More than 450 natural gas compressor stations and processing plants have been built in Pennsylvania since 2008, when Marcellus Shale gas development kicked into another, higher gear.
Collectively, the rapidly multiplying facilities emit tens of thousands of tons of pollutants a year. And the growing emissions load may eventually lead to poorer air quality, according to environmental organizations.
Despite that emissions load, none of those Marcellus gas facilities are grouped together for permitting purposes by the state and labeled a "major source" of pollution -- a Clean Air Act designation that could require more extensive, and expensive, emission controls.
"There are a lot of shale gas sources right now with emissions just below the 100-ton-per-year 'major source' threshold," said James Duffy, an attorney with the Clean Air Council. "They're treated as minor sources. But put together, they are major sources and the people living next to them are receiving major doses of pollution. They should demand a remedy. And that would be emissions reductions befitting a major source."
However remedies are hard to come by, in part because of how Pennsylvania Department of Environmental Protection regulators apply emissions aggregation rules.
Two years ago, the Clean Air Council appealed a state decision to grant individual permits to a Marcellus Shale gas production facility and 10 gas compressor stations linked to it by pipelines, all in Washington County. Collectively those 11 facilities, all owned by MarkWest Liberty Midstream LLC, can emit more than 900 tons of nitrogen oxides a year -- or more than three times the amount emitted by U.S. Steel's Edgar Thomson steel mill in Braddock, which is designated a major source.
Together those MarkWest facilities also can emit more than 200 tons per year of carbon monoxide and 180 tons per year of volatile organic compounds -- pollutant emission totals well above the "major source" limit.
But the CAC in September agreed to settle its state Environmental Hearing Board appeal because MarkWest completed a new pipeline in July to another processing facility in Majorsville, W.Va., just across the Pennsylvania state line.
Because of the new pipeline -- which links to the 10 compressor stations plus five more also built by MarkWest -- Mr. Duffy said the CAC could no longer meet the adjacency part of the aggregation test.
That three-part test requires that facilities be commonly owned, that they share the same industrial designation and that they be "adjacent." The state's focus for the adjacency part of the test is on geographical closeness, while the U.S. Environmental Protection Agency, according to its long-standing practice, considers whether facilities are "fully interdependent."
Lawrence Demase, an attorney representing MarkWest in the appeal, said the case is the latest of four hearing board appeals settled recently and turned on whether functional interdependency should be part of the aggregation test.
"The problem with aggregation tests in the oil and gas industry is that the linkages are constantly changing as more wells and compressors are added in developing oil and gas plays," Mr. Demase said. "The new facilities produce a state of flux in terms of functional interdependence, so making that argument is hard."
The council agreed to settle its appeal in exchange for little more than a DEP promise to make more transparent and informed permitting decisions about aggregation. That speaks to the unsettled condition of state and federal regulations that are supposed to protect air quality.
Kevin Hawkins, MarkWest manager of investor relations, said that the appeal advanced arguments that are "contrary to the commonwealth's regulations and guidance, misapplied long-established EPA rules, and were inconsistent with a recent federal appeals court case dealing with the very same issues." His statement reflects the gas industry's position on aggregation.
However, the 6th U.S. Circuit Court of Appeals case from Michigan that Mr. Hawkins referred to is controlling only in that section of the country and contains some questionable legal reasoning, said Joe Osborne, an attorney for the Pittsburgh-based environmental organization, Group Against Smog and Pollution.
And the EPA still considers interdependency when determining adjacency.
In Pennsylvania, the DEP adopted an aggregation policy in December 2010, during the Rendell administration, that focused on interdependency when considering shale gas facilities' emissions. But by October 2011 the Corbett administration had put in place a new policy that de-emphasized dependency in favor of geographic proximity.
"Aggregation rules provide a great deal of discretion to permitting authorities," said Joseph Minott, executive director of the CAC. "And states are not taking aggregation seriously," he said. "It's something that the EPA should be looking at."
And it is, though it's taken a while.
The EPA was critical of the Corbett administration's new aggregation rules when they were adopted two years ago. Roy Seneca, an EPA spokesman, said this month the agency is still reviewing Pennsylvania's compliance with the Clean Air Act as part of a potential enforcement action.
Diana Esher, EPA Air Protection Division director for the Mid-Atlantic Region, said the EPA continues to look into the aggregation issue, as well as permitting, compliance and enforcement of natural gas development.
"EPA is familiar with the MarkWest facilities in Houston, Washington County, and Majorsville, W.Va. EPA representatives have been at both of these facilities," Ms. Esher said. "We are in communication with the Pennsylvania DEP and the West Virginia DEP about those operations and their compliance with state and federal environmental requirements. We cannot comment on the compliance status of the facilities at this time."
The Pennsylvania DEP, which issued the "general permits" to the MarkWest processing plant and each of the compressor stations in the case settled by the CAC, said in a written response to questions that its decisions on aggregation of shale gas facilities follow applicable federal and state laws and regulations.
"These determinations are made in the commonwealth on a fact-specific and case-by-case basis, applying the common-sense notion of [a] plant," said a statement issued by Lisa Kasianowitz, a DEP spokeswoman. "The department believes that the single source determinations are protective of public health and welfare and allow for the development of the natural gas industry in a safe and effective manner."
