The quarry landfill in Rockland. Credit: Stephen Betts / BDN

After floating closure plans for the last decade, Rockland may finally be moving closer to closing its landfill for good.

Rockland is home to one of the last remaining quarry landfills in the state. The city-owned dump is located on Limerock Street and has been used only for the disposal of construction and demolition debris in recent years. That’s in part because the larger-scale debris fills the space more rapidly than general trash does — something that needed to happen in order for the landfill to reach capacity.

Once it’s at capacity, it can finally be transitioned to closure.

“We are anxious to close it and put it back into a true transfer station and be done with it,” Rockland City Manager Tom Luttrell said. “But the monitoring will be ongoing forever.”

The only other operating quarry landfill in the state is located in nearby Rockport. Since quarries are filled with groundwater, the practice of disposing of waste into them has been prohibited since the 1970s. Both the Rockland and Rockport landfills are allowed to continue to operate because they were in operation prior to the prohibition.

The Rockland dump — a former limestone quarry — has been in use since the 1930s and has been used for many trash disposal purposes during its lifespan.

Around 2008, the city started accepting large hauls of debris from contractors across the state inorder to rapidly fill the quarry and expedite its closure, as well as to bring in additional revenue for the city.

In 2018 the city temporarily stopped accepting these types of larger loads of debris, thinking that the landfill was nearly at capacity. However, it reopened about a year later after city officials realized there had been a capacity calculation error.

With the landfill now reaching its true capacity, the city will once again stop accepting the large loads of construction debris from contractors. The anticipated end date for this type of disposal is Dec. 31, according to Luttrell. City residents will still be able to dispose of smaller amounts of debris over the next six months, Luttrell said.

The city is currently working with the Maine Department of Environmental Protection to receive a permit to begin the multi-year process of closing and capping the landfill, after it closes at the end of the year.  Capping a landfill entails placing a cover over its contents to stop the spread of contamination, according to the U.S. Environmental Protection Agency.

This would be the second — and final — quarry-based landfill that the city has closed, with an older quarry landfill being capped sometime before the 2000s, Luttrell said.

Closing the landfill is estimated to cost about $3 million, according to Luttrell. With about $1.5 million in a reserve account, the city plans to ask voters in November 2022 to approve a bond of about $1.5 million or $2 million to fund the rest of the closure project.

If the bond is approved, the city is hoping to finalize the closure by the end of 2024, Luttrell said.

In the last decade, the city  installed a gas collection system within the landfill, to collect and burn off methane gas produced below the surface in an aim to reduce the odors the gas creates.

But even when the landfill is capped, the city will still need to pump the groundwater that collects deeps below the surface down to a certain level, as well as monitor the surface to make sure the landfill isn’t settling. Luttrell said these issues are more prevalent with a quarry landfill than a traditional landfill.

“It’s going to be a lifetime of monitoring of the quarry,” Luttrell said.