Lancaster County's largest emitters of greenhouse gases include the county incinerator, two landfills, a natural gas pipeline compressor station and three industries.

But all those sources combined are dwarfed by the 9 million metric tons of carbon dioxide that PPL's coal-fired Brunner Island power plant released into the air just across the Susquehanna River during 2010.

The Brunner Island plant was among the top 100 emitters of greenhouse gases in the United States, according to a new survey by the U.S. Environmental Protection Agency.

For the first time, EPA has released to the public greenhouse gas emissions data reported directly from 6,700 facilities across the country. The database is at ghgdata.epa.gov.

The figures show the county's trash-to-energy incinerator in Conoy Township was the top emitter of local greenhouse gases, with 147,220 metric tons of carbon dioxide during 2010, as well as 2,765 tons of methane gas and 5,359 tons of nitrous oxide.

The main source of carbon dioxide at the incinerator is the burning of plastics thrown in the trash, said James Warner, chief executive officer of the Lancaster County Solid Waste Management Authority.

"The fact is, 40 percent of the garbage that is processed is fossil-fuel derived, and most of that is plastics," Warner said.

"It is what it is. Until technology is developed to lower carbon dioxide, or sequester it, you just have to go about your business and look for other ways to minimize it. And those are slim right now."

Lancaster County is fortunate to have a resource-recovery incinerator to dispose of most its waste rather than a landfill, he said, because decomposition of trash creates large amounts of methane gas, which is 21 times more potent as a greenhouse gas than carbon dioxide.

The authority currently captures much of the methane gas generated from decomposition of trash at the old Creswell Landfill and the current Frey Farm Landfill. The gas is piped to a PPL gas plant and converted to electricity.

But not all methane gas is captured, and the Frey Farm Landfill was listed as the fifth-largest source of greenhouse gases in the county because of escaping methane gas.

Another landfill, the Lanchester Landfill on the Lancaster-Chester county line, was number four among emitters, almost completely for methane gas.

Texas Eastern's pipeline and compressor station outside of Marietta was sixth on the list.

Three industries completed the list of major greenhouse gas emitters here.

The Alcoa Mill Products plant on Manheim Pike was second, Armstrong World Industries' ceiling plant at Marietta was third and the Kellogg cereal plant near Landisville was seventh.

Responding to the greenhouse gas totals for Brunner Island, PPL spokesman George Lewis said the ranking of the plant in the EPA's listing "reflects the plant's size and how reliably it operates. The plant generates about 10 billion kilowatt-hours of electricity a year, which is enough to supply about 1 million average homes. Currently, no technologies are available to capture or reduce carbon dioxide emissions from large fossil-fuel power plants like Brunner Island.

 "The Brunner Island plant is in compliance with existing regulations and meets the requirements of its air permits," Lewis said. "PPL is an environmentally responsible company and has invested more than $800 million at the Brunner Island plant over the last 5 years on scrubbers and other environmental upgrades to reduce emissions of sulfur dioxide, mercury, particulates (soot) and other air pollutants. We expect we will need to make additional investments at Brunner Island in the future to meet requirements of pending new EPA regulations.

 "PPL has made a commitment to the Brunner Island plant for the long term. It's an important resource for PPL and for the regional power grid because it generates so much electricity. It's also a major contributor to the local economy, providing about 300 full-time jobs."

EPA's survey of greenhouse gas emitters did not include sources from agriculture, forestry, transportation or smaller emitters.

Still, EPA says the survey accounts for about 80 percent of all greenhouse gases emitted in the United States.

EPA noted that greenhouse gas emissions themselves are not harmful to the public.

"Instead, greenhouse gases contribute to global warming, causing Earth's climate to change, which in turn endangers human health and welfare.

"For example, a warmer climate will increase the risk of heat-related illnesses and death, and will worsen conditions for air pollution."

The country's largest emitters of greenhouse gases were coal-fired power plants. Pennsylvania was second only to Texas as a source of gases from power plants.

That is no surprise, noted Jan Jarrett, president of PennFuture, a statewide environmental group. But the greenhouse gas survey, she said, "gives us a picture of how big of a contributor that we are. Pennsylvania contributes 1 percent of the entire globe for carbon dioxide."

The survey, she suggested, should challenge Pennsylvanians to move away from coal-fired generation and increase the amount of power they get from such renewable sources as wind and solar, as well as increase conservation of energy.

She applauded the Pennsylvania Legislature for Act 129 in 2008 that required utilities to cut demand for electricity. Utilities offering financial incentives to residential customers to conserve electricity and rebates to commercial users have helped the state make "great strides," she said.

At the same time, Pennsylvania has many old, small and inefficient coal plants that should be retired, she said.

Last year, Exelon closed two old coal-fired plants along the Schuylkill and Delaware rivers. And several weeks ago, Sunbury Generation LP announced its intentions to convert its Sunbury plant along the Susquehanna to burn natural gas instead of coal.

acrable@lnpnews.com