State Representative Lon Burnam, Dem. Fort Worth, asked nine questions of the Texas Commission on Environmental Quality concerning its investigations of emissions of methane and volatile organic compounds from oil and gas operations in the Barnett Shale area and in Texas in general. Recent air quality tests by private companies for local towns in the Fort Worth area have created a stir and caused some to call for increased monitoring and additional testing of emissions from oil and gas operations. Rep. Burnam has also called for the City of Fort Worth to place a moratorium on issuing permits for drilling until additional testing has been done. A group of concerned citizens has formed the North Central Texas Communities Alliance, to press for a moratorium in the DFW area until environnmental and other concerns are addressed.
The TCEQ’s response to Rep. Burnam’s questions provides some interesting data.
The TCEQ has used infrared imaging cameras (IR cameras) to identify sources of emissions of methane and volatile organic compounds (VOC’s) from industry sites in Texas. The IR cameras do not measure the quantity of the emissions, but identify potential problem sites. TCEQ issues permits allowing emissions of regulated contaminants, including methane and VOC’s, and part of its job is to assure that industrial sites have proper permits and that their emissions comply with those permits. The TCEQ says, that, since 2005, it has conducted IR camera surveys of more than 1,000 sites at oil and natural gas sources in 58 Texas counties, mostly around individual tanks or tank batteries and compressor stations.
A survey of the Gulf Coast and North/Central Texas areas in 2007 using IR cameras showed 64 sites in the Gulf Coast area and 93 sites in the North/Central area with visible emissions. The agency selected 10 sites in the North/Central area and 10 sites in the Gulf Coast area to investigate further. Nine companies own or operate the 20 sites. TCEQ asked the site operators to conduct tests of its emissions. Six sites did not submit data. Data from 14 sites showed emissions in excess of permitted limits. The TCEQ estimated that the 20 sites emitted 2,297 tons of VOC’s in 2005. After TCEQ worked with the operators to reduce their emissions, the TCEQ estimated that VOC emissions from those sites in 2007 was reduced to 90 tons. TCEQ said that most reductions in emissions were achieved by decreased production.
As a result of the 2005 IR camera survey, the TCEQ developed a project to test emissions from storage tanks used in the upstream oil and gas industry. Based on this project, the TCEQ increased its estimate of emissions from storage tanks in Texas by a factor of 3 to 11, a total increase in estimated annual emissions of 620,000 tons. TCEQ estimates that 2008 emissions of VOCs from upstream storaget tanks in Texas were 1,128,766 tons, equivalent to 8,639,647 barrels of oil.
The “best available technology” for reducing emissions from storage tanks is a vapor recovery unit. Such a unit captures the VOCs that evaporate in tanks and allows them to be sold as part of the production stream. Rep. Burnam asked TCEQ how long it would take a producer to recover the cost of installing a vapor recovery unit for a typical well in Texas. TCEQ referred Burnam to a study conducted by the EPA showing that the cost of a vapor recovery unit could typically be recovered between 3 and 19 months, depending on the price of natural gas. “The Environmental Technology Verification Program at EPA evaluated the Eductor Vapor Recovery Unit (EVRU) from COMM Engineering. The $108,000 EVRU recovered 175 Mscf/day. Assuming a prices value of $5.46 per Mscf, the total value of recovered gas was estimated at $650,000 per year for an approximate two month payback.” The EPA has developed a tool to estimate costs and assumptions and calculate a payback for installation of vapor recovery systems, available online.
TCEQ’s complete answers to Rep. Burnam’s questions are available here.
In response to air quality tests conducted for the town of Dish, near Fort Worth, the Texas Pipeline Association, and industry group, began working with TCEQ to investigate emissions of VOCs from industry facilities around Dish. Dish’s air quality tests have stirred up significant controversy.
VOCs are greenhouse gases. With expected increases in regulation of greenhouse gases and increased drilling activities in urban areas, particularly those like the DFW area which are “non-attainment” areas for air quality, it can be expected that the petroleum industry will face increasing pressure to use best available technologies, including vapor recovery systems, to reduce emissions of VOCs from petroleum storage tanks.