Webinar slated for Feb. 21HARRISBURG, Pa., Feb. 12, 2013 /PRNewswire-USNewswire/ -- The Department of Environmental Protection announced today it has released emissions data for the unconventional drilling industry and will discuss the results in an upcoming web-based presentation on Thursday, Feb. 21, at 2 p.m. The data represents 2011 emissions from natural gas production and processing facilities, such as wells and compressor stations. "The data show that emissions from drilling represent a small fraction of air pollution in the state, which has gone down considerably since shale gas development began in earnest several years ago," DEP Secretary Mike Krancer said. "Natural gas is a domestic, abundant, clean-burning fuel source, and we have the regulations in place to assure that air emissions during drilling and transmission do not compromise the environmental benefit of natural gas as a fuel for electricity and transportation." For the inventory, 57 operators of unconventional wells and 40 mid-stream operators of 150 compressor stations reported data. Compressor stations help move natural gas from well sites to larger pipelines. Since 2008, air emissions across the state are declining. While unconventional gas production and processing emitted 16,542 tons of nitrogen oxides in 2011, emissions of the same pollutant have fallen 43,000 tons per year. "It is worth noting that annual sulfur dioxide emissions are down more than half a million tons per year from where they were in 2008," Krancer said. "This is a direct result of air quality regulations and the increased use of natural gas in the power generation sector." Emissions of fine particulate matter and volatile organic compounds are also down, both within the power generation sector and across the state. DEP must submit a comprehensive air emissions inventory to the U.S. Environmental Protection Agency every three years. The inventory includes emissions data from sources such as refineries, manufacturing plants, power plants, dry cleaners and cars, trucks and other vehicles. DEP collects emissions inventory data from the point sources annually, and Act 13 of 2012 requires the owners or operators of the unconventional natural gas sources to submit an annual emissions inventory to DEP by March 1 of each year. DEP recently announced, for the next inventory submission due March 1, 2013, that conventional oil and gas compressor stations must report emissions data for 2012. In 2010, DEP conducted short-term air quality monitoring studies in the southwest, northeast and north-central regions of the state. The studies did not identify concentrations of any compound that would likely trigger air-related health issues associated with Marcellus Shale drilling activity, nor did DEP detect concentrations above federal ambient air quality standards for carbon monoxide, nitrogen dioxide, sulfur dioxide and ozone at any of the sampling sites. DEP is in the midst of a year-long air monitoring study in Washington County in the southwest region of the state to determine potential air quality impacts associated with the processing and transmission of unconventional natural gas. The data from the study will allow DEP to assess any potential long-term impact of emissions from unconventional natural gas operations to nearby communities. DEP also recently announced significantly lower allowable emissions for compressor stations permitted under a general permit, called GP-5. The agency is accepting comments on a proposed revised permit exemption for well heads and associated equipment that specifies emissions control criteria that must be met to qualify for the exemption.