Document Type

Conference Paper

Publication Date


Publication Details

Andrew McInerney and Miles Brown, Modernising an Underground Gas Drainage System in Response to Increased Production and Gas Content, in Naj Aziz and Bob Kininmonth (eds.), Proceedings of the 16th Coal Operators' Conference, Mining Engineering, University of Wollongong, 10-12 February 2016, 297-309.


This paper highlights a successful step change in the management of increasing gas contents and compressed drainage timeframes. The improvements have overcome safety risks concerned with a system not suitable for handling the required gas loading for current and future production targets. The paper discusses how the upgrades manage increasing seam gas content, high rig drilling rates, record development and longwall performance. Improvements to the system included specific design to suit continuity, in-seam hole stability, predicted peak gas flows, drilling and drainage direction, infrastructure type and capacity, formation of empirical gas decay curves and fines and water removal from the system. Using data captured from the commencement of the upgrade, steps toward an efficient and malleable long and short term design and planning tool have been taken. Variable flow rates has led to the investigation of high fluctuation of gas capture, moving away from traditional prediction methods and relying on analysed mine specific data.