Tuesday afternoon's meeting of the Elk County Solid Waste Authority was held at the Veolia ES Greentree Landfill in Fox Township. Prior to the meeting, authority members toured the site by bus and received an update about what has been taking place.
The landfill, which was established in 1987 and changed hands several times before coming under its current management, encompasses about 3,000 acres, with between 400 and 500 acres currently active under the facility's permit boundary.
Veolia Special Waste Coordinator Anthony LaBenne said the landfill can accommodate about 6,000 tons of waste per day and is currently averaging between 3,300 and 4,000 tons daily. At a scale house, every load coming in is weighed and scanned for radiation. Weight, contents and where it is to go in the landfill are recorded. The waste is then taken to a cell, an area in the ground that has been prepared to accept the waste. At the working phase of the landfill, all of the trash goes to an active cell, where it is dumped, compacted and later covered with soil at the end of the day; the process is repeated anew daily. Additional wells for the collection of methane gas have recently been added to help control odor.
Responding to a query about where most of the landfill contents are coming from, LaBenne said approximately 60 percent has been coming from out-of-state over the years, but has been reduced due to Marcellus Shale activity. The facility has been receiving drill cuttings, or materials removed from a borehole in the process of drilling wells.
"Now with all the drill cuttings coming in, it's probably about 40 percent out-of-state," he said.
LaBenne also pointed out a large tract of grass-covered hills and explained that it contains cells that are full.
"Everything that's green has already been capped," he said. "Nothing more goes into it."
He said Veolia maintains ongoing safety procedures, including monitoring water in active areas to determine if there are any harmful levels of chemicals which could signify leakage from one of the cells.
"All water from the landfill that comes into the plant is called leachate. It's chemically and biologically treated," LaBenne said.
He explained that active landfill cells are layered with a variety of barriers, including plastic liners, clay and gravel, to prevent leachate from seeping or contaminating water sources. If the monitoring indicates seepage, employees at the landfill can pinpoint the cell and prevent further leakage.
LaBenne said any tires that go into landfills have to be chipped and shredded because if left whole, they "float" to the top of the cell, even though the cells contain solid material. Veolia has been approved by DEP to use tire shred as drainage material around pipes on the property.
LaBenne said waste coming in as liquids may not be put directly into a landfill, so any liquid is first placed into a special area with other materials, including fly ash and lime, until it becomes solid and can be moved to a cell. Although it has a permit to do so, the landfill does not accept medical waste from hospitals per its agreement with its host municipality, Fox Township.
"We get municipal waste from hospitals, but we don't get any biohazard, red bag, autoclave, things like that. We don't get any of that," LaBenne said.
He said Greentree is one of the largest landfill converters of methane gas to energy in the country. The methane gas released from waste at the landfill is captured through a network of pipes and travels to a gas treatment plant on the property.
"All the landfill gas that's produced by the landfill comes to this building," LaBenne said. "It goes through a series of filters and processes that take the gas and clean it. They remove all of the impurities from it."
The process produces almost 100-percent pure methane gas, which is then piped several miles to National Fuel's pipeline.
"We pipe it nine miles to the top of Boone Mountain to the compressor station. At that point, it hooks into National Fuel's pipeline. Then it just gets mixed in as a green energy source," LaBenne said.
According to Greentree's website, about two billion cubic feet of the purified gas flows to the pipeline each year.