the site, based on the geology, based on its proximity to homes, based on the cap, is the fire and explosive hazard posed by the methane gas itself, so we really wanted to make sure that was not a problem migrating away from the site,” Barrows told the board.

A recent site sampling showed no refuse and contaminants associated with the landfill, he added, with data showing steady levels of methane. He, too, stated that no alarms have been triggered.

As to whether the installed vents are working as expected, Barrows said, “That’s indeed what we see.”

He also touched on the landfill cap, or the ground covering the landfill, saying that EGLE probing revealed about 10 feet of thickness in the middle, which tapered to about 1 foot on the edges.

Anything compromising the cap, such as deep-rooted plants, should not be a concern.

Township Supervisor Bob Cannon praised EGLE’s diligence in the matter.

“I was very impressed with the attention that EGLE gave to this project so quickly,” Cannon said. “As soon as the methane levels began to rise, they were on the spot.”

Bednar said EGLE is likely to conduct weekly monitoring sessions of methane levels until the end of this year, at which point it may reevaluate the testing schedule.

Barrows could not be reached for further comment at press time.