The third and fourth in a series of underground coal gasification experiments conducted by the Laramie Energy Technology Center at a site near Hanna, Wyoming, are currently underway. This paper describes the process conditions and includes some pertinent information for these two experiments. Approximately 2800 tons of coal were gasified on Hanna III during a 38-day gasification period with production rates of up to 10 MM scf/day of 138 Btu/scf product gas. Groundwater sampling and analyses to determine the potential impacts of underground coal gasification on groundwater quality are ongoing.The Hanna IV experiment is significantly larger than previous experiments. It consists of a 3-well pattern, in line, with 100-foot and 150-foot spacings. Insifficient site characterization and severe technical inability to correct an override situation across the 100-foot well spacing resulted in a premature shutdown. Preparations are being made to continue the experiment and recover from the override situation.