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Tackling Risks of Thermal Systems in Maine

July 29, 2008 - Hundreds of geothermal systems are believed scattered across Maine, heating and cooling homes, businesses and public buildings via wells that plunge more than 300 feet below ground.

Only six of the alternative energy systems are registered with the Maine Department of Environmental Protection as required under federal and state law, according to state officials.

Now the state is trying to assess the risk posed by so many systems and impose some oversight without discouraging investment in the technology at a time when soaring heating oil costs are prompting more people to look for new ways to heat homes, schools and commercial buildings.

No one knows for sure how many geothermal systems are in Maine, although state officials estimate roughly 500 exist. But an untold number of them have failed, causing or risking groundwater and well contamination ranging from motor oil and refrigeration chemicals to saltwater and arsenic, the officials said.

And still, the state has no laws or regulations that require geothermal systems to be licensed or reviewed before they are installed, or to be monitored once they are. The state gets involved only when systems involve water discharge, and that's what the state environmental agency focuses on.

Engineers and others who know these systems say the lack of oversight is a disaster waiting to happen. Forty-three percent of Maine's 1.3 million residents rely on private wells for domestic water, and 20 percent of water supplied to public systems comes from groundwater sources, according to the U.S. Geological Survey.

As fuel prices rise and interest in alternative energy sources explodes, "We need to promote this technology. It just needs to be done right," said Erich Kluck, an environmental specialist who runs the state's Underground Injection Control Program. "If we don't have clean drinking water, the price of oil isn't going to matter."

Kluck is among 20 state environmental officials and others involved in geothermal technology and groundwater protection who met last week to start revamping the state's approach to geothermal systems. Participants included representatives of the seven-member Maine Well Drillers Commission, a governor-appointed panel that licenses well drillers and establishes performance standards.

Divided into two groups, the participants are expected to meet several times in the coming weeks and reconvene as a whole in September to share their findings, said Malcolm Burson, Maine DEP's associate policy director.

Geothermal systems take advantage of near-constant 50-degree temperatures 300 feet below the Earth's surface to heat or cool buildings. Water or antifreeze solution in underground pipes takes in or gives off heat that is concentrated and circulated by pumps. Depending on the design and technology used, some are closed-looped systems and some tap directly into groundwater.

Problems can arise when systems are too close together, which diminishes heating and cooling capacity; when pumps fail, which can leak oil, coolant or other chemicals into the ground; when groundwater has high levels of arsenic, radon or other naturally occurring chemicals; or when underground systems tap into seawater, contaminating nearby drinking wells.

Burson said the DEP wants to determine how existing state laws, agency regulations and well-drilling rules should be changed, what public education programs are needed and whether municipal ordinances may be necessary to institute local oversight.

"DEP would not become the regulator of geothermal systems," Burson said.

With such a short list of state-registered systems, Kluck said he's not sure where he'd start if DEP took charge of geothermal regulation.

The six registered operators include Bowdoin College in Brunswick, the York County Courthouse in Alfred, Westbrook Middle School and a private home in Raymond, Kluck said.

The list of unregistered geothermal systems is long and includes numerous public and well-known buildings, such as the Abromson Center at the University of Southern Maine and the U.S. Customs House in Portland, Gorham Middle School, Camden Hills Regional High School and the Colby College Alumni Center.

While well-drilling companies must register drinking-water wells with the Maine Geological Survey, current law requires property owners to register geothermal systems with DEP.

Kluck has been prodding owners of geothermal systems he knows about to register, and several are in the process of submitting forms, he said. Having a complete list would help identify potential areas of system failures and groundwater contamination.

Kluck said he knows of several systems that have failed, but only one that DEP was involved in cleaning up. Four years ago, a new owner of a private home in South Bristol removed a 20-year-old geothermal system that had leaked freon, a common refrigeration chemical, into the owner's well and a neighbor's well. The well is no longer considered contaminated, Burson said.

DEP is responding, in part, to growing concern among municipalities, especially along the coast, where more affluent homeowners can afford the $16,000 to $40,000 cost to install a geothermal system.

That's why the agency tapped Lissa Robinson, a civil engineer and hydrogeologist in Falmouth who consults for municipalities, to help review geothermal oversight in Maine.

"Towns are interested in balancing groundwater protection and human land use," Robinson said. "These towns are wondering what role they need to play in maintaining that balance when it comes to geothermal technology."

Douglas Martin, president of W.H. Demmons Inc., a Portland firm that has designed and installed about 25 geothermal systems since 1992, said he welcomes DEP's interest in improving oversight.

Some of the firm's early projects had problems, Martin said. "With every job, we've gotten better at what we're doing," he said.

Last year, Demmons installed two geothermal systems, including one at the York County Courthouse, that saved a combined 54,000 gallons in heating oil in a 12-month period. The courthouse system, in particular, saved York County taxpayers nearly $70,000 in fuel costs, according to county officials.

Martin said the state should require that plans for geothermal systems be reviewed by a registered engineer and a hydrogeologist, as his firm now does. He also has started registering geothermal systems designed and installed by his firm rather than waiting for property owners to do it.

Martin said geothermal technology is a viable way to reduce dependence on oil and other nonrenewable energy sources.

"But it also has the potential to do great damage to public water supplies," he said. "I have a vested interest in wanting to make sure people do this properly."

By KELLEY BOUCHARD, Staff Writer, Portland Press Herald, July 28, 2008


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