In response to questions, Ms. Kasianowitz said in an email that the DEP has done aggregation analysis on many shale gas facilities, but so far no bundling of facilities has been categorized as a major source. She said the department issued two aggregation rulings for facilities in the northwestern part of the state. Neither of those cases resulted in a major source determination, and the gas companies are appealing both.
Mr. Osborne said the state has aggregated few facilities and designated none of those a major source. "The reason," he said, "is the DEP's policies are not as rigorous as they ought to be or as federal policy."
Emissions declining overall
The impact of all those emissions from growing numbers of Marcellus Shale gas compressor stations and processing facilities is masked by a steep decline in nitrogen oxide emissions from other point sources like steel mills, factories and power plants that have either closed or switched fuel from coal to natural gas, Mr. Osborne said.
"We're not getting the improvements we should expect to see in our air quality because oil and gas emissions are hiding that progress," he said.
According to the DEP, point source emissions of nitrogen oxides declined from 235,485 tons in 2008 to 192,275 tons in 2011. The emissions from shale gas facilities accounted for 16,542 tons of that 2011 total, or 8.6 percent. During that same four-year period, the number of shale gas compressor stations in the state increased from 42 to 347, a jump of 305 facilities.
Since 2011, 157 additional Marcellus Shale gas compressor stations and processing plants have been built in Pennsylvania, each with the potential to add tons of nitrogen oxides to the air. If each of those compressor stations emitted 95 tons of nitrogen oxides a year, like eight of the 10 MarkWest compressors in Washington County that were the focus of the CAC appeal, they'd add almost 15,000 tons of nitrogen oxides annually, boosting the still-growing gas industry's share of NOx emissions.
Seventy-one of those compressor stations and processing plants are in Greene and Washington counties, south and upwind from Allegheny County.
George Jugovic, president and CEO of Citizens for Pennsylvania's Future, a statewide environmental organization, and a former regional director for the DEP during the Rendell administration, said the right question to ask is not what is aggregation but rather whether the existing state rule protects air quality.
"Aggregation is a legal issue that's really beside the point. What's important for a non-attainment area is how the air can be cleaned up as quickly as possible," said Mr. Jugovic.
"If we start backsliding on air quality because of all these new compressor stations and all the ones that are still to be built, that won't be good. Someone needs to be monitoring these sites and the state monitoring system is not set up to do that, especially in rural areas."
The shale gas industry discounts those concerns. Patrick Creighton, a spokesman for the Marcellus Shale Coalition, an industry lobbying organization, said the percentage share of the state's total NOx emissions, including mobile sources, is much less than even the 8 percent the DEP calculated from point sources.
And Kathryn Klaber, the coalition's CEO, issued a statement emphasizing the positive impacts of shale gas development on the state's air quality and supporting the state's aggregation policy.
"As we have observed over time and through DEP analyses, natural gas development presents only minor sources of emissions," she said. "Expanded natural gas production and use has been, and continues to be, a powerful market-based catalyst for improving our region's air quality and is also a driving force behind the historic reduction in emissions nationally, according to federal EPA and EIA [U.S. Energy Information Administration] data."
The DEP has not found unhealthy air pollution levels during three short-term monitoring studies conducted near Marcellus Shale gas operations at various locations in the state in recent years. But GASP criticized those studies as limited in scope and improperly designed, and for failure to consider long-term exposure risks and cumulative health impacts from airborne particle levels and ground-level ozone formation.
According to the EPA, even short-term exposure to nitrogen oxides can impair respiratory health, causing throat and lung inflammation and exacerbating asthma. It can also lead to higher concentrations of airborne particulate matter.
Results of a one-year study started in July 2012 to measure air impacts from shale gas operations in Washington County are due soon, and could, according to the DEP's website, help assess the cumulative impacts of emissions from shale gas processing and transmission.
But early signs that emissions from Marcellus Shale operations are already degrading regional air quality may be showing up at the Allegheny County Health Department's air quality monitor in South Fayette, said Jim Thompson, the county's air quality program director.
The monitor, on the southwestern edge of the county, is near the myriad shale gas facilities in Washington County, according to Mr. Thompson, and its measurements of ground-level ozone, formed from NOx emissions and a component of unhealthy smog, have been creeping up. "It's downwind from the MarkWest facilities in Houston. We can't say yet, for sure, if it's a significant trend, but it's something we have our eye on," Mr. Thompson said.
The Houston processing plant emits pollutants from several gas heaters, seven 30,000-gallon gas storage tanks, a truck-loading operation and several refining facilities. It operates under "general permits" issued by DEP, including those issued two years ago that were the object of the Clean Air Council appeal.
"Compressor station emissions are already tightly regulated, so aggregation would have minimal effect on reducing them," Mr. Thompson said. "But they would have to get NOx off-sets and do modeling of how their emissions would affect air quality because they're in a non-attainment area for ozone and NOx. That could change things."
Don Hopey: email@example.com or 412-263-1983. First Published October 6, 2013 4:00 AM