Emissions from compressors, venting of gas and dust are all air quality issues being dealt with by coalbed natural gas producers. Regulations exist to safeguard the air.
Coalbed natural gas wells produce at relatively low pressure and require the assistance of compression to reach pipeline pressures. Companies have undertaken great efforts to ensure that air emissions are kept to a minimum. The engines driving the compressors are burning coalbed natural gas, which at 95% pure natural gas, is clean by nature. To further reduce emissions, engines combine the latest technology to meet or exceed state and federal regulations for best available control technology (BACT). These technologies include lean burning engines, computer-assisted air/fuel ratio controllers and exhaust catalyst. Computer simulations are performed to ensure that ambient air quality standards are met before an air permit is issued. These models account for the manufacturer’s emission data and how an engine is situated on a location, as well as the area’s meteorological data and cumulative effects of nearby installations. No sites are permitted if air quality standards are not met. Regular testing is required after installation to ensure facilities meet or exceed standards.
There have been concerns about the venting of coalbed natural gas as part of proving reserves. Both the Wyoming Oil and Gas Commission and the Montana Board of Oil and Gas Conservation have established rules related to venting of gas. These rules limit venting both in time and volume. Rules of the Commission and Board of Conservation can be accessed either by calling their offices or by visiting their websites. There is no flaring of gas associated with the development of coalbed natural gas.
Other concerns have been raised about dust. During the production phase, equipment is moved onto the site. Unlike traditional oil and gas operations, coalbed gas wells take a few days to drill and traffic in and out of the drilling site is limited to that timeframe. Ongoing monitoring of the wells and equipment is expedited by bringing individual wells together to a pod metering building. As many as ten or twelve wells can all be checked at one site, reducing traffic ten or twelve fold. In some cases, electronic flow measurement equipment has been installed which further reduces the need to visit individual sites. Operators utilize existing roads to the greatest extent possible, including two-track roads. Minimal road building is done in association with coalbed natural gas development.